/*
    * Copyright 2004-2006 the Seasar Foundation and the Others.
    *
    * 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.seasar.tuigwaa.plugin.misc;
  
  import java.text.ParseException;
  import java.text.SimpleDateFormat;
  import java.util.Calendar;
  import java.util.Collections;
  import java.util.Comparator;
  import java.util.Date;
  import java.util.GregorianCalendar;
  import java.util.Iterator;
  import java.util.List;
  
  import org.seasar.tuigwaa.cms.core.CmsConstants;
  import org.seasar.tuigwaa.cms.core.CmsRequest;
  import org.seasar.tuigwaa.cms.core.CmsResponse;
  import org.seasar.tuigwaa.cms.core.Page;
  import org.seasar.tuigwaa.cms.core.Resource;
  import org.seasar.tuigwaa.cms.core.wiki.WikiContext;
  import org.seasar.tuigwaa.plugin.AbstractTgwPlugin;
  import org.seasar.tuigwaa.plugin.PluginException;
  import org.seasar.tuigwaa.plugin.PluginRequest;
  import org.seasar.tuigwaa.plugin.basic.CalendarPlugin;
  import org.seasar.tuigwaa.system.TgwSecurityException;
  
  import com.isenshi.util.CharUtil;
  import com.isenshi.util.HtmlBuffer;
  
  /***
   * @author someda
   */
  public class CalendarviewerPlugin extends AbstractTgwPlugin {
  
  	private static final int DEFAULT_NUM = 10;
  
  	private static final int MODE_PAST = 1;
  
  	private static final int MODE_FUTURE = 2;
  
  	private static final int MODE_VIEW = 3;
  
  	private static final int DEFAULT_MODE = MODE_PAST;
  	
  	private static String FILENAME_FORMAT = getMessage("calendarviewer.datestyle");
  	private static SimpleDateFormat FILENAME_DATEFORMAT = new SimpleDateFormat(FILENAME_FORMAT);
  	private static String DISPLAY_FORMAT = getMessage("calendarviewer.displaystyle");
  	private static SimpleDateFormat FILENAME_DISPLAYFORMAT = new SimpleDateFormat(DISPLAY_FORMAT);
  
  	private int mode = DEFAULT_MODE;
  
  	public String doHTMLView(CmsRequest request, CmsResponse response,
  			PluginRequest prequest) throws PluginException {
  
  		String[] args = prequest.getArgs();
  		String pagename = null;
  
  		if (args != null && args.length > 0)
  			pagename = args[0];
  
  		if (pagename == null)
  			pagename = request.getPage().getResource().getPath();
  
  		int num = DEFAULT_NUM;
  		String month = null;
  		if (args != null && args.length > 1) {
  			try {
  				num = Integer.parseInt(args[1]);
  			} catch (NumberFormatException nfe) {
  				if (args[1].indexOf("-") != -1)
  					month = args[1];
  			}
  		}
  
  		mode = getMode(args);
  
  		Calendar cal = new GregorianCalendar();
  		String today = CmsConstants.CALENDARFORMAT.format(cal.getTime());
  
  		WikiContext context = getConfiguration().getWikiContext();
  
  		List list;
  		try {
  			String path;
  			int idx;
  			if ((idx = pagename.lastIndexOf("/")) == -1) {
 				path = "";
 			} else {
 				path = pagename.substring(0, idx);
 			}
 
 			list = context.getResourceList(request, path);
 		} catch (Exception e) {
 			throw new PluginException(e);
 		}
 		return getHtml(list, context, request, pagename, num, month, today);
 	}
 
 	private String getHtml(List list, WikiContext context, CmsRequest request,
 			String pagename, int num, String month, String today)
 			throws PluginException {
 
 		if (list == null || list.size() == 0) {
 			return CharUtil.replace(getMessage("calendarviewer.notfound"),
 					pagename);
 		}
 
 		String fileprefix = pagename + CalendarPlugin.PAGENAME_APPENDER;
 
 
 		
 		HtmlBuffer buf = new HtmlBuffer();
 		buf.appendHeading(2, CharUtil.replace(
 				getMessage("calendarviewer.list"), pagename));
 
 		sortList(list);
 		for (int i = 0; i < list.size(); i++) {
 			Resource resource = (Resource) list.get(i);
 
 			if (filterByName(list, resource, fileprefix)) {
 				i--;
 				continue;
 			}
 
 			String resourcename = resource.getPageName();
 			int idx = resourcename.indexOf(CalendarPlugin.PAGENAME_APPENDER);
 			String suffix = resourcename.substring(idx + 1);
 
 			if (filterByMonth(list, resource, suffix, month)) {
 				i--;
 				continue;
 			}
 
 			if (filterByMode(list, resource, suffix, today, mode)) {
 				i--;
 				continue;
 			}
 		}
 		
 		if (month == null)
 			filterByNum(list, num);
 
 		for (Iterator i = list.iterator(); i.hasNext();) {
 			Resource res = (Resource) i.next();
 			String pagepath = res.getPath();
 
 			assertIncludePage(request, pagepath);
 
 			request.pushScope();
 			Page page = getPage(request, pagepath);
 			request.popScope();
 
 			String pageDate = pagepath.replaceAll(fileprefix, "");
 			try{
 				Date date = FILENAME_DATEFORMAT.parse(pageDate);
 				pageDate = FILENAME_DISPLAYFORMAT.format(date);
 			}catch(ParseException pe){
 				// do nothing
 			}			
 			
 			try{
 				String uri = context.getURLByName(pagepath, request).toString();
 				
 				buf.appendStartTag("h3");
 				buf.appendAnchor(uri, pageDate);
 				buf.endTag();
 			}catch(TgwSecurityException tse){
 				// do-nothing security link
 			}
 
 			buf.appendBody(page.getContent().toString());
 		}
 		return buf.toString();
 	}
 
 	// ----- [Start] private methods -----
 
 	private void sortList(List list) {
 		// sort depending on view-mode
 		Collections.sort(list, new Comparator() {
 			public int compare(Object left, Object right) {
 
 				Resource res1 = (Resource) left;
 				Resource res2 = (Resource) right;
 
 				if (res1.isFolder() && res2.isFile()) {
 					return -1;
 				} else if (res1.isFile() && res2.isFolder()) {
 					return 1;
 				} else {
 					int weight = 1;
 					if (mode == MODE_PAST || mode == MODE_VIEW)
 						weight = -1;
 					return weight * res1.getPath().compareTo(res2.getPath());
 				}
 			}
 		});
 	}
 
 	private boolean filterByName(List list, Resource resource, String name) {
 		boolean filtered = false;
 		if (resource.getPath().indexOf(name) == -1) {
 			list.remove(resource);
 			filtered = true;
 		}
 		return filtered;
 	}
 
 	private boolean filterByMonth(List list, Resource resource, String suffix,
 			String month) {
 		if (month == null)
 			return false;
 
 		boolean filtered = false;
 		if (!suffix.startsWith(month)) {
 			list.remove(resource);
 			filtered = true;
 		}
 		return filtered;
 	}
 
 	private boolean filterByMode(List list, Resource resource, String suffix,
 			String today, int mode) {
 		if (mode == MODE_VIEW)
 			return false;
 
 		boolean filtered = false;
 		if (mode == MODE_PAST) {
 			if (suffix.compareTo(today) > 0)
 				filtered = true;
 		} else if (mode == MODE_FUTURE) {
 			if (suffix.compareTo(today) < 0)
 				filtered = true;
 		}
 		if (filtered)
 			list.remove(resource);
 		return filtered;
 	}
 
 	private boolean filterByNum(List list, int num) {
 		boolean filtered = false;
 		while (list.size() > num) {
 			filtered = true;
 			list.remove(list.size() - 1);
 		}
 		return filtered;
 	}
 
 	// ----- [End] private methods -----
 
 	// ----- [Start] static methods -----
 	private static int getMode(String[] args) {
 		int m = DEFAULT_MODE;
 		if (args != null && args.length > 2) {
 			if (args[2].equals("past")) {
 				m = MODE_PAST;
 			} else if (args[2].equals("future")) {
 				m = MODE_FUTURE;
 			} else if (args[2].equals("view")) {
 				m = MODE_VIEW;
 			}
 		}
 		return m;
 	}
 }