From aeeba4d58db862595a3219c308c89057c8167628 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=BCrg=20Lehni?= <juerg@scratchdisk.com>
Date: Tue, 18 Mar 2014 15:28:29 +0100
Subject: [PATCH] Implement ChangeFlag.INSERTION notification to know when an
 item was inserted in a new parent inside the DOM.

---
 src/item/ChangeFlag.js | 24 ++++++++++++++----------
 src/item/Item.js       | 38 ++++++++++++++++++++++++++++----------
 src/item/Layer.js      |  2 +-
 3 files changed, 43 insertions(+), 21 deletions(-)

diff --git a/src/item/ChangeFlag.js b/src/item/ChangeFlag.js
index 00ed7e30..cd6b9591 100644
--- a/src/item/ChangeFlag.js
+++ b/src/item/ChangeFlag.js
@@ -14,25 +14,27 @@ var ChangeFlag = {
 	// Anything affecting the appearance of an item, including GEOMETRY,
 	// STROKE, STYLE and ATTRIBUTE (except for the invisible ones: locked, name)
 	APPEARANCE: 0x1,
-	// Change in item hierarchy
+	// A change in the item's children
 	CHILDREN: 0x2,
+	// A change in the item's place in the DOM (removed, inserted, moved). 
+	INSERTION: 0x4,
 	// Item geometry (path, bounds)
-	GEOMETRY: 0x4,
-	// Only segment(s) have changed, and affected curves have alredy been
+	GEOMETRY: 0x8,
+	// Only segment(s) have changed, and affected curves have already been
 	// notified. This is to implement an optimization in _changed() calls.
-	SEGMENTS: 0x8,
+	SEGMENTS: 0x10,
 	// Stroke geometry (excluding color)
-	STROKE: 0x10,
+	STROKE: 0x20,
 	// Fill style or stroke color / dash
-	STYLE: 0x20,
+	STYLE: 0x40,
 	// Item attributes: visible, blendMode, locked, name, opacity, clipMask ...
-	ATTRIBUTE: 0x40,
+	ATTRIBUTE: 0x80,
 	// Text content
-	CONTENT: 0x80,
+	CONTENT: 0x100,
 	// Raster pixels
-	PIXELS: 0x100,
+	PIXELS: 0x200,
 	// Clipping in one of the child items
-	CLIPPING: 0x200
+	CLIPPING: 0x400
 };
 
 // Shortcuts to often used ChangeFlag values including APPEARANCE
@@ -40,6 +42,8 @@ var Change = {
 	// CHILDREN also changes GEOMETRY, since removing children from groups
 	// changes bounds.
 	CHILDREN: ChangeFlag.CHILDREN | ChangeFlag.GEOMETRY | ChangeFlag.APPEARANCE,
+	// Changing the insertion can change the appearance through parent's matrix.
+	INSERTION: ChangeFlag.INSERTION | ChangeFlag.APPEARANCE,
 	GEOMETRY: ChangeFlag.GEOMETRY | ChangeFlag.APPEARANCE,
 	SEGMENTS: ChangeFlag.SEGMENTS | ChangeFlag.GEOMETRY | ChangeFlag.APPEARANCE,
 	STROKE: ChangeFlag.STROKE | ChangeFlag.STYLE | ChangeFlag.APPEARANCE,
diff --git a/src/item/Item.js b/src/item/Item.js
index a355dcf0..7b1fdc8c 100644
--- a/src/item/Item.js
+++ b/src/item/Item.js
@@ -2006,10 +2006,15 @@ var Item = Base.extend(Callback, /** @lends Item# */{
 				if (_proto && !(item instanceof _proto)) {
 					items.splice(i, 1);
 				} else {
-					item._remove(true);
+					// Notify parent of change. Don't notify item itself yet,
+					// as we're doing so when adding it to the new parent below.
+					item._remove(false, true);
 				}
 			}
 			Base.splice(children, items, index, 0);
+			var project = this._project,
+				// See #_remove() for an explanation of this:
+				notifySelf = project && project._changes;
 			for (var i = 0, l = items.length; i < l; i++) {
 				var item = items[i];
 				item._parent = this;
@@ -2018,6 +2023,8 @@ var Item = Base.extend(Callback, /** @lends Item# */{
 				// are kept in sync.
 				if (item._name)
 					item.setName(item._name);
+				if (notifySelf)
+					this._changed(/*#=*/ Change.INSERTION);
 			}
 			this._changed(/*#=*/ Change.CHILDREN);
 		} else {
@@ -2164,16 +2171,24 @@ var Item = Base.extend(Callback, /** @lends Item# */{
 	/**
 	* Removes the item from its parent's children list.
 	*/
-	_remove: function(notify) {
-		if (this._parent) {
+	_remove: function(notifySelf, notifyParent) {
+		var parent = this._parent;
+		if (parent) {
 			if (this._name)
 				this._removeNamed();
 			if (this._index != null)
-				Base.splice(this._parent._children, null, this._index, 1);
+				Base.splice(parent._children, null, this._index, 1);
 			this._installEvents(false);
-			// Notify parent of changed hierarchy
-			if (notify)
-				this._parent._changed(/*#=*/ Change.CHILDREN);
+			// Notify self of the insertion change. We only need this
+			// notification if we're tracking changes for now.
+			if (notifySelf) {
+				var project = this._project;
+				if (project && project._changes)
+					this._changed(/*#=*/ Change.INSERTION);
+			}
+			// Notify parent of changed children
+			if (notifyParent)
+				parent._changed(/*#=*/ Change.CHILDREN);
 			this._parent = null;
 			return true;
 		}
@@ -2187,7 +2202,8 @@ var Item = Base.extend(Callback, /** @lends Item# */{
 	* @return {Boolean} {@true if the item was removed}
 	*/
 	remove: function() {
-		return this._remove(true);
+		// Notify self and parent of change:
+		return this._remove(true, true);
 	},
 
 	/**
@@ -2217,8 +2233,10 @@ var Item = Base.extend(Callback, /** @lends Item# */{
 		// deletes it for the removed items. Calling #_remove() afterwards is
 		// fine, since it only calls Base.splice() if #_index is set.
 		var removed = Base.splice(this._children, null, from, to - from);
-		for (var i = removed.length - 1; i >= 0; i--)
-			removed[i]._remove(false);
+		for (var i = removed.length - 1; i >= 0; i--) {
+			// Don't notify parent each time, notify it separately after.
+			removed[i]._remove(true, false);
+		}
 		if (removed.length > 0)
 			this._changed(/*#=*/ Change.CHILDREN);
 		return removed;
diff --git a/src/item/Layer.js b/src/item/Layer.js
index e4d6424e..fd4855fb 100644
--- a/src/item/Layer.js
+++ b/src/item/Layer.js
@@ -131,7 +131,7 @@ var Layer = Group.extend(/** @lends Layer# */{
 		// If the item is a layer and contained within Project#layers, use
 		// our own version of move().
 		if (item instanceof Layer && !item._parent) {
-			this._remove(true);
+			this._remove(true, true);
 			Base.splice(item._project.layers, [this],
 					item._index + (above ? 1 : 0), 0);
 			this._setProject(item._project, true);