/*
 * Copyright 2015 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.springframework.social.config.xml;

import java.util.HashMap;
import java.util.Map;

import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.config.BeanDefinitionHolder;
import org.springframework.beans.factory.xml.BeanDefinitionParser;
import org.springframework.beans.factory.xml.NamespaceHandler;
import org.springframework.beans.factory.xml.ParserContext;
import org.w3c.dom.Element;
import org.w3c.dom.Node;

/**
 * {@link NamespaceHandler} for Spring Social
 * 
 * @author Craig Walls
 */
public class SocialNamespaceHandler implements NamespaceHandler {

    private final Map<String, BeanDefinitionParser> parsers = new HashMap<String, BeanDefinitionParser>();

	public void init() {
		loadParsers();
	}

	public BeanDefinition parse(Element element, ParserContext parserContext) {
		String name = parserContext.getDelegate().getLocalName(element);
        BeanDefinitionParser parser = parsers.get(name);
        if (parser == null) {
            loadParsers();
        }
        
        if(parser == null) {
        	// if missing classes from other modules (Facebook, Web, etc) report that separately    
        	// their parsers should be supplied by the individual modules
        	reportUnsupportedNodeType(name, parserContext, element);
        	return null;
        }
        
        return parser.parse(element, parserContext);
	}

	public BeanDefinitionHolder decorate(Node source, BeanDefinitionHolder definition, ParserContext parserContext) {
		return definition;
	}
	
    private void reportUnsupportedNodeType(String name, ParserContext parserContext, Node node) {
        parserContext.getReaderContext().fatal("Social namespace does not support decoration of " +
                (node instanceof Element ? "element" : "attribute") + " [" + name + "]", node);
    }

	private void loadParsers() {
		parsers.put("jdbc-connection-repository", new JdbcConnectionRepositoryBeanDefinitionParser());
		parsers.put("in-memory-connection-repository", new InMemoryConnectionRepositoryBeanDefinitionParser());
	}

}