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

/**
 * DataModel link annotation.
 *
 * Represents `<a>` tags that don't have a specific type.
 *
 * @class
 * @extends ve.dm.Annotation
 * @constructor
 * @param {HTMLElement|Object} element
 */
ve.dm.LinkAnnotation = function VeDmLinkAnnotation( element ) {
	// Parent constructor
	ve.dm.Annotation.call( this, element );
};

/* Inheritance */

ve.inheritClass( ve.dm.LinkAnnotation, ve.dm.Annotation );

/* Static Properties */

/**
 * @static
 * @property static.name
 * @inheritdoc
 */
ve.dm.LinkAnnotation.static.name = 'link';

/**
 * @static
 * @property static.matchTagNames
 * @inheritdoc
 */
ve.dm.LinkAnnotation.static.matchTagNames = ['a'];

/* Methods */

/**
 * Get annotation data, especially the href of the link.
 *
 * @method
 * @param {HTMLElement} element
 * @returns {Object} Annotation data, containing href property
 */
ve.dm.LinkAnnotation.prototype.getAnnotationData = function( element ) {
	return { 'href': element.getAttribute( 'href' ) };
};

/**
 * Convert to an object with HTML element information.
 *
 * @method
 * @returns {Object} HTML element information, including tag and attributes properties
 */
ve.dm.LinkAnnotation.prototype.toHTML = function () {
	var parentResult = ve.dm.Annotation.prototype.toHTML.call( this );
	parentResult.tag = 'a';
	parentResult.attributes.href = this.data.href;
	return parentResult;
};

/**
 * Get a hash of the link annotation.
 *
 * This extends the basic annotation hash by adding htmlAttributes.rel
 * if it present.
 *
 * This is a custom hash function for ve#getHash.
 *
 * @method
 * @returns {string} Hash string
 */
ve.dm.LinkAnnotation.prototype.getHash = function () {
	var keys = [ 'name', 'data' ], obj = {}, i;
	for ( i = 0; i < keys.length; i++ ) {
		if ( this[keys[i]] !== undefined ) {
			obj[keys[i]] = this[keys[i]];
		}
	}
	if ( this.htmlAttributes && this.htmlAttributes.rel ) {
		obj.htmlAttributes = {};
		obj.htmlAttributes.rel = this.htmlAttributes.rel;
	}
	return ve.getHash( obj );
};

/* Registration */

ve.dm.modelRegistry.register( ve.dm.LinkAnnotation );