Merge in canvas refactorizations

[fnpeditor.git] / src / smartxml / smartxml.js

diff --git a/src/smartxml/smartxml.js b/src/smartxml/smartxml.js
index 426dce0..35c5299 100644 (file)
--- a/src/smartxml/smartxml.js
+++ b/src/smartxml/smartxml.js
@@ -560,6 +560,7 @@ $.extend(Document.prototype, Backbone.Events, {
         if(this._currentTransaction) {
             throw new Error('Nested transactions not supported!');
         }
+        this._rollbackBackup = this.root.clone();
         this._currentTransaction = new Transaction([], metadata);
     },
 
@@ -573,10 +574,28 @@ $.extend(Document.prototype, Backbone.Events, {
         this._currentTransaction = null;
     },
 
-    transaction: function(callback, context, metadata) {
+    rollbackTransaction: function() {
+        if(!this._currentTransaction) {
+            throw new Error('Transaction rollback requested, but there is no transaction in progress!');
+        }
+        this.replaceRoot(this._rollbackBackup);
+        this._rollbackBackup = null;
+        this._currentTransaction = null;
+    },
+
+    transaction: function(callback, params) {
         var toret;
-        this.startTransaction(metadata);
-        toret = callback.call(context);
+        params = params || {};
+        this.startTransaction(params.metadata);
+        try {
+            toret = callback.call(params.context || this);
+        } catch(e) {
+            if(params.error) {
+                params.error(e);
+            }
+            this.rollbackTransaction();
+            return;
+        }
         this.endTransaction();
         return toret;
     },