/*
 *  RapidMiner
 *
 *  Copyright (C) 2001-2014 by RapidMiner and the contributors
 *
 *  Complete list of developers available at our web site:
 *
 *       http://rapidminer.com
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU Affero General Public License as published by
 *  the Free Software Foundation, either version 3 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 Affero General Public License for more details.
 *
 *  You should have received a copy of the GNU Affero General Public License
 *  along with this program.  If not, see http://www.gnu.org/licenses/.
 */
package com.rapidminer.gui.safemode;

import java.io.File;
import java.io.IOException;
import java.util.logging.Level;

import com.rapidminer.gui.tools.dialogs.ConfirmDialog;
import com.rapidminer.tools.FileSystemService;
import com.rapidminer.tools.I18N;
import com.rapidminer.tools.LogService;

/** Safe mode for RapidMiner. When {@link #launchStarts()} is called, a lock file is created.
 *  This lock file is deleted in {@link #launchComplete()}. If RapidMiner starts, and the lock
 *  file still exists when {@link #launchStarts()} is called, This class will ask the user whether
 *  they want to go into safe mode, which disables loading of all plugins.
 * 
 * @author Simon Fischer
 *
 */
public class SafeMode {

	private File lockFile;
	private boolean safeMode = false;

	public SafeMode() {
		lockFile = FileSystemService.getUserConfigFile("safeMode.lock");
	}

	/** Call at the beginning of the startup phase. */
	public void launchStarts() {
		if (lockFile.exists()) {
			// Lock file not deleted? Crashed during last startup 
			LogService.getRoot().log(Level.INFO, "com.rapidminer.gui.safemode.SafeMode.lock_left_behind", lockFile);
			safeMode = askForSafeMode();
			if(safeMode) {
				LogService.getRoot().log(Level.INFO, "com.rapidminer.gui.safemode.SafeMode.entering_safe_mode");
			}
		}
		// Create file on startup
		try {
			lockFile.createNewFile();
		} catch (IOException e) {
			LogService.getRoot().log(Level.INFO,
					I18N.getMessage(LogService.getRoot().getResourceBundle(),
							"com.rapidminer.gui.safemode.SafeMode.cannot_create_lock",
							lockFile),
					e);
		}
	}

	public void launchComplete() {
		if (lockFile.exists()) {
			// Delete lock on end of startup
			if (!lockFile.delete()) {
				LogService.getRoot().log(Level.WARNING, "com.rapidminer.gui.safemode.SafeMode.failed_to_delete_log_file", lockFile);
			}
		}
	}

	public boolean isSafeMode() {
		return safeMode;
	}

	private boolean askForSafeMode() {
		int result = SafeModeDialog.showSafeModeDialog("safemode.enter_safe_mode", ConfirmDialog.YES_NO_OPTION);
		return result == ConfirmDialog.YES_OPTION;
	}

}