/*
 * ====================================================================
 *
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 1999-2001 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "The Jakarta Project", "Struts", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache"
 *    nor may "Apache" appear in their names without prior written
 *    permission of the Apache Group.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 */

package org.apache.struts.taglib.html;

import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.PageContext;
import javax.servlet.jsp.tagext.TagSupport;
import org.apache.struts.util.IteratorAdapter;
import org.apache.struts.util.MessageResources;
import org.apache.struts.util.PropertyUtils;
import org.apache.struts.util.ResponseUtils;
import java.util.Arrays;
import java.util.Collection;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.Map;


/**
 * Tag for creating multiple &lt;select&gt; options from a collection.  The
 * associated values displayed to the user may optionally be specified by a
 * second collection, or will be the same as the values themselves.  Each
 * collection may be an array of objects, a Collection, an Enumeration,
 * an Iterator, or a Map.
 * <b>NOTE</b> - This tag requires a Java2 (JDK 1.2 or later) platform.
 *
 * @author Florent Carpentier
 * @author Craig McClanahan
 */

public class OptionsTag extends TagSupport {

    /**
     * The message resources for this package.
     */
    protected static MessageResources messages =
     MessageResources.getMessageResources(Constants.Package + ".LocalStrings");

    /**
     * The name of the collection containing beans that have properties to
     * provide both the values and the labels (identified by the
     * <code>property</code> and <code>labelProperty</code> attributes).
     */
    protected String collection = null;


	public String getCollection()
	{
		return (this.collection);
	}


	public void setCollection(String collection)
	{
		this.collection = collection;
	}


    /**
     * The name of the bean containing the labels collection.
     */
    protected String labelName = null;


	public String getLabelName()
	{
		return labelName;
	}


	public void setLabelName(String labelName)
	{
		this.labelName = labelName;
	}

    /**
     * The bean property containing the labels collection.
     */
    protected String labelProperty = null;


	public String getLabelProperty()
	{
		return labelProperty;
	}


	public void setLabelProperty(String labelProperty)
	{
		this.labelProperty = labelProperty;
	}

    /**
     * The name of the bean containing the values collection.
     */
    protected String name=null;


	public String getName()
	{
		return name;
	}


	public void setName(String name)
	{
		this.name = name;
	}


    /**
     * The name of the property to use to build the values collection.
     */
    protected String property=null;


	public String getProperty()
	{
		return property;
	}


	public void setProperty(String property)
	{
		this.property = property;
	}


	/**
	 * Process the start of this tag.
	 *
	 * @exception JspException if a JSP exception has occurred
	 */
	
	public int doStartTag() throws JspException
	{
		return SKIP_BODY;
	}


	/**
	 * Process the end of this tag.
	 *
	 * @exception JspException if a JSP exception has occurred
	 */
	public int doEndTag() throws JspException
	{
	
		// Acquire the select tag we are associated with
		SelectTag selectTag = (SelectTag) pageContext.getAttribute(Constants.SELECT_KEY);
		if (selectTag == null)
			throw new JspException(messages.getMessage("optionsTag.select"));
		StringBuffer sb = new StringBuffer();
	
		// If a collection was specified, use that mode to render options
		if (collection != null)
		{
			Iterator collIterator = null;
			Object colBean = pageContext.findAttribute(collection);
			if (colBean == null)
			{
				collIterator = getIterator(name, collection);
			}
			else
			{
				collIterator = getIterator(collection, null);
			}
			while (collIterator.hasNext())
			{
	
				Object bean = collIterator.next();
				Object value = null;
				Object label = null;
				;
	
				try
				{
					value = PropertyUtils.getProperty(bean, property);
					if (value == null)
						value = "";
				}
				catch (IllegalAccessException e)
				{
					throw new JspException(messages.getMessage("getter.access", property, collection));
				}
				catch (InvocationTargetException e)
				{
					Throwable t = e.getTargetException();
					throw new JspException(messages.getMessage("getter.result", property, t.toString()));
				}
				catch (NoSuchMethodException e)
				{
					throw new JspException(messages.getMessage("getter.method", property, collection));
				}
	
				try
				{
					if (labelProperty != null)
						label = PropertyUtils.getProperty(bean, labelProperty);
					else
						label = value;
					if (label == null)
						label = "";
				}
				catch (IllegalAccessException e)
				{
					throw new JspException(messages.getMessage("getter.access", labelProperty, collection));
				}
				catch (InvocationTargetException e)
				{
					Throwable t = e.getTargetException();
					throw new JspException(messages.getMessage("getter.result", labelProperty, t.toString()));
				}
				catch (NoSuchMethodException e)
				{
					throw new JspException(messages.getMessage("getter.method", labelProperty, collection));
				}
	
				String stringValue = value.toString();
				addOption(sb, stringValue, label.toString(), selectTag.isMatched(stringValue));
	
			}
	
		}
	
		// Otherwise, use the separate iterators mode to render options
		else
		{
	
			// Construct iterators for the values and labels collections
			Iterator valuesIterator = getIterator(name, property);
			Iterator labelsIterator = null;
			if ((labelName == null) && (labelProperty == null))
				labelsIterator = getIterator(name, property); // Same coll.
			else
				labelsIterator = getIterator(labelName, labelProperty);
	
			// Render the options tags for each element of the values coll.
			while (valuesIterator.hasNext())
			{
				String value = valuesIterator.next().toString();
				String label = value;
				if (labelsIterator.hasNext())
					label = labelsIterator.next().toString();
				addOption(sb, value, label, selectTag.isMatched(value));
			}
		}
	
		// Render this element to our writer
		ResponseUtils.write(pageContext, sb.toString());
	
		// Evaluate the remainder of this page
		return EVAL_PAGE;
	
	}


	/**
	 * Release any acquired resources.
	 */
	public void release()
	{
	
		super.release();
		collection = null;
		labelName = null;
		labelProperty = null;
		name = null;
		property = null;
	
	}


	// ------------------------------------------------------ Protected Methods
	
	/**
	 * Add an option element to the specified StringBuffer based on the
	 * specified parameters.
	 *
	 * @param sb StringBuffer accumulating our results
	 * @param value Value to be returned to the server for this option
	 * @param label Value to be shown to the user for this option
	 * @param matched Should this value be marked as selected?
	 */
	protected void addOption(StringBuffer sb, String value, String label, boolean matched)
	{
	
		sb.append("<option value=\"");
		sb.append(value);
		sb.append("\"");
		if (matched)
			sb.append(" selected=\"selected\"");
		sb.append(">");
		sb.append(ResponseUtils.filter(label));
		sb.append("</option>\r\n");
	
	}


	/**
	 * Return an iterator for the option labels or values, based on our
	 * configured properties.
	 *
	 * @param name Name of the bean attribute (if any)
	 * @param property Name of the bean property (if any)
	 *
	 * @exception JspException if an error occurs
	 */
	protected Iterator getIterator(String name, String property) throws JspException
	{
	
		// Identify the bean containing our collection
		String beanName = name;
		if (beanName == null)
			beanName = Constants.BEAN_KEY;
		Object bean = pageContext.findAttribute(beanName);
		if (bean == null)
			throw new JspException(messages.getMessage("getter.bean", beanName));
	
		// Identify the collection itself
		Object collection = bean;
		if (property != null)
		{
			try
			{
				collection = PropertyUtils.getProperty(bean, property);
			}
			catch (IllegalAccessException e)
			{
				throw new JspException(messages.getMessage("getter.access", property, name));
			}
			catch (InvocationTargetException e)
			{
				Throwable t = e.getTargetException();
				throw new JspException(messages.getMessage("getter.result", property, t.toString()));
			}
			catch (NoSuchMethodException e)
			{
				throw new JspException(messages.getMessage("getter.method", property, name));
			}
		}
	
		// Construct and return an appropriate iterator
		if (collection.getClass().isArray())
			collection = Arrays.asList((Object[]) collection);
		if (collection instanceof Collection)
			return (((Collection) collection).iterator());
		else if (collection instanceof Iterator)
			return ((Iterator) collection);
		else if (collection instanceof Map)
			return (((Map) collection).entrySet().iterator());
		else if (collection instanceof Enumeration)
			return (new IteratorAdapter((Enumeration) collection));
		else
			throw new JspException(messages.getMessage("optionsTag.iterator", collection.toString()));
	
	}

}