/**
 *  '$RCSfile$'
 *    Purpose: A Class that implements database configuration methods
 *  Copyright: 2008 Regents of the University of California and the
 *             National Center for Ecological Analysis and Synthesis
 *    Authors: Michael Daigle
 * 
 *   '$Author: daigle $'
 *     '$Date: 2008-07-24 13:47:03 -0700 (Thu, 24 Jul 2008) $'
 * '$Revision: 4155 $'
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package edu.ucsb.nceas.metacat.admin;

import java.util.Vector;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.log4j.Logger;

import edu.ucsb.nceas.metacat.properties.PropertyService;
import edu.ucsb.nceas.metacat.shared.MetacatUtilException;
import edu.ucsb.nceas.metacat.util.GeoserverUtil;
import edu.ucsb.nceas.metacat.util.RequestUtil;
import edu.ucsb.nceas.metacat.util.SystemUtil;
import edu.ucsb.nceas.utilities.FileUtil;
import edu.ucsb.nceas.utilities.GeneralPropertyException;

/**
 * Control the display of the database configuration page and the processing
 * of the configuration values.
 */
public class GeoserverAdmin extends MetacatAdmin {

	private static GeoserverAdmin geoserverAdmin = null;
	private Logger logMetacat = Logger.getLogger(GeoserverAdmin.class);

	/**
	 * private constructor since this is a singleton
	 */
	private GeoserverAdmin() throws AdminException {

	}

	/**
	 * Get the single instance of GeoserverAdmin.
	 * 
	 * @return the single instance of GeoserverAdmin
	 */
	public static GeoserverAdmin getInstance() throws AdminException {
		if (geoserverAdmin == null) {
			geoserverAdmin = new GeoserverAdmin();
		}
		return geoserverAdmin;
	}

	/**
	 * Handle configuration of the database the first time that Metacat starts
	 * or when it is explicitly called. Collect necessary update information
	 * from the administrator.
	 * 
	 * @param request
	 *            the http request information
	 * @param response
	 *            the http response to be sent back to the client
	 */
	public void configureGeoserver(HttpServletRequest request,
			HttpServletResponse response) throws AdminException {

		String processForm = request.getParameter("processForm");
		String bypass = request.getParameter("bypass");
		String formErrors = (String) request.getAttribute("formErrors");

		if (processForm == null || !processForm.equals("true") || formErrors != null) {
			// The servlet configuration parameters have not been set, or there
			// were form errors on the last attempt to configure, so redirect to
			// the web form for configuring metacat

			try {
				// get the current configuration values
				String username = PropertyService.getProperty("geoserver.username");
				String password = PropertyService.getProperty("geoserver.password");
				String context = PropertyService.getProperty("geoserver.context");
				String dataDir = PropertyService.getProperty("geoserver.GEOSERVER_DATA_DIR");
				String regenerateCache = PropertyService.getProperty("spatial.regenerateCacheOnRestart");
				boolean regenerate = false;
				if (regenerateCache != null) {
					regenerate = Boolean.parseBoolean(regenerateCache);
				}
				
				// provide a default based on the current installation
				if (dataDir == null || dataDir.length() == 0) {
					dataDir = 
						SystemUtil.getContextDir()
						+ FileUtil.getFS()
						+ "spatial"
						+ FileUtil.getFS()
						+ "geoserver"
						+ FileUtil.getFS()
						+ "data";
				}
				
				request.setAttribute("geoserver.username", username);
				request.setAttribute("geoserver.password", password);
				request.setAttribute("geoserver.context", context);
				request.setAttribute("geoserver.GEOSERVER_DATA_DIR", dataDir);
				request.setAttribute("spatial.regenerateCacheOnRestart", regenerate);

				// Forward the request to the JSP page
				RequestUtil.forwardRequest(request, response,
						"/admin/geoserver-configuration.jsp", null);
			} catch (GeneralPropertyException gpe) {
				throw new AdminException("GeoserverAdmin.configureGeoserver - Problem getting or " + 
						"setting property while initializing system properties page: " + gpe.getMessage());
			} catch (MetacatUtilException mue) {
				throw new AdminException("GeoserverAdmin.configureGeoserver - utility problem while initializing "
						+ "system properties page:" + mue.getMessage());
			} 
		} else if (bypass != null && bypass.equals("true")) {
			Vector<String> processingErrors = new Vector<String>();
			Vector<String> processingSuccess = new Vector<String>();
			
			// Bypass the geoserver configuration. This will not keep
			// Metacat from running.
			try {
				PropertyService.setProperty("configutil.geoserverConfigured",
						PropertyService.BYPASSED);
				
			} catch (GeneralPropertyException gpe) {
				String errorMessage = "GeoserverAdmin.configureGeoserver - Problem getting or setting property while "
					+ "processing system properties page: " + gpe.getMessage();
				logMetacat.error(errorMessage);
				processingErrors.add(errorMessage);
			}
			try {
				if (processingErrors.size() > 0) {
					RequestUtil.clearRequestMessages(request);
					RequestUtil.setRequestErrors(request, processingErrors);
					RequestUtil.forwardRequest(request, response, "/admin", null);
				} else {			
					// Reload the main metacat configuration page
					processingSuccess.add("Geoserver configuration successfully bypassed");
					RequestUtil.clearRequestMessages(request);
					RequestUtil.setRequestSuccess(request, processingSuccess);
					RequestUtil.forwardRequest(request, response, 
							"/admin?configureType=configure&processForm=false", null);
				}
			} catch (MetacatUtilException mue) {
				throw new AdminException("GeoserverAdmin.configureGeoserver - utility problem while processing geoservices "
						+ "geoservices page: " + mue.getMessage());
			} 
		
		} else {
			// The configuration form is being submitted and needs to be
			// processed, setting the properties in the configuration file
			// then restart metacat

			// The configuration form is being submitted and needs to be
			// processed.
			Vector<String> validationErrors = new Vector<String>();
			Vector<String> processingErrors = new Vector<String>();
			Vector<String> processingSuccess = new Vector<String>();

			try {
				// Validate that the options provided are legitimate. Note that
				// we've allowed them to persist their entries. As of this point
				// there is no other easy way to go back to the configure form
				// and preserve their entries.
				validationErrors.addAll(validateOptions(request));
				
				String username = (String)request.getParameter("geoserver.username");
				String password = (String)request.getParameter("geoserver.password");
				String context = (String)request.getParameter("geoserver.context");
				String dataDir = (String)request.getParameter("geoserver.GEOSERVER_DATA_DIR");
				String regenerateCache = (String)request.getParameter("spatial.regenerateCacheOnRestart");
				boolean regenerate = false;
				if (regenerateCache != null) {
					regenerate = Boolean.parseBoolean(regenerateCache);
				}

				
				// process the context/data dir
				if (context == null || dataDir == null) {
					validationErrors.add("Context and Data Directory cannot be null");
				} else {
					PropertyService.setPropertyNoPersist("geoserver.context", context);
					boolean reconfig = PropertyService.checkAndSetProperty(request, "geoserver.GEOSERVER_DATA_DIR");
					PropertyService.persistProperties();
					// put the web.xml in place
					reconfig = true; //force all the time in cases where geoserver has been redeployed
					if (reconfig) {
						GeoserverUtil.writeConfig();
					}
				}
				
				if (username == null || password == null) {
					validationErrors.add("User Name and Password cannot be null");
				} else {
					GeoserverUtil.changePassword(username, password);
					PropertyService.setPropertyNoPersist("geoserver.username", username);
					PropertyService.setPropertyNoPersist("geoserver.password", password);
					PropertyService.setPropertyNoPersist("spatial.regenerateCacheOnRestart", Boolean.toString(regenerate));
					PropertyService.persistProperties();

					// write the backup properties to a location outside the
					// application directories so they will be available after
					// the next upgrade
					PropertyService.persistMainBackupProperties();
				}
			} catch (MetacatUtilException ue) {
				String errorMessage = "GeoserverAdmin.configureGeoserver - Error updating geoserver password: " + ue.getMessage();
				logMetacat.error(errorMessage);
				processingErrors.add(errorMessage);
			} catch (GeneralPropertyException gpe) {
				String errorMessage = "GeoserverAdmin.configureGeoserver - Problem getting or setting property while "
						+ "processing system properties page: " + gpe.getMessage();
				logMetacat.error(errorMessage);
				processingErrors.add(errorMessage);
			}

			try {
				if (validationErrors.size() > 0 || processingErrors.size() > 0) {
					RequestUtil.clearRequestMessages(request);
					RequestUtil.setRequestFormErrors(request, validationErrors);
					RequestUtil.setRequestErrors(request, processingErrors);
					RequestUtil.forwardRequest(request, response, "/admin", null);
				} else {
					// Now that the options have been set, change the
					// 'propertiesConfigured' option to 'true'
					PropertyService.setProperty("configutil.geoserverConfigured",
							PropertyService.CONFIGURED);
					
					// Reload the main metacat configuration page
					processingSuccess.add("Geoserver successfully configured");
					RequestUtil.clearRequestMessages(request);
					RequestUtil.setRequestSuccess(request, processingSuccess);
					RequestUtil.forwardRequest(request, response, 
							"/admin?configureType=configure&processForm=false", null);
				}
			} catch (MetacatUtilException mue) {
				throw new AdminException("GeoserverAdmin.configureGeoserver - utility problem while processing geoservices "
						+ "geoservices page: " + mue.getMessage());
			} catch (GeneralPropertyException gpe) {
				throw new AdminException("GeoserverAdmin.configureGeoserver - problem with properties while "
						+ "processing geoservices configuration page: " + gpe.getMessage());
			}
		}
	}

	/**
	 * Validate the most important configuration options submitted by the user.
	 * 
	 * @return a vector holding error message for any fields that fail
	 *         validation.
	 */
	protected Vector<String> validateOptions(HttpServletRequest request) {
		Vector<String> errorVector = new Vector<String>();

		// TODO MCD validate options.

		return errorVector;
	}
}
