/*
    * Copyright 2004 Jeff Johnston
    *
    * Licensed 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.extremecomponents.table.model;
  
  import java.net.URLEncoder;
  import java.util.Enumeration;
  import java.util.HashMap;
  import java.util.Iterator;
  import java.util.Map;
  import java.util.Set;
  
  import javax.servlet.jsp.PageContext;
  
  import org.apache.commons.lang.StringUtils;
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.extremecomponents.table.bean.Table;
  
  
  /***
   *
   * @author jeff johnston
   */
  public class ParameterRegistry
  {
  	private static Log logger = LogFactory.getLog(ParameterRegistry.class);
  	
  	public final static String PAGE = "page_";
  	public final static String SORT = "sort_";
  	public final static String FILTER = "filter_";
  	public final static String EXPORT = "export_";
  	public final static String APPEND = "append_";
  	public final static String OPEN = "open_";
  	private TableModel model;
  	private Map parameters = new HashMap();
  
  	public ParameterRegistry(TableModel model)
  	{
  		this.model = model;
  	}
  
  	public void init(PageContext pageContext)
  	{
  		Enumeration enumeration = pageContext.getRequest().getParameterNames();
  
  		while (enumeration.hasMoreElements())
  		{
  			String name = (String) enumeration.nextElement();
  			String value = pageContext.getRequest().getParameter(name);
  
  			if (StringUtils.isEmpty(value))
  			{
  				continue; //whats the point
  			}
  
  			if (name.startsWith(model.getTableKey() + PAGE) || 
  				name.startsWith(model.getTableKey() + SORT) || 
  				name.startsWith(model.getTableKey() + FILTER) || 
  				name.startsWith(model.getTableKey() + EXPORT) ||
  				name.startsWith(model.getTableKey() + OPEN))
  			{
  				parameters.put(name, value);
  			}
  			else
  			{
  				if (model.getProperties().getProperty(TableProperties.AUTO_INCLUDE_PARAMETERS).equals("true")) //accept all parameters
  				{
  					if (!name.equals(Table.EXTREME_TABLE)) //filter out this variable
  					{
  						parameters.put(name, value);
  					}
  				}
  			}
  		}
  	}
  
  	/***
  	 * Add additional parameters that need to be passed around
  	 */
  	public void addParameter(String name, String value)
  	{
  		parameters.put(name, value);
  	}
  
  	/***
  	 * Get the parameter
 	 */
 	public String getParameter(String parameter)
 	{
 		return (String) parameters.get(model.getTableKey() + parameter);
 	}
 
 	/***
 	 * Get a map of specific parameters
 	 */
 	public Map getParameters(String parameter)
 	{
 		Map subset = new HashMap();
 
 		Set set = parameters.keySet();
 
 		for (Iterator iter = set.iterator(); iter.hasNext();)
 		{
 			String name = (String) iter.next();
 
 			if (name.startsWith(model.getTableKey() + parameter))
 			{
 				String value = (String) parameters.get(name);
 				subset.put(name, value);
 			}
 		}
 
 		return subset;
 	}
 
 	/***
 	 * Get a map of specific parameters
 	 */
 	public Map clearParameters(String parameter)
 	{
 		Map subset = new HashMap();
 
 		Set set = parameters.keySet();
 
 		for (Iterator iter = set.iterator(); iter.hasNext();)
 		{
 			String name = (String) iter.next();
 
 			if (name.startsWith(model.getTableKey() + parameter))
 			{
 				iter.remove();
 			}
 		}
 
 		return subset;
 	}
 
 	/***
 	 * Take the parameters and format into hidden fields
 	 */
 	public String getHiddenFields(String parameter)
 	{
 		StringBuffer sb = new StringBuffer();
 
 		Set keys = parameters.keySet();
 
 		for (Iterator iter = keys.iterator(); iter.hasNext();)
 		{
 			String name = (String) iter.next();
 
 			if (((parameter == null) && !name.startsWith(model.getTableKey())) || (name.startsWith(model.getTableKey() + parameter)))
 			{
 				String value = (String) parameters.get(name);
 				sb.append("\n\t<input type=\"hidden\" name=\"" + name + "\" value=\"" + value + "\">\n");
 			}
 		}
 
 		return sb.toString();
 	}
 
 	/***
 	 * Get a URI formated parameter string. Will look like &key=value
 	 */
 	public String getParameterString(String parameter)
 	{
 		StringBuffer sb = new StringBuffer();
 
 		Set keys = parameters.keySet();
 
 		for (Iterator iter = keys.iterator(); iter.hasNext();)
 		{
 			String name = (String) iter.next();
 
 			if (((parameter == null) && !name.startsWith(model.getTableKey())) || (name.startsWith(model.getTableKey() + parameter)))
 			{
 				String value = (String) parameters.get(name);
 				value = URLEncoder.encode(value);
 				sb.append("&" + name + "=" + value);
 			}
 		}
 
 		return sb.toString();
 	}
 
 	/***
 	 * Get parameter datum.
 	 */
 	public String getURLParameterString(boolean filter, boolean sort, boolean page)
 	{
 		StringBuffer sb = new StringBuffer();
 
 		if (filter)
 		{
 			sb.append(getParameterString(FILTER));
 		}
 
 		if (sort)
 		{
 			sb.append(getParameterString(SORT));
 		}
 
 		if (page)
 		{
 			sb.append(getParameterString(PAGE));
 		}
 
 		sb.append(getParameterString(null)); //include any additional parameters
 
 		return sb.toString();
 	}
 
 	/***
 	 * Get all the action as hidden fields.
 	 */
 	public String getFormHiddenFields(boolean filter, boolean sort, boolean page)
 	{
 		StringBuffer sb = new StringBuffer();
 
 		if (filter)
 		{
 			sb.append(getHiddenFields(FILTER));
 		}
 
 		if (sort)
 		{
 			sb.append(getHiddenFields(SORT));
 		}
 
 		if (page)
 		{
 			sb.append(getHiddenFields(PAGE));
 		}
 
 		sb.append(getHiddenFields(null)); //include any additional parameters
 
 		return sb.toString();
 	}
 	
 	public void destroy()
 	{
 		parameters.clear();
 		parameters = null;
 	}
 }