require 'active_support/core_ext/hash/keys'

module TinyMCE::Rails
  module Helper
    # Initializes TinyMCE on the current page based on the global configuration.
    #
    # Custom options can be set via the options hash, which will be passed to
    # the TinyMCE init function.
    #
    # By default, all textareas with a class of "tinymce" will have the TinyMCE
    # editor applied. The current locale will also be used as the language when
    # TinyMCE language files are available, falling back to English if not
    # available. The :editor_selector and :language options can be used to
    # override these defaults.
    #
    # @example
    #   <%= tinymce(:theme => "advanced", :editor_selector => "editorClass") %>
    def tinymce(config=:default, options={})
      javascript_tag { tinymce_javascript(config, options) }
    end

    # Returns the JavaScript code required to initialize TinyMCE.
    def tinymce_javascript(config=:default, options={})
      <<-JAVASCRIPT.strip_heredoc.html_safe
      (function() {
        function initTinyMCE() {
          if (typeof tinyMCE != 'undefined') {
            tinyMCE.init(#{tinymce_configuration(config, options).to_javascript.gsub(/^/, ' ' * 12).sub(/\A\s+/, "")});
          } else {
            setTimeout(initTinyMCE, 50);
          }
        }

        initTinyMCE();
      })();
      JAVASCRIPT
    end

    # Returns the TinyMCE configuration object.
    # It should be converted to JavaScript (via #to_javascript) for use within JavaScript.
    def tinymce_configuration(config=:default, options={})
      options, config = config, :default if config.is_a?(Hash)
      options.stringify_keys!

      base_configuration = TinyMCE::Rails.configuration

      if base_configuration.is_a?(MultipleConfiguration)
        base_configuration = base_configuration.fetch(config)
      end

      base_configuration.merge(options)
    end

    # Includes TinyMCE javascript assets via a script tag.
    def tinymce_assets
      javascript_include_tag "tinymce"
    end

    # Allow methods to be called as module functions:
    #  e.g. TinyMCE::Rails.tinymce_javascript
    module_function :tinymce, :tinymce_javascript, :tinymce_configuration
    public :tinymce, :tinymce_javascript, :tinymce_configuration
  end
end