/*
 * 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 freemarker.ext.beans;

import java.lang.reflect.Array;

import freemarker.ext.util.ModelFactory;
import freemarker.template.ObjectWrapper;
import freemarker.template.TemplateCollectionModel;
import freemarker.template.TemplateModel;
import freemarker.template.TemplateModelException;
import freemarker.template.TemplateModelIterator;
import freemarker.template.TemplateSequenceModel;

A class that will wrap an arbitrary array into TemplateCollectionModel and TemplateSequenceModel interfaces. It supports element retrieval through the array[index]
syntax and can be iterated as a list.
/**
 * <p>A class that will wrap an arbitrary array into {@link TemplateCollectionModel}
 * and {@link TemplateSequenceModel} interfaces. It supports element retrieval through the <tt>array[index]</tt>
 * syntax and can be iterated as a list.
 */
public class ArrayModel
extends
    BeanModel
implements
    TemplateCollectionModel,
    TemplateSequenceModel {
    static final ModelFactory FACTORY =
        new ModelFactory()
        {
            public TemplateModel create(Object object, ObjectWrapper wrapper) {
                return new ArrayModel(object, (BeansWrapper) wrapper);
            }
        };
        
    // Cached length of the array
    private final int length;

    
Creates a new model that wraps the specified array object.
Params:
array – the array object to wrap into a model.
wrapper – the BeansWrapper associated with this model. Every model has to have an associated BeansWrapper instance. The model gains many attributes from its wrapper, including the caching behavior, method exposure level, method-over-item shadowing policy etc.
Throws:
IllegalArgumentException – if the passed object is not a Java array./**
     * Creates a new model that wraps the specified array object.
     * @param array the array object to wrap into a model.
     * @param wrapper the {@link BeansWrapper} associated with this model.
     * Every model has to have an associated {@link BeansWrapper} instance. The
     * model gains many attributes from its wrapper, including the caching 
     * behavior, method exposure level, method-over-item shadowing policy etc.
     * @throws IllegalArgumentException if the passed object is not a Java array.
     */
    public ArrayModel(Object array, BeansWrapper wrapper) {
        super(array, wrapper);
        Class clazz = array.getClass();
        if (!clazz.isArray())
            throw new IllegalArgumentException("Object is not an array, it's " + array.getClass().getName());
        length = Array.getLength(array);
    }


    public TemplateModelIterator iterator() {
        return new Iterator();
    }

    public TemplateModel get(int index)
    throws TemplateModelException {
        try {
            return wrap(Array.get(object, index));
        } catch (IndexOutOfBoundsException e) {
            return null; 
//            throw new TemplateModelException("Index out of bounds: " + index);
        }
    }

    private class Iterator
    implements 
        TemplateSequenceModel,
        TemplateModelIterator {
        private int position = 0;

        public boolean hasNext() {
            return position < length;
        }

        public TemplateModel get(int index)
        throws TemplateModelException {
            return ArrayModel.this.get(index);
        }

        public TemplateModel next()
        throws TemplateModelException {
            return position < length ? get(position++) : null;
        }

        public int size() {
            return ArrayModel.this.size();
        }
    }

    @Override
    public int size() {
        return length;
    }

    @Override
    public boolean isEmpty() {
        return length == 0;
    }
}