From d9bd472beebd965aae9e9f5382bbeb4df41f122f Mon Sep 17 00:00:00 2001
From: Andrew Robert Nicols <andrew.nicols@luns.net.uk>
Date: Mon, 21 May 2012 11:49:26 +0100
Subject: [PATCH] MDL-33135 Prevent duplicate form submission on the course
 activity chooser

---
 lib/yui/chooserdialogue/chooserdialogue.js | 55 ++++++++++++++++++++--
 1 file changed, 51 insertions(+), 4 deletions(-)

diff --git a/lib/yui/chooserdialogue/chooserdialogue.js b/lib/yui/chooserdialogue/chooserdialogue.js
index 1cbb0fe4073..71c77a30a24 100644
--- a/lib/yui/chooserdialogue/chooserdialogue.js
+++ b/lib/yui/chooserdialogue/chooserdialogue.js
@@ -14,6 +14,9 @@ YUI.add('moodle-core-chooserdialogue', function(Y) {
         // The chooserdialogue container
         container : null,
 
+        // Any event listeners we may need to cancel later
+        listenevents : [],
+
         setup_chooser_dialogue : function(bodycontent, headercontent, config) {
             // Set Default options
             var params = {
@@ -45,6 +48,7 @@ YUI.add('moodle-core-chooserdialogue', function(Y) {
             this.container = this.overlay.get('boundingBox').one('#choosercontainer');
             this.options = this.container.all('.option input[type=radio]');
         },
+
         /**
          * Display the module chooser
          *
@@ -58,15 +62,33 @@ YUI.add('moodle-core-chooserdialogue', function(Y) {
             var bb = this.overlay.get('boundingBox');
             var dialogue = this.container.one('.alloptions');
 
+            var thisevent;
+
             // These will trigger a check_options call to display the correct help
-            this.container.on('click', this.check_options, this);
-            this.container.on('key_up', this.check_options, this);
-            this.container.on('dblclick', function(e) {
+            thisevent = this.container.on('click', this.check_options, this);
+            this.listenevents.push(thisevent);
+            thisevent = this.container.on('key_up', this.check_options, this);
+            this.listenevents.push(thisevent);
+            thisevent = this.container.on('dblclick', function(e) {
                 if (e.target.ancestor('div.option')) {
                     this.check_options();
+
+                    // Prevent duplicate submissions
+                    this.submitbutton.setAttribute('disabled', 'disabled');
+                    this.options.setAttribute('disabled', 'disabled');
+                    this.cancel_listenevents();
+
                     this.container.one('form').submit();
                 }
             }, this);
+            this.listenevents.push(thisevent);
+
+            this.container.one('form').on('submit', function(e) {
+                // Prevent duplicate submissions on submit
+                this.submitbutton.setAttribute('disabled', 'disabled');
+                this.options.setAttribute('disabled', 'disabled');
+                this.cancel_listenevents();
+            }, this);
 
             // Hook onto the cancel button to hide the form
             this.container.one('#addcancel').on('click', this.cancel_popup, this);
@@ -81,6 +103,9 @@ YUI.add('moodle-core-chooserdialogue', function(Y) {
             // Disable the submit element until the user makes a selection
             this.submitbutton.set('disabled', 'true');
 
+            // Ensure that the options are shown
+            this.options.removeAttribute('disabled');
+
             // Display the overlay
             this.overlay.show();
 
@@ -93,11 +118,28 @@ YUI.add('moodle-core-chooserdialogue', function(Y) {
             // Trigger check_options to set the initial jumpurl
             this.check_options();
         },
+
+        /**
+         * Cancel any listen events in the listenevents queue
+         *
+         * Several locations add event handlers which should only be called before the form is submitted. This provides
+         * a way of cancelling those events.
+         *
+         * @return void
+         */
+        cancel_listenevents : function () {
+            // Detach all listen events to prevent duplicate triggers
+            var thisevent;
+            while (thisevent = this.listenevents.shift()) {
+                thisevent.detach();
+            }
+        },
+
         /**
          * Calculate the optimum height of the chooser dialogue
          *
          * This tries to set a sensible maximum and minimum to ensure that some options are always shown, and preferably
-         * all, whilst fitting the box within the current viewport
+         * all, whilst fitting the box within the current viewport.
          *
          * @param dialogue Y.Node The dialogue
          * @return void
@@ -142,22 +184,26 @@ YUI.add('moodle-core-chooserdialogue', function(Y) {
             // out what we're setting at present -- shoud be the boudingBox
             bb.setStyle('top', dialoguetop + 'px');
         },
+
         handle_key_press : function(e) {
             if (e.keyCode == 27) {
                 this.cancel_popup(e);
             }
         },
+
         cancel_popup : function (e) {
             // Prevent normal form submission before hiding
             e.preventDefault();
             this.hide();
         },
+
         hide : function() {
             // Detach the global keypress handler before hiding
             Y.one('document').detach('keyup', this.handle_key_press, this);
             this.container.detachAll();
             this.overlay.hide();
         },
+
         check_options : function(e) {
             // Check which options are set, and change the parent class
             // to show/hide help as required
@@ -179,6 +225,7 @@ YUI.add('moodle-core-chooserdialogue', function(Y) {
                 }
             }, this);
         },
+
         option_selected : function(e) {
         }
     },