editor: improving onAfterActionExecuted canvas handler - handle actions returning...
[fnpeditor.git] / src / editor / modules / documentCanvas / canvas / canvas.js
index 6a60f80..7599a71 100644 (file)
@@ -2,15 +2,19 @@ define([
 'libs/jquery',
 'libs/underscore',
 'libs/backbone',
 'libs/jquery',
 'libs/underscore',
 'libs/backbone',
+'fnpjs/logging/logging',
 'modules/documentCanvas/canvas/documentElement',
 'modules/documentCanvas/canvas/keyboard',
 'modules/documentCanvas/canvas/utils',
 'modules/documentCanvas/canvas/documentElement',
 'modules/documentCanvas/canvas/keyboard',
 'modules/documentCanvas/canvas/utils',
-'modules/documentCanvas/canvas/wlxmlListener'
-], function($, _, Backbone, documentElement, keyboard, utils, wlxmlListener) {
+'modules/documentCanvas/canvas/wlxmlListener',
+'modules/documentCanvas/canvas/elementsRegister',
+'modules/documentCanvas/canvas/genericElement',
+], function($, _, Backbone, logging, documentElement, keyboard, utils, wlxmlListener, ElementsRegister, genericElement) {
     
 'use strict';
     
 'use strict';
-/* global document:false, window:false */
+/* global document:false, window:false, Node:false, gettext */
 
 
+var logger = logging.getLogger('canvas');
 
 var TextHandler = function(canvas) {this.canvas = canvas; this.buffer = null;};
 $.extend(TextHandler.prototype, {
 
 var TextHandler = function(canvas) {this.canvas = canvas; this.buffer = null;};
 $.extend(TextHandler.prototype, {
@@ -40,23 +44,42 @@ $.extend(TextHandler.prototype, {
     },
     setText: function(text, node) {
         //this.canvas.wlxmlDocument.transform('setText', {node:node, text: text});
     },
     setText: function(text, node) {
         //this.canvas.wlxmlDocument.transform('setText', {node:node, text: text});
-        node.setText(text);
+        node.document.transaction(function() {
+            node.setText(text);
+        }, {
+            metadata:{
+                description: gettext('Changing text')
+            }
+        });
 
     }
 
 });
 
 
 
     }
 
 });
 
 
-var Canvas = function(wlxmlDocument, publisher) {
+var Canvas = function(wlxmlDocument, elements) {
+    this.elementsRegister = new ElementsRegister(documentElement.DocumentNodeElement);
+
+    elements = [
+        {tag: 'section', klass: null, prototype: genericElement},
+        {tag: 'div', klass: null, prototype: genericElement},
+        {tag: 'header', klass: null, prototype: genericElement},
+        {tag: 'span', klass: null, prototype: genericElement},
+        {tag: 'aside', klass: null, prototype: genericElement}
+    ].concat(elements || []);
+
+    (elements).forEach(function(elementDesc) {
+        this.elementsRegister.register(elementDesc);
+    }.bind(this));
     this.eventBus = _.extend({}, Backbone.Events);
     this.wrapper = $('<div>').addClass('canvas-wrapper').attr('contenteditable', true);
     this.wlxmlListener = wlxmlListener.create(this);
     this.loadWlxmlDocument(wlxmlDocument);
     this.eventBus = _.extend({}, Backbone.Events);
     this.wrapper = $('<div>').addClass('canvas-wrapper').attr('contenteditable', true);
     this.wlxmlListener = wlxmlListener.create(this);
     this.loadWlxmlDocument(wlxmlDocument);
-    this.publisher = publisher ? publisher : function() {};
+    this.setupEventHandling();
     this.textHandler = new TextHandler(this);
 };
 
     this.textHandler = new TextHandler(this);
 };
 
-$.extend(Canvas.prototype, {
+$.extend(Canvas.prototype, Backbone.Events, {
 
     loadWlxmlDocument: function(wlxmlDocument) {
         if(!wlxmlDocument) {
 
     loadWlxmlDocument: function(wlxmlDocument) {
         if(!wlxmlDocument) {
@@ -66,34 +89,95 @@ $.extend(Canvas.prototype, {
         this.wlxmlListener.listenTo(wlxmlDocument);
         this.wlxmlDocument = wlxmlDocument;
         this.reloadRoot();
         this.wlxmlListener.listenTo(wlxmlDocument);
         this.wlxmlDocument = wlxmlDocument;
         this.reloadRoot();
-        this.setupEventHandling();
     },
 
     },
 
-    reloadRoot: function() {
-        var canvasDOM = this.generateCanvasDOM(this.wlxmlDocument.root);
-        //var canvasDOM = this.wlxmlDocument.root.getData('canvasElement') ? this.wlxmlDocument.root.getData('canvasElement').dom() : this.generateCanvasDOM(this.wlxmlDocument.root);
+    createElement: function(wlxmlNode) {
+        var Factory;
+        if(wlxmlNode.nodeType === Node.TEXT_NODE) {
+            Factory = documentElement.DocumentTextElement;
+        } else {
+            Factory = this.elementsRegister.getElement({tag: wlxmlNode.getTagName(), klass: wlxmlNode.getClass()});
+        }
+        return new Factory(wlxmlNode, this);
+    },
 
 
-        this.wrapper.empty();
-        this.wrapper.append(canvasDOM);
-        this.d = this.wrapper.children(0);
+    getDocumentElement: function(htmlElement) {
+        /* globals HTMLElement, Text */
+        if(!htmlElement || !(htmlElement instanceof HTMLElement || htmlElement instanceof Text)) {
+            return null;
+        }
+        var $element = $(htmlElement);
+        if(htmlElement.nodeType === Node.ELEMENT_NODE && $element.attr('document-node-element') !== undefined) {
+            return $element.data('canvas-element');
+        }
+
+        if(htmlElement.nodeType === Node.TEXT_NODE && $element.parent().attr('document-text-element') !== undefined) {
+            $element = $element.parent();
+        }
+
+        if($element.attr('document-text-element') !== undefined || (htmlElement.nodeType === Node.TEXT_NODE && $element.parent().attr('document-text-element') !== undefined)) {
+            //return DocumentTextElement.fromHTMLElement(htmlElement, canvas);
+            return $element.data('canvas-element');
+        }
     },
 
     },
 
-    generateCanvasDOM: function(wlxmlNode) {
-        var element = documentElement.DocumentNodeElement.create(wlxmlNode, this);
-        return element.dom();
+    reloadRoot: function() {
+        this.rootElement = this.createElement(this.wlxmlDocument.root);
+        this.wrapper.empty();
+        this.wrapper.append(this.rootElement.dom);
     },
 
     setupEventHandling: function() {
         var canvas = this;
     },
 
     setupEventHandling: function() {
         var canvas = this;
+
         this.wrapper.on('keyup keydown keypress', function(e) {
         this.wrapper.on('keyup keydown keypress', function(e) {
-            keyboard.handleKey(e, this);
-        }.bind(this));
+            keyboard.handleKey(e, canvas);
+        });
+
+        this.wrapper.on('mouseup', function() {
+            canvas.triggerSelectionChanged();
+        });
+
+        var mouseDown;
+        this.wrapper.on('mousedown', '[document-node-element], [document-text-element]', function(e) {
+            mouseDown = e.target;
+        });
 
         this.wrapper.on('click', '[document-node-element], [document-text-element]', function(e) {
             e.stopPropagation();
 
         this.wrapper.on('click', '[document-node-element], [document-text-element]', function(e) {
             e.stopPropagation();
-            canvas.setCurrentElement(canvas.getDocumentElement(e.currentTarget), {caretTo: false});
+            if(e.originalEvent.detail === 3) {
+                e.preventDefault();
+                canvas._moveCaretToTextElement(canvas.getDocumentElement(e.currentTarget), 'whole');
+            } else {
+                if(mouseDown === e.target) {
+                    canvas.setCurrentElement(canvas.getDocumentElement(e.currentTarget), {caretTo: false});
+                }
+            }
         });
 
         });
 
+        this.wrapper.on('paste', function(e) {
+            e.preventDefault();
+
+            var clipboardData = e.originalEvent.clipboardData;
+            if(!clipboardData || !clipboardData.getData) {
+                return; // TODO: alert
+            }
+
+            var text = clipboardData.getData('text/plain').replace(/\r?\n|\r/g, ' '),
+                cursor = canvas.getCursor(),
+                element = cursor.getPosition().element,
+                lhs, rhs;
+            
+            if(element && cursor.isWithinElement()) {
+                lhs = element.getText().substr(0, cursor.getSelectionStart().offset);
+                rhs = element.getText().substr(cursor.getSelectionEnd().offset);
+                element.setText(lhs+text+rhs);
+                canvas.setCurrentElement(element, {caretTo: lhs.length + text.length});
+            } else {
+                /* jshint noempty:false */
+                // TODO: alert
+            }
+        });
 
         /* globals MutationObserver */
         var observer = new MutationObserver(function(mutations) {
 
         /* globals MutationObserver */
         var observer = new MutationObserver(function(mutations) {
@@ -108,15 +192,14 @@ $.extend(Canvas.prototype, {
                         canvas._moveCaretToTextElement(canvas.getDocumentElement(mutation.target), 'end');
                     }
                     observer.observe(canvas.wrapper[0], config);
                         canvas._moveCaretToTextElement(canvas.getDocumentElement(mutation.target), 'end');
                     }
                     observer.observe(canvas.wrapper[0], config);
-                    canvas.publisher('contentChanged');
 
                     var textElement = canvas.getDocumentElement(mutation.target),
                         toSet = mutation.target.data !== utils.unicode.ZWS ? mutation.target.data : '';
 
                     //textElement.data('wlxmlNode').setText(toSet);
                     //textElement.data('wlxmlNode').document.transform('setText', {node: textElement.data('wlxmlNode'), text: toSet});
 
                     var textElement = canvas.getDocumentElement(mutation.target),
                         toSet = mutation.target.data !== utils.unicode.ZWS ? mutation.target.data : '';
 
                     //textElement.data('wlxmlNode').setText(toSet);
                     //textElement.data('wlxmlNode').document.transform('setText', {node: textElement.data('wlxmlNode'), text: toSet});
-                    if(textElement.data('wlxmlNode').getText() !== toSet) {
-                        canvas.textHandler.handle(textElement.data('wlxmlNode'), toSet);
+                    if(textElement.wlxmlNode.getText() !== toSet) {
+                        canvas.textHandler.handle(textElement.wlxmlNode, toSet);
                     }
                 }
             });
                     }
                 }
             });
@@ -150,7 +233,7 @@ $.extend(Canvas.prototype, {
 
         this.eventBus.on('elementToggled', function(toggle, element) {
             if(!toggle) {
 
         this.eventBus.on('elementToggled', function(toggle, element) {
             if(!toggle) {
-                canvas.setCurrentElement(element.getPreviousTextElement());
+                canvas.setCurrentElement(canvas.getPreviousTextElement(element));
             }
         });
     },
             }
         });
     },
@@ -160,45 +243,85 @@ $.extend(Canvas.prototype, {
     },
 
     doc: function() {
     },
 
     doc: function() {
-        if(this.d === null) {
-            return null;
-        }
-        return documentElement.DocumentNodeElement.fromHTMLElement(this.d.get(0), this); //{wlxmlTag: this.d.prop('tagName')};
+        return this.rootElement;
     },
 
     toggleElementHighlight: function(node, toggle) {
     },
 
     toggleElementHighlight: function(node, toggle) {
-        var element = utils.findCanvasElement(node);
+        var element = utils.getElementForNode(node);
         element.toggleHighlight(toggle);
     },
 
         element.toggleHighlight(toggle);
     },
 
-    createNodeElement: function(params) {
-        return documentElement.DocumentNodeElement.create(params, this);
-    },
-
-    getDocumentElement: function(from) {
-        /* globals HTMLElement, Text */
-        if(from instanceof HTMLElement || from instanceof Text) {
-           return documentElement.DocumentElement.fromHTMLElement(from, this);
-        }
-    },
     getCursor: function() {
         return new Cursor(this);
     },
 
     
     getCurrentNodeElement: function() {
     getCursor: function() {
         return new Cursor(this);
     },
 
     
     getCurrentNodeElement: function() {
-        return this.getDocumentElement(this.wrapper.find('.current-node-element').parent()[0]);
+        var htmlElement = this.wrapper.find('.current-node-element').parent()[0];
+        if(htmlElement) {
+            return this.getDocumentElement(htmlElement);
+        }
     },
 
     getCurrentTextElement: function() {
     },
 
     getCurrentTextElement: function() {
-        return this.getDocumentElement(this.wrapper.find('.current-text-element')[0]);
+        var htmlElement = this.wrapper.find('.current-text-element')[0];
+        if(htmlElement) {
+            return this.getDocumentElement(htmlElement);
+        }
+    },
+
+    getPreviousTextElement: function(relativeToElement, includeInvisible) {
+        return this.getNearestTextElement('above', relativeToElement, includeInvisible);
+    },
+
+    getNextTextElement: function(relativeToElement, includeInvisible) {
+        return this.getNearestTextElement('below', relativeToElement, includeInvisible);
     },
 
     },
 
+    getNearestTextElement: function(direction, relativeToElement, includeInvisible) {
+        includeInvisible = includeInvisible !== undefined ? includeInvisible : false;
+        var selector = '[document-text-element]' + (includeInvisible ? '' : ':visible');
+        return this.getDocumentElement(utils.nearestInDocumentOrder(selector, direction, relativeToElement.dom[0]));
+    },
+
+    contains: function(element) {
+        return element.dom.parents().index(this.wrapper) !== -1;
+    },
+
+    triggerSelectionChanged: function() {
+        this.trigger('selectionChanged', this.getSelection());
+        var s = this.getSelection(),
+            f = s.toDocumentFragment();
+        if(f && f instanceof f.RangeFragment) {
+                var $current = this.wrapper.find('.current-node-element');
+                var current = $current && this.getDocumentElement($current.parent()[0]);
+                
+                if($current) {
+                    $current.removeClass('current-node-element');
+                }
+                if(current) {
+                    current.markAsCurrent(false);
+                }
+        }
+    },
 
 
+    getSelection: function() {
+        return new Selection(this);
+    },
 
     setCurrentElement: function(element, params) {
 
     setCurrentElement: function(element, params) {
+        if(!element) {
+            logger.debug('Invalid element passed to setCurrentElement: ' + element);
+            return;
+        }
+
         if(!(element instanceof documentElement.DocumentElement)) {
         if(!(element instanceof documentElement.DocumentElement)) {
-            element = utils.findCanvasElement(element);
+            element = utils.getElementForNode(element);
+        }
+
+        if(!element || !this.contains(element)) {
+            logger.warning('Cannot set current element: element doesn\'t exist on canvas');
+            return;
         }
 
         params = _.extend({caretTo: 'end'}, params);
         }
 
         params = _.extend({caretTo: 'end'}, params);
@@ -207,22 +330,22 @@ $.extend(Canvas.prototype, {
             if(byBrowser && byBrowser.parent().sameNode(nodeToLand)) {
                 return byBrowser;
             }
             if(byBrowser && byBrowser.parent().sameNode(nodeToLand)) {
                 return byBrowser;
             }
-            var children = e.children();
-            for(var i = 0; i < children.length; i++) {
-                if(children[i] instanceof documentElement.DocumentTextElement) {
-                    return children[i];
-                }
-            }
-            return null;
+            return e.getVerticallyFirstTextElement();
         }.bind(this);
         var _markAsCurrent = function(element) {
             if(element instanceof documentElement.DocumentTextElement) {
                 this.wrapper.find('.current-text-element').removeClass('current-text-element');
         }.bind(this);
         var _markAsCurrent = function(element) {
             if(element instanceof documentElement.DocumentTextElement) {
                 this.wrapper.find('.current-text-element').removeClass('current-text-element');
-                element.dom().addClass('current-text-element');
+                element.dom.addClass('current-text-element');
             } else {
             } else {
-                this.wrapper.find('.current-node-element').removeClass('current-node-element');
+                var $current = this.wrapper.find('.current-node-element');
+                var current = this.getDocumentElement($current.parent()[0]);
+                $current.removeClass('current-node-element');
+
+                if(current) {
+                    current.markAsCurrent(false);
+                }
                 element._container().addClass('current-node-element');
                 element._container().addClass('current-node-element');
-                this.publisher('currentElementChanged', element);
+                element.markAsCurrent(true);
             }
         }.bind(this);
 
             }
         }.bind(this);
 
@@ -242,36 +365,33 @@ $.extend(Canvas.prototype, {
             if(params.caretTo || !textElementToLand.sameNode(this.getCursor().getPosition().element)) {
                 this._moveCaretToTextElement(textElementToLand, params.caretTo); // as method on element?
             }
             if(params.caretTo || !textElementToLand.sameNode(this.getCursor().getPosition().element)) {
                 this._moveCaretToTextElement(textElementToLand, params.caretTo); // as method on element?
             }
-            if(!(textElementToLand.sameNode(currentTextElement))) {
-                this.publisher('currentTextElementSet', textElementToLand.data('wlxmlNode'));
-            }
         } else {
             document.getSelection().removeAllRanges();
         }
 
         if(!(currentNodeElement && currentNodeElement.sameNode(nodeElementToLand))) {
             _markAsCurrent(nodeElementToLand);
         } else {
             document.getSelection().removeAllRanges();
         }
 
         if(!(currentNodeElement && currentNodeElement.sameNode(nodeElementToLand))) {
             _markAsCurrent(nodeElementToLand);
-
-            this.publisher('currentNodeElementSet', nodeElementToLand.data('wlxmlNode'));
         }
         }
+        this.triggerSelectionChanged();
     },
 
     _moveCaretToTextElement: function(element, where) {
         var range = document.createRange(),
     },
 
     _moveCaretToTextElement: function(element, where) {
         var range = document.createRange(),
-            node = element.dom().contents()[0];
+            node = element.dom.contents()[0];
 
         if(typeof where !== 'number') {
             range.selectNodeContents(node);
         } else {
 
         if(typeof where !== 'number') {
             range.selectNodeContents(node);
         } else {
-            range.setStart(node, where);
+            range.setStart(node, Math.min(node.data.length, where));
         }
         
         }
         
-        var collapseArg = true;
-        if(where === 'end') {
-            collapseArg = false;
+        if(where !== 'whole') {
+            var collapseArg = true;
+            if(where === 'end') {
+                collapseArg = false;
+            }
+            range.collapse(collapseArg);
         }
         }
-        range.collapse(collapseArg);
-        
         var selection = document.getSelection();
 
         selection.removeAllRanges();
         var selection = document.getSelection();
 
         selection.removeAllRanges();
@@ -283,15 +403,99 @@ $.extend(Canvas.prototype, {
         if(position.element) {
             this._moveCaretToTextElement(position.element, position.offset);
         }
         if(position.element) {
             this._moveCaretToTextElement(position.element, position.offset);
         }
+    },
+
+    toggleGrid: function() {
+        this.wrapper.toggleClass('grid-on');
+        this.trigger('changed');
+    },
+    isGridToggled: function() {
+        return this.wrapper.hasClass('grid-on');
     }
 });
 
 
     }
 });
 
 
+var isText = function(node) {
+    return node && node.nodeType === Node.TEXT_NODE && $(node.parentNode).is('[document-text-element]');
+};
+
+var Selection = function(canvas) {
+    this.canvas = canvas;
+    var nativeSelection = this.nativeSelection = window.getSelection();
+    Object.defineProperty(this, 'type', {
+        get: function() {
+            if(nativeSelection.focusNode) {
+                if(nativeSelection.isCollapsed && isText(nativeSelection.focusNode)) {
+                    return 'caret';
+                }
+                if(isText(nativeSelection.focusNode) && isText(nativeSelection.anchorNode)) {
+                    return 'textSelection';
+                }
+            }
+            if(canvas.getCurrentNodeElement()) {
+                return 'node';
+            }
+        }
+    });
+};
+
+$.extend(Selection.prototype, {
+    toDocumentFragment: function() {
+        var doc = this.canvas.wlxmlDocument,
+            anchorElement = this.canvas.getDocumentElement(this.nativeSelection.anchorNode),
+            focusElement = this.canvas.getDocumentElement(this.nativeSelection.focusNode),
+            anchorNode = anchorElement ? anchorElement.wlxmlNode : null,
+            focusNode = focusElement ? focusElement.wlxmlNode : null;
+        if(this.type === 'caret') {
+            return doc.createFragment(doc.CaretFragment, {node: anchorNode, offset: this.nativeSelection.anchorOffset});
+        }
+        if(this.type === 'textSelection') {
+            if(anchorNode.isSiblingOf(focusNode)) {
+                return doc.createFragment(doc.TextRangeFragment, {
+                    node1: anchorNode,
+                    offset1: this.nativeSelection.anchorOffset,
+                    node2: focusNode,
+                    offset2: this.nativeSelection.focusOffset,
+                });
+            }
+            else {
+                var siblingParents = doc.getSiblingParents({node1: anchorNode, node2: focusNode});
+                return doc.createFragment(doc.RangeFragment, {
+                    node1: siblingParents.node1,
+                    node2: siblingParents.node2
+                });
+            }
+        }
+        if(this.type === 'node') {
+            return doc.createFragment(doc.NodeFragment, {node: this.canvas.getCurrentNodeElement().wlxmlNode});
+        }
+    },
+    sameAs: function(other) {
+        void(other);
+    }
+});
+
 var Cursor = function(canvas) {
     this.canvas = canvas;
 var Cursor = function(canvas) {
     this.canvas = canvas;
+    this.selection = window.getSelection();
 };
 
 $.extend(Cursor.prototype, {
 };
 
 $.extend(Cursor.prototype, {
+    sameAs: function(other) {
+        var same = true;
+        if(!other) {
+            return false;
+        }
+
+        ['focusNode', 'focusOffset', 'anchorNode', 'anchorOffset'].some(function(prop) {
+            same = same && this.selection[prop] === other.selection[prop];
+            if(!same) {
+                return true; // break
+            }
+        }.bind(this));
+
+        return same;
+    },
     isSelecting: function() {
         var selection = window.getSelection();
         return !selection.isCollapsed;
     isSelecting: function() {
         var selection = window.getSelection();
         return !selection.isCollapsed;
@@ -299,6 +503,9 @@ $.extend(Cursor.prototype, {
     isSelectingWithinElement: function() {
         return this.isSelecting() && this.getSelectionStart().element.sameNode(this.getSelectionEnd().element);
     },
     isSelectingWithinElement: function() {
         return this.isSelecting() && this.getSelectionStart().element.sameNode(this.getSelectionEnd().element);
     },
+    isWithinElement: function() {
+        return !this.isSelecting() || this.isSelectingWithinElement();
+    },
     isSelectingSiblings: function() {
         return this.isSelecting() && this.getSelectionStart().element.parent().sameNode(this.getSelectionEnd().element.parent());
     },
     isSelectingSiblings: function() {
         return this.isSelecting() && this.getSelectionStart().element.parent().sameNode(this.getSelectionEnd().element.parent());
     },
@@ -331,25 +538,21 @@ $.extend(Cursor.prototype, {
             return {
                 element: anchorElement,
                 offset: selection.anchorOffset,
             return {
                 element: anchorElement,
                 offset: selection.anchorOffset,
-                offsetAtBeginning: selection.anchorOffset === 0,
-                offsetAtEnd: selection.anchorNode.data.length === selection.anchorOffset
+                offsetAtBeginning: selection.anchorOffset === 0 || anchorElement.getText() === '',
+                offsetAtEnd: selection.anchorNode.data.length === selection.anchorOffset || anchorElement.getText() === ''
             };
         }
         if(which === 'focus') {
             return {
                 element: focusElement,
                 offset: selection.focusOffset,
             };
         }
         if(which === 'focus') {
             return {
                 element: focusElement,
                 offset: selection.focusOffset,
-                offsetAtBeginning: selection.focusOffset === 0,
-                offsetAtEnd: selection.focusNode.data.length === selection.focusOffset
+                offsetAtBeginning: selection.focusOffset === 0 || focusElement.getText() === '',
+                offsetAtEnd: selection.focusNode.data.length === selection.focusOffset || focusElement.getText() === '',
             };
         }
         
             };
         }
         
-        var element,
-            offset;
-
-        if(anchorElement.parent().sameNode(focusElement.parent())) {
-            var parent = anchorElement.parent(),
-                anchorFirst = parent.childIndex(anchorElement) < parent.childIndex(focusElement);
+        var getPlaceData = function(anchorFirst) {
+            var element, offset;
             if(anchorFirst) {
                 if(which === 'start') {
                     element = anchorElement;
             if(anchorFirst) {
                 if(which === 'start') {
                     element = anchorElement;
@@ -369,30 +572,38 @@ $.extend(Cursor.prototype, {
                     offset = selection.anchorOffset;
                 }
             }
                     offset = selection.anchorOffset;
                 }
             }
-        } else {
-            // TODO: Handle order via https://developer.mozilla.org/en-US/docs/Web/API/Node.compareDocumentPosition
-            if(which === 'start') {
-                element = anchorElement;
-                offset = selection.anchorOffset;
+            return {element: element, offset: offset};
+        };
+
+        var anchorFirst, placeData, parent;
+
+        if(anchorElement.parent().sameNode(focusElement.parent())) {
+            parent = anchorElement.parent();
+            if(selection.anchorNode === selection.focusNode) {
+                anchorFirst = selection.anchorOffset <= selection.focusOffset;
             } else {
             } else {
-                element = focusElement;
-                offset = selection.focusOffset;
+                anchorFirst = (parent.getFirst(anchorElement, focusElement) === anchorElement);
             }
             }
+            placeData = getPlaceData(anchorFirst);
+        } else {
+            /*jshint bitwise: false*/
+            anchorFirst = selection.anchorNode.compareDocumentPosition(selection.focusNode) & Node.DOCUMENT_POSITION_FOLLOWING;
+            placeData = getPlaceData(anchorFirst);
         }
 
         }
 
-        var nodeLen = (element.sameNode(focusElement) ? selection.focusNode : selection.anchorNode).length;
+        var nodeLen = (placeData.element.sameNode(focusElement) ? selection.focusNode : selection.anchorNode).length;
         return {
         return {
-            element: element,
-            offset: offset,
-            offsetAtBeginning: offset === 0,
-            offsetAtEnd: nodeLen === offset
+            element: placeData.element,
+            offset: placeData.offset,
+            offsetAtBeginning: placeData.offset === 0 || focusElement.getText() === '',
+            offsetAtEnd: nodeLen === placeData.offset || focusElement.getText() === ''
         };
     }
 });
 
 return {
         };
     }
 });
 
 return {
-    fromXMLDocument: function(wlxmlDocument, publisher) {
-        return new Canvas(wlxmlDocument, publisher);
+    fromXMLDocument: function(wlxmlDocument, elements) {
+        return new Canvas(wlxmlDocument, elements);
     }
 };
 
     }
 };