/**
 * @file
 * Extends the Drupal AJAX functionality to integrate the dialog API.
 */

(function ($, Drupal) {

  'use strict';

  /**
   * Initialize dialogs for Ajax purposes.
   *
   * @type {Drupal~behavior}
   *
   * @prop {Drupal~behaviorAttach} attach
   *   Attaches the behaviors for dialog ajax functionality.
   */
  Drupal.behaviors.dialog = {
    attach: function (context, settings) {
      var $context = $(context);

      // Provide a known 'drupal-modal' DOM element for Drupal-based modal
      // dialogs. Non-modal dialogs are responsible for creating their own
      // elements, since there can be multiple non-modal dialogs at a time.
      if (!$('#drupal-modal').length) {
        // Add 'ui-front' jQuery UI class so jQuery UI widgets like autocomplete
        // sit on top of dialogs. For more information see
        // http://api.jqueryui.com/theming/stacking-elements/.
        $('<div id="drupal-modal" class="ui-front"/>').hide().appendTo('body');
      }

      // Special behaviors specific when attaching content within a dialog.
      // These behaviors usually fire after a validation error inside a dialog.
      var $dialog = $context.closest('.ui-dialog-content');
      if ($dialog.length) {
        // Remove and replace the dialog buttons with those from the new form.
        if ($dialog.dialog('option', 'drupalAutoButtons')) {
          // Trigger an event to detect/sync changes to buttons.
          $dialog.trigger('dialogButtonsChange');
        }

        // Force focus on the modal when the behavior is run.
        $dialog.dialog('widget').trigger('focus');
      }

      var originalClose = settings.dialog.close;
      // Overwrite the close method to remove the dialog on closing.
      settings.dialog.close = function (event) {
        originalClose.apply(settings.dialog, arguments);
        $(event.target).remove();
      };
    },

    /**
     * Scan a dialog for any primary buttons and move them to the button area.
     *
     * @param {jQuery} $dialog
     *   An jQuery object containing the element that is the dialog target.
     *
     * @return {Array}
     *   An array of buttons that need to be added to the button area.
     */
    prepareDialogButtons: function ($dialog) {
      var buttons = [];
      var $buttons = $dialog.find('.form-actions input[type=submit], .form-actions a.button');
      $buttons.each(function () {
        // Hidden form buttons need special attention. For browser consistency,
        // the button needs to be "visible" in order to have the enter key fire
        // the form submit event. So instead of a simple "hide" or
        // "display: none", we set its dimensions to zero.
        // See http://mattsnider.com/how-forms-submit-when-pressing-enter/
        var $originalButton = $(this).css({
          display: 'block',
          width: 0,
          height: 0,
          padding: 0,
          border: 0,
          overflow: 'hidden'
        });
        buttons.push({
          text: $originalButton.html() || $originalButton.attr('value'),
          class: $originalButton.attr('class'),
          click: function (e) {
            // If the original button is an anchor tag, triggering the "click"
            // event will not simulate a click. Use the click method instead.
            if ($originalButton.is('a')) {
              $originalButton[0].click();
            }
            else {
              $originalButton.trigger('mousedown').trigger('mouseup').trigger('click');
              e.preventDefault();
            }
          }
        });
      });
      return buttons;
    }
  };

  /**
   * Command to open a dialog.
   *
   * @param {Drupal.Ajax} ajax
   *   The Drupal Ajax object.
   * @param {object} response
   *   Object holding the server response.
   * @param {number} [status]
   *   The HTTP status code.
   *
   * @return {bool|undefined}
   *   Returns false if there was no selector property in the response object.
   */
  Drupal.AjaxCommands.prototype.openDialog = function (ajax, response, status) {
    if (!response.selector) {
      return false;
    }
    var $dialog = $(response.selector);
    if (!$dialog.length) {
      // Create the element if needed.
      $dialog = $('<div id="' + response.selector.replace(/^#/, '') + '" class="ui-front"/>').appendTo('body');
    }
    // Set up the wrapper, if there isn't one.
    if (!ajax.wrapper) {
      ajax.wrapper = $dialog.attr('id');
    }

    // Use the ajax.js insert command to populate the dialog contents.
    response.command = 'insert';
    response.method = 'html';
    ajax.commands.insert(ajax, response, status);

    // Move the buttons to the jQuery UI dialog buttons area.
    if (!response.dialogOptions.buttons) {
      response.dialogOptions.drupalAutoButtons = true;
      response.dialogOptions.buttons = Drupal.behaviors.dialog.prepareDialogButtons($dialog);
    }

    // Bind dialogButtonsChange.
    $dialog.on('dialogButtonsChange', function () {
      var buttons = Drupal.behaviors.dialog.prepareDialogButtons($dialog);
      $dialog.dialog('option', 'buttons', buttons);
    });

    // Open the dialog itself.
    response.dialogOptions = response.dialogOptions || {};
    var dialog = Drupal.dialog($dialog.get(0), response.dialogOptions);
    if (response.dialogOptions.modal) {
      dialog.showModal();
    }
    else {
      dialog.show();
    }

    // Add the standard Drupal class for buttons for style consistency.
    $dialog.parent().find('.ui-dialog-buttonset').addClass('form-actions');
  };

  /**
   * Command to close a dialog.
   *
   * If no selector is given, it defaults to trying to close the modal.
   *
   * @param {Drupal.Ajax} [ajax]
   *   The ajax object.
   * @param {object} response
   *   Object holding the server response.
   * @param {string} response.selector
   *   The selector of the dialog.
   * @param {bool} response.persist
   *   Whether to persist the dialog element or not.
   * @param {number} [status]
   *   The HTTP status code.
   */
  Drupal.AjaxCommands.prototype.closeDialog = function (ajax, response, status) {
    var $dialog = $(response.selector);
    if ($dialog.length) {
      Drupal.dialog($dialog.get(0)).close();
      if (!response.persist) {
        $dialog.remove();
      }
    }

    // Unbind dialogButtonsChange.
    $dialog.off('dialogButtonsChange');
  };

  /**
   * Command to set a dialog property.
   *
   * JQuery UI specific way of setting dialog options.
   *
   * @param {Drupal.Ajax} [ajax]
   *   The Drupal Ajax object.
   * @param {object} response
   *   Object holding the server response.
   * @param {string} response.selector
   *   Selector for the dialog element.
   * @param {string} response.optionsName
   *   Name of a key to set.
   * @param {string} response.optionValue
   *   Value to set.
   * @param {number} [status]
   *   The HTTP status code.
   */
  Drupal.AjaxCommands.prototype.setDialogOption = function (ajax, response, status) {
    var $dialog = $(response.selector);
    if ($dialog.length) {
      $dialog.dialog('option', response.optionName, response.optionValue);
    }
  };

  /**
   * Binds a listener on dialog creation to handle the cancel link.
   *
   * @param {jQuery.Event} e
   *   The event triggered.
   * @param {Drupal.dialog~dialogDefinition} dialog
   *   The dialog instance.
   * @param {jQuery} $element
   *   The jQuery collection of the dialog element.
   * @param {object} [settings]
   *   Dialog settings.
   */
  $(window).on('dialog:aftercreate', function (e, dialog, $element, settings) {
    $element.on('click.dialog', '.dialog-cancel', function (e) {
      dialog.close('cancel');
      e.preventDefault();
      e.stopPropagation();
    });
  });

  /**
   * Removes all 'dialog' listeners.
   *
   * @param {jQuery.Event} e
   *   The event triggered.
   * @param {Drupal.dialog~dialogDefinition} dialog
   *   The dialog instance.
   * @param {jQuery} $element
   *   jQuery collection of the dialog element.
   */
  $(window).on('dialog:beforeclose', function (e, dialog, $element) {
    $element.off('.dialog');
  });

})(jQuery, Drupal);
