/*!
 * VisualEditor ContentEditable MWExtensionNode class.
 *
 * @copyright 2011-2013 VisualEditor Team and others; see AUTHORS.txt
 * @license The MIT License (MIT); see LICENSE.txt
 */

/*global mw */

/**
 * ContentEditable MediaWiki extension node.
 *
 * Configuration options for .update():
 * - 'extsrc': override the contents of the tag (string)
 * - 'attrs': override the attributes of the tag (object)
 *
 * @class
 * @abstract
 * @extends ve.ce.LeafNode
 * @mixins ve.ce.FocusableNode
 * @mixins ve.ce.ProtectedNode
 * @mixins ve.ce.RelocatableNode
 * @mixins ve.ce.GeneratedContentNode
 *
 * @constructor
 * @param {ve.dm.MWExtensionNode} model Model to observe
 * @param {Object} [config] Configuration options
 */
ve.ce.MWExtensionNode = function VeCeMWExtensionNode( model, config ) {
	// Parent constructor
	ve.ce.LeafNode.call( this, model, config );

	// Mixin constructors
	ve.ce.FocusableNode.call( this );
	ve.ce.ProtectedNode.call( this );
	ve.ce.RelocatableNode.call( this );
	ve.ce.GeneratedContentNode.call( this );

	// DOM changes
	this.$element.addClass( 've-ce-mwExtensionNode' );
};

/* Inheritance */

OO.inheritClass( ve.ce.MWExtensionNode, ve.ce.LeafNode );

OO.mixinClass( ve.ce.MWExtensionNode, ve.ce.FocusableNode );
OO.mixinClass( ve.ce.MWExtensionNode, ve.ce.ProtectedNode );
OO.mixinClass( ve.ce.MWExtensionNode, ve.ce.RelocatableNode );
OO.mixinClass( ve.ce.MWExtensionNode, ve.ce.GeneratedContentNode );

/* Methods */

/** */
ve.ce.MWExtensionNode.prototype.generateContents = function ( config ) {
	var xhr,
		deferred = $.Deferred(),
		mwData = this.getModel().getAttribute( 'mw' ),
		extsrc = config && config.extsrc !== undefined ? config.extsrc : mwData.body.extsrc,
		attrs = config && config.attrs || mwData.attrs,
		xmlDoc = ( new DOMParser() ).parseFromString( '<' + this.getModel().getExtensionName() + '/>', 'text/xml' ),
		wikitext = ( new XMLSerializer() ).serializeToString(
			$( xmlDoc.documentElement ).attr( attrs ).text( extsrc )[0]
		);

	xhr = $.ajax( {
		'url': mw.util.wikiScript( 'api' ),
		'data': {
			'action': 'visualeditor',
			'paction': 'parsefragment',
			'page': mw.config.get( 'wgRelevantPageName' ),
			'wikitext': wikitext,
			'format': 'json'
		},
		'dataType': 'json',
		'type': 'POST',
		// Wait up to 100 seconds before giving up
		'timeout': 100000,
		'cache': 'false'
	} )
		.done( ve.bind( this.onParseSuccess, this, deferred ) )
		.fail( ve.bind( this.onParseError, this, deferred ) );

	return deferred.promise( { abort: xhr.abort } );
};

/**
 * Handle a successful response from the parser for the wikitext fragment.
 *
 * @param {jQuery.Deferred} deferred The Deferred object created by generateContents
 * @param {Object} response Response data
 */
ve.ce.MWExtensionNode.prototype.onParseSuccess = function ( deferred, response ) {
	var data = response.visualeditor, contentNodes = this.$( data.content ).get();
	deferred.resolve( contentNodes );
};

/** */
ve.ce.MWExtensionNode.prototype.afterRender = function () {
	// Rerender after images load
	// TODO: ignore shields, and count multiple images
	this.$element.find( 'img' ).on( 'load', ve.bind( function () {
		this.emit( 'rerender' );
	}, this ) );
};

/**
 * Handle an unsuccessful response from the parser for the wikitext fragment.
 *
 * @param {jQuery.Deferred} deferred The promise object created by generateContents
 * @param {Object} response Response data
 */
ve.ce.MWExtensionNode.prototype.onParseError = function ( deferred ) {
	deferred.reject();
};