Added basic Theme support.

Theme is set at application level (in Admin -> Settings).
For now, themes can override stylesheets only (application.css).

git-svn-id: http://redmine.rubyforge.org/svn/trunk@818 e93f8b46-1217-0410-a6f0-8f06a7374b81

lib/redmine.rb

@@ -1,6 +1,7 @@
 require 'redmine/access_control'
 require 'redmine/menu_manager'
 require 'redmine/mime_type'
+require 'redmine/themes'
 require 'redmine/plugin'
 
 begin

lib/redmine/themes.rb

@@ -0,0 +1,72 @@
+# redMine - project management software
+# Copyright (C) 2006-2007  Jean-Philippe Lang
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+# 
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+
+module Redmine
+  module Themes
+  
+    # Return an array of installed themes
+    def self.themes
+      @@installed_themes ||= scan_themes
+    end
+    
+    # Rescan themes directory
+    def self.rescan
+      @@installed_themes = scan_themes
+    end
+    
+    # Return theme for given id, or nil if it's not found
+    def self.theme(id)
+      themes.find {|t| t.id == id}
+    end
+  
+    # Class used to represent a theme
+    class Theme
+      attr_reader :name, :dir, :stylesheets
+      
+      def initialize(path)
+        @dir = File.basename(path)
+        @name = @dir.humanize
+        @stylesheets = Dir.glob("#{path}/stylesheets/*.css").collect {|f| File.basename(f).gsub(/\.css$/, '')}
+      end
+      
+      # Directory name used as the theme id
+      def id; dir end
+
+      def <=>(theme)
+        name <=> theme.name
+      end
+    end
+    
+    private
+        
+    def self.scan_themes
+      dirs = Dir.glob('public/themes/*').select do |f|
+        # A theme should at least override application.css
+        File.directory?(f) && File.exist?("#{f}/stylesheets/application.css")
+      end
+      dirs.collect {|dir| Theme.new(dir)}.sort
+    end
+  end
+end
+
+module ApplicationHelper
+  def stylesheet_path(source)
+    @current_theme ||= Redmine::Themes.theme(Setting.ui_theme)
+    super((@current_theme && @current_theme.stylesheets.include?(source)) ?
+      "/themes/#{@current_theme.dir}/stylesheets/#{source}" : source)
+  end
+end