(function($) {

Drupal.plupload = Drupal.plupload || {};

/**
 * Attaches the Plupload behavior to each Plupload form element.
 */
Drupal.behaviors.plupload = {
  attach: function (context, settings) {
    $(".plupload-element", context).once('plupload-init', function () {
      var $this = $(this);

      // Merge the default settings and the element settings to get a full
      // settings object to pass to the Plupload library for this element.
      var id = $this.attr('id');
      var defaultSettings = settings.plupload['_default'] ? settings.plupload['_default'] : {};
      var elementSettings = (id && settings.plupload[id]) ? settings.plupload[id] : {};
      var pluploadSettings = $.extend({}, defaultSettings, elementSettings);

      // Do additional requirements testing to prevent a less than ideal runtime
      // from being used. For example, the Plupload library treats Firefox 3.5
      // as supporting HTML 5, but this is incorrect, because Firefox 3.5
      // doesn't support the 'multiple' attribute for file input controls. So,
      // if settings.plupload._requirements.html5.mozilla = '1.9.2', then we
      // remove 'html5' from pluploadSettings.runtimes if $.browser.mozilla is
      // true and if $.browser.version is less than '1.9.2'.
      if (settings.plupload['_requirements'] && pluploadSettings.runtimes) {
        var runtimes = pluploadSettings.runtimes.split(',');
        var filteredRuntimes = [];
        for (var i = 0; i < runtimes.length; i++) {
          var includeRuntime = true;
          if (settings.plupload['_requirements'][runtimes[i]]) {
            var requirements = settings.plupload['_requirements'][runtimes[i]];
            for (var browser in requirements) {
              if ($.browser[browser] && Drupal.plupload.compareVersions($.browser.version, requirements[browser]) < 0) {
                includeRuntime = false;
              }
            }
          }
          if (includeRuntime) {
            filteredRuntimes.push(runtimes[i]);
          }
        }
        pluploadSettings.runtimes = filteredRuntimes.join(',');
      }

      // Initialize Plupload for this element.
      $this.pluploadQueue(pluploadSettings);

    });
  }
};

 /**
  * Attaches the Plupload behavior to each Plupload form element.
  */
Drupal.behaviors.pluploadform = {
  attach: function(context, settings) {
    $('form', context).once('plupload-form', function() {
      if (0 < $(this).find('.plupload-element').length) {
        var $form = $(this);
        var originalFormAttributes = {
            'method': $form.attr('method'),
            'enctype': $form.attr('enctype'),
            'action': $form.attr('action'),
            'target': $form.attr('target')
        };      
  
        $(this).submit(function(e) {
          var completedPluploaders = 0;
          var totalPluploaders = $(this).find('.plupload-element').length;
          var errors = '';
  
          $(this).find('.plupload-element').each( function(index){
            var uploader = $(this).pluploadQueue();
  
            var id = $(this).attr('id');
            var defaultSettings = settings.plupload['_default'] ? settings.plupload['_default'] : {};
            var elementSettings = (id && settings.plupload[id]) ? settings.plupload[id] : {};
            var pluploadSettings = $.extend({}, defaultSettings, elementSettings);
  
            //Only allow the submit to proceed if there are files and they've all
            //completed uploading.
            //TODO: Implement a setting for whether the field is required, rather
            //than assuming that all are.
            if (uploader.state == plupload.STARTED) {
              errors += Drupal.t("Please wait while your files are being uploaded.");              
            }
            else if (uploader.files.length == 0 && !pluploadSettings.required) {
              completedPluploaders++;
            }       
  
            else if (uploader.files.length == 0) { 
              errors += Drupal.t("@index: You must upload at least one file.\n",{'@index': (index + 1)});
            }       
  
            else if (uploader.files.length > 0 && uploader.total.uploaded == uploader.files.length) {
              completedPluploaders++;
            }       
  
            else {  
              var stateChangedHandler = function() {
                if (uploader.total.uploaded == uploader.files.length) {
                  uploader.unbind('StateChanged', stateChangedHandler);
                  completedPluploaders++;
                  if (completedPluploaders == totalPluploaders ) {
                    //Plupload's html4 runtime has a bug where it changes the
                    //attributes of the form to handle the file upload, but then
                    //fails to change them back after the upload is finished.
                    for (var attr in originalFormAttributes) {
                      $form.attr(attr, originalFormAttributes[attr]);
                    }
                    $form.submit();
                    return true;
                  }
                }
              };
              uploader.bind('StateChanged', stateChangedHandler);
              uploader.start();
            }

          });
          if (completedPluploaders == totalPluploaders) {
            //Plupload's html4 runtime has a bug where it changes the
            //attributes of the form to handle the file upload, but then
            //fails to change them back after the upload is finished.
            for (var attr in originalFormAttributes) {
              $form.attr(attr, originalFormAttributes[attr]);
            }
            return true;
          }
          else if (0 < errors.length){
            alert(errors);
          }
         
          return false;
        });
      }
    });
  }
};


/**
 * Helper function to compare version strings.
 *
 * Returns one of:
 *   - A negative integer if a < b.
 *   - A positive integer if a > b.
 *   - 0 if a == b.
 */
Drupal.plupload.compareVersions = function (a, b) {
  a = a.split('.');
  b = b.split('.');
  // Return the most significant difference, if there is one.
  for (var i=0; i < Math.min(a.length, b.length); i++) {
    var compare = parseInt(a[i]) - parseInt(b[i]);
    if (compare != 0) {
      return compare;
    }
  }
  // If the common parts of the two version strings are equal, the greater
  // version number is the one with the most sections.
  return a.length - b.length;
}

})(jQuery);