1 files changed, 103 insertions, 0 deletions
diff --git a/core/misc/collapse.js b/core/misc/collapse.js
new file mode 100644
index 00000000000..1a98dc0e04c
--- /dev/null
+++ b/core/misc/collapse.js
@@ -0,0 +1,103 @@
+(function ($) {
+
+/**
+ * Toggle the visibility of a fieldset using smooth animations.
+ */
+Drupal.toggleFieldset = function (fieldset) {
+  var $fieldset = $(fieldset);
+  if ($fieldset.is('.collapsed')) {
+    var $content = $('> .fieldset-wrapper', fieldset).hide();
+    $fieldset
+      .removeClass('collapsed')
+      .trigger({ type: 'collapsed', value: false })
+      .find('> legend span.fieldset-legend-prefix').html(Drupal.t('Hide'));
+    $content.slideDown({
+      duration: 'fast',
+      easing: 'linear',
+      complete: function () {
+        Drupal.collapseScrollIntoView(fieldset);
+        fieldset.animating = false;
+      },
+      step: function () {
+        // Scroll the fieldset into view.
+        Drupal.collapseScrollIntoView(fieldset);
+      }
+    });
+  }
+  else {
+    $fieldset.trigger({ type: 'collapsed', value: true });
+    $('> .fieldset-wrapper', fieldset).slideUp('fast', function () {
+      $fieldset
+        .addClass('collapsed')
+        .find('> legend span.fieldset-legend-prefix').html(Drupal.t('Show'));
+      fieldset.animating = false;
+    });
+  }
+};
+
+/**
+ * Scroll a given fieldset into view as much as possible.
+ */
+Drupal.collapseScrollIntoView = function (node) {
+  var h = document.documentElement.clientHeight || document.body.clientHeight || 0;
+  var offset = document.documentElement.scrollTop || document.body.scrollTop || 0;
+  var posY = $(node).offset().top;
+  var fudge = 55;
+  if (posY + node.offsetHeight + fudge > h + offset) {
+    if (node.offsetHeight > h) {
+      window.scrollTo(0, posY);
+    }
+    else {
+      window.scrollTo(0, posY + node.offsetHeight - h + fudge);
+    }
+  }
+};
+
+Drupal.behaviors.collapse = {
+  attach: function (context, settings) {
+    $('fieldset.collapsible', context).once('collapse', function () {
+      var $fieldset = $(this);
+      // Expand fieldset if there are errors inside, or if it contains an
+      // element that is targeted by the uri fragment identifier. 
+      var anchor = location.hash && location.hash != '#' ? ', ' + location.hash : '';
+      if ($('.error' + anchor, $fieldset).length) {
+        $fieldset.removeClass('collapsed');
+      }
+
+      var summary = $('<span class="summary"></span>');
+      $fieldset.
+        bind('summaryUpdated', function () {
+          var text = $.trim($fieldset.drupalGetSummary());
+          summary.html(text ? ' (' + text + ')' : '');
+        })
+        .trigger('summaryUpdated');
+
+      // Turn the legend into a clickable link, but retain span.fieldset-legend
+      // for CSS positioning.
+      var $legend = $('> legend .fieldset-legend', this);
+
+      $('<span class="fieldset-legend-prefix element-invisible"></span>')
+        .append($fieldset.hasClass('collapsed') ? Drupal.t('Show') : Drupal.t('Hide'))
+        .prependTo($legend)
+        .after(' ');
+
+      // .wrapInner() does not retain bound events.
+      var $link = $('<a class="fieldset-title" href="#"></a>')
+        .prepend($legend.contents())
+        .appendTo($legend)
+        .click(function () {
+          var fieldset = $fieldset.get(0);
+          // Don't animate multiple times.
+          if (!fieldset.animating) {
+            fieldset.animating = true;
+            Drupal.toggleFieldset(fieldset);
+          }
+          return false;
+        });
+
+      $legend.append(summary);
+    });
+  }
+};
+
+})(jQuery);