refs #7983 let plugins add or remove fields to websites and better settings api

56 files changed, 2336 insertions, 1492 deletions

diff --git a/core/API/DataTableManipulator/ReportTotalsCalculator.php b/core/API/DataTableManipulator/ReportTotalsCalculator.php
index 7906077b1e..e1e467d0c1 100644
--- a/core/API/DataTableManipulator/ReportTotalsCalculator.php
+++ b/core/API/DataTableManipulator/ReportTotalsCalculator.php
@@ -13,7 +13,7 @@ use Piwik\DataTable;
 use Piwik\Metrics;
 use Piwik\Period;
 use Piwik\Plugin\Report;
-use Piwik\Plugin\Reports;
+use Piwik\Plugin\ReportsProvider;
 
 /**
  * This class is responsible for setting the metadata property 'totals' on each dataTable if the report
@@ -212,7 +212,7 @@ class ReportTotalsCalculator extends DataTableManipulator
 
     private function findFirstLevelReport()
     {
-        $reports = new Reports();
+        $reports = new ReportsProvider();
         foreach ($reports->getAllReports() as $report) {
             $actionToLoadSubtables = $report->getActionToLoadSubTables();
             if ($actionToLoadSubtables == $this->apiMethod
diff --git a/core/API/DataTablePostProcessor.php b/core/API/DataTablePostProcessor.php
index c6424ea793..c2fdd1569c 100644
--- a/core/API/DataTablePostProcessor.php
+++ b/core/API/DataTablePostProcessor.php
@@ -19,7 +19,7 @@ use Piwik\DataTable\Filter\PivotByDimension;
 use Piwik\Metrics\Formatter;
 use Piwik\Plugin\ProcessedMetric;
 use Piwik\Plugin\Report;
-use Piwik\Plugin\Reports;
+use Piwik\Plugin\ReportsProvider;
 
 /**
  * Processes DataTables that should be served through Piwik's APIs. This processing handles
@@ -72,7 +72,7 @@ class DataTablePostProcessor
         $this->apiMethod = $apiMethod;
         $this->setRequest($request);
 
-        $this->report = Reports::factory($apiModule, $apiMethod);
+        $this->report = ReportsProvider::factory($apiModule, $apiMethod);
         $this->apiInconsistencies = new Inconsistencies();
         $this->setFormatter(new Formatter());
     }
diff --git a/core/DataTable/Filter/PivotByDimension.php b/core/DataTable/Filter/PivotByDimension.php
index bbc72f46d9..f668afb0b9 100644
--- a/core/DataTable/Filter/PivotByDimension.php
+++ b/core/DataTable/Filter/PivotByDimension.php
@@ -21,7 +21,7 @@ use Piwik\Period;
 use Piwik\Piwik;
 use Piwik\Plugin\Report;
 use Piwik\Plugin\Segment;
-use Piwik\Plugin\Reports;
+use Piwik\Plugin\ReportsProvider;
 use Piwik\Site;
 
 /**
@@ -329,7 +329,7 @@ class PivotByDimension extends BaseFilter
     {
         list($module, $method) = explode('.', $report);
 
-        $this->thisReport = Reports::factory($module, $method);
+        $this->thisReport = ReportsProvider::factory($module, $method);
         if (empty($this->thisReport)) {
             throw new Exception("Unable to find report '$report'.");
         }
diff --git a/core/DataTable/Renderer/Xml.php b/core/DataTable/Renderer/Xml.php
index b01f5596a2..31e56a4fde 100644
--- a/core/DataTable/Renderer/Xml.php
+++ b/core/DataTable/Renderer/Xml.php
@@ -176,9 +176,9 @@ class Xml extends Renderer
             }
 
             // render the array item
-            if (is_array($value)) {
+            if (is_array($value) || $value instanceof \stdClass) {
                 $result .= $prefixLines . $prefix . "\n";
-                $result .= $this->renderArray($value, $prefixLines . "\t");
+                $result .= $this->renderArray((array) $value, $prefixLines . "\t");
                 $result .= $prefixLines . $suffix . "\n";
             } elseif ($value instanceof DataTable
                 || $value instanceof Map
@@ -198,6 +198,7 @@ class Xml extends Renderer
                 }
             } else {
                 $xmlValue = self::formatValueXml($value);
+
                 if (strlen($xmlValue) != 0) {
                     $result .= $prefixLines . $prefix . $xmlValue . $suffix . "\n";
                 } else {
diff --git a/core/Db/Schema/Mysql.php b/core/Db/Schema/Mysql.php
index 07cb1490d0..61532c47ef 100644
--- a/core/Db/Schema/Mysql.php
+++ b/core/Db/Schema/Mysql.php
@@ -76,11 +76,21 @@ class Mysql implements SchemaInterface
                             ) ENGINE=$engine DEFAULT CHARSET=utf8
             ",
 
+            'plugin_setting' => "CREATE TABLE {$prefixTables}plugin_setting (
+                          `plugin_name` VARCHAR(60) NOT NULL,
+                          `setting_name` VARCHAR(255) NOT NULL,
+                          `setting_value` LONGTEXT NOT NULL,
+                          `user_login` VARCHAR(100) NOT NULL DEFAULT '',
+                              INDEX(plugin_name, user_login)
+                            ) ENGINE=$engine DEFAULT CHARSET=utf8
+            ",
+
             'site_setting'    => "CREATE TABLE {$prefixTables}site_setting (
                           idsite INTEGER(10) UNSIGNED NOT NULL AUTO_INCREMENT,
+                          `plugin_name` VARCHAR(60) NOT NULL,
                           `setting_name` VARCHAR(255) NOT NULL,
                           `setting_value` LONGTEXT NOT NULL,
-                              PRIMARY KEY(idsite, setting_name)
+                              INDEX(idsite, plugin_name)
                             ) ENGINE=$engine DEFAULT CHARSET=utf8
             ",
 
diff --git a/core/Http/ControllerResolver.php b/core/Http/ControllerResolver.php
index e0fe7d98e3..b9e71b0f11 100644
--- a/core/Http/ControllerResolver.php
+++ b/core/Http/ControllerResolver.php
@@ -12,9 +12,9 @@ use DI\FactoryInterface;
 use Exception;
 use Piwik\Plugin;
 use Piwik\Plugin\Controller;
-use Piwik\Plugin\Reports;
+use Piwik\Plugin\ReportsProvider;
 use Piwik\Session;
-use Piwik\Plugin\Widgets;
+use Piwik\Plugin\WidgetsProvider;
 
 /**
  * Resolves the controller that will handle the request.
@@ -29,11 +29,11 @@ class ControllerResolver
     private $abstractFactory;
 
     /**
-     * @var Widgets
+     * @var WidgetsProvider
      */
     private $widgets;
 
-    public function __construct(FactoryInterface $abstractFactory, Widgets $widgets)
+    public function __construct(FactoryInterface $abstractFactory, WidgetsProvider $widgets)
     {
         $this->abstractFactory = $abstractFactory;
         $this->widgets = $widgets;
@@ -100,7 +100,7 @@ class ControllerResolver
 
     private function createReportController($module, $action, array &$parameters)
     {
-        $report = Reports::factory($module, $action);
+        $report = ReportsProvider::factory($module, $action);
 
         if (!$report) {
             return null;
diff --git a/core/Measurable/Measurable.php b/core/Measurable/Measurable.php
index d80c1f0323..6223a6931f 100644
--- a/core/Measurable/Measurable.php
+++ b/core/Measurable/Measurable.php
@@ -9,7 +9,6 @@
 
 namespace Piwik\Measurable;
 
-use Exception;
 use Piwik\Site;
 
 /**
@@ -17,16 +16,4 @@ use Piwik\Site;
  */
 class Measurable extends Site
 {
-
-    public function getSettingValue($name)
-    {
-        $settings = new MeasurableSettings($this->id, $this->getType());
-        $setting  = $settings->getSetting($name);
-
-        if (!empty($setting)) {
-            return $setting->getValue(); // Calling `getValue` makes sure we respect read permission of this setting
-        }
-
-        throw new Exception(sprintf('Setting %s does not exist', $name));
-    }
 }
diff --git a/core/Measurable/MeasurableSetting.php b/core/Measurable/MeasurableSetting.php
deleted file mode 100644
index 91e0970442..0000000000
--- a/core/Measurable/MeasurableSetting.php
+++ /dev/null
@@ -1,70 +0,0 @@
-<?php
-/**
- * Piwik - free/libre analytics platform
- *
- * @link http://piwik.org
- * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
- *
- */
-
-namespace Piwik\Measurable;
-
-use Piwik\Piwik;
-
-/**
- * Describes a Type setting for a website, mobile app, ...
- *
- * See {@link \Piwik\Plugin\Settings}.
- */
-class MeasurableSetting extends \Piwik\Settings\Setting
-{
-    /**
-     * By default the value of the type setting is only readable by users having at least view access to one site
-     *
-     * @var bool
-     * @since 2.14.0
-     */
-    public $readableByCurrentUser = false;
-
-    /**
-     * By default the value of the type setting is only writable by users having at least admin access to one site
-     * @var bool
-     * @internal
-     */
-    public $writableByCurrentUser = false;
-
-    /**
-     * Constructor.
-     *
-     * @param string $name The persisted name of the setting.
-     * @param string $title The display name of the setting.
-     */
-    public function __construct($name, $title)
-    {
-        parent::__construct($name, $title);
-
-        $this->writableByCurrentUser = Piwik::isUserHasSomeAdminAccess();
-        $this->readableByCurrentUser = Piwik::isUserHasSomeViewAccess();
-    }
-
-    /**
-     * Returns `true` if this setting is writable for the current user, `false` if otherwise. In case it returns
-     * writable for the current user it will be visible in the Plugin settings UI.
-     *
-     * @return bool
-     */
-    public function isWritableByCurrentUser()
-    {
-        return $this->writableByCurrentUser;
-    }
-
-    /**
-     * Returns `true` if this setting can be displayed for the current user, `false` if otherwise.
-     *
-     * @return bool
-     */
-    public function isReadableByCurrentUser()
-    {
-        return $this->readableByCurrentUser;
-    }
-}
diff --git a/core/Measurable/MeasurableSettings.php b/core/Measurable/MeasurableSettings.php
deleted file mode 100644
index 7d627e0a2c..0000000000
--- a/core/Measurable/MeasurableSettings.php
+++ /dev/null
@@ -1,103 +0,0 @@
-<?php
-/**
- * Piwik - free/libre analytics platform
- *
- * @link http://piwik.org
- * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
- *
- */
-namespace Piwik\Measurable;
-
-use Piwik\Db;
-use Piwik\Piwik;
-use Piwik\Plugin\Settings;
-use Piwik\Measurable\Settings\Storage;
-use Piwik\Settings\Setting;
-use Piwik\Measurable\Type\TypeManager;
-
-class MeasurableSettings extends Settings
-{
-
-    /**
-     * @var int
-     */
-    private $idSite = null;
-
-    /**
-     * @var string
-     */
-    private $idType = null;
-
-    /**
-     * @param int $idSite The id of a site. If you want to get settings for a not yet created site just pass an empty value ("0")
-     * @param string $idType If no typeId is given, the type of the site will be used.
-     *
-     * @throws \Exception
-     */
-    public function __construct($idSite, $idType)
-    {
-        $this->idSite = $idSite;
-        $this->idType = $idType;
-        $this->storage = new Storage(Db::get(), $this->idSite);
-        $this->pluginName = 'MeasurableSettings';
-
-        $this->init();
-    }
-
-    protected function init()
-    {
-        $typeManager = new TypeManager();
-        $type = $typeManager->getType($this->idType);
-        $type->configureMeasurableSettings($this);
-
-        /**
-         * This event is posted when generating settings for a Measurable (website). You can add any Measurable settings
-         * that you wish to be shown in the Measurable manager (websites manager). If you need to add settings only for
-         * eg MobileApp measurables you can use eg `$type->getId() === Piwik\Plugins\MobileAppMeasurable\Type::ID` and
-         * add only settings if the condition is true.
-         *
-         * @since Piwik 2.14.0
-         * @deprecated will be removed in Piwik 3.0.0
-         *
-         * @param MeasurableSettings $this
-         * @param \Piwik\Measurable\Type $type
-         * @param int $idSite
-         */
-        Piwik::postEvent('Measurable.initMeasurableSettings', array($this, $type, $this->idSite));
-    }
-
-    public function addSetting(Setting $setting)
-    {
-        if ($this->idSite && $setting instanceof MeasurableSetting) {
-            $setting->writableByCurrentUser = Piwik::isUserHasAdminAccess($this->idSite);
-        }
-
-        parent::addSetting($setting);
-    }
-
-    public function save()
-    {
-        Piwik::checkUserHasAdminAccess($this->idSite);
-
-        $typeManager = new TypeManager();
-        $type = $typeManager->getType($this->idType);
-
-        /**
-         * Triggered just before Measurable settings are about to be saved. You can use this event for example
-         * to validate not only one setting but multiple ssetting. For example whether username
-         * and password matches.
-         *
-         * @since Piwik 2.14.0
-         * @deprecated will be removed in Piwik 3.0.0
-         *
-         * @param MeasurableSettings $this
-         * @param \Piwik\Measurable\Type $type
-         * @param int $idSite
-         */
-        Piwik::postEvent('Measurable.beforeSaveSettings', array($this, $type, $this->idSite));
-
-        $this->storage->save();
-    }
-
-}
-
diff --git a/core/Measurable/Settings/Storage.php b/core/Measurable/Settings/Storage.php
deleted file mode 100644
index df9748af5e..0000000000
--- a/core/Measurable/Settings/Storage.php
+++ /dev/null
@@ -1,104 +0,0 @@
-<?php
-/**
- * Piwik - free/libre analytics platform
- *
- * @link http://piwik.org
- * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
- *
- */
-
-namespace Piwik\Measurable\Settings;
-
-use Piwik\Db;
-use Piwik\Common;
-use Piwik\Settings\Setting;
-
-/**
- * Storage for site settings
- */
-class Storage extends \Piwik\Settings\Storage
-{
-    private $idSite = null;
-
-    /**
-     * @var Db
-     */
-    private $db = null;
-
-    private $toBeDeleted = array();
-
-    public function __construct(Db\AdapterInterface $db, $idSite)
-    {
-        $this->db     = $db;
-        $this->idSite = $idSite;
-    }
-
-    protected function deleteSettingsFromStorage()
-    {
-        $table = $this->getTableName();
-        $sql   = "DELETE FROM $table WHERE `idsite` = ?";
-        $bind  = array($this->idSite);
-
-        $this->db->query($sql, $bind);
-    }
-
-    public function deleteValue(Setting $setting)
-    {
-        $this->toBeDeleted[$setting->getName()] = true;
-        parent::deleteValue($setting);
-    }
-
-    public function setValue(Setting $setting, $value)
-    {
-        $this->toBeDeleted[$setting->getName()] = false; // prevent from deleting this setting, we will create/update it
-        parent::setValue($setting, $value);
-    }
-
-    /**
-     * Saves (persists) the current setting values in the database.
-     */
-    public function save()
-    {
-        $table = $this->getTableName();
-
-        foreach ($this->toBeDeleted as $name => $delete) {
-            if ($delete) {
-                $sql  = "DELETE FROM $table WHERE `idsite` = ? and `setting_name` = ?";
-                $bind = array($this->idSite, $name);
-
-                $this->db->query($sql, $bind);
-            }
-        }
-
-        $this->toBeDeleted = array();
-
-        foreach ($this->settingsValues as $name => $value) {
-            $value = serialize($value);
-
-            $sql  = "INSERT INTO $table (`idsite`, `setting_name`, `setting_value`) VALUES (?, ?, ?) ON DUPLICATE KEY UPDATE `setting_value` = ?";
-            $bind = array($this->idSite, $name, $value, $value);
-
-            $this->db->query($sql, $bind);
-        }
-    }
-
-    protected function loadSettings()
-    {
-        $sql  = "SELECT `setting_name`, `setting_value` FROM " . $this->getTableName() . " WHERE idsite = ?";
-        $bind = array($this->idSite);
-
-        $settings =$this->db->fetchAll($sql, $bind);
-
-        $flat = array();
-        foreach ($settings as $setting) {
-            $flat[$setting['setting_name']] = unserialize($setting['setting_value']);
-        }
-
-        return $flat;
-    }
-
-    private function getTableName()
-    {
-        return Common::prefixTable('site_setting');
-    }
-}
diff --git a/core/Measurable/Type.php b/core/Measurable/Type.php
index e9457a660f..5d24f04409 100644
--- a/core/Measurable/Type.php
+++ b/core/Measurable/Type.php
@@ -55,8 +55,5 @@ class Type
         return $this->howToSetupUrl;
     }
 
-    public function configureMeasurableSettings(MeasurableSettings $settings)
-    {
-    }
 }
 
diff --git a/core/Measurable/Type/TypeManager.php b/core/Measurable/Type/TypeManager.php
index af40d9c624..a514abbbdc 100644
--- a/core/Measurable/Type/TypeManager.php
+++ b/core/Measurable/Type/TypeManager.php
@@ -8,6 +8,7 @@
  */
 namespace Piwik\Measurable\Type;
 
+use Piwik\Container\StaticContainer;
 use Piwik\Plugin\Manager as PluginManager;
 use Piwik\Measurable\Type;
 
@@ -18,7 +19,14 @@ class TypeManager
      */
     public function getAllTypes()
     {
-        return PluginManager::getInstance()->findComponents('Type', '\\Piwik\\Measurable\\Type');
+        $components = PluginManager::getInstance()->findComponents('Type', '\\Piwik\\Measurable\\Type');
+
+        $instances = array();
+        foreach ($components as $component) {
+            $instances[] = StaticContainer::get($component);
+        }
+
+        return $instances;
     }
 
     /**
diff --git a/core/Menu/MenuAbstract.php b/core/Menu/MenuAbstract.php
index 777d97b523..25e6ce0f53 100644
--- a/core/Menu/MenuAbstract.php
+++ b/core/Menu/MenuAbstract.php
@@ -8,6 +8,7 @@
  */
 namespace Piwik\Menu;
 
+use Piwik\Container\StaticContainer;
 use Piwik\Plugins\SitesManager\API;
 use Piwik\Singleton;
 use Piwik\Plugin\Manager as PluginManager;
@@ -71,7 +72,12 @@ abstract class MenuAbstract extends Singleton
             return self::$menus;
         }
 
-        self::$menus = PluginManager::getInstance()->findComponents('Menu', 'Piwik\\Plugin\\Menu');
+        $components = PluginManager::getInstance()->findComponents('Menu', 'Piwik\\Plugin\\Menu');
+
+        self::$menus = array();
+        foreach ($components as $component) {
+            self::$menus[] = StaticContainer::get($component);
+        }
 
         return self::$menus;
     }
diff --git a/core/Notification/Manager.php b/core/Notification/Manager.php
index bdf1f130dd..4ae3acde42 100644
--- a/core/Notification/Manager.php
+++ b/core/Notification/Manager.php
@@ -129,6 +129,10 @@ class Manager
 
     private static function removeOldestNotificationsIfThereAreTooMany()
     {
+        if (!self::isSessionEnabled()) {
+            return;
+        }
+
         $maxNotificationsInSession = 30;
 
         $session = static::getSession();
diff --git a/core/Plugin.php b/core/Plugin.php
index 852e09522e..91d5a8a8ad 100644
--- a/core/Plugin.php
+++ b/core/Plugin.php
@@ -324,7 +324,7 @@ class Plugin
      *                                   given subclass. If the requested file exists but does not extend this class
      *                                   a warning will be shown to advice a developer to extend this certain class.
      *
-     * @return \stdClass|null  Null if the requested component does not exist or an instance of the found
+     * @return string|null  Null if the requested component does not exist or an instance of the found
      *                         component.
      */
     public function findComponent($componentName, $expectedSubclass)
@@ -369,7 +369,7 @@ class Plugin
             $this->cache->save($cacheId, $classname);
         }
 
-        return StaticContainer::get($classname);
+        return $classname;
     }
 
     public function findMultipleComponents($directoryWithinPlugin, $expectedSubclass)
diff --git a/core/Plugin/API.php b/core/Plugin/API.php
index c54e10a82b..0f48816af3 100644
--- a/core/Plugin/API.php
+++ b/core/Plugin/API.php
@@ -86,6 +86,16 @@ abstract class API
     }
 
     /**
+     * Used in tests only
+     * @ignore
+     * @deprecated
+     */
+    public static function unsetAllInstances()
+    {
+        self::$instances = array();
+    }
+
+    /**
      * Sets the singleton instance. For testing purposes.
      * @ignore
      * @deprecated
diff --git a/core/Plugin/Controller.php b/core/Plugin/Controller.php
index 74691e577c..ad4addf85c 100644
--- a/core/Plugin/Controller.php
+++ b/core/Plugin/Controller.php
@@ -33,7 +33,7 @@ use Piwik\Piwik;
 use Piwik\Plugins\CoreAdminHome\CustomLogo;
 use Piwik\Plugins\CoreVisualizations\Visualizations\JqplotGraph\Evolution;
 use Piwik\Plugins\LanguagesManager\LanguagesManager;
-use Piwik\Plugin\Reports;
+use Piwik\Plugin\ReportsProvider;
 use Piwik\SettingsPiwik;
 use Piwik\Site;
 use Piwik\Url;
@@ -314,7 +314,7 @@ abstract class Controller
     protected function renderReport($apiAction, $controllerAction = false)
     {
         if (empty($controllerAction) && is_string($apiAction)) {
-            $report = Reports::factory($this->pluginName, $apiAction);
+            $report = ReportsProvider::factory($this->pluginName, $apiAction);
 
             if (!empty($report)) {
                 $apiAction = $report;
diff --git a/core/Plugin/Manager.php b/core/Plugin/Manager.php
index 2b552f48e0..b490451747 100644
--- a/core/Plugin/Manager.php
+++ b/core/Plugin/Manager.php
@@ -12,8 +12,11 @@ namespace Piwik\Plugin;
 use Piwik\Application\Kernel\PluginList;
 use Piwik\Cache;
 use Piwik\Columns\Dimension;
+use Piwik\Common;
 use Piwik\Config as PiwikConfig;
 use Piwik\Config;
+use Piwik\Db;
+use Piwik\Settings\Storage as SettingsStorage;
 use Piwik\Container\StaticContainer;
 use Piwik\EventDispatcher;
 use Piwik\Filesystem;
@@ -398,7 +401,8 @@ class Manager
         }
         $this->loadAllPluginsAndGetTheirInfo();
 
-        \Piwik\Settings\Manager::cleanupPluginSettings($pluginName);
+        SettingsStorage\Backend\PluginSettingsTable::removeAllSettingsForPlugin($pluginName);
+        SettingsStorage\Backend\MeasurableSettingsTable::removeAllSettingsForPlugin($pluginName);
 
         $this->executePluginDeactivate($pluginName);
         $this->executePluginUninstall($pluginName);
diff --git a/core/Plugin/Menu.php b/core/Plugin/Menu.php
index 384c3a199a..99275a5aeb 100644
--- a/core/Plugin/Menu.php
+++ b/core/Plugin/Menu.php
@@ -236,7 +236,7 @@ class Menu
         }
 
         $reportAction = lcfirst(substr($action, 4));
-        if (Reports::factory($module, $reportAction)) {
+        if (ReportsProvider::factory($module, $reportAction)) {
             return;
         }
 
diff --git a/core/Plugin/Report.php b/core/Plugin/Report.php
index c98d38e849..38e4857498 100644
--- a/core/Plugin/Report.php
+++ b/core/Plugin/Report.php
@@ -20,7 +20,7 @@ use Piwik\Cache as PiwikCache;
 use Piwik\Piwik;
 use Piwik\Plugins\CoreVisualizations\Visualizations\HtmlTable;
 use Piwik\Plugins\CoreVisualizations\Visualizations\JqplotGraph\Evolution;
-use Piwik\Plugin\Reports;
+use Piwik\Plugin\ReportsProvider;
 use Piwik\ViewDataTable\Factory as ViewDataTableFactory;
 use Exception;
 use Piwik\Widget\WidgetsList;
@@ -699,7 +699,7 @@ class Report
 
         list($subtableReportModule, $subtableReportAction) = $this->getSubtableApiMethod();
 
-        $subtableReport = Reports::factory($subtableReportModule, $subtableReportAction);
+        $subtableReport = ReportsProvider::factory($subtableReportModule, $subtableReportAction);
         if (empty($subtableReport)) {
             return null;
         }
diff --git a/core/Plugin/Reports.php b/core/Plugin/ReportsProvider.php
index 56d69e5453..021ca891fe 100644
--- a/core/Plugin/Reports.php
+++ b/core/Plugin/ReportsProvider.php
@@ -16,7 +16,7 @@ use Piwik\Cache as PiwikCache;
 /**
  * Get reports that are defined by plugins.
  */
-class Reports
+class ReportsProvider
 {
 
     /**
diff --git a/core/Plugin/Settings.php b/core/Plugin/Settings.php
deleted file mode 100644
index c26581e4b1..0000000000
--- a/core/Plugin/Settings.php
+++ /dev/null
@@ -1,308 +0,0 @@
-<?php
-/**
- * Piwik - free/libre analytics platform
- *
- * @link http://piwik.org
- * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
- *
- */
-namespace Piwik\Plugin;
-
-use Piwik\Piwik;
-use Piwik\Settings\Setting;
-use Piwik\Settings\Storage;
-use Piwik\Settings\StorageInterface;
-use Piwik\Tracker\SettingsStorage;
-
-/**
- * Base class of all plugin settings providers. Plugins that define their own configuration settings
- * can extend this class to easily make their settings available to Piwik users.
- *
- * Descendants of this class should implement the {@link init()} method and call the
- * {@link addSetting()} method for each of the plugin's settings.
- *
- * For an example, see the {@link Piwik\Plugins\ExampleSettingsPlugin\ExampleSettingsPlugin} plugin.
- *
- * @api
- */
-abstract class Settings
-{
-    const TYPE_INT    = 'integer';
-    const TYPE_FLOAT  = 'float';
-    const TYPE_STRING = 'string';
-    const TYPE_BOOL   = 'boolean';
-    const TYPE_ARRAY  = 'array';
-
-    const CONTROL_RADIO    = 'radio';
-    const CONTROL_TEXT     = 'text';
-    const CONTROL_TEXTAREA = 'textarea';
-    const CONTROL_CHECKBOX = 'checkbox';
-    const CONTROL_PASSWORD = 'password';
-    const CONTROL_MULTI_SELECT  = 'multiselect';
-    const CONTROL_SINGLE_SELECT = 'select';
-
-    /**
-     * An array containing all available settings: Array ( [setting-name] => [setting] )
-     *
-     * @var Settings[]
-     */
-    private $settings = array();
-
-    private $introduction;
-    protected $pluginName;
-
-    /**
-     * @var StorageInterface
-     */
-    protected $storage;
-
-    /**
-     * Constructor.
-     */
-    public function __construct($pluginName = null)
-    {
-        if (!empty($pluginName)) {
-            $this->pluginName = $pluginName;
-        } else {
-            $classname = get_class($this);
-            $parts     = explode('\\', $classname);
-
-            if (3 <= count($parts)) {
-                $this->pluginName = $parts[2];
-            }
-        }
-
-        $this->storage = Storage\Factory::make($this->pluginName);
-
-        $this->init();
-    }
-
-    /**
-     * @ignore
-     */
-    public function getPluginName()
-    {
-        return $this->pluginName;
-    }
-
-    /**
-     * @ignore
-     * @return Setting
-     */
-    public function getSetting($name)
-    {
-        if (array_key_exists($name, $this->settings)) {
-            return $this->settings[$name];
-        }
-    }
-
-    /**
-     * Implemented by descendants. This method should define plugin settings (via the
-     * {@link addSetting()}) method and set the introduction text (via the
-     * {@link setIntroduction()}).
-     */
-    abstract protected function init();
-
-    /**
-     * Sets the text used to introduce this plugin's settings in the _Plugin Settings_ page.
-     *
-     * @param string $introduction
-     */
-    protected function setIntroduction($introduction)
-    {
-        $this->introduction = $introduction;
-    }
-
-    /**
-     * Returns the introduction text for this plugin's settings.
-     *
-     * @return string
-     */
-    public function getIntroduction()
-    {
-        return $this->introduction;
-    }
-
-    /**
-     * Returns the settings that can be displayed for the current user.
-     *
-     * @return Setting[]
-     */
-    public function getSettingsForCurrentUser()
-    {
-        $settings = array_filter($this->getSettings(), function (Setting $setting) {
-            return $setting->isWritableByCurrentUser();
-        });
-
-        $settings2 = $settings;
-
-        uasort($settings, function ($setting1, $setting2) use ($settings2) {
-
-            /** @var Setting $setting1 */ /** @var Setting $setting2 */
-            if ($setting1->getOrder() == $setting2->getOrder()) {
-                // preserve order for settings having same order
-                foreach ($settings2 as $setting) {
-                    if ($setting1 === $setting) {
-                        return -1;
-                    }
-                    if ($setting2 === $setting) {
-                        return 1;
-                    }
-                }
-
-                return 0;
-            }
-
-            return $setting1->getOrder() > $setting2->getOrder() ? -1 : 1;
-        });
-
-        return $settings;
-    }
-
-    /**
-     * Returns all available settings. This will include settings that are not available
-     * to the current user (such as settings available only to the Super User).
-     *
-     * @return Setting[]
-     */
-    public function getSettings()
-    {
-        return $this->settings;
-    }
-
-    /**
-     * Makes a new plugin setting available.
-     *
-     * @param Setting $setting
-     * @throws \Exception       If there is a setting with the same name that already exists.
-     *                          If the name contains non-alphanumeric characters.
-     */
-    protected function addSetting(Setting $setting)
-    {
-        $name = $setting->getName();
-
-        if (!ctype_alnum(str_replace('_', '', $name))) {
-            $msg = sprintf('The setting name "%s" in plugin "%s" is not valid. Only underscores, alpha and numerical characters are allowed', $setting->getName(), $this->pluginName);
-            throw new \Exception($msg);
-        }
-
-        if (array_key_exists($name, $this->settings)) {
-            throw new \Exception(sprintf('A setting with name "%s" does already exist for plugin "%s"', $setting->getName(), $this->pluginName));
-        }
-
-        $this->setDefaultTypeAndFieldIfNeeded($setting);
-        $this->addValidatorIfNeeded($setting);
-
-        $setting->setStorage($this->storage);
-        $setting->setPluginName($this->pluginName);
-
-        $this->settings[$name] = $setting;
-    }
-
-    /**
-     * Saves (persists) the current setting values in the database.
-     */
-    public function save()
-    {
-        $this->storage->save();
-
-        SettingsStorage::clearCache();
-
-        /**
-         * Triggered after a plugin settings have been updated.
-         *
-         * **Example**
-         *
-         *     Piwik::addAction('Settings.MyPlugin.settingsUpdated', function (Settings $settings) {
-         *         $value = $settings->someSetting->getValue();
-         *         // Do something with the new setting value
-         *     });
-         *
-         * @param Settings $settings The plugin settings object.
-         */
-        Piwik::postEvent(sprintf('Settings.%s.settingsUpdated', $this->pluginName), array($this));
-    }
-
-    /**
-     * Removes all settings for this plugin from the database. Useful when uninstalling
-     * a plugin.
-     */
-    public function removeAllPluginSettings()
-    {
-        Piwik::checkUserHasSuperUserAccess();
-
-        $this->storage->deleteAllValues();
-
-        SettingsStorage::clearCache();
-    }
-
-    private function getDefaultType($controlType)
-    {
-        $defaultTypes = array(
-            static::CONTROL_TEXT          => static::TYPE_STRING,
-            static::CONTROL_TEXTAREA      => static::TYPE_STRING,
-            static::CONTROL_PASSWORD      => static::TYPE_STRING,
-            static::CONTROL_CHECKBOX      => static::TYPE_BOOL,
-            static::CONTROL_MULTI_SELECT  => static::TYPE_ARRAY,
-            static::CONTROL_RADIO         => static::TYPE_STRING,
-            static::CONTROL_SINGLE_SELECT => static::TYPE_STRING,
-        );
-
-        return $defaultTypes[$controlType];
-    }
-
-    private function getDefaultCONTROL($type)
-    {
-        $defaultControlTypes = array(
-            static::TYPE_INT    => static::CONTROL_TEXT,
-            static::TYPE_FLOAT  => static::CONTROL_TEXT,
-            static::TYPE_STRING => static::CONTROL_TEXT,
-            static::TYPE_BOOL   => static::CONTROL_CHECKBOX,
-            static::TYPE_ARRAY  => static::CONTROL_MULTI_SELECT,
-        );
-
-        return $defaultControlTypes[$type];
-    }
-
-    private function setDefaultTypeAndFieldIfNeeded(Setting $setting)
-    {
-        $hasControl = !is_null($setting->uiControlType);
-        $hasType    = !is_null($setting->type);
-
-        if ($hasControl && !$hasType) {
-            $setting->type = $this->getDefaultType($setting->uiControlType);
-        } elseif ($hasType && !$hasControl) {
-            $setting->uiControlType = $this->getDefaultCONTROL($setting->type);
-        } elseif (!$hasControl && !$hasType) {
-            $setting->type = static::TYPE_STRING;
-            $setting->uiControlType = static::CONTROL_TEXT;
-        }
-    }
-
-    private function addValidatorIfNeeded(Setting $setting)
-    {
-        if (!is_null($setting->validate) || is_null($setting->availableValues)) {
-            return;
-        }
-
-        $pluginName = $this->pluginName;
-
-        $setting->validate = function ($value) use ($setting, $pluginName) {
-
-            $errorMsg = Piwik::translate('CoreAdminHome_PluginSettingsValueNotAllowed',
-                array($setting->title, $pluginName));
-
-            if (is_array($value) && $setting->type == Settings::TYPE_ARRAY) {
-                foreach ($value as $val) {
-                    if (!array_key_exists($val, $setting->availableValues)) {
-                        throw new \Exception($errorMsg);
-                    }
-                }
-            } else {
-                if (!array_key_exists($value, $setting->availableValues)) {
-                    throw new \Exception($errorMsg);
-                }
-            }
-        };
-    }
-}
diff --git a/core/Plugin/SettingsProvider.php b/core/Plugin/SettingsProvider.php
new file mode 100644
index 0000000000..5cc05bd32c
--- /dev/null
+++ b/core/Plugin/SettingsProvider.php
@@ -0,0 +1,215 @@
+<?php
+/**
+ * Piwik - free/libre analytics platform
+ *
+ * @link http://piwik.org
+ * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
+ *
+ */
+namespace Piwik\Plugin;
+
+use Piwik\CacheId;
+use Piwik\Container\StaticContainer;
+use Piwik\Plugin;
+use Piwik\Cache as PiwikCache;
+use Piwik\Settings\Measurable\MeasurableSettings;
+use \Piwik\Settings\Plugin\UserSettings;
+use \Piwik\Settings\Plugin\SystemSettings;
+
+/**
+ * Base class of all plugin settings providers. Plugins that define their own configuration settings
+ * can extend this class to easily make their settings available to Piwik users.
+ *
+ * Descendants of this class should implement the {@link init()} method and call the
+ * {@link addSetting()} method for each of the plugin's settings.
+ *
+ * For an example, see the {@link Piwik\Plugins\ExampleSettingsPlugin\ExampleSettingsPlugin} plugin.
+ */
+class SettingsProvider
+{
+    /**
+     * @var Plugin\Manager
+     */
+    private $pluginManager;
+
+    public function __construct(Plugin\Manager $pluginManager)
+    {
+        $this->pluginManager = $pluginManager;
+    }
+
+    /**
+     *
+     * Get user settings implemented by a specific plugin (if implemented by this plugin).
+     * @param string $pluginName
+     * @return SystemSettings|null
+     */
+    public function getSystemSettings($pluginName)
+    {
+        $plugin = $this->getLoadedAndActivated($pluginName);
+
+        if ($plugin) {
+            $settings = $plugin->findComponent('SystemSettings', 'Piwik\\Settings\\Plugin\\SystemSettings');
+
+            if ($settings) {
+                return StaticContainer::get($settings);
+            }
+        }
+    }
+
+    /**
+     * Get user settings implemented by a specific plugin (if implemented by this plugin).
+     * @param string $pluginName
+     * @return UserSettings|null
+     */
+    public function getUserSettings($pluginName)
+    {
+        $plugin = $this->getLoadedAndActivated($pluginName);
+
+        if ($plugin) {
+            $settings = $plugin->findComponent('UserSettings', 'Piwik\\Settings\\Plugin\\UserSettings');
+
+            if ($settings) {
+                return StaticContainer::get($settings);
+            }
+        }
+    }
+
+    /**
+     * Returns all available system settings. A plugin has to specify a file named `SystemSettings.php` containing a
+     * class named `SystemSettings` that extends `Piwik\Settings\Plugin\SystemSettings` in order to be considered as
+     * a system setting. Otherwise the settings for a plugin won't be available.
+     *
+     * @return SystemSettings[]   An array containing array([pluginName] => [setting instance]).
+     */
+    public function getAllSystemSettings()
+    {
+        $cacheId = CacheId::languageAware('AllSystemSettings');
+        $cache = PiwikCache::getTransientCache();
+
+        if (!$cache->contains($cacheId)) {
+            $pluginNames = $this->pluginManager->getActivatedPlugins();
+            $byPluginName = array();
+
+            foreach ($pluginNames as $plugin) {
+                $component = $this->getSystemSettings($plugin);
+
+                if (!empty($component)) {
+                    $byPluginName[$plugin] = $component;
+                }
+            }
+
+            $cache->save($cacheId, $byPluginName);
+        }
+
+        return $cache->fetch($cacheId);
+    }
+
+    /**
+     * Returns all available user settings. A plugin has to specify a file named `UserSettings.php` containing a class
+     * named `UserSettings` that extends `Piwik\Settings\Plugin\UserSettings` in order to be considered as a plugin
+     * setting. Otherwise the settings for a plugin won't be available.
+     *
+     * @return UserSettings[]   An array containing array([pluginName] => [setting instance]).
+     */
+    public function getAllUserSettings()
+    {
+        $cacheId = CacheId::languageAware('AllUserSettings');
+        $cache = PiwikCache::getTransientCache();
+
+        if (!$cache->contains($cacheId)) {
+            $pluginNames = $this->pluginManager->getActivatedPlugins();
+            $byPluginName = array();
+
+            foreach ($pluginNames as $plugin) {
+                $component = $this->getUserSettings($plugin);
+
+                if (!empty($component)) {
+                    $byPluginName[$plugin] = $component;
+                }
+            }
+
+            $cache->save($cacheId, $byPluginName);
+        }
+
+        return $cache->fetch($cacheId);
+    }
+
+    /**
+     * @api
+     *
+     * Get measurable settings for a specific plugin.
+     *
+     * @param string $pluginName    The name of a plugin.
+     * @param int $idSite           The ID of a site. If a site is about to be created pass idSite = 0.
+     * @param string|null $idType   If null, idType will be detected automatically if the site already exists. Only
+     *                              needed to set a value when idSite = 0 (this is the case when a site is about)
+     *                              to be created.
+     *
+     * @return MeasurableSettings|null  Returns null if no MeasurableSettings implemented by this plugin or when plugin
+     *                                  is not loaded and activated. Returns an instance of the settings otherwise.
+     */
+    public function getMeasurableSettings($pluginName, $idSite, $idType = null)
+    {
+        $plugin = $this->getLoadedAndActivated($pluginName);
+
+        if ($plugin) {
+            $component = $plugin->findComponent('MeasurableSettings', 'Piwik\\Settings\\Measurable\\MeasurableSettings');
+
+            if ($component) {
+                return StaticContainer::getContainer()->make($component, array(
+                    'idSite' => $idSite,
+                    'idMeasurableType' => $idType
+                ));
+            }
+        }
+    }
+
+    /**
+     * @api
+     *
+     * Get all available measurable settings implemented by loaded and activated plugins.
+     *
+     * @param int $idSite           The ID of a site. If a site is about to be created pass idSite = 0.
+     * @param string|null $idMeasurableType   If null, idType will be detected automatically if the site already exists.
+     *                                        Only needed to set a value when idSite = 0 (this is the case when a site
+     *                                        is about) to be created.
+     *
+     * @return MeasurableSettings[]
+     */
+    public function getAllMeasurableSettings($idSite, $idMeasurableType = null)
+    {
+        $pluginNames = $this->pluginManager->getActivatedPlugins();
+        $byPluginName = array();
+
+        foreach ($pluginNames as $plugin) {
+            $component = $this->getMeasurableSettings($plugin, $idSite, $idMeasurableType);
+
+            if (!empty($component)) {
+                $byPluginName[$plugin] = $component;
+            }
+        }
+
+        return $byPluginName;
+    }
+
+    private function getLoadedAndActivated($pluginName)
+    {
+        if (!$this->pluginManager->isPluginLoaded($pluginName)) {
+            return;
+        }
+
+        try {
+            if (!$this->pluginManager->isPluginActivated($pluginName)) {
+                return;
+            }
+
+            $plugin = $this->pluginManager->getLoadedPlugin($pluginName);
+        } catch (\Exception $e) {
+            // we are not allowed to use possible settings from this plugin, plugin is not active
+            return;
+        }
+
+        return $plugin;
+    }
+
+}
diff --git a/core/Plugin/ViewDataTable.php b/core/Plugin/ViewDataTable.php
index 5ca7e2e9ba..3b7bcf4ff8 100644
--- a/core/Plugin/ViewDataTable.php
+++ b/core/Plugin/ViewDataTable.php
@@ -13,7 +13,7 @@ use Piwik\Common;
 use Piwik\DataTable;
 use Piwik\Period;
 use Piwik\Piwik;
-use Piwik\Plugin\Reports;
+use Piwik\Plugin\ReportsProvider;
 use Piwik\View;
 use Piwik\View\ViewInterface;
 use Piwik\ViewDataTable\Config as VizConfig;
@@ -192,7 +192,7 @@ abstract class ViewDataTable implements ViewInterface
 
         $this->requestConfig->apiMethodToRequestDataTable = $apiMethodToRequestDataTable;
 
-        $report = Reports::factory($this->requestConfig->getApiModuleToRequest(), $this->requestConfig->getApiMethodToRequest());
+        $report = ReportsProvider::factory($this->requestConfig->getApiModuleToRequest(), $this->requestConfig->getApiMethodToRequest());
 
         if (!empty($report)) {
             /** @var Report $report */
diff --git a/core/Plugin/Visualization.php b/core/Plugin/Visualization.php
index da2c60c18e..e19da81d9a 100644
--- a/core/Plugin/Visualization.php
+++ b/core/Plugin/Visualization.php
@@ -23,7 +23,7 @@ use Piwik\Period;
 use Piwik\Piwik;
 use Piwik\Plugins\API\API as ApiApi;
 use Piwik\Plugins\PrivacyManager\PrivacyManager;
-use Piwik\Plugin\Reports;
+use Piwik\Plugin\ReportsProvider;
 use Piwik\View;
 use Piwik\ViewDataTable\Manager as ViewDataTableManager;
 use Piwik\Plugin\Manager as PluginManager;
@@ -169,7 +169,7 @@ class Visualization extends ViewDataTable
 
         parent::__construct($controllerAction, $apiMethodToRequestDataTable, $params);
 
-        $this->report = Reports::factory($this->requestConfig->getApiModuleToRequest(), $this->requestConfig->getApiMethodToRequest());
+        $this->report = ReportsProvider::factory($this->requestConfig->getApiModuleToRequest(), $this->requestConfig->getApiMethodToRequest());
     }
 
     public function render()
diff --git a/core/Plugin/Widgets.php b/core/Plugin/WidgetsProvider.php
index e67f2bce61..8fe015411b 100644
--- a/core/Plugin/Widgets.php
+++ b/core/Plugin/WidgetsProvider.php
@@ -19,7 +19,7 @@ use Piwik\Widget\WidgetContainerConfig;
 /**
  * Get widgets that are defined by plugins.
  */
-class Widgets
+class WidgetsProvider
 {
     /**
      * @var Plugin\Manager
diff --git a/core/Scheduler/TaskLoader.php b/core/Scheduler/TaskLoader.php
index 60b9e328b6..95c3394cfb 100644
--- a/core/Scheduler/TaskLoader.php
+++ b/core/Scheduler/TaskLoader.php
@@ -8,6 +8,7 @@
 
 namespace Piwik\Scheduler;
 
+use Piwik\Container\StaticContainer;
 use Piwik\Plugin\Manager as PluginManager;
 use Piwik\Plugin\Tasks;
 
@@ -27,6 +28,7 @@ class TaskLoader
         $pluginTasks = PluginManager::getInstance()->findComponents('Tasks', 'Piwik\Plugin\Tasks');
 
         foreach ($pluginTasks as $pluginTask) {
+            $pluginTask = StaticContainer::get($pluginTask);
             $pluginTask->schedule();
 
             foreach ($pluginTask->getScheduledTasks() as $task) {
diff --git a/core/Settings/FieldConfig.php b/core/Settings/FieldConfig.php
new file mode 100644
index 0000000000..4c75fc1719
--- /dev/null
+++ b/core/Settings/FieldConfig.php
@@ -0,0 +1,208 @@
+<?php
+/**
+ * Piwik - free/libre analytics platform
+ *
+ * @link http://piwik.org
+ * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
+ *
+ */
+
+namespace Piwik\Settings;
+
+/**
+ * Lets you configure a form field.
+ *
+ * @api
+ */
+class FieldConfig
+{
+    /**
+     * Shows a radio field
+     */
+    const UI_CONTROL_RADIO = 'radio';
+
+    /**
+     * Shows a text field
+     */
+    const UI_CONTROL_TEXT = 'text';
+
+    /**
+     * Shows a text area
+     */
+    const UI_CONTROL_TEXTAREA = 'textarea';
+
+    /**
+     * Shows a checkbox
+     */
+    const UI_CONTROL_CHECKBOX = 'checkbox';
+
+    /**
+     * Shows a password field
+     */
+    const UI_CONTROL_PASSWORD = 'password';
+
+    /**
+     * Shows a select field where a user can select multiple values. The type "Array" is required for this ui control.
+     */
+    const UI_CONTROL_MULTI_SELECT = 'multiselect';
+
+    /**
+     * Shows a select field
+     */
+    const UI_CONTROL_SINGLE_SELECT = 'select';
+
+    /**
+     * Generates a hidden form field
+     */
+    const UI_CONTROL_HIDDEN = 'hidden';
+
+    /**
+     * Expects an integer value
+     */
+    const TYPE_INT = 'integer';
+
+    /**
+     * Expects a float value
+     */
+    const TYPE_FLOAT = 'float';
+
+    /**
+     * Expects a string
+     */
+    const TYPE_STRING = 'string';
+
+    /**
+     * Expects a boolean
+     */
+    const TYPE_BOOL = 'boolean';
+
+    /**
+     * Expects an array containing multiple values
+     */
+    const TYPE_ARRAY = 'array';
+
+    /**
+     * Describes what HTML element should be used to manipulate the setting through Piwik's UI.
+     *
+     * See {@link Piwik\Plugin\Settings} for a list of supported control types.
+     *
+     * @var string
+     */
+    public $uiControl = null;
+
+    /**
+     * Name-value mapping of HTML attributes that will be added HTML form control, eg,
+     * `array('size' => 3)`. Attributes will be escaped before outputting.
+     *
+     * @var array
+     */
+    public $uiControlAttributes = array();
+
+    /**
+     * The list of all available values for this setting. If null, the setting can have any value.
+     *
+     * If supplied, this field should be an array mapping available values with their prettified
+     * display value. Eg, if set to `array('nb_visits' => 'Visits', 'nb_actions' => 'Actions')`,
+     * the UI will display **Visits** and **Actions**, and when the user selects one, Piwik will
+     * set the setting to **nb_visits** or **nb_actions** respectively.
+     *
+     * The setting value will be validated if this field is set. If the value is not one of the
+     * available values, an error will be triggered.
+     *
+     * _Note: If a custom validator is supplied (see {@link $validate}), the setting value will
+     * not be validated._
+     *
+     * @var null|array
+     */
+    public $availableValues = null;
+
+    /**
+     * Text that will appear above this setting's section in the _Plugin Settings_ admin page.
+     *
+     * @var null|string
+     */
+    public $introduction = null;
+
+    /**
+     * Text that will appear directly underneath the setting title in the _Plugin Settings_ admin
+     * page. If set, should be a short description of the setting.
+     *
+     * @var null|string
+     */
+    public $description = null;
+
+    /**
+     * Text that will appear next to the setting's section in the _Plugin Settings_ admin page. If set,
+     * it should contain information about the setting that is more specific than a general description,
+     * such as the format of the setting value if it has a special format.
+     *
+     * Be sure to escape any user input as HTML can be used here.
+     *
+     * @var null|string
+     */
+    public $inlineHelp = null;
+
+    /**
+     * A closure that does some custom validation on the setting before the setting is persisted.
+     *
+     * The closure should take two arguments: the setting value and the {@link Setting} instance being
+     * validated. If the value is found to be invalid, the closure should throw an exception with
+     * a message that describes the error.
+     *
+     * **Example**
+     *
+     *     $setting->validate = function ($value, Setting $setting) {
+     *         if ($value > 60) {
+     *             throw new \Exception('The time limit is not allowed to be greater than 60 minutes.');
+     *         }
+     *     }
+     *
+     * @var null|\Closure
+     */
+    public $validate = null;
+
+    /**
+     * A closure that transforms the setting value. If supplied, this closure will be executed after
+     * the setting has been validated.
+     *
+     * _Note: If a transform is supplied, the setting's {@link $type} has no effect. This means the
+     * transformation function will be responsible for casting the setting value to the appropriate
+     * data type._
+     *
+     * **Example**
+     *
+     *     $setting->transform = function ($value, Setting $setting) {
+     *         if ($value > 30) {
+     *             $value = 30;
+     *         }
+     *
+     *         return (int) $value;
+     *     }
+     *
+     * @var null|\Closure
+     */
+    public $transform = null;
+
+    /**
+     * This setting's display name, for example, `'Refresh Interval'`.
+     *
+     * Be sure to escape any user input as HTML can be used here.
+     *
+     * @var string
+     */
+    public $title = '';
+
+    /**
+     * Here you can define conditions so that certain form fields will be only shown when a certain condition
+     * is true. This condition is supposed to be evaluated on the client side dynamically. This way you can hide
+     * for example some fields depending on another field. For example if SiteSearch is disabled, fields to enter
+     * site search keywords is not needed anymore and can be disabled.
+     *
+     * For example 'sitesearch', or 'sitesearch && !use_sitesearch_default' where 'sitesearch' and 'use_sitesearch_default'
+     * are both values of fields.
+     *
+     * @var string
+     */
+    public $condition;
+
+}
diff --git a/core/Settings/Manager.php b/core/Settings/Manager.php
deleted file mode 100644
index e757e44d60..0000000000
--- a/core/Settings/Manager.php
+++ /dev/null
@@ -1,157 +0,0 @@
-<?php
-/**
- * Piwik - free/libre analytics platform
- *
- * @link http://piwik.org
- * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
- *
- */
-
-namespace Piwik\Settings;
-
-use Piwik\Plugin\Manager as PluginManager;
-
-/**
- * Settings manager.
- *
- */
-class Manager
-{
-    private static $settings = array();
-    private static $numPluginsChecked = 0;
-
-    /**
-     * Returns all available plugin settings, even settings for inactive plugins. A plugin has to specify a file named
-     * `Settings.php` containing a class named `Settings` that extends `Piwik\Plugin\Settings` in order to be
-     * considered as a plugin setting. Otherwise the settings for a plugin won't be available.
-     *
-     * @return \Piwik\Plugin\Settings[]   An array containing array([pluginName] => [setting instance]).
-     */
-    public static function getAllPluginSettings()
-    {
-        $numActivatedPlugins = PluginManager::getInstance()->getNumberOfActivatedPlugins();
-
-        if (static::$numPluginsChecked != $numActivatedPlugins) {
-            static::$numPluginsChecked = $numActivatedPlugins;
-            static::$settings = array();
-        }
-
-        if (empty(static::$settings)) {
-            $settings = PluginManager::getInstance()->findComponents('Settings', 'Piwik\\Plugin\\Settings');
-            $byPluginName = array();
-
-            foreach ($settings as $setting) {
-                $byPluginName[$setting->getPluginName()] = $setting;
-            }
-
-            static::$settings = $byPluginName;
-        }
-
-        return static::$settings;
-    }
-
-    private static function isActivatedPlugin($pluginName)
-    {
-        return PluginManager::getInstance()->isPluginActivated($pluginName);
-    }
-
-    /**
-     * Removes all settings made for a specific plugin. Useful while uninstalling a plugin.
-     *
-     * @param string $pluginName
-     */
-    public static function cleanupPluginSettings($pluginName)
-    {
-        $pluginManager = PluginManager::getInstance();
-
-        if (!$pluginManager->isPluginLoaded($pluginName)) {
-            return;
-        }
-
-        $plugin   = $pluginManager->loadPlugin($pluginName);
-        $settings = $plugin->findComponent('Settings', 'Piwik\\Plugin\\Settings');
-
-        if (!empty($settings)) {
-            $settings->removeAllPluginSettings();
-        }
-    }
-
-    /**
-     * Gets all plugins settings that have at least one settings a user is allowed to change. Only the settings for
-     * activated plugins are returned.
-     *
-     * @return \Piwik\Plugin\Settings[]   An array containing array([pluginName] => [setting instance]).
-     */
-    public static function getPluginSettingsForCurrentUser()
-    {
-        $settings = static::getAllPluginSettings();
-
-        $settingsForUser = array();
-        foreach ($settings as $pluginName => $setting) {
-            if (!static::isActivatedPlugin($pluginName)) {
-                continue;
-            }
-
-            $forUser = $setting->getSettingsForCurrentUser();
-            if (!empty($forUser)) {
-                $settingsForUser[$pluginName] = $setting;
-            }
-        }
-
-        return $settingsForUser;
-    }
-
-    public static function hasSystemPluginSettingsForCurrentUser($pluginName)
-    {
-        $pluginNames = static::getPluginNamesHavingSystemSettings();
-
-        return in_array($pluginName, $pluginNames);
-    }
-
-    /**
-     * Detects whether there are user settings for activated plugins available that the current user can change.
-     *
-     * @return bool
-     */
-    public static function hasUserPluginsSettingsForCurrentUser()
-    {
-        $settings = static::getPluginSettingsForCurrentUser();
-
-        foreach ($settings as $setting) {
-            foreach ($setting->getSettingsForCurrentUser() as $set) {
-                if ($set instanceof UserSetting) {
-                    return true;
-                }
-            }
-        }
-
-        return false;
-    }
-
-    public static function getPluginNamesHavingSystemSettings()
-    {
-        $settings = static::getPluginSettingsForCurrentUser();
-        $plugins  = array();
-
-        foreach ($settings as $pluginName => $setting) {
-            foreach ($setting->getSettingsForCurrentUser() as $set) {
-                if ($set instanceof SystemSetting) {
-                    $plugins[] = $pluginName;
-                }
-            }
-        }
-
-        return array_unique($plugins);
-    }
-    /**
-     * Detects whether there are system settings for activated plugins available that the current user can change.
-     *
-     * @return bool
-     */
-    public static function hasSystemPluginsSettingsForCurrentUser()
-    {
-        $settings = static::getPluginNamesHavingSystemSettings();
-
-        return !empty($settings);
-    }
-}
diff --git a/core/Settings/Measurable/MeasurableProperty.php b/core/Settings/Measurable/MeasurableProperty.php
new file mode 100644
index 0000000000..b49ee04698
--- /dev/null
+++ b/core/Settings/Measurable/MeasurableProperty.php
@@ -0,0 +1,89 @@
+<?php
+/**
+ * Piwik - free/libre analytics platform
+ *
+ * @link http://piwik.org
+ * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
+ *
+ */
+
+namespace Piwik\Settings\Measurable;
+
+use Piwik\Container\StaticContainer;
+use Piwik\Piwik;
+use Piwik\Settings\Storage;
+use Exception;
+
+/**
+ * Describes a Measurable property for a measurable type such as a website, a mobile app, ....
+ *
+ * The difference to {@link MeasurableSetting} is that these fields will be stored in the actual site table whereas
+ * MeasurableSetting will be stored in a site_settings table. For this reasons MeasurableProperty can be used only
+ * for some specific fields that already exist in site table such as "ecommerce", "sitesearch" etc.
+ *
+ * See {@link \Piwik\Settings\Setting}.
+ */
+class MeasurableProperty extends \Piwik\Settings\Setting
+{
+    /**
+     * @var int
+     */
+    private $idSite = 0;
+
+    private $allowedNames = array(
+        'ecommerce', 'sitesearch', 'sitesearch_keyword_parameters',
+        'sitesearch_category_parameters',
+        'exclude_unknown_urls', 'excluded_ips', 'excluded_parameters',
+        'excluded_user_agents', 'keep_url_fragment', 'urls'
+    );
+
+    /**
+     * Constructor.
+     *
+     * @param string $name The persisted name of the setting.
+     * @param mixed $defaultValue  Default value for this setting if no value was specified.
+     * @param string $type Eg an array, int, ... see TYPE_* constants
+     * @param string $pluginName The name of the plugin the setting belongs to.
+     * @param int $idSite The idSite this property belongs to.
+     * @throws Exception
+     */
+    public function __construct($name, $defaultValue, $type, $pluginName, $idSite)
+    {
+        if (!in_array($name, $this->allowedNames)) {
+            throw new Exception(sprintf('Name "%s" is not allowed to be used with a MeasurableProperty, use a MeasurableSetting instead.', $name));
+        }
+
+        parent::__construct($name, $defaultValue, $type, $pluginName);
+
+        $this->idSite = $idSite;
+
+        $storageFactory = StaticContainer::get('Piwik\Settings\Storage\Factory');
+        $this->storage = $storageFactory->getSitesTable($idSite);
+    }
+
+    /**
+     * Returns `true` if this setting can be displayed for the current user, `false` if otherwise.
+     *
+     * @return bool
+     */
+    public function isWritableByCurrentUser()
+    {
+        if (isset($this->hasWritePermission)) {
+            return $this->hasWritePermission;
+        }
+
+        // performance improvement, do not detect this in __construct otherwise likely rather "big" query to DB.
+        if ($this->hasSiteBeenCreated()) {
+            $this->hasWritePermission = Piwik::isUserHasAdminAccess($this->idSite);
+        } else {
+            $this->hasWritePermission = Piwik::hasUserSuperUserAccess();
+        }
+
+        return $this->hasWritePermission;
+    }
+
+    private function hasSiteBeenCreated()
+    {
+        return !empty($this->idSite);
+    }
+}
diff --git a/core/Settings/Measurable/MeasurableSetting.php b/core/Settings/Measurable/MeasurableSetting.php
new file mode 100644
index 0000000000..b03289e44e
--- /dev/null
+++ b/core/Settings/Measurable/MeasurableSetting.php
@@ -0,0 +1,72 @@
+<?php
+/**
+ * Piwik - free/libre analytics platform
+ *
+ * @link http://piwik.org
+ * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
+ *
+ */
+
+namespace Piwik\Settings\Measurable;
+
+use Piwik\Container\StaticContainer;
+use Piwik\Piwik;
+use Piwik\Settings\Storage;
+
+/**
+ * Describes a Measurable setting for a measurable type such as a website, a mobile app, ...
+ *
+ * See {@link \Piwik\Settings\Setting}.
+ */
+class MeasurableSetting extends \Piwik\Settings\Setting
+{
+    /**
+     * @var int
+     */
+    private $idSite = 0;
+
+    /**
+     * Constructor.
+     *
+     * @param string $name The persisted name of the setting.
+     * @param mixed $defaultValue  Default value for this setting if no value was specified.
+     * @param string $type Eg an array, int, ... see TYPE_* constants
+     * @param string $pluginName The name of the plugin the setting belongs to
+     * @param int $idSite The idSite this setting belongs to.
+     */
+    public function __construct($name, $defaultValue, $type, $pluginName, $idSite)
+    {
+        parent::__construct($name, $defaultValue, $type, $pluginName);
+
+        $this->idSite = $idSite;
+
+        $storageFactory = StaticContainer::get('Piwik\Settings\Storage\Factory');
+        $this->storage = $storageFactory->getMeasurableSettingsStorage($idSite, $this->pluginName);
+    }
+
+    /**
+     * Returns `true` if this setting can be displayed for the current user, `false` if otherwise.
+     *
+     * @return bool
+     */
+    public function isWritableByCurrentUser()
+    {
+        if (isset($this->hasWritePermission)) {
+            return $this->hasWritePermission;
+        }
+
+        // performance improvement, do not detect this in __construct otherwise likely rather "big" query to DB.
+        if ($this->hasSiteBeenCreated()) {
+            $this->hasWritePermission = Piwik::isUserHasAdminAccess($this->idSite);
+        } else {
+            $this->hasWritePermission = Piwik::hasUserSuperUserAccess();
+        }
+
+        return $this->hasWritePermission;
+    }
+
+    private function hasSiteBeenCreated()
+    {
+        return !empty($this->idSite);
+    }
+}
diff --git a/core/Settings/Measurable/MeasurableSettings.php b/core/Settings/Measurable/MeasurableSettings.php
new file mode 100644
index 0000000000..3d062f9943
--- /dev/null
+++ b/core/Settings/Measurable/MeasurableSettings.php
@@ -0,0 +1,141 @@
+<?php
+/**
+ * Piwik - free/libre analytics platform
+ *
+ * @link http://piwik.org
+ * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
+ *
+ */
+namespace Piwik\Settings\Measurable;
+
+use Piwik\Db;
+use Piwik\Piwik;
+use Piwik\Settings\Settings;
+use Piwik\Settings\Storage;
+use Piwik\Site;
+use Exception;
+
+/**
+ * Base class of all measurable settings providers. Plugins that define their own configuration settings
+ * can extend this class to easily make their measurable settings available to Piwik users.
+ *
+ * Descendants of this class should implement the {@link init()} method and call the
+ * {@link makeSetting()} method for each of the measurable's settings.
+ *
+ * For an example, see the {@link Piwik\Plugins\ExampleSettingsPlugin\MeasurableSettings} plugin.
+ *
+ * $settingsProvider   = new Piwik\Plugin\SettingsProvider(); // get this instance via dependency injection
+ * $measurableSettings = $settingProvider->getMeasurableSettings($yourPluginName, $idsite, $idType = null);
+ * $measurableSettings->yourSetting->getValue();
+ *
+ * @api
+ */
+abstract class MeasurableSettings extends Settings
+{
+    /**
+     * @var int
+     */
+    protected $idSite;
+
+    /**
+     * @var string
+     */
+    protected $idMeasurableType;
+
+    /**
+     * Constructor.
+     * @param int $idSite If creating settings for a new site that is not created yet, use idSite = 0
+     * @param string|null $idMeasurableType If null, idType will be detected from idSite
+     * @throws Exception
+     */
+    public function __construct($idSite, $idMeasurableType = null)
+    {
+        parent::__construct();
+
+        $this->idSite = (int) $idSite;
+
+        if (!empty($idMeasurableType)) {
+            $this->idMeasurableType = $idMeasurableType;
+        } elseif (!empty($idSite)) {
+            $this->idMeasurableType = Site::getTypeFor($idSite);
+        } else {
+            throw new Exception('No idType specified for ' . get_class($this));
+        }
+
+        $this->init();
+    }
+
+    protected function hasMeasurableType($typeId)
+    {
+        return $typeId === $this->idMeasurableType;
+    }
+
+    /**
+     * Creates a new measurable setting.
+     *
+     * Settings will be displayed in the UI depending on the order of `makeSetting` calls. This means you can define
+     * the order of the displayed settings by calling makeSetting first for more important settings.
+     *
+     * @param string $name         The name of the setting that shall be created
+     * @param mixed  $defaultValue The default value for this setting. Note the value will not be converted to the
+     *                             specified type.
+     * @param string $type         The PHP internal type the value of this setting should have.
+     *                             Use one of FieldConfig::TYPE_* constancts
+     * @param \Closure $fieldConfigCallback   A callback method to configure the field that shall be displayed in the
+     *                             UI to define the value for this setting
+     * @return MeasurableSetting   Returns an instance of the created measurable setting.
+     * @throws Exception
+     */
+    protected function makeSetting($name, $defaultValue, $type, $fieldConfigCallback)
+    {
+        $setting = new MeasurableSetting($name, $defaultValue, $type, $this->pluginName, $this->idSite);
+        $setting->setConfigureCallback($fieldConfigCallback);
+
+        $this->addSetting($setting);
+
+        return $setting;
+    }
+
+    /**
+     * @internal
+     * @param $name
+     * @param $defaultValue
+     * @param $type
+     * @param $configureCallback
+     * @return MeasurableProperty
+     * @throws Exception
+     */
+    protected function makeProperty($name, $defaultValue, $type, $configureCallback)
+    {
+        $setting = new MeasurableProperty($name, $defaultValue, $type, $this->pluginName, $this->idSite);
+        $setting->setConfigureCallback($configureCallback);
+
+        $this->addSetting($setting);
+
+        return $setting;
+    }
+
+    /**
+     * Saves (persists) the current measurable setting values in the database.
+     *
+     * Will trigger an event to notify plugins that a value has been changed.
+     */
+    public function save()
+    {
+        parent::save();
+
+        /**
+         * Triggered after a plugin settings have been updated.
+         *
+         * **Example**
+         *
+         *     Piwik::addAction('MeasurableSettings.updated', function (MeasurableSettings $settings) {
+         *         $value = $settings->someSetting->getValue();
+         *         // Do something with the new setting value
+         *     });
+         *
+         * @param Settings $settings The plugin settings object.
+         */
+        Piwik::postEvent('MeasurableSettings.updated', array($this, $this->idSite));
+    }
+}
diff --git a/core/Settings/SystemSetting.php b/core/Settings/Plugin/SystemSetting.php
index 68e780a3e8..3c10a4c5f4 100644
--- a/core/Settings/SystemSetting.php
+++ b/core/Settings/Plugin/SystemSetting.php
@@ -7,48 +7,38 @@
  *
  */
 
-namespace Piwik\Settings;
+namespace Piwik\Settings\Plugin;
 
 use Piwik\Config;
+use Piwik\Container\StaticContainer;
 use Piwik\Piwik;
+use Piwik\Settings\Setting;
+use Piwik\Settings\Storage;
 
 /**
- * Describes a system wide setting. Only the Super User can change this type of setting and
+ * Describes a system wide setting. Only the Super User can change this type of setting by d efault and
  * the value of this setting will affect all users.
  *
- * See {@link \Piwik\Plugin\Settings}.
- *
+ * See {@link \Piwik\Settings\Setting}.
  *
  * @api
  */
 class SystemSetting extends Setting
 {
     /**
-     * By default the value of the system setting is only readable by SuperUsers but someone the value should be
-     * readable by everyone.
-     *
-     * @var bool
-     * @since 2.4.0
-     */
-    public $readableByCurrentUser = false;
-
-    /**
-     * @var bool
-     */
-    private $writableByCurrentUser = false;
-
-    /**
      * Constructor.
      *
-     * @param string $name The persisted name of the setting.
-     * @param string $title The display name of the setting.
+     * @param string $name The setting's persisted name.
+     * @param mixed $defaultValue  Default value for this setting if no value was specified.
+     * @param string $type Eg an array, int, ... see TYPE_* constants
+     * @param string $pluginName The name of the plugin the system setting belongs to.
      */
-    public function __construct($name, $title)
+    public function __construct($name, $defaultValue, $type, $pluginName)
     {
-        parent::__construct($name, $title);
+        parent::__construct($name, $defaultValue, $type, $pluginName);
 
-        $this->writableByCurrentUser = Piwik::hasUserSuperUserAccess();
-        $this->readableByCurrentUser = $this->writableByCurrentUser;
+        $factory = StaticContainer::get('Piwik\Settings\Storage\Factory');
+        $this->storage = $factory->getPluginStorage($this->pluginName, $userLogin = '');
     }
 
     /**
@@ -63,39 +53,19 @@ class SystemSetting extends Setting
             return false;
         }
 
-        return $this->writableByCurrentUser;
-    }
+        if (isset($this->hasWritePermission)) {
+            return $this->hasWritePermission;
+        }
 
-    /**
-     * Set whether setting is writable or not. For example to hide setting from the UI set it to false.
-     *
-     * @param bool $isWritable
-     */
-    public function setIsWritableByCurrentUser($isWritable)
-    {
-        $this->writableByCurrentUser = (bool) $isWritable;
-    }
+        // performance improvement, do not detect this in __construct otherwise likely rather "big" query to DB.
+        $this->hasWritePermission = Piwik::hasUserSuperUserAccess();
 
-    /**
-     * Returns `true` if this setting can be displayed for the current user, `false` if otherwise.
-     *
-     * @return bool
-     */
-    public function isReadableByCurrentUser()
-    {
-        return $this->readableByCurrentUser;
+        return $this->hasWritePermission;
     }
 
     /**
-     * Returns the display order. System settings are displayed before user settings.
-     *
-     * @return int
+     * @inheritdoc
      */
-    public function getOrder()
-    {
-        return 30;
-    }
-
     public function getValue()
     {
         $defaultValue = parent::getValue(); // we access value first to make sure permissions are checked
diff --git a/core/Settings/Plugin/SystemSettings.php b/core/Settings/Plugin/SystemSettings.php
new file mode 100644
index 0000000000..1b2fc413ff
--- /dev/null
+++ b/core/Settings/Plugin/SystemSettings.php
@@ -0,0 +1,90 @@
+<?php
+/**
+ * Piwik - free/libre analytics platform
+ *
+ * @link http://piwik.org
+ * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
+ *
+ */
+namespace Piwik\Settings\Plugin;
+
+use Piwik\Db;
+use Piwik\Piwik;
+use Piwik\Settings\Settings;
+use Piwik\Settings\Storage;
+
+/**
+ * Base class of all system settings providers. Plugins that define their own configuration settings
+ * can extend this class to easily make their system settings available to Piwik users.
+ *
+ * Descendants of this class should implement the {@link init()} method and call the
+ * {@link makeSetting()} method to create a system setting for this plugin.
+ *
+ * For an example, see {@link Piwik\Plugins\ExampleSettingsPlugin\SystemSettings}.
+ *
+ * $systemSettings = new Piwik\Plugins\ExampleSettingsPlugin\SystemSettings(); // get instance via dependency injection
+ * $systemSettings->yourSetting->getValue();
+ *
+ * @api
+ */
+abstract class SystemSettings extends Settings
+{
+    /**
+     * Constructor.
+     */
+    public function __construct()
+    {
+        parent::__construct();
+
+        $this->init();
+    }
+
+    /**
+     * Creates a new system setting.
+     *
+     * Settings will be displayed in the UI depending on the order of `makeSetting` calls. This means you can define
+     * the order of the displayed settings by calling makeSetting first for more important settings.
+     *
+     * @param string $name         The name of the setting that shall be created
+     * @param mixed  $defaultValue The default value for this setting. Note the value will not be converted to the
+     *                             specified type.
+     * @param string $type         The PHP internal type the value of this setting should have.
+     *                             Use one of FieldConfig::TYPE_* constancts
+     * @param \Closure $fieldConfigCallback   A callback method to configure the field that shall be displayed in the
+     *                             UI to define the value for this setting
+     * @return SystemSetting   Returns an instance of the created measurable setting.
+     */
+    protected function makeSetting($name, $defaultValue, $type, $fieldConfigCallback)
+    {
+        $setting = new SystemSetting($name, $defaultValue, $type, $this->pluginName);
+        $setting->setConfigureCallback($fieldConfigCallback);
+        $this->addSetting($setting);
+        return $setting;
+    }
+
+    /**
+     * Saves (persists) the current setting values in the database.
+     *
+     * Will trigger an event to notify plugins that a value has been changed.
+     */
+    public function save()
+    {
+        parent::save();
+
+        /**
+         * Triggered after system settings have been updated.
+         *
+         * **Example**
+         *
+         *     Piwik::addAction('SystemSettings.updated', function (SystemSettings $settings) {
+         *         if ($settings->getPluginName() === 'PluginName') {
+         *             $value = $settings->someSetting->getValue();
+         *             // Do something with the new setting value
+         *         }
+         *     });
+         *
+         * @param Settings $settings The plugin settings object.
+         */
+        Piwik::postEvent('SystemSettings.updated', array($this));
+    }
+}
diff --git a/core/Settings/Plugin/UserSetting.php b/core/Settings/Plugin/UserSetting.php
new file mode 100644
index 0000000000..0044eef78f
--- /dev/null
+++ b/core/Settings/Plugin/UserSetting.php
@@ -0,0 +1,73 @@
+<?php
+/**
+ * Piwik - free/libre analytics platform
+ *
+ * @link http://piwik.org
+ * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
+ *
+ */
+
+namespace Piwik\Settings\Plugin;
+
+use Piwik\Container\StaticContainer;
+use Piwik\Db;
+use Piwik\Piwik;
+use Exception;
+use Piwik\Settings\Setting;
+use Piwik\Settings\Storage;
+
+/**
+ * Describes a per user setting. Each user will be able to change this setting for themselves,
+ * but not for other users.
+ *
+ * See {@link \Piwik\Settings\Setting}.
+ */
+class UserSetting extends Setting
+{
+    /**
+     * @var null|string
+     */
+    private $userLogin = null;
+
+    /**
+     * Constructor.
+     *
+     * @param string $name The setting's persisted name.
+     * @param mixed $defaultValue  Default value for this setting if no value was specified.
+     * @param string $type Eg an array, int, ... see TYPE_* constants
+     * @param string $pluginName The name of the plugin the setting belongs to
+     * @param string $userLogin The name of the user the value should be set or get for
+     * @throws Exception
+     */
+    public function __construct($name, $defaultValue, $type, $pluginName, $userLogin)
+    {
+        parent::__construct($name, $defaultValue, $type, $pluginName);
+
+        if (empty($userLogin)) {
+            throw new Exception('No userLogin given to create setting ' . $name);
+        }
+
+        $this->userLogin = $userLogin;
+
+        $factory = StaticContainer::get('Piwik\Settings\Storage\Factory');
+        $this->storage = $factory->getPluginStorage($this->pluginName, $this->userLogin);
+    }
+
+    /**
+     * Returns `true` if this setting can be displayed for the current user, `false` if otherwise.
+     *
+     * @return bool
+     */
+    public function isWritableByCurrentUser()
+    {
+        if (isset($this->hasWritePermission)) {
+            return $this->hasWritePermission;
+        }
+
+        // performance improvement, do not detect this in __construct otherwise likely rather "big" query to DB.
+        $this->hasWritePermission = Piwik::isUserHasSomeViewAccess();
+
+        return $this->hasWritePermission;
+    }
+
+}
diff --git a/core/Settings/Plugin/UserSettings.php b/core/Settings/Plugin/UserSettings.php
new file mode 100644
index 0000000000..cda8438d73
--- /dev/null
+++ b/core/Settings/Plugin/UserSettings.php
@@ -0,0 +1,93 @@
+<?php
+/**
+ * Piwik - free/libre analytics platform
+ *
+ * @link http://piwik.org
+ * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
+ *
+ */
+namespace Piwik\Settings\Plugin;
+
+use Piwik\Db;
+use Piwik\Piwik;
+use Piwik\Settings\Settings;
+use Piwik\Settings\Storage;
+
+/**
+ * Base class of all plugin settings providers. Plugins that define their own configuration settings
+ * can extend this class to easily make their settings available to Piwik users.
+ *
+ * Descendants of this class should implement the {@link init()} method and call the
+ * {@link addSetting()} method for each of the plugin's settings.
+ *
+ * For an example, see {@link Piwik\Plugins\ExampleSettingsPlugin\UserSettings}.
+ *
+ * $userSettings = new Piwik\Plugins\ExampleSettingsPlugin\UserSettings(); // get instance via dependency injection
+ * $userSettings->yourSetting->getValue();
+ *
+ * @api
+ */
+abstract class UserSettings extends Settings
+{
+    /**
+     * Constructor.
+     */
+    public function __construct()
+    {
+        parent::__construct();
+
+        $this->init();
+    }
+
+    /**
+     * Creates a new user setting.
+     *
+     * Settings will be displayed in the UI depending on the order of `makeSetting` calls. This means you can define
+     * the order of the displayed settings by calling makeSetting first for more important settings.
+     *
+     * @param string $name         The name of the setting that shall be created
+     * @param mixed  $defaultValue The default value for this setting. Note the value will not be converted to the
+     *                             specified type.
+     * @param string $type         The PHP internal type the value of this setting should have.
+     *                             Use one of FieldConfig::TYPE_* constancts
+     * @param \Closure $fieldConfigCallback   A callback method to configure the field that shall be displayed in the
+     *                             UI to define the value for this setting
+     * @return UserSetting   Returns an instance of the created measurable setting.
+     */
+    protected function makeSetting($name, $defaultValue, $type, $configureCallback)
+    {
+        $userLogin = Piwik::getCurrentUserLogin();
+
+        $setting = new UserSetting($name, $defaultValue, $type, $this->pluginName, $userLogin);
+        $setting->setConfigureCallback($configureCallback);
+
+        $this->addSetting($setting);
+        return $setting;
+    }
+
+    /**
+     * Saves (persists) the current setting values in the database.
+     *
+     * Will trigger an event to notify plugins that a value has been changed.
+     */
+    public function save()
+    {
+        parent::save();
+
+        /**
+         * Triggered after user settings have been updated.
+         *
+         * **Example**
+         *
+         *     Piwik::addAction('UserSettings.updated', function (UserSettings $settings) {
+         *         if ($settings->getPluginName() === 'PluginName') {
+         *             $value = $settings->someSetting->getValue();
+         *             // Do something with the new setting value
+         *         }
+         *     });
+         *
+         * @param Settings $settings The plugin settings object.
+         */
+        Piwik::postEvent('UserSettings.updated', array($this));
+    }
+}
diff --git a/core/Settings/Setting.php b/core/Settings/Setting.php
index bf8947b196..efd99c3802 100644
--- a/core/Settings/Setting.php
+++ b/core/Settings/Setting.php
@@ -10,168 +10,84 @@
 namespace Piwik\Settings;
 
 use Piwik\Piwik;
-use Piwik\SettingsServer;
+use Piwik\Settings\Storage\Storage;
+use Exception;
 
 /**
  * Base setting type class.
  *
  * @api
  */
-abstract class Setting
+class Setting
 {
-    /**
-     * Describes the setting's PHP data type. When saved, setting values will always be casted to this
-     * type.
-     *
-     * See {@link Piwik\Plugin\Settings} for a list of supported data types.
-     *
-     * @var string
-     */
-    public $type = null;
 
     /**
-     * Describes what HTML element should be used to manipulate the setting through Piwik's UI.
-     *
-     * See {@link Piwik\Plugin\Settings} for a list of supported control types.
-     *
+     * The name of the setting
      * @var string
      */
-    public $uiControlType = null;
-
-    /**
-     * Name-value mapping of HTML attributes that will be added HTML form control, eg,
-     * `array('size' => 3)`. Attributes will be escaped before outputting.
-     *
-     * @var array
-     */
-    public $uiControlAttributes = array();
-
-    /**
-     * The list of all available values for this setting. If null, the setting can have any value.
-     *
-     * If supplied, this field should be an array mapping available values with their prettified
-     * display value. Eg, if set to `array('nb_visits' => 'Visits', 'nb_actions' => 'Actions')`,
-     * the UI will display **Visits** and **Actions**, and when the user selects one, Piwik will
-     * set the setting to **nb_visits** or **nb_actions** respectively.
-     *
-     * The setting value will be validated if this field is set. If the value is not one of the
-     * available values, an error will be triggered.
-     *
-     * _Note: If a custom validator is supplied (see {@link $validate}), the setting value will
-     * not be validated._
-     *
-     * @var null|array
-     */
-    public $availableValues = null;
+    protected $name;
 
     /**
-     * Text that will appear above this setting's section in the _Plugin Settings_ admin page.
-     *
-     * @var null|string
+     * Null while not initialized, bool otherwise.
+     * @var null|bool
      */
-    public $introduction    = null;
+    protected $hasWritePermission = null;
 
     /**
-     * Text that will appear directly underneath the setting title in the _Plugin Settings_ admin
-     * page. If set, should be a short description of the setting.
-     *
-     * @var null|string
+     * @var Storage
      */
-    public $description     = null;
+    protected $storage;
 
     /**
-     * Text that will appear next to the setting's section in the _Plugin Settings_ admin page. If set,
-     * it should contain information about the setting that is more specific than a general description,
-     * such as the format of the setting value if it has a special format.
-     *
-     * @var null|string
+     * @var string
      */
-    public $inlineHelp      = null;
+    protected $pluginName;
 
     /**
-     * A closure that does some custom validation on the setting before the setting is persisted.
-     *
-     * The closure should take two arguments: the setting value and the {@link Setting} instance being
-     * validated. If the value is found to be invalid, the closure should throw an exception with
-     * a message that describes the error.
-     *
-     * **Example**
-     *
-     *     $setting->validate = function ($value, Setting $setting) {
-     *         if ($value > 60) {
-     *             throw new \Exception('The time limit is not allowed to be greater than 60 minutes.');
-     *         }
-     *     }
-     *
-     * @var null|\Closure
+     * @var FieldConfig
      */
-    public $validate        = null;
+    protected $config;
 
     /**
-     * A closure that transforms the setting value. If supplied, this closure will be executed after
-     * the setting has been validated.
-     *
-     * _Note: If a transform is supplied, the setting's {@link $type} has no effect. This means the
-     * transformation function will be responsible for casting the setting value to the appropriate
-     * data type._
-     *
-     * **Example**
-     *
-     *     $setting->transform = function ($value, Setting $setting) {
-     *         if ($value > 30) {
-     *             $value = 30;
-     *         }
-     *
-     *         return (int) $value;
-     *     }
-     *
-     * @var null|\Closure
+     * @var \Closure|null
      */
-    public $transform          = null;
+    protected $configureCallback;
 
     /**
-     * Default value of this setting.
-     *
-     * The default value is not casted to the appropriate data type. This means _**you**_ have to make
-     * sure the value is of the correct type.
-     *
      * @var mixed
      */
-    public $defaultValue    = null;
+    protected $defaultValue;
 
     /**
-     * This setting's display name, for example, `'Refresh Interval'`.
-     *
      * @var string
      */
-    public $title           = '';
-
-    protected $key;
-    protected $name;
-
-    /**
-     * @var StorageInterface
-     */
-    private $storage;
-    protected $pluginName;
+    protected $type;
 
     /**
      * Constructor.
      *
      * @param string $name    The setting's persisted name. Only alphanumeric characters are allowed, eg,
      *                        `'refreshInterval'`.
-     * @param string $title   The setting's display name, eg, `'Refresh Interval'`.
+     * @param mixed $defaultValue  Default value for this setting if no value was specified.
+     * @param string $type Eg an array, int, ... see SettingConfig::TYPE_* constants
+     * @param string $pluginName   The name of the plugin the setting belongs to
+     * @throws Exception
      */
-    public function __construct($name, $title)
+    public function __construct($name, $defaultValue, $type, $pluginName)
     {
-        $this->key   = $name;
-        $this->name  = $name;
-        $this->title = $title;
+        if (!ctype_alnum(str_replace('_', '', $name))) {
+            $msg = sprintf('The setting name "%s" in plugin "%s" is invalid. Only underscores, alpha and numerical characters are allowed', $name, $pluginName);
+            throw new Exception($msg);
+        }
+
+        $this->name = $name;
+        $this->type = $type;
+        $this->pluginName = $pluginName;
+        $this->setDefaultValue($defaultValue);
     }
 
     /**
-     * Returns the setting's persisted name, eg, `'refreshInterval'`.
-     *
+     * Get the name of the setting.
      * @return string
      */
     public function getName()
@@ -180,32 +96,47 @@ abstract class Setting
     }
 
     /**
-     * Returns `true` if this setting is writable for the current user, `false` if otherwise. In case it returns
-     * writable for the current user it will be visible in the Plugin settings UI.
-     *
-     * @return bool
+     * Get the PHP type of the setting.
+     * @return string
      */
-    public function isWritableByCurrentUser()
+    public function getType()
     {
-        return false;
+        return $this->type;
     }
 
     /**
-     * Returns `true` if this setting can be displayed for the current user, `false` if otherwise.
-     *
-     * @return bool
+     * @internal
+     * @ignore
+     * @param $callback
      */
-    public function isReadableByCurrentUser()
+    public function setConfigureCallback($callback)
     {
-        return false;
+        $this->configureCallback = $callback;
+        $this->config = null;
     }
 
     /**
-     * Sets the object used to persist settings.
-     *
-     * @param StorageInterface $storage
+     * @return mixed
+     */
+    public function getDefaultValue()
+    {
+        return $this->defaultValue;
+    }
+
+    /**
+     * Sets/overwrites the current default value
+     * @param string $defaultValue
      */
-    public function setStorage(StorageInterface $storage)
+    public function setDefaultValue($defaultValue)
+    {
+        $this->defaultValue = $defaultValue;
+    }
+
+    /**
+     * @internal
+     * @param Storage $storage
+     */
+    public function setStorage(Storage $storage)
     {
         $this->storage = $storage;
     }
@@ -213,35 +144,52 @@ abstract class Setting
     /**
      * @internal
      * @ignore
-     * @return StorageInterface
+     * @return FieldConfig
+     * @throws Exception
      */
-    public function getStorage()
+    public function configureField()
     {
-        return $this->storage;
+        if (!$this->config) {
+            $this->config = new FieldConfig();
+
+            if ($this->configureCallback) {
+                call_user_func($this->configureCallback, $this->config);
+            }
+
+            $this->setUiControlIfNeeded($this->config);
+            $this->checkType($this->config);
+        }
+
+        return $this->config;
     }
 
     /**
-     * Sets th name of the plugin the setting belongs to
+     * Set whether setting is writable or not. For example to hide setting from the UI set it to false.
      *
-     * @param string $pluginName
+     * @param bool $isWritable
      */
-    public function setPluginName($pluginName)
+    public function setIsWritableByCurrentUser($isWritable)
     {
-        $this->pluginName = $pluginName;
+        $this->hasWritePermission = (bool) $isWritable;
     }
 
     /**
-     * Returns the previously persisted setting value. If no value was set, the default value
-     * is returned.
+     * Returns `true` if this setting is writable for the current user, `false` if otherwise. In case it returns
+     * writable for the current user it will be visible in the Plugin settings UI.
      *
-     * @return mixed
-     * @throws \Exception If the current user is not allowed to change the value of this setting.
+     * @return bool
      */
-    public function getValue()
+    public function isWritableByCurrentUser()
     {
-        $this->checkHasEnoughReadPermission();
+        return (bool) $this->hasWritePermission;
+    }
 
-        return $this->storage->getValue($this);
+    /**
+     * Saves (persists) the value for this setting in the database if a value has been actually set.
+     */
+    public function save()
+    {
+        $this->storage->save();
     }
 
     /**
@@ -249,40 +197,85 @@ abstract class Setting
      * is returned.
      *
      * @return mixed
-     * @throws \Exception If the current user is not allowed to change the value of this setting.
      */
-    public function removeValue()
+    public function getValue()
     {
-        $this->checkHasEnoughWritePermission();
-
-        return $this->storage->deleteValue($this);
+        return $this->storage->getValue($this->name, $this->defaultValue, $this->type);
     }
 
     /**
      * Sets and persists this setting's value overwriting any existing value.
      *
+     * Before a value is actually set it will be made sure the current user is allowed to change the value. The value
+     * will be first validated either via a system built-in validate method or via a set {@link FieldConfig::$validate}
+     * custom method. Afterwards the value will be transformed via a possibly specified {@link FieldConfig::$transform}
+     * method. Before storing the actual value, the value will be converted to the actually specified {@link $type}.
+     *
      * @param mixed $value
      * @throws \Exception If the current user is not allowed to change the value of this setting.
      */
     public function setValue($value)
     {
+        $this->checkHasEnoughWritePermission();
+
+        $config = $this->configureField();
+
         $this->validateValue($value);
 
-        if ($this->transform && $this->transform instanceof \Closure) {
-            $value = call_user_func($this->transform, $value, $this);
-        } elseif (isset($this->type)) {
+        if ($config->transform && $config->transform instanceof \Closure) {
+            $value = call_user_func($config->transform, $value, $this);
+        }
+
+        if (isset($this->type)) {
             settype($value, $this->type);
         }
 
-        return $this->storage->setValue($this, $value);
+        $this->storage->setValue($this->name, $value);
     }
 
     private function validateValue($value)
     {
-        $this->checkHasEnoughWritePermission();
-
-        if ($this->validate && $this->validate instanceof \Closure) {
-            call_user_func($this->validate, $value, $this);
+        $config = $this->configureField();
+
+        if ($config->validate && $config->validate instanceof \Closure) {
+            call_user_func($config->validate, $value, $this);
+        } elseif (is_array($config->availableValues)) {
+            if (is_bool($value) && $value) {
+                $value = '1';
+            } elseif (is_bool($value)) {
+                $value = '0';
+            }
+
+            // TODO move error message creation to a subclass, eg in MeasurableSettings we do not want to mention plugin name
+            $errorMsg = Piwik::translate('CoreAdminHome_PluginSettingsValueNotAllowed',
+                                         array(strip_tags($config->title), $this->pluginName));
+
+            if (is_array($value) && $this->type === FieldConfig::TYPE_ARRAY) {
+                foreach ($value as $val) {
+                    if (!array_key_exists($val, $config->availableValues)) {
+                        throw new \Exception($errorMsg);
+                    }
+                }
+            } else {
+                if (!array_key_exists($value, $config->availableValues)) {
+                    throw new \Exception($errorMsg);
+                }
+            }
+        } elseif ($this->type === FieldConfig::TYPE_INT || $this->type === FieldConfig::TYPE_FLOAT) {
+
+            if (!is_numeric($value)) {
+                $errorMsg = Piwik::translate('CoreAdminHome_PluginSettingsValueNotAllowed',
+                                             array(strip_tags($config->title), $this->pluginName));
+                throw new \Exception($errorMsg);
+            }
+
+        } elseif ($this->type === FieldConfig::TYPE_BOOL) {
+
+            if (!in_array($value, array(true, false, '0', '1', 0, 1), true)) {
+                $errorMsg = Piwik::translate('CoreAdminHome_PluginSettingsValueNotAllowed',
+                                             array(strip_tags($config->title), $this->pluginName));
+                throw new \Exception($errorMsg);
+            }
         }
     }
 
@@ -291,50 +284,49 @@ abstract class Setting
      */
     private function checkHasEnoughWritePermission()
     {
-        // When the request is a Tracker request, allow plugins to write settings
-        if (SettingsServer::isTrackerApiRequest()) {
-            return;
-        }
-
         if (!$this->isWritableByCurrentUser()) {
-            $errorMsg = Piwik::translate('CoreAdminHome_PluginSettingChangeNotAllowed', array($this->getName(), $this->pluginName));
+            $errorMsg = Piwik::translate('CoreAdminHome_PluginSettingChangeNotAllowed', array($this->name, $this->pluginName));
             throw new \Exception($errorMsg);
         }
     }
 
-    /**
-     * @throws \Exception
-     */
-    private function checkHasEnoughReadPermission()
+    private function setUiControlIfNeeded(FieldConfig $field)
     {
-        // When the request is a Tracker request, allow plugins to read settings
-        if (SettingsServer::isTrackerApiRequest()) {
-            return;
-        }
-
-        if (!$this->isReadableByCurrentUser()) {
-            $errorMsg = Piwik::translate('CoreAdminHome_PluginSettingReadNotAllowed', array($this->getName(), $this->pluginName));
-            throw new \Exception($errorMsg);
+        if (!isset($field->uiControl)) {
+            $defaultControlTypes = array(
+                FieldConfig::TYPE_INT    => FieldConfig::UI_CONTROL_TEXT,
+                FieldConfig::TYPE_FLOAT  => FieldConfig::UI_CONTROL_TEXT,
+                FieldConfig::TYPE_STRING => FieldConfig::UI_CONTROL_TEXT,
+                FieldConfig::TYPE_BOOL   => FieldConfig::UI_CONTROL_CHECKBOX,
+                FieldConfig::TYPE_ARRAY  => FieldConfig::UI_CONTROL_MULTI_SELECT,
+            );
+
+            if (isset($defaultControlTypes[$this->type])) {
+                $field->uiControl = $defaultControlTypes[$this->type];
+            } else {
+                $field->uiControl = FieldConfig::UI_CONTROL_TEXT;
+            }
         }
     }
 
-    /**
-     * Returns the unique string key used to store this setting.
-     *
-     * @return string
-     */
-    public function getKey()
+    private function checkType(FieldConfig $field)
     {
-        return $this->key;
-    }
+        if ($field->uiControl === FieldConfig::UI_CONTROL_MULTI_SELECT &&
+            $this->type !== FieldConfig::TYPE_ARRAY) {
+            throw new Exception('Type must be an array when using a multi select');
+        }
 
-    /**
-     * Returns the display order. The lower the return value, the earlier the setting will be displayed.
-     *
-     * @return int
-     */
-    public function getOrder()
-    {
-        return 100;
+        $types = array(
+            FieldConfig::TYPE_INT,
+            FieldConfig::TYPE_FLOAT,
+            FieldConfig::TYPE_STRING,
+            FieldConfig::TYPE_BOOL,
+            FieldConfig::TYPE_ARRAY
+        );
+
+        if (!in_array($this->type, $types)) {
+            throw new Exception('Type does not exist');
+        }
     }
+
 }
diff --git a/core/Settings/Settings.php b/core/Settings/Settings.php
new file mode 100644
index 0000000000..6c076f8cac
--- /dev/null
+++ b/core/Settings/Settings.php
@@ -0,0 +1,107 @@
+<?php
+/**
+ * Piwik - free/libre analytics platform
+ *
+ * @link http://piwik.org
+ * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
+ *
+ */
+namespace Piwik\Settings;
+
+/**
+ * Base class of all settings providers.
+ *
+ * @api
+ */
+abstract class Settings
+{
+    /**
+     * An array containing all available settings: Array ( [setting-name] => [setting] )
+     *
+     * @var Setting[]
+     */
+    private $settings = array();
+
+    protected $pluginName;
+
+    public function __construct()
+    {
+        if (!isset($this->pluginName)) {
+            $classname = get_class($this);
+            $parts     = explode('\\', $classname);
+
+            if (count($parts) >= 3) {
+                $this->pluginName = $parts[2];
+            } else {
+                throw new \Exception(sprintf('Plugin Settings must have a plugin name specified in %s, could not detect plugin name', $classname));
+            }
+        }
+    }
+
+    /**
+     * @ignore
+     */
+    public function getPluginName()
+    {
+        return $this->pluginName;
+    }
+
+    /**
+     * @ignore
+     * @return Setting
+     */
+    public function getSetting($name)
+    {
+        if (array_key_exists($name, $this->settings)) {
+            return $this->settings[$name];
+        }
+    }
+
+    /**
+     * Implemented by descendants. This method should define plugin settings (via the
+     * {@link addSetting()}) method and set the introduction text (via the
+     * {@link setIntroduction()}).
+     */
+    abstract protected function init();
+
+    /**
+     * Returns the settings that can be displayed for the current user.
+     *
+     * @return Setting[]
+     */
+    public function getSettingsWritableByCurrentUser()
+    {
+        return array_filter($this->settings, function (Setting $setting) {
+            return $setting->isWritableByCurrentUser();
+        });
+    }
+
+    /**
+     * Makes a new plugin setting available.
+     *
+     * @param Setting $setting
+     * @throws \Exception       If there is a setting with the same name that already exists.
+     *                          If the name contains non-alphanumeric characters.
+     */
+    protected function addSetting(Setting $setting)
+    {
+        $name = $setting->getName();
+
+        if (isset($this->settings[$name])) {
+            throw new \Exception(sprintf('A setting with name "%s" does already exist for plugin "%s"', $name, $this->pluginName));
+        }
+
+        $this->settings[$name] = $setting;
+    }
+
+    /**
+     * Saves (persists) the current setting values in the database.
+     */
+    public function save()
+    {
+        foreach ($this->settings as $setting) {
+            $setting->save();
+        }
+    }
+
+}
diff --git a/core/Settings/Storage.php b/core/Settings/Storage.php
deleted file mode 100644
index 131c01b111..0000000000
--- a/core/Settings/Storage.php
+++ /dev/null
@@ -1,148 +0,0 @@
-<?php
-/**
- * Piwik - free/libre analytics platform
- *
- * @link http://piwik.org
- * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
- *
- */
-
-namespace Piwik\Settings;
-
-use Piwik\Option;
-
-/**
- * Base setting type class.
- *
- * @api
- */
-class Storage implements StorageInterface
-{
-
-    /**
-     * Array containing all plugin settings values: Array( [setting-key] => [setting-value] ).
-     *
-     * @var array
-     */
-    protected $settingsValues = array();
-
-    // for lazy loading of setting values
-    private $settingValuesLoaded = false;
-
-    private $pluginName;
-
-    public function __construct($pluginName)
-    {
-        $this->pluginName = $pluginName;
-    }
-
-    /**
-     * Saves (persists) the current setting values in the database.
-     */
-    public function save()
-    {
-        $this->loadSettingsIfNotDoneYet();
-
-        Option::set($this->getOptionKey(), serialize($this->settingsValues));
-    }
-
-    /**
-     * Removes all settings for this plugin from the database. Useful when uninstalling
-     * a plugin.
-     */
-    public function deleteAllValues()
-    {
-        $this->deleteSettingsFromStorage();
-
-        $this->settingsValues = array();
-        $this->settingValuesLoaded = false;
-    }
-
-    protected function deleteSettingsFromStorage()
-    {
-        Option::delete($this->getOptionKey());
-    }
-
-    /**
-     * Returns the current value for a setting. If no value is stored, the default value
-     * is be returned.
-     *
-     * @param Setting $setting
-     * @return mixed
-     * @throws \Exception If the setting does not exist or if the current user is not allowed to change the value
-     *                    of this setting.
-     */
-    public function getValue(Setting $setting)
-    {
-        $this->loadSettingsIfNotDoneYet();
-
-        if (array_key_exists($setting->getKey(), $this->settingsValues)) {
-            return $this->settingsValues[$setting->getKey()];
-        }
-
-        return $setting->defaultValue;
-    }
-
-    /**
-     * Sets (overwrites) the value of a setting in memory. To persist the change, {@link save()} must be
-     * called afterwards, otherwise the change has no effect.
-     *
-     * Before the setting is changed, the {@link Piwik\Settings\Setting::$validate} and
-     * {@link Piwik\Settings\Setting::$transform} closures will be invoked (if defined). If there is no validation
-     * filter, the setting value will be casted to the appropriate data type.
-     *
-     * @param Setting $setting
-     * @param string $value
-     * @throws \Exception If the setting does not exist or if the current user is not allowed to change the value
-     *                    of this setting.
-     */
-    public function setValue(Setting $setting, $value)
-    {
-        $this->loadSettingsIfNotDoneYet();
-
-        $this->settingsValues[$setting->getKey()] = $value;
-    }
-
-    /**
-     * Unsets a setting value in memory. To persist the change, {@link save()} must be
-     * called afterwards, otherwise the change has no effect.
-     *
-     * @param Setting $setting
-     */
-    public function deleteValue(Setting $setting)
-    {
-        $this->loadSettingsIfNotDoneYet();
-
-        $key = $setting->getKey();
-
-        if (array_key_exists($key, $this->settingsValues)) {
-            unset($this->settingsValues[$key]);
-        }
-    }
-
-    public function getOptionKey()
-    {
-        return 'Plugin_' . $this->pluginName . '_Settings';
-    }
-
-    private function loadSettingsIfNotDoneYet()
-    {
-        if ($this->settingValuesLoaded) {
-            return;
-        }
-
-        $this->settingValuesLoaded = true;
-        $this->settingsValues = $this->loadSettings();
-    }
-
-    protected function loadSettings()
-    {
-        $values = Option::get($this->getOptionKey());
-
-        if (!empty($values)) {
-            return unserialize($values);
-        }
-
-        return array();
-    }
-}
diff --git a/core/Settings/Storage/Backend/BackendInterface.php b/core/Settings/Storage/Backend/BackendInterface.php
new file mode 100644
index 0000000000..624493460e
--- /dev/null
+++ b/core/Settings/Storage/Backend/BackendInterface.php
@@ -0,0 +1,47 @@
+<?php
+/**
+ * Piwik - free/libre analytics platform
+ *
+ * @link http://piwik.org
+ * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
+ *
+ */
+namespace Piwik\Settings\Storage\Backend;
+
+/**
+ * Interface for a storage backend. Any new storage backend must implement this interface.
+ */
+interface BackendInterface
+{
+
+    /**
+     * Get an id that identifies the current storage. Eg `Plugin_$pluginName_Settings` could be a storage id
+     * for plugin settings. It's kind of like a cache key and the value will be actually used for this by a cache
+     * decorator.
+     *
+     * @return string
+     */
+    public function getStorageId();
+
+    /**
+     * Saves (persists) the current setting values in the database. Always all values that belong to a group of
+     * settings or backend needs to be passed. Usually existing values will be deleted and new values will be saved
+     * @param array $values An array of key value pairs where $settingName => $settingValue.
+     *                      Eg array('settingName1' > 'settingValue1')
+     */
+    public function save($values);
+
+    /**
+     * Deletes all saved settings.
+     * @return void
+     */
+    public function delete();
+
+    /**
+     * Loads previously saved setting values and returns them (if some were saved)
+     *
+     * @return array An array of key value pairs where $settingName => $settingValue.
+     *               Eg array('settingName1' > 'settingValue1')
+     */
+    public function load();
+}
diff --git a/core/Settings/Storage/Backend/Cache.php b/core/Settings/Storage/Backend/Cache.php
new file mode 100644
index 0000000000..f3150d77ee
--- /dev/null
+++ b/core/Settings/Storage/Backend/Cache.php
@@ -0,0 +1,78 @@
+<?php
+/**
+ * Piwik - free/libre analytics platform
+ *
+ * @link http://piwik.org
+ * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
+ *
+ */
+
+namespace Piwik\Settings\Storage\Backend;
+
+use Piwik\Settings\Storage;
+use Piwik\Tracker;
+use Piwik\Cache as PiwikCache;
+
+/**
+ * Loads settings from tracker cache instead of database. If not yet present in tracker cache will cache it.
+ *
+ * Can be used as a decorator in combination with any other storage backend.
+ */
+class Cache implements BackendInterface
+{
+    /**
+     * @var BackendInterface
+     */
+    private $backend;
+
+    public function __construct(BackendInterface $backend)
+    {
+        $this->backend = $backend;
+    }
+
+    /**
+     * Saves (persists) the current setting values in the database.
+     */
+    public function save($values)
+    {
+        $this->backend->save($values);
+        self::clearCache();
+    }
+
+    public function getStorageId()
+    {
+        return $this->backend->getStorageId();
+    }
+
+    public function delete()
+    {
+        $this->backend->delete();
+        self::clearCache();
+    }
+
+    public function load()
+    {
+        $cacheId = $this->getStorageId();
+        $cache = self::buildCache();
+
+        if ($cache->contains($cacheId)) {
+            return $cache->fetch($cacheId);
+        }
+
+        $settings = $this->backend->load();
+        $cache->save($cacheId, $settings);
+
+        return $settings;
+    }
+
+    public static function clearCache()
+    {
+        Tracker\Cache::deleteTrackerCache();
+        self::buildCache()->flushAll();
+    }
+
+    public static function buildCache()
+    {
+        return PiwikCache::getEagerCache();
+    }
+}
diff --git a/core/Settings/Storage/Backend/MeasurableSettingsTable.php b/core/Settings/Storage/Backend/MeasurableSettingsTable.php
new file mode 100644
index 0000000000..22452288c8
--- /dev/null
+++ b/core/Settings/Storage/Backend/MeasurableSettingsTable.php
@@ -0,0 +1,167 @@
+<?php
+/**
+ * Piwik - free/libre analytics platform
+ *
+ * @link http://piwik.org
+ * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
+ *
+ */
+
+namespace Piwik\Settings\Storage\Backend;
+
+use Piwik\Common;
+use Piwik\Db;
+use Exception;
+
+/**
+ * Measurable settings backend. Stores all settings in a "site_setting" database table.
+ *
+ * If a value that needs to be stored is an array, will insert a new row for each value of this array.
+ */
+class MeasurableSettingsTable implements BackendInterface
+{
+    /**
+     * @var int
+     */
+    private $idSite;
+
+    /**
+     * @var string
+     */
+    private $pluginName;
+
+    /**
+     * @var Db\AdapterInterface
+     */
+    private $db;
+
+    public function __construct($idSite, $pluginName)
+    {
+        if (empty($pluginName)) {
+            throw new Exception('No plugin name given for MeasurableSettingsTable backend');
+        }
+
+        if (empty($idSite)) {
+            throw new Exception('No idSite given for MeasurableSettingsTable backend');
+        }
+
+        $this->idSite = (int) $idSite;
+        $this->pluginName = $pluginName;
+    }
+
+    private function initDbIfNeeded()
+    {
+        if (!isset($this->db)) {
+            // we need to avoid db creation on instance creation, especially important in tracker mode
+            // the db might be never actually used when values are eg fetched from a cache
+            $this->db = Db::get();
+        }
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getStorageId()
+    {
+        return 'MeasurableSettings_' . $this->idSite . '_' . $this->pluginName;
+    }
+
+    /**
+     * Saves (persists) the current setting values in the database.
+     */
+    public function save($values)
+    {
+        $this->initDbIfNeeded();
+
+        $table = $this->getTableName();
+
+        $this->delete();
+
+        foreach ($values as $name => $value) {
+            if (!is_array($value)) {
+                $value = array($value);
+            }
+
+            foreach ($value as $val) {
+                if (!isset($val)) {
+                    continue;
+                }
+
+                if (is_bool($val)) {
+                    $val = (int) $val;
+                }
+
+                $sql  = "INSERT INTO $table (`idsite`, `plugin_name`, `setting_name`, `setting_value`) VALUES (?, ?, ?, ?)";
+                $bind = array($this->idSite, $this->pluginName, $name, $val);
+
+                $this->db->query($sql, $bind);
+            }
+        }
+    }
+
+    public function load()
+    {
+        $this->initDbIfNeeded();
+
+        $table = $this->getTableName();
+
+        $sql  = "SELECT `setting_name`, `setting_value` FROM " . $table . " WHERE idsite = ? and plugin_name = ?";
+        $bind = array($this->idSite, $this->pluginName);
+
+        $settings = $this->db->fetchAll($sql, $bind);
+
+        $flat = array();
+        foreach ($settings as $setting) {
+            $name = $setting['setting_name'];
+
+            if (array_key_exists($name, $flat)) {
+                if (!is_array($flat[$name])) {
+                    $flat[$name] = array($flat[$name]);
+                }
+                $flat[$name][] = $setting['setting_value'];
+            } else {
+                $flat[$name] = $setting['setting_value'];
+            }
+        }
+
+        return $flat;
+    }
+
+    private function getTableName()
+    {
+        return Common::prefixTable('site_setting');
+    }
+
+    public function delete()
+    {
+        $this->initDbIfNeeded();
+
+        $table = $this->getTableName();
+        $sql   = "DELETE FROM $table WHERE `idsite` = ? and plugin_name = ?";
+        $bind  = array($this->idSite, $this->pluginName);
+
+        $this->db->query($sql, $bind);
+    }
+
+    /**
+     * @internal
+     * @param int $idSite
+     * @throws \Exception
+     */
+    public static function removeAllSettingsForSite($idSite)
+    {
+        $query = sprintf('DELETE FROM %s WHERE idsite = ?', Common::prefixTable('site_setting'));
+        Db::query($query, array($idSite));
+    }
+
+    /**
+     * @internal
+     * @param string $pluginName
+     * @throws \Exception
+     */
+    public static function removeAllSettingsForPlugin($pluginName)
+    {
+        $query = sprintf('DELETE FROM %s WHERE plugin_name = ?', Common::prefixTable('site_setting'));
+        Db::query($query, array($pluginName));
+    }
+}
diff --git a/core/Settings/Storage/Backend/Null.php b/core/Settings/Storage/Backend/Null.php
new file mode 100644
index 0000000000..cc64c55654
--- /dev/null
+++ b/core/Settings/Storage/Backend/Null.php
@@ -0,0 +1,44 @@
+<?php
+/**
+ * Piwik - free/libre analytics platform
+ *
+ * @link http://piwik.org
+ * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
+ *
+ */
+
+namespace Piwik\Settings\Storage\Backend;
+
+use Piwik\Settings\Storage;
+
+/**
+ * Static / temporary storage where a value shall never be persisted. Meaning it will use the default value
+ * for each request until configured differently. Useful for tests etc.
+ */
+class Null implements BackendInterface
+{
+    private $storageId;
+
+    public function __construct($storageId)
+    {
+        $this->storageId = $storageId;
+    }
+
+    public function load()
+    {
+        return array();
+    }
+
+    public function getStorageId()
+    {
+        return $this->storageId;
+    }
+
+    public function delete()
+    {
+    }
+
+    public function save($values)
+    {
+    }
+}
diff --git a/core/Settings/Storage/Backend/PluginSettingsTable.php b/core/Settings/Storage/Backend/PluginSettingsTable.php
new file mode 100644
index 0000000000..87476ff8fb
--- /dev/null
+++ b/core/Settings/Storage/Backend/PluginSettingsTable.php
@@ -0,0 +1,175 @@
+<?php
+/**
+ * Piwik - free/libre analytics platform
+ *
+ * @link http://piwik.org
+ * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
+ *
+ */
+
+namespace Piwik\Settings\Storage\Backend;
+
+use Piwik\Common;
+use Piwik\Db;
+use Exception;
+
+/**
+ * Plugin settings backend. Stores all settings in a "plugin_setting" database table.
+ *
+ * If a value that needs to be stored is an array, will insert a new row for each value of this array.
+ */
+class PluginSettingsTable implements BackendInterface
+{
+    /**
+     * @var string
+     */
+    private $pluginName;
+
+    /**
+     * @var string
+     */
+    private $userLogin;
+
+    /**
+     * @var Db\AdapterInterface
+     */
+    private $db;
+
+    public function __construct($pluginName, $userLogin)
+    {
+        if (empty($pluginName)) {
+            throw new Exception('No plugin name given for PluginSettingsTable backend');
+        }
+
+        if ($userLogin === false || $userLogin === null) {
+            throw new Exception('Invalid user login name given for PluginSettingsTable backend');
+        }
+
+        $this->pluginName = $pluginName;
+        $this->userLogin = $userLogin;
+    }
+
+    private function initDbIfNeeded()
+    {
+        if (!isset($this->db)) {
+            // we do not want to create a db connection on backend creation
+            $this->db = Db::get();
+        }
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getStorageId()
+    {
+        return 'PluginSettings_' . $this->pluginName . '_User_' . $this->userLogin;
+    }
+
+    /**
+     * Saves (persists) the current setting values in the database.
+     */
+    public function save($values)
+    {
+        $this->initDbIfNeeded();
+
+        $table = $this->getTableName();
+
+        $this->delete();
+
+        foreach ($values as $name => $value) {
+
+            if (!is_array($value)) {
+                $value = array($value);
+            }
+
+            foreach ($value as $val) {
+                if (!isset($val)) {
+                    continue;
+                }
+
+                if (is_bool($val)) {
+                    $val = (int) $val;
+                }
+
+                $sql  = "INSERT INTO $table (`plugin_name`, `user_login`, `setting_name`, `setting_value`) VALUES (?, ?, ?, ?)";
+                $bind = array($this->pluginName, $this->userLogin, $name, $val);
+
+                $this->db->query($sql, $bind);
+            }
+        }
+    }
+
+    public function load()
+    {
+        $this->initDbIfNeeded();
+
+        $sql  = "SELECT `setting_name`, `setting_value` FROM " . $this->getTableName() . " WHERE plugin_name = ? and user_login = ?";
+        $bind = array($this->pluginName, $this->userLogin);
+
+        $settings = $this->db->fetchAll($sql, $bind);
+
+        $flat = array();
+        foreach ($settings as $setting) {
+            $name = $setting['setting_name'];
+
+            if (array_key_exists($name, $flat)) {
+                if (!is_array($flat[$name])) {
+                    $flat[$name] = array($flat[$name]);
+                }
+                $flat[$name][] = $setting['setting_value'];
+            } else {
+                $flat[$name] = $setting['setting_value'];
+            }
+        }
+
+        return $flat;
+    }
+
+    private function getTableName()
+    {
+        return Common::prefixTable('plugin_setting');
+    }
+
+    public function delete()
+    {
+        $this->initDbIfNeeded();
+
+        $table = $this->getTableName();
+        $sql   = "DELETE FROM $table WHERE `plugin_name` = ? and `user_login` = ?";
+        $bind  = array($this->pluginName, $this->userLogin);
+
+        $this->db->query($sql, $bind);
+    }
+
+    /**
+     * Unsets all settings for a user. The settings will be removed from the database. Used when
+     * a user is deleted.
+     *
+     * @internal
+     * @param string $userLogin
+     * @throws \Exception If the `$userLogin` is empty. Otherwise we would delete most plugin settings
+     */
+    public static function removeAllUserSettingsForUser($userLogin)
+    {
+        if (empty($userLogin)) {
+            throw new Exception('No userLogin specified. Cannot remove all settings for this user');
+        }
+
+        $table = Common::prefixTable('plugin_setting');
+        Db::get()->query(sprintf('DELETE FROM %s WHERE user_login = ?', $table), array($userLogin));
+    }
+
+    /**
+     * Unsets all settings for a plugin. The settings will be removed from the database. Used when
+     * a plugin is uninstalled.
+     *
+     * @internal
+     * @param string $pluginName
+     * @throws \Exception If the `$userLogin` is empty.
+     */
+    public static function removeAllSettingsForPlugin($pluginName)
+    {
+        $table = Common::prefixTable('plugin_setting');
+        Db::get()->query(sprintf('DELETE FROM %s WHERE plugin_name = ?', $table), array($pluginName));
+    }
+}
diff --git a/core/Settings/Storage/Backend/SitesTable.php b/core/Settings/Storage/Backend/SitesTable.php
new file mode 100644
index 0000000000..81de89b100
--- /dev/null
+++ b/core/Settings/Storage/Backend/SitesTable.php
@@ -0,0 +1,122 @@
+<?php
+/**
+ * Piwik - free/libre analytics platform
+ *
+ * @link http://piwik.org
+ * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
+ *
+ */
+
+namespace Piwik\Settings\Storage\Backend;
+
+use Piwik\Plugins\SitesManager\Model;
+use Piwik\Site;
+use Exception;
+
+/**
+ * Backend for an existing site. Stores all settings in the "site" database table.
+ */
+class SitesTable implements BackendInterface
+{
+    /**
+     * @var int
+     */
+    private $idSite;
+
+    private $commaSeparatedArrayFields = array(
+        'sitesearch_keyword_parameters',
+        'sitesearch_category_parameters',
+        'excluded_user_agents',
+        'excluded_parameters',
+        'excluded_ips'
+    );
+
+    // these fields are standard fields of a site and cannot be adjusted via a setting
+    private $allowedNames = array(
+        'ecommerce', 'sitesearch', 'sitesearch_keyword_parameters',
+        'sitesearch_category_parameters', 'exclude_unknown_urls',
+        'excluded_ips', 'excluded_parameters',
+        'excluded_user_agents', 'keep_url_fragment', 'urls'
+    );
+
+    public function __construct($idSite)
+    {
+        if (empty($idSite)) {
+            throw new Exception('No idSite given for Measurable backend');
+        }
+
+        $this->idSite = (int) $idSite;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getStorageId()
+    {
+        return 'SitesTable_' . $this->idSite;
+    }
+
+    /**
+     * Saves (persists) the current setting values in the database.
+     */
+    public function save($values)
+    {
+        $model = $this->getModel();
+
+        foreach ($values as $key => $value) {
+            if (!in_array($key, $this->allowedNames)) {
+                unset($values[$key]);
+                continue;
+            }
+
+            if (is_array($value) && in_array($key, $this->commaSeparatedArrayFields)) {
+                $values[$key] = implode(',', $value);
+            } elseif (is_bool($value)) {
+                $values[$key] = (int) $value;
+            }
+        }
+
+        if (!empty($values['urls'])) {
+            $urls = array_unique($values['urls']);
+            $values['main_url'] = array_shift($urls);
+
+            $model->deleteSiteAliasUrls($this->idSite);
+            foreach ($urls as $url) {
+                $model->insertSiteUrl($this->idSite, $url);
+            }
+        }
+
+        unset($values['urls']);
+
+        $model->updateSite($values, $this->idSite);
+        Site::clearCacheForSite($this->idSite);
+    }
+
+    public function load()
+    {
+        if (!empty($this->idSite)) {
+            $site = Site::getSite($this->idSite);
+
+            $urls = $this->getModel();
+            $site['urls'] = $urls->getSiteUrlsFromId($this->idSite);
+
+            foreach ($this->commaSeparatedArrayFields as $field) {
+                if (!empty($site[$field]) && is_string($site[$field])) {
+                    $site[$field] = explode(',', $site[$field]);
+                }
+            }
+
+            return $site;
+        }
+    }
+
+    private function getModel()
+    {
+        return new Model();
+    }
+
+    public function delete()
+    {
+    }
+
+}
diff --git a/core/Settings/Storage/Factory.php b/core/Settings/Storage/Factory.php
index 87d54ad3b1..5c1c6ca645 100644
--- a/core/Settings/Storage/Factory.php
+++ b/core/Settings/Storage/Factory.php
@@ -9,20 +9,113 @@
 
 namespace Piwik\Settings\Storage;
 
-use Piwik\Settings\Storage;
+use Piwik\Settings\Storage\Backend\BackendInterface;
 use Piwik\SettingsServer;
-use Piwik\Tracker\SettingsStorage;
 
+/**
+ * Factory to create an instance of a storage. The storage can be created with different backends depending on the need.
+ *
+ * @package Piwik\Settings\Storage
+ */
 class Factory
 {
-    public static function make($pluginName)
+    // cache prevents multiple loading of storage
+    private $cache = array();
+
+    /**
+     * Get a storage instance for plugin settings.
+     *
+     * The storage will hold values that belong to the given plugin name and user login. Be aware that instances
+     * for a specific plugin and login will be cached during one request for better performance.
+     *
+     * @param string $pluginName
+     * @param string $userLogin Use an empty string if settings should be not for a specific login
+     * @return Storage
+     */
+    public function getPluginStorage($pluginName, $userLogin)
+    {
+        $id = $pluginName . '#' . $userLogin;
+
+        if (!isset($this->cache[$id])) {
+            $backend = new Backend\PluginSettingsTable($pluginName, $userLogin);
+            $this->cache[$id] = $this->makeStorage($backend);
+        }
+
+        return $this->cache[$id];
+    }
+
+    /**
+     * Get a storage instance for measurable settings.
+     *
+     * The storage will hold values that belong to the given idSite and plugin name. Be aware that a storage instance
+     * for a specific site and plugin will be cached during one request for better performance.
+     *
+     * @param int $idSite   If idSite is empty it will use a backend that never actually persists any value. Pass
+     *                      $idSite = 0 to create a storage for a site that is about to be created.
+     * @param string $pluginName
+     * @return Storage
+     */
+    public function getMeasurableSettingsStorage($idSite, $pluginName)
+    {
+        $id = 'measurableSettings' . (int) $idSite . '#' . $pluginName;
+
+        if (empty($idSite)) {
+            return $this->getNonPersistentStorage($id . '#nonpersistent');
+        }
+
+        if (!isset($this->cache[$id])) {
+            $backend = new Backend\MeasurableSettingsTable($idSite, $pluginName);
+            $this->cache[$id] = $this->makeStorage($backend);
+        }
+
+        return $this->cache[$id];
+    }
+
+    /**
+     * Get a storage instance for settings that will be saved in the "site" table.
+     *
+     * The storage will hold values that belong to the given idSite. Be aware that a storage instance for a specific
+     * site will be cached during one request for better performance.
+     *
+     * @param int $idSite   If idSite is empty it will use a backend that never actually persists any value. Pass
+     *                      $idSite = 0 to create a storage for a site that is about to be created.
+     *
+     * @param int $idSite
+     * @return Storage
+     */
+    public function getSitesTable($idSite)
+    {
+        $id = 'sitesTable#' . $idSite;
+
+        if (empty($idSite)) {
+            return $this->getNonPersistentStorage($id . '#nonpersistent');
+        }
+
+        if (!isset($this->cache[$id])) {
+            $backend = new Backend\SitesTable($idSite);
+            $this->cache[$id] = $this->makeStorage($backend);
+        }
+
+        return $this->cache[$id];
+    }
+
+    /**
+     * Get a storage with a backend that will never persist or load any value.
+     *
+     * @param string $key
+     * @return Storage
+     */
+    public function getNonPersistentStorage($key)
+    {
+        return new Storage(new Backend\Null($key));
+    }
+
+    private function makeStorage(BackendInterface $backend)
     {
         if (SettingsServer::isTrackerApiRequest()) {
-            $storage = new SettingsStorage($pluginName);
-        } else {
-            $storage = new Storage($pluginName);
+            $backend = new Backend\Cache($backend);
         }
 
-        return $storage;
+        return new Storage($backend);
     }
 }
diff --git a/core/Settings/Storage/StaticStorage.php b/core/Settings/Storage/StaticStorage.php
deleted file mode 100644
index d8a43b6c9a..0000000000
--- a/core/Settings/Storage/StaticStorage.php
+++ /dev/null
@@ -1,34 +0,0 @@
-<?php
-/**
- * Piwik - free/libre analytics platform
- *
- * @link http://piwik.org
- * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
- *
- */
-
-namespace Piwik\Settings\Storage;
-
-use Piwik\Settings\Storage;
-
-/**
- * Static / temporary storage where a value will never be persisted meaning it will use the default value
- * for each request until configured differently. Useful for tests.
- *
- * @api
- */
-class StaticStorage extends Storage
-{
-
-    protected function loadSettings()
-    {
-        return array();
-    }
-
-    /**
-     * Saves (persists) the current setting values in the database.
-     */
-    public function save()
-    {
-    }
-}
diff --git a/core/Settings/Storage/Storage.php b/core/Settings/Storage/Storage.php
new file mode 100644
index 0000000000..b24282068d
--- /dev/null
+++ b/core/Settings/Storage/Storage.php
@@ -0,0 +1,117 @@
+<?php
+/**
+ * Piwik - free/libre analytics platform
+ *
+ * @link http://piwik.org
+ * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
+ *
+ */
+
+namespace Piwik\Settings\Storage;
+
+use Piwik\Settings\Storage\Backend;
+
+/**
+ * A storage stores values for multiple settings. Storing multiple settings here saves having to do
+ * a "get" for each individual setting. A storage is usually stared between all individual setting instances
+ * within a plugin.
+ */
+class Storage
+{
+    /**
+     * Array containing all plugin settings values: Array( [setting-key] => [setting-value] ).
+     *
+     * @var array
+     */
+    protected $settingsValues = array();
+
+    // for lazy loading of setting values
+    private $settingValuesLoaded = false;
+
+    /**
+     * @var Backend\BackendInterface
+     */
+    private $backend;
+
+    /**
+     * Defines whether a value has changed since the settings were loaded or not.
+     * @var bool
+     */
+    private $isDirty = false;
+
+    public function __construct(Backend\BackendInterface $backend)
+    {
+        $this->backend = $backend;
+    }
+
+    /**
+     * Get the currently used backend for this storage.
+     * @return Backend\BackendInterface
+     */
+    public function getBackend()
+    {
+        return $this->backend;
+    }
+
+    /**
+     * Saves (persists) the current setting values in the database if a value has actually changed.
+     */
+    public function save()
+    {
+        if ($this->isDirty) {
+            $this->backend->save($this->settingsValues);
+
+            $this->isDirty = false;
+
+            Backend\Cache::clearCache();
+        }
+    }
+
+    /**
+     * Returns the current value for a setting. If no value is stored, the default value
+     * is be returned.
+     *
+     * @param string $key  The name / key of a setting
+     * @param mixed $defaultValue Default value that will be used in case no value for this setting exists yet
+     * @param string $type The PHP internal type the value of the setting should have, see FieldConfig::TYPE_*
+     *                     constants. Only an actual value of the setting will be converted to the given type, the
+     *                     default value will not be converted.
+     * @return mixed
+     */
+    public function getValue($key, $defaultValue, $type)
+    {
+        $this->loadSettingsIfNotDoneYet();
+
+        if (array_key_exists($key, $this->settingsValues)) {
+            settype($this->settingsValues[$key], $type);
+            return $this->settingsValues[$key];
+        }
+
+        return $defaultValue;
+    }
+
+    /**
+     * Sets (overwrites) the value of a setting in memory. To persist the change across requests, {@link save()} must be
+     * called.
+     *
+     * @param string $key  The name / key of a setting
+     * @param mixed $value The value that shall be set for the given setting.
+     */
+    public function setValue($key, $value)
+    {
+        $this->loadSettingsIfNotDoneYet();
+
+        $this->isDirty = true;
+        $this->settingsValues[$key] = $value;
+    }
+
+    private function loadSettingsIfNotDoneYet()
+    {
+        if ($this->settingValuesLoaded) {
+            return;
+        }
+
+        $this->settingValuesLoaded = true;
+        $this->settingsValues = $this->backend->load();
+    }
+}
diff --git a/core/Settings/StorageInterface.php b/core/Settings/StorageInterface.php
deleted file mode 100644
index 6a4a76c5ac..0000000000
--- a/core/Settings/StorageInterface.php
+++ /dev/null
@@ -1,59 +0,0 @@
-<?php
-/**
- * Piwik - free/libre analytics platform
- *
- * @link http://piwik.org
- * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
- *
- */
-namespace Piwik\Settings;
-
-/**
- * Base type of all Setting storage implementations.
- */
-interface StorageInterface
-{
-    /**
-     * Gets the current value for this setting. If no value is specified, the default value will be returned.
-     *
-     * @param Setting $setting
-     *
-     * @return mixed
-     *
-     * @throws \Exception In case the setting does not exist or if the current user is not allowed to change the value
-     *                    of this setting.
-     */
-    public function getValue(Setting $setting);
-
-    /**
-     * Removes the value for the given setting. Make sure to call `save()` afterwards, otherwise the removal has no
-     * effect.
-     *
-     * @param Setting $setting
-     */
-    public function deleteValue(Setting $setting);
-
-    /**
-     * Sets (overwrites) the value for the given setting. Make sure to call `save()` afterwards, otherwise the change
-     * has no effect. Before the value is saved a possibly define `validate` closure and `filter` closure will be
-     * called. Alternatively the value will be casted to the specfied setting type.
-     *
-     * @param Setting $setting
-     * @param string $value
-     *
-     * @throws \Exception In case the setting does not exist or if the current user is not allowed to change the value
-     *                    of this setting.
-     */
-    public function setValue(Setting $setting, $value);
-
-    /**
-     * Removes all settings for this plugin from the database. Useful when uninstalling
-     * a plugin.
-     */
-    public function deleteAllValues();
-
-    /**
-     * Saves (persists) the current setting values in the database.
-     */
-    public function save();
-}
diff --git a/core/Settings/UserSetting.php b/core/Settings/UserSetting.php
deleted file mode 100644
index aa3a08c400..0000000000
--- a/core/Settings/UserSetting.php
+++ /dev/null
@@ -1,146 +0,0 @@
-<?php
-/**
- * Piwik - free/libre analytics platform
- *
- * @link http://piwik.org
- * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
- *
- */
-
-namespace Piwik\Settings;
-
-use Piwik\Common;
-use Piwik\Piwik;
-
-/**
- * Describes a per user setting. Each user will be able to change this setting for themselves,
- * but not for other users.
- *
- *
- * @api
- */
-class UserSetting extends Setting
-{
-    private $userLogin = null;
-
-    /**
-     * Null while not initialized, bool otherwise.
-     * @var null|bool
-     */
-    private $hasReadAndWritePermission = null;
-
-    /**
-     * Constructor.
-     *
-     * @param string $name The setting's persisted name.
-     * @param string $title The setting's display name.
-     * @param null|string $userLogin The user this setting applies to. Will default to the current user login.
-     */
-    public function __construct($name, $title, $userLogin = null)
-    {
-        parent::__construct($name, $title);
-
-        $this->setUserLogin($userLogin);
-    }
-
-    /**
-     * Returns `true` if this setting can be displayed for the current user, `false` if otherwise.
-     *
-     * @return bool
-     */
-    public function isReadableByCurrentUser()
-    {
-        return $this->isWritableByCurrentUser();
-    }
-
-    /**
-     * Returns `true` if this setting can be displayed for the current user, `false` if otherwise.
-     *
-     * @return bool
-     */
-    public function isWritableByCurrentUser()
-    {
-        if (isset($this->hasReadAndWritePermission)) {
-            return $this->hasReadAndWritePermission;
-        }
-
-        $this->hasReadAndWritePermission = Piwik::isUserHasSomeViewAccess();
-
-        return $this->hasReadAndWritePermission;
-    }
-
-    /**
-     * Returns the display order. User settings are displayed after system settings.
-     *
-     * @return int
-     */
-    public function getOrder()
-    {
-        return 60;
-    }
-
-    private function buildUserSettingName($name, $userLogin = null)
-    {
-        if (empty($userLogin)) {
-            $userLogin = Piwik::getCurrentUserLogin();
-        }
-
-        // the asterisk tag is indeed important here and better than an underscore. Imagine a plugin has the settings
-        // "api_password" and "api". A user having the login "_password" could otherwise under circumstances change the
-        // setting for "api" although he is not allowed to. It is not so important at the moment because only alNum is
-        // currently allowed as a name this might change in the future.
-        $appendix = '#' . $userLogin . '#';
-
-        if (Common::stringEndsWith($name, $appendix)) {
-            return $name;
-        }
-
-        return $name . $appendix;
-    }
-
-    /**
-     * Sets the name of the user this setting will be set for.
-     *
-     * @param $userLogin
-     * @throws \Exception If the current user does not have permission to set the setting value
-     *                    of `$userLogin`.
-     */
-    public function setUserLogin($userLogin)
-    {
-        if (!empty($userLogin) && !Piwik::hasUserSuperUserAccessOrIsTheUser($userLogin)) {
-            throw new \Exception('You do not have the permission to read the settings of a different user');
-        }
-
-        $this->userLogin = $userLogin;
-        $this->key       = $this->buildUserSettingName($this->name, $userLogin);
-    }
-
-    /**
-     * Unsets all settings for a user. The settings will be removed from the database. Used when
-     * a user is deleted.
-     *
-     * @param string $userLogin
-     * @throws \Exception If the `$userLogin` is empty.
-     */
-    public static function removeAllUserSettingsForUser($userLogin)
-    {
-        if (empty($userLogin)) {
-            throw new \Exception('No userLogin specified');
-        }
-
-        $pluginsSettings = Manager::getAllPluginSettings();
-
-        foreach ($pluginsSettings as $pluginSettings) {
-            $settings = $pluginSettings->getSettings();
-
-            foreach ($settings as $setting) {
-                if ($setting instanceof UserSetting) {
-                    $setting->setUserLogin($userLogin);
-                    $setting->removeValue();
-                }
-            }
-
-            $pluginSettings->save();
-        }
-    }
-}
diff --git a/core/Site.php b/core/Site.php
index 3bc535fc2d..a45a4a5e2e 100644
--- a/core/Site.php
+++ b/core/Site.php
@@ -419,6 +419,17 @@ class Site
     }
 
     /**
+     * Clears the site data cache.
+     *
+     * See also {@link setSites()} and {@link setSitesFromArray()}.
+     */
+    public static function clearCacheForSite($idSite)
+    {
+        $idSite = (int)$idSite;
+        unset(self::$infoSites[$idSite]);
+    }
+
+    /**
      * Utility function. Returns the value of the specified field for the
      * site with the specified ID.
      *
diff --git a/core/Tracker/SettingsStorage.php b/core/Tracker/SettingsStorage.php
deleted file mode 100644
index a69e03553f..0000000000
--- a/core/Tracker/SettingsStorage.php
+++ /dev/null
@@ -1,58 +0,0 @@
-<?php
-/**
- * Piwik - free/libre analytics platform
- *
- * @link http://piwik.org
- * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
- *
- */
-
-namespace Piwik\Tracker;
-
-use Piwik\Settings\Storage;
-use Piwik\Tracker;
-use Piwik\Cache as PiwikCache;
-
-/**
- * Loads settings from tracker cache instead of database. If not yet present in tracker cache will cache it.
- */
-class SettingsStorage extends Storage
-{
-    protected function loadSettings()
-    {
-        $cacheId = $this->getOptionKey();
-        $cache = $this->getCache();
-
-        if ($cache->contains($cacheId)) {
-            $settings = $cache->fetch($cacheId);
-        } else {
-            $settings = parent::loadSettings();
-
-            $cache->save($cacheId, $settings);
-        }
-
-        return $settings;
-    }
-
-    public function save()
-    {
-        parent::save();
-        self::clearCache();
-    }
-
-    private function getCache()
-    {
-        return self::buildCache($this->getOptionKey());
-    }
-
-    public static function clearCache()
-    {
-        Cache::deleteTrackerCache();
-        self::buildCache()->flushAll();
-    }
-
-    private static function buildCache()
-    {
-        return PiwikCache::getEagerCache();
-    }
-}
diff --git a/core/Updates/3.0.0-b1.php b/core/Updates/3.0.0-b1.php
index 301bc44a1b..b7fbd2d027 100644
--- a/core/Updates/3.0.0-b1.php
+++ b/core/Updates/3.0.0-b1.php
@@ -11,6 +11,7 @@ namespace Piwik\Updates;
 
 use Piwik\Common;
 use Piwik\Db;
+use Piwik\DbHelper;
 use Piwik\Updater;
 use Piwik\Updates;
 use Piwik\Plugins\Dashboard;
@@ -30,7 +31,11 @@ class Updates_3_0_0_b1 extends Updates
         $allGoals = $db->fetchAll(sprintf("SELECT DISTINCT idgoal FROM %s", Common::prefixTable('goal')));
         $allDashboards = $db->fetchAll(sprintf("SELECT * FROM %s", Common::prefixTable('user_dashboard')));
 
-        return $this->getDashboardMigrationSqls($allDashboards, $allGoals);
+        $queries = $this->getDashboardMigrationSqls($allDashboards, $allGoals);
+        $queries = $this->getPluginSettingsMigrationQueries($queries, $db);
+        $queries = $this->getSiteSettingsMigrationQueries($queries);
+
+        return $queries;
     }
 
     public function doUpdate(Updater $updater)
@@ -38,11 +43,104 @@ class Updates_3_0_0_b1 extends Updates
         $updater->executeMigrationQueries(__FILE__, $this->getMigrationQueries($updater));
     }
 
+    /**
+     * @param $queries
+     * @param Db $db
+     * @return mixed
+     */
+    private function getPluginSettingsMigrationQueries($queries, $db)
+    {
+        $pluginSettingsTableName = $this->getPluginSettingsTableName();
+        $dbSettings = new Db\Settings();
+        $engine = $dbSettings->getEngine();
+
+        $pluginSettingsTable = "CREATE TABLE $pluginSettingsTableName (
+                          `plugin_name` VARCHAR(60) NOT NULL,
+                          `setting_name` VARCHAR(255) NOT NULL,
+                          `setting_value` LONGTEXT NOT NULL,
+                          `user_login` VARCHAR(100) NOT NULL DEFAULT '',
+                              INDEX(plugin_name, user_login)
+                            ) ENGINE=$engine DEFAULT CHARSET=utf8
+            ";
+        $queries[$pluginSettingsTable] = 1050;
+
+        $optionTable = Common::prefixTable('option');
+        $query = 'SELECT `option_name`, `option_value` FROM `' . $optionTable . '` WHERE `option_name` LIKE "Plugin_%_Settings"';
+        $options = Db::get()->fetchAll($query);
+
+        foreach ($options as $option) {
+            $name = $option['option_name'];
+            $pluginName = str_replace(array('Plugin_', '_Settings'), '', $name);
+            $values = @unserialize($option['option_value']);
+
+            if (empty($values)) {
+                continue;
+            }
+
+            foreach ($values as $settingName => $settingValue) {
+                if (!is_array($settingValue)) {
+                    $settingValue = array($settingValue);
+                }
+
+                foreach ($settingValue as $val) {
+                    $queries[$this->createPluginSettingQuery($pluginName, $settingName, $val)] = 1062;
+                }
+            }
+        }
+
+        $queries[$query = sprintf('DELETE FROM `%s` WHERE `option_name` like "Plugin_%%_Settings"', $optionTable)] = false;
+
+        return $queries;
+    }
+
+    /**
+     * @param $queries
+     * @param Db $db
+     * @return mixed
+     */
+    private function getSiteSettingsMigrationQueries($queries)
+    {
+        $table = Common::prefixTable('site_setting');
+
+        $pluginSettingsTable = "ALTER TABLE $table ADD COLUMN `plugin_name` VARCHAR(60) NOT NULL AFTER `idsite`";
+        $queries[$pluginSettingsTable] = 1060;
+        $queries["ALTER TABLE $table DROP PRIMARY KEY, ADD INDEX(idsite, plugin_name);"] = false;
+
+        // we cannot migrate existing settings as we do not know the related plugin name, but this feature
+        // (measurablesettings) was not really used anyway. If a migration is somewhere really needed it has to be
+        // handled in the plugin
+        $queries[sprintf('DELETE FROM `%s`', $table)] = false;
+
+        return $queries;
+    }
+
+    private function createPluginSettingQuery($pluginName, $settingName, $settingValue)
+    {
+        $table = $this->getPluginSettingsTableName();
+
+        $login = '';
+        if (preg_match('/^.+#(.+)#$/', $settingName, $matches)) {
+            $login = $matches[1];
+            $settingName = str_replace('#' . $login . '#', '', $settingName);
+        }
+
+        $db = Db::get();
+
+        $query  = sprintf("INSERT INTO %s (plugin_name, setting_name, setting_value, user_login) VALUES ", $table);
+        $query .= sprintf("(%s, %s, %s, %s)", $db->quote($pluginName), $db->quote($settingName), $db->quote($settingValue), $db->quote($login));
+
+        return $query;
+    }
+
+    private function getPluginSettingsTableName()
+    {
+        return Common::prefixTable('plugin_setting');
+    }
+
     private function getDashboardMigrationSqls($allDashboards, $allGoals)
     {
         $sqls = array();
 
-
         // update dashboard to use new widgets
         $oldWidgets = array(
             array (
diff --git a/core/ViewDataTable/Config.php b/core/ViewDataTable/Config.php
index f275aebe58..14a6e13ed5 100644
--- a/core/ViewDataTable/Config.php
+++ b/core/ViewDataTable/Config.php
@@ -15,7 +15,7 @@ use Piwik\DataTable;
 use Piwik\DataTable\Filter\PivotByDimension;
 use Piwik\Metrics;
 use Piwik\Plugins\API\API;
-use Piwik\Plugin\Reports;
+use Piwik\Plugin\ReportsProvider;
 
 /**
  * Contains base display properties for {@link Piwik\Plugin\ViewDataTable}s. Manipulating these
@@ -717,7 +717,7 @@ class Config
 
     private function setShouldShowPivotBySubtable()
     {
-        $report = Reports::factory($this->controllerName, $this->controllerAction);
+        $report = ReportsProvider::factory($this->controllerName, $this->controllerAction);
 
         if (empty($report)) {
             $this->show_pivot_by_subtable = false;
diff --git a/core/ViewDataTable/Factory.php b/core/ViewDataTable/Factory.php
index 543f1280cf..846de225c2 100644
--- a/core/ViewDataTable/Factory.php
+++ b/core/ViewDataTable/Factory.php
@@ -12,7 +12,7 @@ use Piwik\Common;
 use Piwik\Piwik;
 use Piwik\Plugin\Report;
 use Piwik\Plugins\CoreVisualizations\Visualizations\HtmlTable;
-use Piwik\Plugin\Reports;
+use Piwik\Plugin\ReportsProvider;
 
 /**
  * Provides a means of creating {@link Piwik\Plugin\ViewDataTable} instances by ID.
@@ -168,7 +168,7 @@ class Factory
     private static function getReport($apiAction)
     {
         list($module, $action) = explode('.', $apiAction);
-        $report = Reports::factory($module, $action);
+        $report = ReportsProvider::factory($module, $action);
         return $report;
     }
 
diff --git a/core/Widget/WidgetsList.php b/core/Widget/WidgetsList.php
index dfeb004277..14c626b0a9 100644
--- a/core/Widget/WidgetsList.php
+++ b/core/Widget/WidgetsList.php
@@ -175,7 +175,7 @@ class WidgetsList
     {
         $list = new static;
 
-        $widgets = StaticContainer::get('Piwik\Plugin\Widgets');
+        $widgets = StaticContainer::get('Piwik\Plugin\WidgetsProvider');
 
         $widgetContainerConfigs = $widgets->getWidgetContainerConfigs();
         foreach ($widgetContainerConfigs as $config) {
@@ -191,7 +191,7 @@ class WidgetsList
             }
         }
 
-        $reports = StaticContainer::get('Piwik\Plugin\Reports');
+        $reports = StaticContainer::get('Piwik\Plugin\ReportsProvider');
         $reports = $reports->getAllReports();
         foreach ($reports as $report) {
             if ($report->isEnabled()) {