/*
    * Copyright 2010-2012 Capgemini
    * 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 net.sf.appstatus.web;
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.util.Map;
  import java.util.Properties;
  
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  
  import org.apache.commons.lang3.StringUtils;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import net.sf.appstatus.core.AppStatus;
  import net.sf.appstatus.core.AppStatusStatic;
  import net.sf.appstatus.web.pages.Resources;
  
  /**
   * Handle the Web UI of AppStatus.
   *
   * @author Olivier Lafon
   * @author Nicolas Richeton
   */
  public class StatusWebHandler {
  	private static Logger logger = LoggerFactory.getLogger(StatusWebHandler.class);
  	private String allowIp = null;
  	private String applicationName = StringUtils.EMPTY;
  	private AppStatus appStatus = null;
  	private String cssLocation = null;
  	private Map<String, IPage> pages = null;
  
  	/**
  	 * Handle a GET request.
  	 *
  	 * @param req
  	 * @param resp
  	 * @throws IOException
  	 */
  	public void doGet(final HttpServletRequest req, final HttpServletResponse resp) throws IOException {
  
  		if (allowIp != null) {
  			if (!req.getRemoteAddr().equals(allowIp)) {
  				resp.sendError(401, "IP not authorized");
  				return;
  			}
  		}
  
  		if (req.getParameter("icon") != null || req.getParameter("resource") != null) {
  			Resources.doGet(this, req, resp);
  			return;
  		}
  
  		if (req.getParameter("p") != null && pages.containsKey(req.getParameter("p"))) {
  			pages.get(req.getParameter("p")).doGet(this, req, resp);
  
  		} else {
  			pages.get("status").doGet(this, req, resp);
  		}
  	}
  
  	/**
  	 * Handle a POST request.
  	 *
  	 * @param req
  	 * @param resp
  	 * @throws IOException
  	 */
  	public void doPost(final HttpServletRequest req, final HttpServletResponse resp) throws IOException {
  		if (allowIp != null) {
  			if (!req.getRemoteAddr().equals(allowIp)) {
  				resp.sendError(401, "IP not authorized");
  				return;
  			}
  		}
  
  		if (req.getParameter("p") != null && pages.containsKey(req.getParameter("p"))) {
  			pages.get(req.getParameter("p")).doPost(this, req, resp);
  
  		} else {
  			pages.get("status").doPost(this, req, resp);
  		}
  
  		doGet(req, resp);
 	}
 
 	public String getApplicationName() {
 		return applicationName;
 	}
 
 	public AppStatus getAppStatus() {
 		return appStatus;
 	}
 
 	public String getCssLocation() {
 		return cssLocation;
 	}
 
 	public Map<String, IPage> getPages() {
 		return pages;
 	}
 
 	/**
 	 * Does the initialization work.
 	 * <p>
 	 * Read configuration from /status-web-conf.properties
 	 * <p>
 	 * If you need to inject custom objects using these methods, please do it
 	 * before calling init.
 	 * <ul>
 	 * <li>{@link #setPages(Map)}</li>
 	 * <li>{@link #setAppStatus(AppStatus)}</li>
 	 * <li>{@link #setCssLocation(String)}</li>
 	 * </ul>
 	 */
 	public void init() {
 
 		// init AppStatus
 		if (appStatus == null) {
 			// Use default instance if not set
 			appStatus = AppStatusStatic.getInstance();
 		}
 
 		appStatus.init();
 
 		// Load specific configuration
 		try {
 			final InputStream is = Thread.currentThread().getContextClassLoader()
 					.getResourceAsStream("/status-web-conf.properties");
 
 			if (is == null) {
 				logger.warn("/status-web-conf.properties not found in classpath. Using default configuration");
 			} else {
 				final Properties p = new Properties();
 				p.load(is);
 				is.close();
 
 				if (allowIp == null) {
 					allowIp = (String) p.get("ip.allow");
 				}
 			}
 		} catch (final Exception e) {
 			logger.error("Error loading configuration from /status-web-conf.properties.", e);
 		}
 
 		// Init css & js
 		if (cssLocation == null) {
 			cssLocation = "?resource=appstatus.css";
 			Resources.addResource("appstatus.css", "/assets/css/appstatus.css", "text/css");
 			Resources.addResource("bootstrap.js", "/assets/js/bootstrap.js", "application/javascript");
 			Resources.addResource("jquery.js", "/assets/js/jquery-2.0.1.min.js", "application/javascript");
 			Resources.addResource("glyphicons-halflings.png", "/assets/img/glyphicons-halflings.png", "image/png");
 			Resources.addResource("glyphicons-halflings-white.png", "/assets/img/glyphicons-halflings-white.png",
 					"image/png");
 		}
 	}
 
 	/**
 	 * Restrict access to a single IP.
 	 *
 	 * @param allowIp
 	 */
 	public void setAllowIp(final String allowIp) {
 		this.allowIp = allowIp;
 	}
 
 	public void setApplicationName(final String servletContextName) {
 		this.applicationName = servletContextName;
 	}
 
 	/**
 	 * Set the AppStatus object to use in the web interface.
 	 *
 	 * @param appStatus
 	 */
 	public void setAppStatus(final AppStatus appStatus) {
 		this.appStatus = appStatus;
 	}
 
 	/**
 	 * Set the location of the css to use.
 	 *
 	 * @param cssLocation
 	 */
 	public void setCssLocation(final String cssLocation) {
 		this.cssLocation = cssLocation;
 	}
 
 	/**
 	 * Set the available pages in the web interface.
 	 *
 	 * @param pages
 	 */
 	public void setPages(final Map<String, IPage> pages) {
 		this.pages = pages;
 	}
 }