/**
 *    Browser.java
 *    Copyright (C) 2010 New Zealand Digital Library, http://expeditee.org
 *
 *    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 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 General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package org.expeditee.gui;

import java.io.File;
import java.io.IOException;
import java.net.Authenticator;
import java.security.KeyStoreException;
import java.security.NoSuchAlgorithmException;
import java.security.cert.CertificateException;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.Collection;

import org.expeditee.actions.Actions;
import org.expeditee.actions.Simple;
import org.expeditee.agents.mail.MailSession;
import org.expeditee.auth.AuthenticatorBrowser;
import org.expeditee.core.BlockingRunnable;
import org.expeditee.core.Colour;
import org.expeditee.core.Dimension;
import org.expeditee.core.Point;
import org.expeditee.gio.EcosystemManager;
import org.expeditee.gio.EcosystemManager.Ecosystem;
import org.expeditee.gio.GraphicsManager;
import org.expeditee.gio.InputManager;
import org.expeditee.gio.InputManager.WindowEventListener;
import org.expeditee.gio.InputManager.WindowEventType;
import org.expeditee.gio.gesture.StandardGestureActions;
import org.expeditee.io.ProxyAuth;
import org.expeditee.items.Item;
import org.expeditee.items.ItemUtils;
import org.expeditee.items.Text;
import org.expeditee.items.widgets.JfxBrowser;
import org.expeditee.items.widgets.WidgetCacheManager;
import org.expeditee.network.FrameShare;
import org.expeditee.settings.Settings;
import org.expeditee.settings.UserSettings;
import org.expeditee.stats.Logger;
import org.expeditee.stats.StatsLogger;
import org.expeditee.taskmanagement.EntitySaveManager;
import org.expeditee.taskmanagement.SaveStateChangedEvent;
import org.expeditee.taskmanagement.SaveStateChangedEventListener;

import javafx.application.Platform;

/**
 * The Main GUI class, comprises what people will see on the screen.<br>
 * Note: Each Object (Item) is responsible for drawing itself on the screen.<br>
 * Note2: The Frame is registered as a MouseListener and KeyListener, and
 * processes any Events.
 * 
 * TODO List:
 * 
 * Back to standard:
 *  - JavaFX Text-hitting (requires JFX1.9)
 *  - Overlays and Vectors review
 *  - Pop-ups (unused in base Expeditee, only in Apollo)
 *  - Apollo input (test)
 *  - The rest of Apollo
 *  - Make sure clipping/invalidation takes twin-frames into account
 *  - Reinstate Simple input commands
 *  - Test LinkedTrack.paintInFreeSpace()
 *  - Test EmulatedTextItem.onMouseReleased(MouseEvent) (removed emulatedSource mouse button check)
 *  - Constrained placement of items
 *  
 * Extra:
 *  - Self-describing input
 *  - Thread safety (most stuff on GIO event thread but Agents can start new threads)
 *  - Touch input
 *  - Better reflection??? (currently changes to the code break reflection as it relies on names)
 *  - JavaFX lag (always rendering to images doesn't gel well with JavaFX)
 *  - Swing widgets in JFX
 *  - JavaFX Widgets (exception on drawing?)
 *  - Reduce reliance on into-image rendering to improve JavaFX performance (utilise enforced-clip)
 *  - Block Swing ecosystem setup until window is available, or...
 *  - Reconfigure window-resized code so things are properly resized (PREFERRED).
 *  - Swing alpha-compositing of colours (currently alpha is ignored e.g. drop-shadow in transition).
 *  - Overly-thick extrusion lines (seems to depend on number of connected lines...)
 *  - Make FreeItems control pickup etc.
 *  - Remove MouseEventRouter
 *  - Highlighting (should be controlled by the items themselves)
 *  - Make Widgets into fully-fledged items (maybe???)
 *  - Merge Widget and HeavyDutyWidget
 *  - Redefine TextLayouts (relative/absolute layouts)
 *  - Settings exceptions (Password widget in JFX) (currently fixed with hack)
 *  - MessageBay (what did I mean by this specifically?)
 *  - Order-dependency of start-up code
 *  - MessageBay not refreshing at start-up
 *  - Invalidation hierarchy (item => frame => display controller area => window)
 *  - Add gesture data type checking
 *  - Paintable interface
 *  - EcosystemSpecific interface (utilise to enable/disable features based on ecosystem)
 *  - Remove/modify Mutable class (in Apollo.util, change to InOutReference)
 *  - Convert BlockingRunnable to interface
 *  - Modify Metronome to utilise Timeouts
 *  - Need AWT in FastAlphaEffect???
 *  
 * General:
 *  - Tidy FrameGraphics
 *  - Comment
 *  - UserSettings.DEFAULT_PROFILE_NAME not actually a user setting
 * 
 * Done:
 *  - Timers
 *  - Timer input animations
 *  - Finish DisplayController/FrameGraphics separation
 *  - Anchor constraints (create class)
 *  - Make MessageBay take lead from DisplayController
 *  - Make message bay display again (to do with above)
 *  - Tooltips (layout broken in Swing as window size not correct when tooltips laid out)
 *  - Frame transitions
 *  - Frame transitions in twin-frames mode drawing over each other
 *  - JFX DnD manager
 *  - Reinstate Simple
 *  - Reinstate exclude source
 *  - Reinstate commented code
 *  - Twin-frames division 0 at startup
 *  - Twin frames off-by-one frame size (draws a line of erroneous pixels)
 *  - MessageBay delays showing messages on start-up
 *  - JFX Antialiasing done on theScene??? Doesn't apply for our situation
 *  - Incorporate Clip class into code
 *  - Enforced clip
 * 
 * @author cts16
 * @author jdm18
 */
public class Browser implements SaveStateChangedEventListener {
	
	public static final boolean DEBUG = true;
	
	public static final Ecosystem ECOSYSTEM_TYPE = Ecosystem.Swing;

	public static Browser _theBrowser = null;
	
	public static ProxyAuth proxyAuth = new ProxyAuth();

	public static boolean _hasExited = false;

	/** A flag which is set once the application is exiting. */
	protected boolean _isExiting = false;

	protected static boolean _initComplete = false;
	
	private static String _startFrame = null;


	/**
	 * Constructs a new Browser object, then launches it
	 * 
	 * @param args
	 */
	public static void main(String[] args) {
		if (AuthenticatorBrowser.isAuthenticationRequired()) {
			String starting_user_name = System.getProperty("user.name");
			System.setProperty("startinguser.name", starting_user_name);
			System.setProperty("user.name", AuthenticatorBrowser.USER_NOBODY);
		}
		
		// Parse the starting frame command-line argument
		if(args.length > 0) {
			setStartFrame(args[0]);
			if(!Character.isDigit(getStartFrame().charAt(getStartFrame().length() - 1))) {
				setStartFrame(getStartFrame() + "1");
			}
		} else {
		    setStartFrame("home1");
		}

		// Window icon must be set before initialisation
		GraphicsManager.setWindowIcon(DisplayController.ICON_IMAGE);
		
		// Setup the GIO ecosystem so it is ready when we need it
		EcosystemManager.createEcosystem(ECOSYSTEM_TYPE);
		
		try {
			EcosystemManager.getMiscManager().runOnGIOThread(new BlockingRunnable() {
				@Override
				public void execute() {
					init();
					MessageBay.showDelayedMessages(true);
				}
			});
		} catch (Throwable e) {
			e.printStackTrace(System.err);
			System.exit(1);
		}
		
		//MessageBay.showDelayedMessages(true);
	}
	
	public static void init() {
		if (AuthenticatorBrowser.isAuthenticationRequired()) {
			try {
				_theBrowser = AuthenticatorBrowser.getInstance();
			} catch (KeyStoreException | NoSuchAlgorithmException | CertificateException | IOException | ClassNotFoundException | SQLException e) {
				e.printStackTrace();
			}
		} else {
			_theBrowser = new Browser();
		}		

		EcosystemManager.getGraphicsManager().requestFocus();
		
		// Java's way of getting access to internet.  Authenticating the user with their proxy username and password.
		Authenticator.setDefault(proxyAuth);
		
		_initComplete = true;
	}

	/**
	 * @return
	 * 
	 * True if the application is about to exit. False if not. Note that this is
	 * only set once the window is in its closed state (not closing) or if the
	 * application has explicitly being requested to exit.
	 * 
	 * @see Browser#exit()
	 * 
	 */
	public boolean isExiting() {
		return _isExiting;
	}

	public static boolean isInitComplete() {
		return _initComplete;
	}
	
	protected Browser(String mode) {
		System.out.println("Running Expeditee in " + mode + " mode.");
	}

	protected Browser() {
		// center the frame on the screen
		GraphicsManager g = EcosystemManager.getGraphicsManager();
		Dimension screen = g.getScreenSize();
		double xpos = (screen.width - UserSettings.InitialWidth.get()) / 2.0;
		double ypos = (screen.height - UserSettings.InitialHeight.get()) / 2.0;
		g.setWindowLocation(new Point((int) xpos, (int) ypos));

		DisplayController.Init();

		DisplayController.addDisplayObserver(WidgetCacheManager.getInstance());
		if (ECOSYSTEM_TYPE == Ecosystem.Swing) {
			DisplayController.addDisplayObserver(PopupManager.getInstance());
		}

		setInputManagerWindowRoutines();

		// Reset windows to user specified size
		Dimension initialWindowSize = new Dimension(UserSettings.InitialWidth.get(), UserSettings.InitialHeight.get());
		g.setWindowSize(initialWindowSize);

		// Load documentation and start pages
		FrameUtils.extractResources(false);

		// Load fonts before loading any frames so the items on the frames will be able
		// to access their fonts
		Text.InitFonts();

		if (!AuthenticatorBrowser.isAuthenticationRequired() && UserSettings.PublicAndPrivateResources) {
			String userName = System.getProperty("user.name"); //UserSettings.ProfileName.get();
			if (!FrameIO.personalResourcesExist(userName)) {
				FrameIO.setupPersonalResources(userName);
			}
		}
		
		Settings.Init();
		Frame userProfile = loadInitialProfiles();
		FrameIO.changeParentAndSubFolders(FrameIO.PARENT_FOLDER);
		
		// Listen for save status to display during and after runtime
		EntitySaveManager.getInstance().addSaveStateChangedEventListener(this);

		try {
			MessageBay.warningMessages(Actions.Init());
			
			// Go to the start frame if specified, otherwise go to the profile frame
			if (getStartFrame() == null) {
				setStartFrame(UserSettings.StartFrame.get());
				if (getStartFrame() != null && !Character.isDigit(getStartFrame().charAt(getStartFrame().length() - 1))) {
					setStartFrame(getStartFrame() + "1");
				}
			}

			Frame start = null;
			if ((start = FrameIO.LoadFrame(getStartFrame())) != null) {
				// Make sure HomeFrame gets set
				UserSettings.HomeFrame.set(start.getName());

				// Go to the start frame
				DisplayController.setCurrentFrame(start, true);
			} else {
				// If an invalid start frame was specified, show a warning
				if (getStartFrame() != null) {
					MessageBay.warningMessage("Unknown frame: " + getStartFrame());
				}

				// Go to the profile frame
				FrameUtils.loadFirstFrame(userProfile);
			}

			DisplayController.updateTitle();

			// Don't refresh for the profile frame otherwise error messages are shown twice
			if (!DisplayController.getCurrentFrame().equals(userProfile)) {
				StandardGestureActions.Refresh();
				// If it's the profile frame just reparse it in order to display
				// images/circles/widgets correctly
			} else {
				FrameUtils.Parse(userProfile);
			}
		} catch (Exception e) {
			e.printStackTrace();
			Logger.Log(e);
		}
	}

	@Override
	public void saveCompleted(SaveStateChangedEvent event)
	{
		MessageBay.displayMessage("Save finished!", Colour.BLUE);
	}

	@Override
	public void saveStarted(SaveStateChangedEvent event)
	{
		String name = event.getEntity().getSaveName();
		if (name == null) {
			name = "data";
		}
		MessageBay.displayMessage("Saving " + name + "...", Colour.BLUE);
	}

	/**
	 * Closes the browser and ends the application. Performs saving operations -
	 * halting until saves have completed. Feedback is given to the user while
	 * the application is exiting. Must call on the swing thread.
	 */
	public void exit() {

		// Set exiting flag
		_isExiting = true;

		MessageBay.displayMessage("System exiting...");

		/**
		 * TODO: Prompt the user etc.
		 */

		// TODO: Should we should a popup with a progress bar for user feedback?
		// this would be nice and easy to do.
		// Exit on a dedicated thread so that feedback can be obtained
		new Exiter().start(); // this will exit the application
	}

	/**
	 * The system must exit on a different thread other than the swing thread so
	 * that the save threads can fire save-feedback to the swing thread and thus
	 * provide user feedback on asynchronous save operations.
	 * 
	 * @author Brook Novak
	 * 
	 */
	private class Exiter extends Thread {

		@Override
		public void run() {

			// The final save point for saveable entities
			EntitySaveManager.getInstance().saveAll();
			try {
				EntitySaveManager.getInstance().waitUntilAllSavingFinished();
			} catch (InterruptedException e) {
				e.printStackTrace();
			}
			
			// Stop any agents or simple programs
			Simple.stop();
			Actions.stopAgent();
			// Wait for them to stop
			try {
				// Only stop if need to...
				// Brook: What purpose does this serve?
				MessageBay.displayMessage("Stopping Simple programs...");
				while (Simple.isProgramRunning()) {
					Thread.sleep(100);
				}
				
				MessageBay.displayMessage("Stopping Agents...");
				/* TODO: Only stop if need to... */
				while (Actions.isAgentRunning()) {
					Thread.sleep(100); // Brook: What purpose does this serve?
				}
			} catch (Exception e) {

			}

			MessageBay.displayMessage("Saving current frame...");
			FrameIO.SaveFrame(DisplayController.getCurrentFrame());

			MessageBay.displayMessage("Saving stats...");
			StatsLogger.WriteStatsFile();

			if (MailSession.getInstance() != null) {
				if (MailSession.getInstance().finalise()) {
					// TODO display this message before the finalising
					// is done but only if the mail needs closing
					MessageBay.displayMessage("Closed ExpMail...");
				}
			}

			if (FrameShare.getInstance() != null) {
				MessageBay.displayMessage("Stopping FrameServer...");
				FrameShare.getInstance().finalise();
			}
			
			// Shut down the Java FX Platform.  
			if (JfxBrowser.JFXBROWSER_IN_USE) {
				MessageBay.displayMessage("Detected use of JFX Browser.  Stopping Java FX Platform...");
				Platform.exit();
			}
			
			MessageBay.displayMessage("System exited");

			// Finally remove the messages frameset
			FrameIO.moveFrameset("messages", FrameIO.MESSAGES_PATH, false);

			/*
			 * Create a new messages folder so that it doesn't throw
			 * Exceptions when two Expeditee's open at once and the
			 * second tries to save its messages
			 */
			File file = new File(FrameIO.MESSAGES_PATH + "messages");
			file.mkdirs();
			
			Browser._hasExited = true;
			
			System.exit(0);
		}
	}

	/**
	 * Used to set up the the browser for use in testing.
	 * 
	 * @return
	 */
	public static Browser initializeForTesting()
	{
		if (Browser._theBrowser == null) {
			FrameShare.disableNetworking = true;
			MailSession._autoConnect = false;

			Browser.main(new String[]{});
			try {
				while (!isInitComplete()) {
					Thread.sleep(10);
				}
			} catch (Exception e) {
			}
		}
		return _theBrowser;
	}
	
	private static void setInputManagerWindowRoutines()	{
		InputManager manager = EcosystemManager.getInputManager();
		
	    // Refresh the layout when the window resizes
		manager.addWindowEventListener(new WindowEventListener() {
			@Override
			public void onWindowEvent(WindowEventType type)
			{
				if (type != WindowEventType.WINDOW_RESIZED) {
					return;
				}
				DisplayController.refreshWindowSize();
				FrameIO.RefreshCacheImages();
				for (Frame frame : DisplayController.getFrames()) {
					if (frame != null) {
						ItemUtils.Justify(frame);
						frame.refreshSize();
					}
				}
				DisplayController.requestRefresh(false);
			}
		});
		
		manager.addWindowEventListener(new WindowEventListener() {
			@Override
			public void onWindowEvent(WindowEventType type)
			{
				if (type != WindowEventType.MOUSE_EXITED_WINDOW) {
					return;
				}
				StandardGestureActions.mouseExitedWindow();
			}
		});
		
		manager.addWindowEventListener(new WindowEventListener() {
			@Override
			public void onWindowEvent(WindowEventType type)
			{
				if (type != WindowEventType.MOUSE_ENTERED_WINDOW) {
					return;
				}
				StandardGestureActions.mouseEnteredWindow();
			}
		});
		
		manager.addWindowEventListener(new WindowEventListener() {
			@Override
			public void onWindowEvent(WindowEventType type)
			{
				if (type != WindowEventType.WINDOW_CLOSED) {
					return;
				}
				if (Browser._theBrowser != null) {
					Browser._theBrowser.exit();
				}
			}
		});
	}

	/**
	 * @return The user's profile frame.
	 */
	public static Frame loadInitialProfiles()
	{
		String defaultProfileName = UserSettings.DEFAULT_PROFILE_NAME;
		String userName = System.getProperty("user.name");

		Frame defaultProfile = loadProfile(defaultProfileName);
		Frame userProfile = loadProfile(userName);
		
		MessageBay.warningMessages(FrameUtils.ParseProfile(defaultProfile));
		
		// Save the cursor if the defaultProfile had a custom cursor
		Collection<Item> cursor = null;
		if(FreeItems.hasCursor()) {
			cursor = new ArrayList<Item>();
			cursor.addAll(FreeItems.getCursor());
		}
		
		//MessageBay.warningMessages(FrameUtils.ParseProfile(userProfile));
		
		if (cursor != null && !FreeItems.hasCursor()) {
			FreeItems.setCursor(cursor);
		}
		
		FrameUtils.ParseProfile(userProfile);
		String proFileName = userProfile.getFramesetName();
		UserSettings.ProfileName.set(proFileName);
		
		return userProfile;
	}

	protected static Frame loadProfile(String userName)	{
		Frame profile = FrameIO.LoadProfile(userName);
		
		if (profile == null) {
			try {
				profile = FrameIO.CreateNewProfile(userName, null, null);
			} catch (Exception e) {
				// TODO tell the user that there was a problem creating the
				// profile frame and close nicely
				e.printStackTrace();
				assert (false);
			}
		}
		return profile;
	}

	public static String getStartFrame() {
		return _startFrame;
	}

	public static void setStartFrame(String _startFrame) {
		Browser._startFrame = _startFrame;
	}
}