/*
 * $Header: /home/cvspublic/jakarta-struts/src/share/org/apache/struts/taglib/html/SelectTag.java,v 1.5 2001/06/10 03:53:31 craigmcc Exp $
 * $Revision: 1.5 $
 * $Date: 2001/06/10 03:53:31 $
 *
 * ====================================================================
 *
 * 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.http.HttpServletResponse;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.PageContext;
import org.apache.struts.util.BeanUtils;
import org.apache.struts.util.MessageResources;
import org.apache.struts.util.RequestUtils;
import org.apache.struts.util.ResponseUtils;


/**
 * Custom tag that represents an HTML select element, associated with a
 * bean property specified by our attributes.  This tag must be nested
 * inside a form tag.
 *
 * @author Craig R. McClanahan
 * @version $Revision: 1.5 $ $Date: 2001/06/10 03:53:31 $
 */

public class SelectTag extends BaseHandlerTag {


    // ----------------------------------------------------- Instance Variables


    /**
     * The actual values we will match against, calculated in doStartTag().
     */
    protected String match[] = null;


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


    /**
     * Should multiple selections be allowed?  Any non-null value will
     * trigger rendering this.
     */
    protected String multiple = null;


	public String getMultiple()
	{
		return (this.multiple);
	}


	public void setMultiple(String multiple)
	{
		this.multiple = multiple;
	}


    /**
     * The name of the bean containing our underlying property.
     */
    protected String name = Constants.BEAN_KEY;


	public String getName()
	{
		return (this.name);
	}


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


    /**
     * The property name we are associated with.
     */
    protected String property = null;


    /**
     * The saved body content of this tag.
     */
    protected String saveBody = null;


    /**
     * How many available options should be displayed when this element
     * is rendered?
     */
    protected String size = null;


	public String getSize()
	{
		return (this.size);
	}


	public void setSize(String size)
	{
		this.size = size;
	}


    /**
     * The value to compare with for marking an option selected.
     */
    protected String value = null;


	// ------------------------------------------------------------- Properties
	
	/**
	 * Does the specified value match one of those we are looking for?
	 *
	 * @param value Value to be compared
	 */
	public boolean isMatched(String value)
	{
	
		if ((match == null) || (value == null))
			return (false);
		for (int i = 0; i < match.length; i++)
		{
			if (value.equals(match[i]))
				return (true);
		}
		return (false);
	
	}


	/**
	 * Return the property name.
	 */
	public String getProperty()
	{
	
		return (this.property);
	
	}


	/**
	 * Set the property name.
	 *
	 * @param property The new property name
	 */
	public void setProperty(String property)
	{
	
		this.property = property;
	
	}


	/**
	 * Return the comparison value.
	 */
	public String getValue()
	{
	
		return (this.value);
	
	}


	/**
	 * Set the comparison value.
	 *
	 * @param value The new comparison value
	 */
	public void setValue(String value)
	{
	
		this.value = value;
	
	}


	// --------------------------------------------------------- Public Methods
	
	/**
	 * Render the beginning of this form.
	 *
	 * @exception JspException if a JSP exception has occurred
	 */
	public int doStartTag() throws JspException
	{
	
		// Create an appropriate "form" element based on our parameters
		StringBuffer results = new StringBuffer("<select");
		results.append(" name=\"");
		results.append(property);
		results.append("\"");
		if (accesskey != null)
		{
			results.append(" accesskey=\"");
			results.append(accesskey);
			results.append("\"");
		}
		if (multiple != null)
		{
			results.append(" multiple=\"multiple\"");
		}
		if (size != null)
		{
			results.append(" size=\"");
			results.append(size);
			results.append("\"");
		}
		if (tabindex != null)
		{
			results.append(" tabindex=\"");
			results.append(tabindex);
			results.append("\"");
		}
		results.append(prepareEventHandlers());
		results.append(prepareStyles());
		results.append(">");
	
		// Print this field to our output writer
		ResponseUtils.write(pageContext, results.toString());
	
		// Store this tag itself as a page attribute
		pageContext.setAttribute(Constants.SELECT_KEY, this);
	
		// Calculate the match values we will actually be using
		if (value != null)
		{
			match = new String[1];
			match[0] = value;
		}
		else
		{
			generateMatched();
		}
	
		// Continue processing this page
		return (EVAL_BODY_TAG);
	
	}


	/**
	 * Save any body content of this tag, which will generally be the
	 * option(s) representing the values displayed to the user.
	 *
	 * @exception JspException if a JSP exception has occurred
	 */
	public int doAfterBody() throws JspException
	{
	
		if (bodyContent != null)
		{
			String value = bodyContent.getString();
			if (value == null)
				value = "";
			saveBody = value.trim();
		}
		return (SKIP_BODY);
	
	}


	/**
	 * Render the end of this form.
	 *
	 * @exception JspException if a JSP exception has occurred
	 */
	public int doEndTag() throws JspException
	{
	
		// Remove the page scope attributes we created
		pageContext.removeAttribute(Constants.SELECT_KEY);
	
		// Render a tag representing the end of our current form
		StringBuffer results = new StringBuffer();
		if (saveBody != null)
			results.append(saveBody);
		results.append("</select>");
	
		// Print this value to our output writer
		ResponseUtils.write(pageContext, results.toString());
	
		// Continue processing this page
		return (EVAL_PAGE);
	
	}


	/**
	 * Release any acquired resources.
	 */
	public void release()
	{
	
		super.release();
		match = null;
		multiple = null;
		name = Constants.BEAN_KEY;
		property = null;
		saveBody = null;
		size = null;
		value = null;
	
	}


	// --------------------------------------------------------- Public Methods
	
	/**
	 * Render the beginning of this form.
	 *
	 * @exception JspException if a JSP exception has occurred
	 */
	public void generateMatched() throws JspException
	{
		Object bean = pageContext.findAttribute(name);
		if (bean == null)
		{
			JspException e = new JspException(messages.getMessage("getter.bean", name));
			RequestUtils.saveException(pageContext, e);
			throw e;
		}
		try
		{
			match = BeanUtils.getArrayProperty(bean, property);
			if (match == null)
				match = new String[0];
		}
		catch (IllegalAccessException e)
		{
			RequestUtils.saveException(pageContext, e);
			throw new JspException(messages.getMessage("getter.access", property, name));
		}
		catch (InvocationTargetException e)
		{
			Throwable t = e.getTargetException();
			RequestUtils.saveException(pageContext, t);
			throw new JspException(messages.getMessage("getter.result", property, t.toString()));
		}
		catch (NoSuchMethodException e)
		{
			RequestUtils.saveException(pageContext, e);
			throw new JspException(messages.getMessage("getter.method", property, name));
		}
	}
}