/*
 * 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.wicket.extensions.markup.html.repeater.tree;

import java.util.Set;

import org.apache.wicket.Component;
import org.apache.wicket.core.request.handler.IPartialPageRequestHandler;
import org.apache.wicket.extensions.markup.html.repeater.tree.nested.BranchItem;
import org.apache.wicket.extensions.markup.html.repeater.tree.nested.Subtree;
import org.apache.wicket.model.IModel;
import org.apache.wicket.util.visit.IVisit;
import org.apache.wicket.util.visit.IVisitor;

/**
 * A tree with nested markup.
 * 
 * @author svenmeier
 * @param <T>
 *            the model object type
 */
public abstract class NestedTree<T> extends AbstractTree<T>
{
        private static final long serialVersionUID = 1L;

        /**
         * Construct.
         * 
         * @param id
         *            the component id
         * @param provider
         *            the provider of the tree
         */
        public NestedTree(String id, ITreeProvider<T> provider)
        {
                this(id, provider, null);
        }

        /**
         * Construct.
         * 
         * @param id
         *            the component id
         * @param provider
         *            the provider of the tree
         * @param state
         *            the expansion state
         * 
         * @see org.apache.wicket.extensions.markup.html.repeater.tree.AbstractTree.State
         */
        public NestedTree(String id, ITreeProvider<T> provider, IModel<? extends Set<T>> state)
        {
                super(id, provider, state);

                add(newSubtree("subtree", new RootsModel()));
        }

        /**
         * Create a new subtree.
         * 
         * @param id
         *            component id
         * @param model
         *            the model of the new subtree
         * @return the created component
         */
        public Component newSubtree(String id, IModel<T> model)
        {
                return new Subtree<>(id, this, model);
        }

        /**
         * Overridden to let the node output its markup id.
         * 
         * @see #updateNode(Object, IPartialPageRequestHandler)
         * @see Component#setOutputMarkupId(boolean)
         */
        @Override
        public Component newNodeComponent(String id, IModel<T> model)
        {
                Component node = super.newNodeComponent(id, model);

                node.setOutputMarkupId(true);

                return node;
        }

        /**
         * Overridden to update the corresponding {@link BranchItem} only.
         *
         * @param t
         *            node to update
         * @param target
         *            request target must not be @code null}
         */
        @Override
        public void updateBranch(T t, IPartialPageRequestHandler target)
        {
                final IModel<T> model = getProvider().model(t);
                visitChildren(BranchItem.class, new IVisitor<BranchItem<T>, Void>()
                {
                        @Override
                        public void component(BranchItem<T> branch, IVisit<Void> visit)
                        {
                                if (model.equals(branch.getModel()))
                                {
                                        // BranchItem always outputs its markupId
                                        target.add(branch);
                                        visit.stop();
                                }
                        }
                });
                model.detach();
        }

        /**
         * Overridden to update the corresponding {@link Node} only.
         *
         * @param node
         *            node to update
         * @param target
         *            request target must not be @code null}
         */
        @Override
        public void updateNode(T node, IPartialPageRequestHandler target)
        {
                final IModel<T> model = getProvider().model(node);
                visitChildren(Node.class, new IVisitor<Node<T>, Void>()
                {
                        @Override
                        public void component(Node<T> node, IVisit<Void> visit)
                        {
                                if (model.equals(node.getModel()))
                                {
                                        // nodes are configured to output their markup id, see #newNodeComponent()
                                        target.add(node);
                                        visit.stop();
                                }
                                visit.dontGoDeeper();
                        }
                });
                model.detach();
        }

        private class RootsModel implements IModel<T>
        {
                private static final long serialVersionUID = 1L;

                @Override
                public T getObject()
                {
                        return null;
                }
        }
}