package jcgp.gui;

import javafx.application.Application;
import javafx.application.Platform;
import javafx.concurrent.Service;
import javafx.concurrent.Task;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.input.MouseEvent;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.Pane;
import javafx.stage.Stage;
import javafx.stage.WindowEvent;
import jcgp.JCGP;
import jcgp.backend.modules.problem.TestCaseProblem.TestCase;
import jcgp.gui.console.GUIConsole;
import jcgp.gui.dragresize.HorizontalDragResize;
import jcgp.gui.dragresize.VerticalDragResize;
import jcgp.gui.population.FunctionSelector;
import jcgp.gui.population.GUINode;
import jcgp.gui.population.PopulationPane;
import jcgp.gui.settings.SettingsPane;

/**
 * Main class for the graphical user interface (GUI)
 * 
 * 
 * @author Eduardo Pedroni
 *
 */
public class GUI extends Application {
	
	/* Colours */
	public static final String NEUTRAL_COLOUR = "#FFFFFF";
	public static final String HARD_HIGHLIGHT_COLOUR = "#5496FF";
	public static final String MEDIUM_HIGHLIGHT_COLOUR = "#75BAFF";
	public static final String SOFT_HIGHLIGHT_COLOUR = "#C7DFFF";
	
	public static final String GOOD_SELECTION_COLOUR = "#38C25B";
	public static final String NEUTRAL_SELECTION_COLOUR = "#FFEF73";
	public static final String BAD_SELECTION_COLOUR = "#FF5C5C";
	
	/* Sizes and distances */
    public static final double RESIZE_MARGIN = 5.0;
    public static final double SETTINGS_MIN_WIDTH = 200;
    public static final double CONSOLE_MIN_HEIGHT = 100;
    
	private final JCGP jcgp;
	
	private Stage stage;
	
	private final FunctionSelector functionSelector;
	
	private PopulationPane populationPane;
	
	private GUIConsole console;
	
	private SettingsPane settingsPane;
	
	private boolean running = false;
	
	private final Object printLock = new Object();
	
	private Service<Void> cgpService;
	
	private Runnable consoleFlush;
	
	public static void main(String[] args) {
		launch();
	}
	
	public GUI() {
		jcgp = new JCGP();
		functionSelector = new FunctionSelector(jcgp.getResources().getFunctionSet());
		
		consoleFlush = new Runnable() {
			@Override
			public void run() {
				synchronized(printLock) {
					console.flush();
					printLock.notifyAll();
				}
			}
		};
		
		cgpService = new Service<Void> () {
			@Override
			protected Task<Void> createTask() {
				Task<Void> t = new Task<Void>() {
					@Override
					protected Void call() throws Exception {
						while (!isCancelled() && !jcgp.isFinished()) {
							synchronized (printLock) {
								Platform.runLater(consoleFlush);
								jcgp.nextGeneration();
								printLock.wait();
							}
						}
						if (jcgp.isFinished()) {
							Platform.runLater(new Runnable() {
								@Override
								public void run() {
									runningMode(false);
								}
							});
						}
						return null;
					}
				};
				return t;
			}
		};
	}
	
	@Override
	public void start(Stage primaryStage) throws Exception {
		console = new GUIConsole();
		jcgp.setConsole(console);
		stage = primaryStage;
		/*
		 * Instantiate the various GUI elements here. 
		 * 
		 * 
		 */
		BorderPane leftFrame = new BorderPane();
		BorderPane experimentLayer = new BorderPane();
		
		populationPane = new PopulationPane(this);
		
		settingsPane = new SettingsPane(this);
		settingsPane.maxWidthProperty().bind(experimentLayer.widthProperty());
		
		console.maxHeightProperty().bind(experimentLayer.heightProperty());
		
		HorizontalDragResize.makeDragResizable(settingsPane);
		VerticalDragResize.makeDragResizable(console);
		
		leftFrame.setCenter(populationPane);
		leftFrame.setBottom(console);
		
		experimentLayer.setCenter(leftFrame);
		experimentLayer.setRight(settingsPane);
		
		primaryStage.setTitle("JCGP");
		
		Pane sceneParent = new Pane();
		experimentLayer.prefHeightProperty().bind(sceneParent.heightProperty());
		experimentLayer.prefWidthProperty().bind(sceneParent.widthProperty());
		sceneParent.getChildren().addAll(experimentLayer, functionSelector);
		
		primaryStage.setScene(new Scene(sceneParent));
		primaryStage.setMinWidth(800);
		primaryStage.setMinHeight(600);
		primaryStage.show();
		
		primaryStage.setOnCloseRequest(new EventHandler<WindowEvent>() {
			@Override
			public void handle(WindowEvent event) {
				settingsPane.getTestCaseTable().close();
			}
		});
	}

	public void runPause() {
		if (!jcgp.isFinished() && settingsPane.areParametersValid()) {
			if (!running) {
				runningMode(true);
				cgpService.restart();
			} else {
				cgpService.cancel();
				runningMode(false);
			}
		}
	}
	
	public void step() {
		if (!running && !jcgp.isFinished() && settingsPane.areParametersValid()) {
			if (settingsPane.isResetRequired()) {
				reset();
			}
			populationPane.unlockOutputs();
			jcgp.nextGeneration();
			console.flush();
			
			populationPane.updateGenes();
			populationPane.relockOutputs();
			settingsPane.revalidateParameters();
			settingsPane.updateControls(false, jcgp.isFinished());
		}
	}
	
	public void reset() {
		if (!running && settingsPane.areParametersValid()) {
			setEvaluating(false);
			jcgp.reset();
			settingsPane.applyParameters();
			reDraw();
		}
	}
	
	public void reDraw() {
		populationPane.remakeTabs();
		settingsPane.revalidateParameters();
		settingsPane.updateControls(false, jcgp.isFinished());
		console.flush();
	}
	
	private void runningMode(boolean value) {		
		if (value) {
			populationPane.unlockOutputs();
			if (settingsPane.isResetRequired()) {
				reset();
			}
		} else {
			populationPane.updateGenes();
			populationPane.relockOutputs();
			settingsPane.revalidateParameters();
		}
		populationPane.setDisable(value);
		settingsPane.updateControls(value, jcgp.isFinished());
		
		running = value;
	}
	
	public void updateFunctionSelector() {
		functionSelector.remakeFunctions(jcgp.getResources().getFunctionSet());
	}
	
	public boolean isWorking() {
		return running;
	}

	public void bringFunctionSelector(MouseEvent event, GUINode node) {
		functionSelector.relocateAndShow(event, node);
	}

	public JCGP getExperiment() {
		return jcgp;
	}
	
	public void evaluateTestCase(TestCase<Object> testCase) {
		populationPane.evaluateTestCase(testCase);
	}

	public void hideGeneValues() {
		populationPane.hideValues();
	}

	public void setEvaluating(boolean value) {
		populationPane.setEvaluating(value);
	}

	public Stage getStage() {
		return stage;
	}
	
	public void flushConsole() {
		console.flush();
	}

	public int getChromosomeIndex() {
		return populationPane.getSelectionModel().getSelectedIndex();
	}
}