michael@0: /* -*- Mode: Javascript; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* vim: set ft=javascript ts=2 et sw=2 tw=80: */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: "use strict";
michael@0: 
michael@0: const {Cu, Ci} = require("chrome");
michael@0: let EventEmitter = require("devtools/toolkit/event-emitter");
michael@0: 
michael@0: /**
michael@0:  * API
michael@0:  *
michael@0:  *   new Selection(walker=null, node=null, track={attributes,detached});
michael@0:  *   destroy()
michael@0:  *   node (readonly)
michael@0:  *   setNode(node, origin="unknown")
michael@0:  *
michael@0:  * Helpers:
michael@0:  *
michael@0:  *   window
michael@0:  *   document
michael@0:  *   isRoot()
michael@0:  *   isNode()
michael@0:  *   isHTMLNode()
michael@0:  *
michael@0:  * Check the nature of the node:
michael@0:  *
michael@0:  *   isElementNode()
michael@0:  *   isAttributeNode()
michael@0:  *   isTextNode()
michael@0:  *   isCDATANode()
michael@0:  *   isEntityRefNode()
michael@0:  *   isEntityNode()
michael@0:  *   isProcessingInstructionNode()
michael@0:  *   isCommentNode()
michael@0:  *   isDocumentNode()
michael@0:  *   isDocumentTypeNode()
michael@0:  *   isDocumentFragmentNode()
michael@0:  *   isNotationNode()
michael@0:  *
michael@0:  * Events:
michael@0:  *   "new-node" when the inner node changed
michael@0:  *   "before-new-node" when the inner node is set to change
michael@0:  *   "attribute-changed" when an attribute is changed (only if tracked)
michael@0:  *   "detached" when the node (or one of its parents) is removed from the document (only if tracked)
michael@0:  *   "reparented" when the node (or one of its parents) is moved under a different node (only if tracked)
michael@0:  */
michael@0: 
michael@0: /**
michael@0:  * A Selection object. Hold a reference to a node.
michael@0:  * Includes some helpers, fire some helpful events.
michael@0:  *
michael@0:  * @param node Inner node.
michael@0:  *    Can be null. Can be (un)set in the future via the "node" property;
michael@0:  * @param trackAttribute Tell if events should be fired when the attributes of
michael@0:  *    the node change.
michael@0:  *
michael@0:  */
michael@0: function Selection(walker, node=null, track={attributes:true,detached:true}) {
michael@0:   EventEmitter.decorate(this);
michael@0: 
michael@0:   this._onMutations = this._onMutations.bind(this);
michael@0:   this.track = track;
michael@0:   this.setWalker(walker);
michael@0:   this.setNode(node);
michael@0: }
michael@0: 
michael@0: exports.Selection = Selection;
michael@0: 
michael@0: Selection.prototype = {
michael@0:   _walker: null,
michael@0:   _node: null,
michael@0: 
michael@0:   _onMutations: function(mutations) {
michael@0:     let attributeChange = false;
michael@0:     let pseudoChange = false;
michael@0:     let detached = false;
michael@0:     let parentNode = null;
michael@0: 
michael@0:     for (let m of mutations) {
michael@0:       if (!attributeChange && m.type == "attributes") {
michael@0:         attributeChange = true;
michael@0:       }
michael@0:       if (m.type == "childList") {
michael@0:         if (!detached && !this.isConnected()) {
michael@0:           if (this.isNode()) {
michael@0:             parentNode = m.target;
michael@0:           }
michael@0:           detached = true;
michael@0:         }
michael@0:       }
michael@0:       if (m.type == "pseudoClassLock") {
michael@0:         pseudoChange = true;
michael@0:       }
michael@0:     }
michael@0: 
michael@0:     // Fire our events depending on what changed in the mutations array
michael@0:     if (attributeChange) {
michael@0:       this.emit("attribute-changed");
michael@0:     }
michael@0:     if (pseudoChange) {
michael@0:       this.emit("pseudoclass");
michael@0:     }
michael@0:     if (detached) {
michael@0:       let rawNode = null;
michael@0:       if (parentNode && parentNode.isLocal_toBeDeprecated()) {
michael@0:         rawNode = parentNode.rawNode();
michael@0:       }
michael@0: 
michael@0:       this.emit("detached", rawNode, null);
michael@0:       this.emit("detached-front", parentNode);
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   destroy: function() {
michael@0:     this.setNode(null);
michael@0:     this.setWalker(null);
michael@0:   },
michael@0: 
michael@0:   setWalker: function(walker) {
michael@0:     if (this._walker) {
michael@0:       this._walker.off("mutations", this._onMutations);
michael@0:     }
michael@0:     this._walker = walker;
michael@0:     if (this._walker) {
michael@0:       this._walker.on("mutations", this._onMutations);
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   // Not remote-safe
michael@0:   setNode: function(value, reason="unknown") {
michael@0:     if (value) {
michael@0:       value = this._walker.frontForRawNode(value);
michael@0:     }
michael@0:     this.setNodeFront(value, reason);
michael@0:   },
michael@0: 
michael@0:   // Not remote-safe
michael@0:   get node() {
michael@0:     return this._node;
michael@0:   },
michael@0: 
michael@0:   // Not remote-safe
michael@0:   get window() {
michael@0:     if (this.isNode()) {
michael@0:       return this.node.ownerDocument.defaultView;
michael@0:     }
michael@0:     return null;
michael@0:   },
michael@0: 
michael@0:   // Not remote-safe
michael@0:   get document() {
michael@0:     if (this.isNode()) {
michael@0:       return this.node.ownerDocument;
michael@0:     }
michael@0:     return null;
michael@0:   },
michael@0: 
michael@0:   setNodeFront: function(value, reason="unknown") {
michael@0:     this.reason = reason;
michael@0: 
michael@0:     // We used to return here if the node had not changed but we now need to
michael@0:     // set the node even if it is already set otherwise it is not possible to
michael@0:     // e.g. highlight the same node twice.
michael@0:     let rawValue = null;
michael@0:     if (value && value.isLocal_toBeDeprecated()) {
michael@0:       rawValue = value.rawNode();
michael@0:     }
michael@0:     this.emit("before-new-node", rawValue, reason);
michael@0:     this.emit("before-new-node-front", value, reason);
michael@0:     let previousNode = this._node;
michael@0:     let previousFront = this._nodeFront;
michael@0:     this._node = rawValue;
michael@0:     this._nodeFront = value;
michael@0:     this.emit("new-node", previousNode, this.reason);
michael@0:     this.emit("new-node-front", value, this.reason);
michael@0:   },
michael@0: 
michael@0:   get documentFront() {
michael@0:     return this._walker.document(this._nodeFront);
michael@0:   },
michael@0: 
michael@0:   get nodeFront() {
michael@0:     return this._nodeFront;
michael@0:   },
michael@0: 
michael@0:   isRoot: function() {
michael@0:     return this.isNode() &&
michael@0:            this.isConnected() &&
michael@0:            this._nodeFront.isDocumentElement;
michael@0:   },
michael@0: 
michael@0:   isNode: function() {
michael@0:     if (!this._nodeFront) {
michael@0:       return false;
michael@0:     }
michael@0: 
michael@0:     // As long as tools are still accessing node.rawNode(),
michael@0:     // this needs to stay here.
michael@0:     if (this._node && Cu.isDeadWrapper(this._node)) {
michael@0:       return false;
michael@0:     }
michael@0: 
michael@0:     return true;
michael@0:   },
michael@0: 
michael@0:   isLocal: function() {
michael@0:     return !!this._node;
michael@0:   },
michael@0: 
michael@0:   isConnected: function() {
michael@0:     let node = this._nodeFront;
michael@0:     if (!node || !node.actorID) {
michael@0:       return false;
michael@0:     }
michael@0: 
michael@0:     // As long as there are still tools going around
michael@0:     // accessing node.rawNode, this needs to stay.
michael@0:     let rawNode = null;
michael@0:     if (node.isLocal_toBeDeprecated()) {
michael@0:       rawNode = node.rawNode();
michael@0:     }
michael@0:     if (rawNode) {
michael@0:       try {
michael@0:         let doc = this.document;
michael@0:         return (doc && doc.defaultView && doc.documentElement.contains(rawNode));
michael@0:       } catch (e) {
michael@0:         // "can't access dead object" error
michael@0:         return false;
michael@0:       }
michael@0:     }
michael@0: 
michael@0:     while(node) {
michael@0:       if (node === this._walker.rootNode) {
michael@0:         return true;
michael@0:       }
michael@0:       node = node.parentNode();
michael@0:     };
michael@0:     return false;
michael@0:   },
michael@0: 
michael@0:   isHTMLNode: function() {
michael@0:     let xhtml_ns = "http://www.w3.org/1999/xhtml";
michael@0:     return this.isNode() && this.node.namespaceURI == xhtml_ns;
michael@0:   },
michael@0: 
michael@0:   // Node type
michael@0: 
michael@0:   isElementNode: function() {
michael@0:     return this.isNode() && this.nodeFront.nodeType == Ci.nsIDOMNode.ELEMENT_NODE;
michael@0:   },
michael@0: 
michael@0:   isAttributeNode: function() {
michael@0:     return this.isNode() && this.nodeFront.nodeType == Ci.nsIDOMNode.ATTRIBUTE_NODE;
michael@0:   },
michael@0: 
michael@0:   isTextNode: function() {
michael@0:     return this.isNode() && this.nodeFront.nodeType == Ci.nsIDOMNode.TEXT_NODE;
michael@0:   },
michael@0: 
michael@0:   isCDATANode: function() {
michael@0:     return this.isNode() && this.nodeFront.nodeType == Ci.nsIDOMNode.CDATA_SECTION_NODE;
michael@0:   },
michael@0: 
michael@0:   isEntityRefNode: function() {
michael@0:     return this.isNode() && this.nodeFront.nodeType == Ci.nsIDOMNode.ENTITY_REFERENCE_NODE;
michael@0:   },
michael@0: 
michael@0:   isEntityNode: function() {
michael@0:     return this.isNode() && this.nodeFront.nodeType == Ci.nsIDOMNode.ENTITY_NODE;
michael@0:   },
michael@0: 
michael@0:   isProcessingInstructionNode: function() {
michael@0:     return this.isNode() && this.nodeFront.nodeType == Ci.nsIDOMNode.PROCESSING_INSTRUCTION_NODE;
michael@0:   },
michael@0: 
michael@0:   isCommentNode: function() {
michael@0:     return this.isNode() && this.nodeFront.nodeType == Ci.nsIDOMNode.PROCESSING_INSTRUCTION_NODE;
michael@0:   },
michael@0: 
michael@0:   isDocumentNode: function() {
michael@0:     return this.isNode() && this.nodeFront.nodeType == Ci.nsIDOMNode.DOCUMENT_NODE;
michael@0:   },
michael@0: 
michael@0:   isDocumentTypeNode: function() {
michael@0:     return this.isNode() && this.nodeFront.nodeType == Ci.nsIDOMNode.DOCUMENT_TYPE_NODE;
michael@0:   },
michael@0: 
michael@0:   isDocumentFragmentNode: function() {
michael@0:     return this.isNode() && this.nodeFront.nodeType == Ci.nsIDOMNode.DOCUMENT_FRAGMENT_NODE;
michael@0:   },
michael@0: 
michael@0:   isNotationNode: function() {
michael@0:     return this.isNode() && this.nodeFront.nodeType == Ci.nsIDOMNode.NOTATION_NODE;
michael@0:   },
michael@0: };