mediawiki-extensions-Visual.../modules/ve/ve.Node.js

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/**
* Generic node.
*
* @class
* @abstract
* @constructor
* @extends {ve.EventEmitter}
* @param {String} type Symbolic name of node type
*/
ve.Node = function( type ) {
// Inheritance
ve.EventEmitter.call( this );
// Properties
this.type = type;
this.parent = null;
this.root = this;
this.doc = null;
// Convenience function for emitting update events - context is bound by enclosing this scope
// making it easy to pass through other functions as a callback
var _this = this;
this.emitUpdate = function() {
_this.emit( 'update' );
};
};
/* Abstract Methods */
/**
* Checks if node can have children.
*
* @method
* @abstract
* @returns {Boolean} Node can have children
* @throws {Error} if not overridden
*/
ve.Node.prototype.canHaveChildren = function() {
throw 've.Node.canHaveChildren must be overridden in subclass';
};
/**
* Checks if node can have grandchildren.
*
* @method
* @abstract
* @returns {Boolean} Node can have grandchildren
* @throws {Error} if not overridden
*/
ve.Node.prototype.canHaveGrandchildren = function() {
throw 've.Node.canHaveGrandchildren must be overridden in subclass';
};
/**
* Checks if node represents a wrapped element.
*
* @method
* @abstract
* @returns {Boolean} Node represents a wrapped element
* @throws {Error} if not overridden
*/
ve.Node.prototype.isWrapped = function() {
throw 've.Node.isWrapped must be overridden in subclass';
};
/**
* Gets node length.
*
* @method
* @abstract
* @returns {Integer} Node length
* @throws {Error} if not overridden
*/
ve.Node.prototype.getLength = function() {
throw 've.Node.getLength must be overridden in subclass';
};
/**
* Gets node outer length.
*
* @method
* @abstract
* @returns {Integer} Node outer length
* @throws {Error} if not overridden
*/
ve.Node.prototype.getOuterLength = function() {
throw 've.Node.getOuterLength must be overridden in subclass';
};
/* Methods */
/**
* Gets the symbolic node type name.
*
* @method
* @returns {String} Symbolic name of element type
*/
ve.Node.prototype.getType = function() {
return this.type;
};
/**
* Gets a reference to this node's parent.
*
* @method
* @returns {ve.Node} Reference to this node's parent
*/
ve.Node.prototype.getParent = function() {
return this.parent;
};
/**
* Gets the root node in the tree this node is currently attached to.
*
* @method
* @returns {ve.Node} Root node
*/
ve.Node.prototype.getRoot = function() {
return this.root;
};
/**
* Sets the root node this node is a descendent of.
*
* This method is overridden by nodes with children.
*
* @method
* @param {ve.Node} root Node to use as root
*/
ve.Node.prototype.setRoot = function( root ) {
this.root = root;
};
/**
* Gets the document this node is a part of.
*
* @method
* @returns {ve.Document} Document this node is a part of
*/
ve.Node.prototype.getDocument = function( root ) {
return this.doc;
};
/**
* Sets the document this node is a part of.
*
* This method is overridden by nodes with children.
*
* @method
* @param {ve.Document} doc Document this node is a part of
*/
ve.Node.prototype.setDocument = function( doc ) {
this.doc = doc;
};
/**
* Attaches this node to another as a child.
*
* @method
* @param {ve.Node} parent Node to attach to
* @emits attach (parent)
*/
ve.Node.prototype.attach = function( parent ) {
this.parent = parent;
this.setRoot( parent.getRoot() );
this.setDocument( parent.getDocument() );
this.emit( 'attach', parent );
};
/**
* Detaches this node from its parent.
*
* @method
* @emits detach
*/
ve.Node.prototype.detach = function() {
this.parent = null;
this.setRoot( this );
this.setDocument();
this.emit( 'detach' );
};
/**
* Traverse tree of nodes (model or view) upstream and for each traversed node call callback function passing traversed node as a parameter.
* Callback function is called for node passed as node paramter as well.
*
* @param {ve.Node} node Node from which to start traversing
* @param {function} callback Callback method to be called for every traversed node
* @method
*/
ve.Node.traverseUpstream = function( node, callback ) {
while ( node ) {
if ( callback ( node ) === false ) {
break;
}
node = node.getParent();
}
};
/* Inheritance */
ve.extendClass( ve.Node, ve.EventEmitter );