Add Gitlab::Themes module; remove Gitlab::Theme

Now we can simply loop through all themes, among other things.

This also removes the `dark_theme` / `light_theme` classes and the
`theme_type` helper, since they weren't used anywhere.

2 files changed, 67 insertions, 50 deletions

diff --git a/lib/gitlab/theme.rb b/lib/gitlab/theme.rb
deleted file mode 100644
index e5a1f1b44d9..00000000000
--- a/lib/gitlab/theme.rb
+++ /dev/null
@@ -1,50 +0,0 @@
-module Gitlab
-  class Theme
-    BASIC  = 1 unless const_defined?(:BASIC)
-    MARS   = 2 unless const_defined?(:MARS)
-    MODERN = 3 unless const_defined?(:MODERN)
-    GRAY   = 4 unless const_defined?(:GRAY)
-    COLOR  = 5 unless const_defined?(:COLOR)
-    BLUE   = 6 unless const_defined?(:BLUE)
-
-    def self.classes
-      @classes ||= {
-        BASIC  => 'ui_basic',
-        MARS   => 'ui_mars',
-        MODERN => 'ui_modern',
-        GRAY   => 'ui_gray',
-        COLOR  => 'ui_color',
-        BLUE   => 'ui_blue'
-      }
-    end
-
-    def self.css_class_by_id(id)
-      id ||= Gitlab.config.gitlab.default_theme
-      classes[id]
-    end
-
-    def self.types
-      @types ||= {
-        BASIC  => 'light_theme',
-        MARS   => 'dark_theme',
-        MODERN => 'dark_theme',
-        GRAY   => 'dark_theme',
-        COLOR  => 'dark_theme',
-        BLUE   => 'light_theme'
-      }
-    end
-
-    def self.type_css_class_by_id(id)
-      id ||= Gitlab.config.gitlab.default_theme
-      types[id]
-    end
-
-    # Convenience method to get a space-separated String of all the theme
-    # classes that might be applied to the `body` element
-    #
-    # Returns a String
-    def self.body_classes
-      (classes.values + types.values).uniq.join(' ')
-    end
-  end
-end
diff --git a/lib/gitlab/themes.rb b/lib/gitlab/themes.rb
new file mode 100644
index 00000000000..5209df92795
--- /dev/null
+++ b/lib/gitlab/themes.rb
@@ -0,0 +1,67 @@
+module Gitlab
+  # Module containing GitLab's application theme definitions and helper methods
+  # for accessing them.
+  module Themes
+    # Theme ID used when no `default_theme` configuration setting is provided.
+    APPLICATION_DEFAULT = 2
+
+    # Struct class representing a single Theme
+    Theme = Struct.new(:id, :name, :css_class)
+
+    # All available Themes
+    THEMES = [
+      Theme.new(1, 'Graphite', 'ui_graphite'),
+      Theme.new(2, 'Charcoal', 'ui_charcoal'),
+      Theme.new(3, 'Green',    'ui_green'),
+      Theme.new(4, 'Gray',     'ui_gray'),
+      Theme.new(5, 'Violet',   'ui_violet'),
+      Theme.new(6, 'Blue',     'ui_blue')
+    ].freeze
+
+    # Convenience method to get a space-separated String of all the theme
+    # classes that might be applied to the `body` element
+    #
+    # Returns a String
+    def self.body_classes
+      THEMES.collect(&:css_class).uniq.join(' ')
+    end
+
+    # Get a Theme by its ID
+    #
+    # If the ID is invalid, returns the default Theme.
+    #
+    # id - Integer ID
+    #
+    # Returns a Theme
+    def self.by_id(id)
+      THEMES.detect { |t| t.id == id } || default
+    end
+
+    # Get the default Theme
+    #
+    # Returns a Theme
+    def self.default
+      by_id(default_id)
+    end
+
+    # Iterate through each Theme
+    #
+    # Yields the Theme object
+    def self.each(&block)
+      THEMES.each(&block)
+    end
+
+    private
+
+    def self.default_id
+      id = Gitlab.config.gitlab.default_theme.to_i
+
+      # Prevent an invalid configuration setting from causing an infinite loop
+      if id < THEMES.first.id || id > THEMES.last.id
+        APPLICATION_DEFAULT
+      else
+        id
+      end
+    end
+  end
+end