/* ================================================================

 * Cewolf : Chart enabling Web Objects Framework

 * ================================================================

 *

 * Project Info:  http://cewolf.sourceforge.net

 * Project Lead:  Guido Laures (guido@laures.de);

 *

 * (C) Copyright 2002, by Guido Laures

 *

 * This library is free software; you can redistribute it and/or modify it under the terms

 * of the GNU Lesser General Public License as published by the Free Software Foundation;

 * either version 2.1 of

 * the License, or (at your option) any later version.

 *

 * This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;

 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

 * See the GNU Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public License along with this

 * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,

 * Boston, MA 02111-1307, USA.

 */

package de.laures.cewolf.taglib.tags;

import java.io.IOException;

import javax.servlet.jsp.JspException;

import de.laures.cewolf.CewolfException;

import de.laures.cewolf.ChartHolder;

import de.laures.cewolf.ChartImage;

import de.laures.cewolf.Configuration;

import de.laures.cewolf.Storage;

import de.laures.cewolf.WebConstants;

import de.laures.cewolf.taglib.ChartImageDefinition;

import de.laures.cewolf.taglib.TaglibConstants;

import de.laures.cewolf.taglib.html.HTMLImgTag;

import de.laures.cewolf.taglib.util.PageUtils;

/**

 * Tag <legend> which can be used to render a chart's legend

 * separately somewhere in the page.

 * @author  Guido Laures

 */

public class LegendTag extends HTMLImgTag implements CewolfRootTag, TaglibConstants, WebConstants {

    private static final String DEFAULT_MIME_TYPE = MIME_PNG;

    private static final int DEFAULT_TIMEOUT = 300;

    private int timeout = DEFAULT_TIMEOUT;

    private transient String sessionKey;

    private transient String renderer;

    private String mimeType = DEFAULT_MIME_TYPE;

    public int doStartTag() throws JspException {

        ChartHolder cd = PageUtils.getChartHolder(getChartId(), pageContext);

        ChartImage cid = new ChartImageDefinition(cd, width, height, ChartImage.IMG_TYPE_LEGEND, mimeType,timeout);

        Storage storage = Configuration.getInstance(pageContext.getServletContext()).getStorage();

        try {

        	this.sessionKey = storage.storeChartImage(cid, pageContext);

        } catch(CewolfException cwex){

        	log.error(cwex);

        	throw new JspException(cwex.getMessage());

        }

        return SKIP_BODY;

    }

    public int doEndTag() throws JspException {

		super.doStartTag();

		final StringBuffer buffer = new StringBuffer(" src=\"");

		buffer.append(getImgURL());

		buffer.append("\"");

		try {

			pageContext.getOut().write(buffer.toString());

		} catch (IOException ioex) {

			reset();

			log.error(ioex);

			throw new JspException(ioex.getMessage());

		}

		return super.doEndTag();

    }

	/**

	* To enable further server side scriptings on JSP output the session ID is always

	* encoded into the image URL even if cookies are enabled on the client side.

	*/

	protected String getImgURL() {

		return ChartImgTag.buildImgURL(renderer, pageContext, sessionKey, width, height, mimeType, forceSessionId,removeAfterRender);

	}

    protected void reset() {

        // as of a weird JSP compiler in resin

        // a reused tag's attribute is only set if 

        // it changes. So width an height may not

        // be unset to ensure correct values.

        int lHeight = this.height;

        int lWidth = this.width;

        int lTimeout = this.timeout;

        super.reset();

        this.height = lHeight;

        this.width = lWidth;

        this.timeout = lTimeout;

    }

    public String getChartId() {

        return getId();

    }

    public void setRenderer(String rend) {

        this.renderer = rend;

    }

    /**

     * Sets the mimeType.

     * @param mimeType The mimeType to set

     */

    public void setMime(String mimeType) {

        this.mimeType = mimeType;

    }

    /**

     * @return Returns the timeout.

     */

    public int getTimeout()

    {

      return timeout;

    }

    /**

     * @param timeout The timeout to set.

     */

    public void setTimeout( int timeout )

    {

      this.timeout = timeout;

    }

}