1 files changed, 57 insertions, 0 deletions
diff --git a/core/Columns/ComputedMetricFactory.php b/core/Columns/ComputedMetricFactory.php
new file mode 100644
index 0000000000..0b2b2f5426
--- /dev/null
+++ b/core/Columns/ComputedMetricFactory.php
@@ -0,0 +1,57 @@
+<?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\Columns;
+
+use Piwik\Piwik;
+use Piwik\Plugin\ArchivedMetric;
+use Piwik\Plugin\ComputedMetric;
+use Piwik\Plugin\Report;
+
+/**
+ * A factory to create computed metrics.
+ *
+ * @api since Piwik 3.2.0
+ */
+class ComputedMetricFactory
+{
+    /**
+     * @var MetricsList
+     */
+    private $metricsList = null;
+
+    /**
+     * Generates a new report metric factory.
+     * @param MetricsList $list A report list instance
+     * @ignore
+     */
+    public function __construct(MetricsList $list)
+    {
+        $this->metricsList = $list;
+    }
+
+    /**
+     * @return \Piwik\Plugin\ComputedMetric
+     */
+    public function createComputedMetric($metricName1, $metricName2, $aggregation)
+    {
+        $metric1 = $this->metricsList->getMetric($metricName1);
+
+        if (!$metric1 instanceof ArchivedMetric || !$metric1->getDimension()) {
+            throw new \Exception('Only possible to create computed metric for an archived metric with a dimension');
+        }
+
+        $dimension1 = $metric1->getDimension();
+
+        $metric = new ComputedMetric($metricName1, $metricName2, $aggregation);
+        $metric->setCategory($dimension1->getCategoryId());
+
+        return $metric;
+    }
+
+}
+\ No newline at end of file