From ec8b42c5e060b191070f9b7b03eb1ca541849401 Mon Sep 17 00:00:00 2001
From: nightwing <amirjanyan@gmail.com>
Date: Mon, 17 Jun 2013 16:30:09 +0400
Subject: [PATCH] add start/endOperation

---
 lib/ace/editor.js | 62 +++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 60 insertions(+), 2 deletions(-)

diff --git a/lib/ace/editor.js b/lib/ace/editor.js
index 97e78d36..6771c0dd 100644
--- a/lib/ace/editor.js
+++ b/lib/ace/editor.js
@@ -88,7 +88,9 @@ var Editor = function(renderer, session) {
 
     this.$historyTracker = this.$historyTracker.bind(this);
     this.commands.on("exec", this.$historyTracker);
-    
+
+    this.$initOperationListeners();
+
     this.setSession(session || new EditSession(""));
     config.resetOptions(this);
     config._emit("editor", this);
@@ -97,7 +99,63 @@ var Editor = function(renderer, session) {
 (function(){
 
     oop.implement(this, EventEmitter);
-    
+
+    this.$initOperationListeners = function() {
+        function last(a) {return a[a.length - 1]};
+
+        this.selections = [];
+        this.commands.on("exec", function(e) {
+            this.startOperation(e);
+
+        }.bind(this), true);
+
+        this.commands.on("afterExec", function(e) {
+            this.endOperation(e);
+
+        }.bind(this), true);
+
+        this.$opResetTimer = lang.delayedCall(this.endOperation.bind(this));
+
+        this.on("change", function() {
+            this.curOp || this.startOperation();
+            this.curOp.docChanged = true;
+        }.bind(this), true);
+
+        this.on("changeSelection", function() {
+            this.curOp || this.startOperation();
+            this.curOp.selectionChanged = true;
+        }.bind(this), true);
+    }
+
+    this.curOp = null;
+    this.prevOp = {};
+    this.startOperation = function(commadEvent) {
+        if (this.curOp) {
+            if (!commadEvent || this.curOp.command)
+                return;
+            this.prevOp = this.curOp;
+        }
+        if (!commadEvent) {
+            this.previousCommand = null;
+            commadEvent = {};
+        }
+
+        this.$opResetTimer.schedule();
+        this.curOp = {
+            command: commadEvent.command || {},
+            args: commadEvent.args
+        };
+
+        this.selections.push(this.selection.toJSON());
+    };
+
+    this.endOperation = function() {
+        if (this.curOp) {
+            this.prevOp = this.curOp;
+            this.curOp = null;
+        }
+    };
+
     this.$historyTracker = function(e) {
         if (!this.$mergeUndoDeltas)
             return;