// $Id$

/**
 * Manipulation of content remove buttons.
 *
 * TableDrag objects for multiple value fields (and multigroups) are scanned
 * to find 'remove' checkboxes. These checkboxes are hidden when javascript is
 * enabled (using the Global CSS Killswitch, html.js, defined in drupal.js).
 * A new 'remove' button is created here in place of these checkboxes aimed to
 * provide a more user-friendly method to remove items.
 */
Drupal.behaviors.contentRemoveButtons = function(context) {
  $('table.content-multiple-table', context).not('.content-multiple-remove-buttons-processed').addClass('content-multiple-remove-buttons-processed').each(function() {
    var table = this, tableDrag = Drupal.tableDrag[$(table).attr('id')];

    // Replace 'remove' checkboxes with buttons.
    $('input.content-multiple-remove-checkbox', table).each(function() {
      var $checkbox = $(this), $row = $checkbox.parents('tr:first');
      var isRemoved = $checkbox.attr('checked');
      var $button = $(Drupal.theme('contentRemoveButton', tableDrag.getRemoveButtonTitle(isRemoved)));

      // Bind the onClick event to the 'remove' button.
      $button.bind('click', function(event) {
        Drupal.contentOnClickRemoveButton($button, $checkbox, tableDrag);
        return false;
      });

      // Attach the new button to the DOM tree.
      $checkbox.parent().append($button);

      // Wrap the contents of all cells (except the drag'n'drop, weight and
      // remove button cells) with a dummy block element. This operation makes
      // animations faster because we just need to show/hide a single element
      // per cell, and it also prevents from creating more than one warning
      // element per row.
      $row.children('td:not(.content-multiple-drag):not(.delta-order):not(.content-multiple-remove-cell)').each(function() {
        $(this).wrapInner('<div class="content-multiple-removed-wrapper"/>');
      });

      // If the row is removed, then hide the contents of the cells and show
      // the removed warning on the cell next to the drag'n'drop cell.
      if (isRemoved) {
        $('.content-multiple-removed-wrapper', $row).hide();
        $('.content-multiple-drag', $row).next(':first').append(Drupal.theme('contentRemovedWarning', tableDrag.getRemovedWarning()));

        // If the form has been submitted and any error was found, FAPI will
        // send back the same exact form that was submitted to show the error
        // messages, but it will not invoke the rendering engine which is where
        // we actually assign the removed class to the row, so we need to check
        // this situation here and add the class if it is not present.
        if (!$row.hasClass('content-multiple-removed-row')) {
          $row.addClass('content-multiple-removed-row');
        }
      }
    });
  });
};

/**
 * onClick handler for 'remove' buttons.
 */
Drupal.contentOnClickRemoveButton = function($button, $checkbox, tableDrag) {
  // Switch the state of the checkbox related to the 'remove' button.
  var isRemoved = !$checkbox.attr('checked');
  $checkbox.attr('checked', isRemoved);

  $button.parents('tr:first').each(function() {
    var row = this;

    // Switch the row class.
    if (isRemoved) {
      $(row).addClass('content-multiple-removed-row');
    }
    else {
      $(row).removeClass('content-multiple-removed-row');
    }

    // Switch the visibility state of the cell elements.
    $('.content-multiple-removed-wrapper', row).each(function() {
      var $cellWrapper = $(this);
      // Remove the warning during restore operation.
      if (!isRemoved && $('.content-multiple-removed-warning', row).size()) {
        $('.content-multiple-removed-warning', row).remove();
      }
      // Perform an animation to hide or show the contents of the cells.
      $cellWrapper.animate({opacity: (isRemoved ? 'hide' : 'show')}, 'slow', function() {
        // Show the removed warning during remove operation (only on the first cell).
        if (isRemoved && $cellWrapper.parent().prev(':first').hasClass('content-multiple-drag')) {
          $('.content-multiple-drag', row).next(':first').append(Drupal.theme('contentRemovedWarning', tableDrag.getRemovedWarning()));
        }
      });
    });

    // Display the table changed warning.
    tableDrag.displayChangedWarning();
  });

  // Switch the 'remove' button title.
  $button.attr('title', tableDrag.getRemoveButtonTitle(isRemoved));
};

/**
 * tableDrag extension; Display table change warning when appropriate.
 */
Drupal.tableDrag.prototype.displayChangedWarning = function() {
  if (this.changed == false) {
    $(Drupal.theme('tableDragChangedWarning')).insertAfter(this.table).hide().fadeIn('slow');
    this.changed = true;
  }
};

/**
 * Get the title of the 'remove' button.
 *
 * This method is an extension of the tableDrag object. This means a separate
 * module can override this method for a particular tableDrag object. For example,
 * the multigroup module can change the text to read 'Remove this group of items',
 * another module could change it to 'Remove this image', and so on...
 * To override this function:
 * <code>
 *  var tableId = $(table).attr('id');
 *  Drupal.tableDrag[tableId].getRemoveButtonTitle = function(isRemoved) {
 *    return (isRemoved ? Drupal.t('Restore this foo') : Drupal.t('Remove this foo'));
 *  };
 * </code>
 *
 * @param isRemoved
 *   A flag that indicates the state of the button.
 */
Drupal.tableDrag.prototype.getRemoveButtonTitle = function(isRemoved) {
  return (isRemoved ? Drupal.t('Restore this item') : Drupal.t('Remove this item'));
};

/**
 * Get the item removed warning.
 *
 * This method is an extension of the tableDrag object. It can be overridden by
 * a separate module. See getRemoveButtonTitle() for further information.
 */
Drupal.tableDrag.prototype.getRemovedWarning = function() {
  return Drupal.t('Removed');
};

/**
 * Theme the 'remove' button.
 */
Drupal.theme.prototype.contentRemoveButton = function(title) {
  return '<a href="javascript:void(0)" class="content-multiple-remove-button" title="'+ title +'"></a>';
};

/**
 * Theme the item removed warning.
 */
Drupal.theme.prototype.contentRemovedWarning = function(warning) {
  return '<div class="content-multiple-removed-warning">'+ warning +'</div>';
};