/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You 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.apache.lenya.cms.site.tree2;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.apache.avalon.framework.service.ServiceException;
import org.apache.avalon.framework.service.ServiceManager;
import org.apache.lenya.cms.publication.Area;
import org.apache.lenya.cms.publication.Document;
import org.apache.lenya.cms.publication.Publication;
import org.apache.lenya.cms.repository.Node;
import org.apache.lenya.cms.repository.NodeFactory;
import org.apache.lenya.cms.repository.RepositoryException;
import org.apache.lenya.cms.repository.Session;
import org.apache.lenya.cms.site.Link;
import org.apache.lenya.cms.site.SiteException;
import org.apache.lenya.cms.site.SiteNode;
import org.apache.lenya.cms.site.SiteStructure;
import org.apache.lenya.cms.site.tree.SiteTree;

/**
 * Site tree implementation which delegates all operations to a shared site tree.
 */
public class DelegatingSiteTree implements SiteStructure, SiteTree {
    
    private SiteTreeImpl tree;
    private Area area;
    private ServiceManager manager;
    private Map links = new HashMap();
    private Map nodes = new HashMap();
    private List nodeList;
    private List topLevelNodes;
    private List preOrder;
    private String sourceUri;

    /**
     * @param manager The service manager.
     * @param area The area which this tree belongs to.
     * @param tree The tree to delegate to.
     */
    public DelegatingSiteTree(ServiceManager manager, Area area, SiteTreeImpl tree) {
        this.tree = tree;
        this.area = area;
        this.manager = manager;
    }

    public Link add(String path, Document doc) throws SiteException {
        throw new UnsupportedOperationException();
    }

    public SiteNode add(String path) throws SiteException {
        throw new UnsupportedOperationException();
    }

    public SiteNode add(String path, String followingSiblingPath) throws SiteException {
        throw new UnsupportedOperationException();
    }

    public boolean contains(String path) {
        return this.tree.contains(path);
    }

    public boolean contains(String path, String language) {
        return this.tree.contains(path, language);
    }

    public boolean containsByUuid(String uuid, String language) {
        return this.tree.containsByUuid(uuid, language);
    }

    public boolean containsInAnyLanguage(String uuid) {
        return this.tree.containsInAnyLanguage(uuid);
    }

    public String getArea() {
        return this.area.getName();
    }
    
    public Link getByUuid(String uuid, String language) throws SiteException {
        Link delegate = this.tree.getByUuid(uuid, language);
        return getLink(delegate);
    }

    protected Link getLink(Link delegate) {
        Link link = (Link) this.links.get(delegate);
        if (link == null) {
            link = new DelegatingLink(this.area.getPublication().getFactory(), getNode(delegate.getNode()),
                    delegate.getLabel(), delegate.getLanguage());
        }
        return link;
    }
    
    protected DelegatingNode getNode(SiteNode delegate) {
        DelegatingNode node = (DelegatingNode) this.nodes.get(delegate);
        if (node == null) {
            node = new DelegatingNode(this, delegate);
            this.nodes.put(delegate, node);
        }
        return node;
    }

    public SiteNode getNode(String path) throws SiteException {
        return getNode(this.tree.getNode(path));
    }

    public SiteNode[] getNodes() {
        if (this.nodeList == null) {
            SiteNode[] delegates = this.tree.getNodes();
            this.nodeList = new ArrayList();
            for (int i = 0; i < delegates.length; i++) {
                this.nodeList.add(getNode(delegates[i]));
            }
        }
        return (SiteNode[]) this.nodeList.toArray(new SiteNode[this.nodeList.size()]);
    }

    public Publication getPublication() {
        return this.area.getPublication();
    }

    public SiteNode[] getTopLevelNodes() {
        if (this.topLevelNodes == null) {
            SiteNode[] delegates = this.tree.getTopLevelNodes();
            this.topLevelNodes = new ArrayList();
            for (int i = 0; i < delegates.length; i++) {
                this.topLevelNodes.add(getNode(delegates[i]));
            }
        }
        return (SiteNode[]) this.topLevelNodes.toArray(new SiteNode[this.topLevelNodes.size()]);
    }

    public Session getSession() {
        return this.area.getPublication().getSession();
    }

    private NodeFactory nodeFactory;
    
    protected NodeFactory getNodeFactory() {
        if (this.nodeFactory == null) {
            try {
                this.nodeFactory = (NodeFactory) this.manager.lookup(NodeFactory.ROLE);
            } catch (ServiceException e) {
                throw new RuntimeException("Creating repository node failed: ", e);
            }
        }
        return this.nodeFactory;
    }

    public Node getRepositoryNode() {
        try {
            return (Node) getSession().getRepositoryItem(getNodeFactory(), getSourceUri());
        } catch (RepositoryException e) {
            throw new RuntimeException("Creating repository node failed: ", e);
        }
    }

    protected String getSourceUri() {
        if (this.sourceUri == null) {
            String baseUri = this.area.getPublication().getContentURI(this.area.getName());
            this.sourceUri = baseUri + "/sitetree.xml";
        }
        return this.sourceUri;
    }

    public void moveDown(String path) throws SiteException {
        throw new UnsupportedOperationException();
    }

    public void moveUp(String path) throws SiteException {
        throw new UnsupportedOperationException();
    }

    public SiteNode[] preOrder() {
        if (this.preOrder == null) {
            SiteNode[] delegates = this.tree.preOrder();
            this.preOrder = new ArrayList();
            for (int i = 0; i < delegates.length; i++) {
                this.preOrder.add(getNode(delegates[i]));
            }
        }
        return (SiteNode[]) this.preOrder.toArray(new SiteNode[this.preOrder.size()]);
    }

    public void save() throws RepositoryException {
        throw new UnsupportedOperationException();
    }

}