/* Copyright (c) 2006-2008 MetaCarta, Inc., published under the Clear BSD
 * license.  See http://svn.openlayers.org/trunk/openlayers/license.txt for the
 * full text of the license. */

/**
 * @requires OpenLayers/Format/XML.js
 */

/**
 * Class: OpenLayers.Format.WMCC.v1
 * Superclass for WMC version 1 parsers.
 *
 * Inherits from:
 *  - <OpenLayers.Format.XML>
 */
OpenLayers.Format.WMCC.v1 = OpenLayers.Class(OpenLayers.Format.XML, {
    
    /**
     * Property: namespaces
     * {Object} Mapping of namespace aliases to namespace URIs.
     */
    namespaces: {
        ol: "http://openlayers.org/context",
        wmcc: "http://www.opengis.net/context",
		sld: "http://www.opengis.net/sld",
        xlink: "http://www.w3.org/1999/xlink",
        xsi: "http://www.w3.org/2001/XMLSchema-instance"
    },
    
    /**
     * Property: schemaLocation
     * {String} Schema location for a particular minor version.
     */
    schemaLocation: "",

    /**
     * Method: getNamespacePrefix
     * Get the namespace prefix for a given uri from the <namespaces> object.
     *
     * Returns:
     * {String} A namespace prefix or null if none found.
     */
    getNamespacePrefix: function(uri) {
        var prefix = null;
        if(uri == null) {
            prefix = this.namespaces[this.defaultPrefix];
        } else {
            for(prefix in this.namespaces) {
                if(this.namespaces[prefix] == uri) {
                    break;
                }
            }
        }
        return prefix;
    },
    
    /**
     * Property: defaultPrefix
     */
    defaultPrefix: "wmcc",

    /**
     * Property: rootPrefix
     * {String} Prefix on the root node that maps to the context namespace URI.
     */
    rootPrefix: null,
    
    /**
     * Property: defaultStyleName
     * {String} Style name used if layer has no style param.  Default is "".
     */
    defaultStyleName: "",
    
    /**
     * Property: defaultStyleTitle
     * {String} Default style title.  Default is "Default".
     */
    defaultStyleTitle: "Default",
    
    /**
     * Constructor: OpenLayers.Format.WMCC.v1
     * Instances of this class are not created directly.  Use the
     *     <OpenLayers.Format.WMCC> constructor instead.
     *
     * Parameters:
     * options - {Object} An optional object whose properties will be set on
     *     this instance.
     */
    initialize: function(options) {
        OpenLayers.Format.XML.prototype.initialize.apply(this, [options]);
    },

    /**
     * Method: read
     * Read capabilities data from a string, and return a list of layers. 
     * 
     * Parameters: 
     * data - {String} or {DOMElement} data to read/parse.
     *
     * Returns:
     * {Array} List of named layers.
     */
    read: function(data) {
        if(typeof data == "string") {
            data = OpenLayers.Format.XML.prototype.read.apply(this, [data]);
        }
        var root = data.documentElement;
        this.rootPrefix = root.prefix;
        var context = {
            version: root.getAttribute("version"),
			references: []
        };

        this.runChildNodes(context, root);
        return context;
    },
    
    /**
     * Method: runChildNodes
     */
    runChildNodes: function(obj, node) {
        var children = node.childNodes;
        var childNode, processor, prefix, local;
        for(var i=0, len=children.length; i<len; ++i) {
            childNode = children[i];
            if(childNode.nodeType == 1) {
                prefix = this.getNamespacePrefix(childNode.namespaceURI);
                local = childNode.nodeName.split(":").pop();
                processor = this["read_" + prefix + "_" + local];
                if(processor) {
                    processor.apply(this, [obj, childNode]);
                }
            }
        }
    },


	/**
     * Method: read_wmcc_ViewContextReference
     */
    read_wmcc_ViewContextReference: function(context, node) {
		var reference = {};
        this.runChildNodes(reference, node);
		context.references.push(reference);
    },


	/**
     * Method: read_wmcc_Title
     */
    read_wmcc_Title: function(reference, node) {
        reference.title = this.getChildValue(node);
    },

	
	/**
     * Method: read_wmcc_ContextURL
     */
    read_wmcc_ContextURL: function(reference, node) {
        var onlineResourceNode = node.getElementsByTagName("OnlineResource");		
		reference.url = this.getAttributeNS(onlineResourceNode[0], this.namespaces.xlink, "href");
    },
	
	
	CLASS_NAME: "OpenLayers.Format.WMCC.v1" 

});