var Document = function(xml, extensions) {
this.undoStack = [];
this.redoStack = [];
- this._transactionStack = [];
+ this._currentTransaction = null;
this._transformationLevel = 0;
this._nodeMethods = {};
transform: function(Transformation, args) {
var toret, transformation;
+ if(!this._currentTransaction) {
+ return this.transaction(function() {
+ return this.transform(Transformation, args);
+ }, this);
+ }
+
if(typeof Transformation === 'function') {
transformation = new Transformation(this, this, args);
} else {
},
function() {
if(this._transformationLevel === 1 && !this._undoInProgress) {
- if(this._transactionInProgress) {
- this._transactionStack.push(transformation);
- } else {
- this.undoStack.push(new Transaction([transformation]));
- }
- }
- if(!this._undoInProgress && this._transformationLevel === 1) {
+ this._currentTransaction.pushTransformation(transformation);
this.redoStack = [];
}
}
}
},
- startTransaction: function() {
- if(this._transactionInProgress) {
+ startTransaction: function(metadata) {
+ if(this._currentTransaction) {
throw new Error('Nested transactions not supported!');
}
- this._transactionInProgress = true;
+ this._rollbackBackup = this.root.clone();
+ this._currentTransaction = new Transaction([], metadata);
},
endTransaction: function() {
- if(!this._transactionInProgress) {
+ if(!this._currentTransaction) {
throw new Error('End of transaction requested, but there is no transaction in progress!');
}
- this._transactionInProgress = false;
- if(this._transactionStack.length) {
- this.undoStack.push(new Transaction(this._transactionStack));
- this._transactionStack = [];
+ if(this._currentTransaction.hasTransformations()) {
+ this.undoStack.push(this._currentTransaction);
+ }
+ this._currentTransaction = null;
+ },
+
+ 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, context) {
+ transaction: function(callback, params) {
var toret;
- this.startTransaction();
- 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;
},
}
});
-var Transaction = function(transformations) {
+var Transaction = function(transformations, metadata) {
this.transformations = transformations || [];
+ this.metadata = metadata;
};
+$.extend(Transaction.prototype, {
+ pushTransformation: function(transformation) {
+ this.transformations.push(transformation);
+ },
+ hasTransformations: function() {
+ return this.transformations.length > 0;
+ }
+});
return {