module TrustyCms
  class TaskSupport
    class << self
      def establish_connection
        unless ActiveRecord::Base.connected?
          connection_hash = YAML.load_file("#{Rails.root}/config/database.yml").to_hash
          env_connection = connection_hash[Rails.env]
          ActiveRecord::Base.establish_connection(env_connection)
        end
      end

      def config_export(path = "#{Rails.root}/config/trusty_config.yml")
        establish_connection
        FileUtils.mkdir_p(File.dirname(path))
        if File.open(File.expand_path(path), 'w') { |f| YAML.dump(TrustyCms::Config.to_hash.to_yaml, f) }
          puts "TrustyCms::Config saved to #{path}"
        end
      end

      def config_import(path = "#{Rails.root}/config/trusty_config.yml", clear = nil)
        establish_connection
        if File.exist?(path)
          begin
            TrustyCms::Config.transaction do
              TrustyCms::Config.delete_all if clear
              configs = YAML.load(YAML.load_file(path))
              configs.each do |key, value|
                c = TrustyCms::Config.find_or_initialize_by_key(key)
                c.value = value
                c.save
              end
            end
            puts "TrustyCms::Config updated from #{path}"
          rescue ActiveRecord::RecordInvalid => e
            puts "IMPORT FAILED and rolled back. #{e}"
          end
        else
          puts "No file exists at #{path}"
        end
      end

      # Write the combined content of files in dir into cache_file in the same dir.
      #
      def cache_files(dir, files, cache_file)
        cache_content = files.collect do |f|
          File.read(File.join(dir, f))
        end.join("\n\n")

        cache_path = File.join(dir, cache_file)
        File.delete(cache_path) if File.exist?(cache_path)
        File.open(cache_path, 'w+') { |f| f.write(cache_content) }
      end

      # Reads through the layout file and returns an array of JS filenames
      #
      def find_admin_js
        layout = "#{TRUSTY_CMS_ROOT}/app/views/layouts/application"
        js_regexp = /javascript_include_tag %w\((.*)\), :cache => 'admin\/all/
        files = File.open(layout) { |f| f.read.match(js_regexp)[1].split }
        files.collect { |f| f.split('/').last + '.js' }
      end

      def cache_admin_js
        dir = "#{Rails.root}/public/javascripts/admin"
        cache_files(dir, find_admin_js, 'all.js')
      end
    end
  end
end