package ui.view;

import classes.*;
import classes.comparator.UnitGraphPointComperator;
import interfaces.GraphEditable;
import interfaces.GraphEditable.Graphtype;
import interfaces.IGraphedElement;
import sun.reflect.generics.reflectiveObjects.NotImplementedException;
import ui.controller.Control;
import ui.controller.SingletonControl;
import ui.model.Model;

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.Path2D;
import java.awt.geom.Point2D;
import java.util.ArrayList;
import java.util.LinkedList;
import java.util.ListIterator;

/**
 * This Class represents a Graph where the User can model the behavior of
 * elements and switches over time.
 *
 * @author Tom Troppmann
 */
public class UnitGraph extends JPanel implements MouseListener, MouseMotionListener, ComponentListener {

    private static final long serialVersionUID = 1L;
	
	
	// Normal Settings
	private int border = 4;
	private int clickThreshholdSquared = 25;
	
	// Display Settings
	/**
	 * The size of a dot in the graph.
	 * It should be at least 1.
	 * */
	int dotSize = 8;
	/** The Color of a dot in the graph. */
	Color dotColor = Color.blue;
	Color editDotColor = new Color(255, 119, 0);
	
	//Intern Variables
	//TODO: JavaDoc
	private LinkedList<UnitGraphPoint> actualGraphPoints = new LinkedList<UnitGraphPoint>();
	private Graphtype actualGraphType;
	private GraphEditable actualElement;
	Position editPosition;
	boolean editMode = false;
	private enum pointType {Normal, StartPoint, EndPoint};
	pointType editPoint = pointType.Normal;
	
	//Maybe Needed
	private Model model;
	private Control controller;
	
	
	private int widthWithBorder, heightWithBorder;
	
	
	
	
	
	
    /**
     * Constructor.
     *
     * @param model   the Model
     * @param control the Controller
     */
    public UnitGraph(final Model model, Control control) {
        setCursor(Cursor.getPredefinedCursor(Cursor.CROSSHAIR_CURSOR));
        this.controller = control;
        this.model = model;
        this.setBackground(Color.WHITE);

        this.addMouseListener(this);
        this.addMouseMotionListener(this);
        this.addComponentListener(this);
    }

    /**
     * Paints all Components on the Canvas.
     *
     * @param g Graphics
     */
    public void paintComponent(Graphics g) {
        super.paintComponent(g);
        Graphics2D g2D = (Graphics2D) g;
        drawGrid(g2D);
        g2D.setColor(Color.BLACK);
        g2D.setRenderingHints(new RenderingHints(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON));
        g2D.setStroke(new BasicStroke(2));
        drawUnitGraph(g2D);
        g2D.setColor(dotColor);
        if(editMode)
        {
        	drawUnitGraphPointsReleased(g2D);
        }else
        {
        	 drawUnitGraphPoints(g2D);
        }
        g2D.setColor(dotColor);
        g2D.setStroke(new BasicStroke(1));
        drawCurrentIterartionLine(g2D);
    }

	private void drawGrid(Graphics2D g2D) {
        g2D.setStroke(new BasicStroke(1));
        g2D.setColor(Color.lightGray);
        int amountOfLines = 10;
        int width = widthWithBorder + 2 * border;
        int height = heightWithBorder;
        for(int i = 0; i<=amountOfLines; i++)
        {
        	int linehieght = (int) (((double)i/ (double) amountOfLines) * (double) height) + border;
        	g2D.drawLine(0, linehieght, width, linehieght);
        }
	}
    
    private void drawCurrentIterartionLine(Graphics2D g)
    {
    	int cur = model.getCurIteration();
    	int max = model.getIterations();
    	double where = ((double) cur)/((double) max - 1);
    	Position oben = new Position(border + (int)(where * widthWithBorder), 0);
    	Position unten = new Position(border + (int)(where * widthWithBorder), 2 * border + heightWithBorder);
    	drawLine(g,oben,unten);
    }
    
    private void drawLine(Graphics2D g, Position start, Position end)
    {
    	Path2D.Double path = new Path2D.Double();
    	path.moveTo(start.x, start.y);
    	path.lineTo(end.x, end.y);
    	g.draw(path);
    }
    
    private Path2D.Double initBezier(Position start) {
    	//Good Source for basic understanding for Bezier Curves
        //http://www.theappguruz.com/blog/bezier-curve-in-games
    	Path2D.Double path = new Path2D.Double();
    	path.moveTo(start.x, start.y);
		return path;
    }
    private void curveTo(Path2D.Double path, Position actual, Position target) {
         double mitte = (actual.x + target.x)* 0.5;
         path.curveTo(mitte, actual.y, mitte, target.y, target.x, target.y);
    }
    private void drawDot(Graphics2D g, Position p)
    {    	
    	g.fillOval(p.x -dotSize/2, p.y-dotSize/2, dotSize, dotSize);
    }
    private void drawUnitGraph(Graphics2D g) {
    	switch(actualGraphType) {
		case boolGraph:
			if(editMode)
				drawBoolGraphWithEditPosition(g);
			else
				drawBoolGraph(g);
			break;
		case doubleGraph:
			if(editMode)
				drawDoubleGraphWithEditPosition(g);
			else
				drawDoubleGraph(g);
			break;
		default:
			throw new UnsupportedOperationException();
    	}
    }
    private void drawUnitGraphPoints(Graphics2D g) {
    	g.setColor(dotColor);
    	for(UnitGraphPoint p : actualGraphPoints){
    		drawDot(g, p.displayedPosition);
    	}
    }
    
	private void saveGraph() {
		LinkedList<Point2D.Double> actual = actualElement.getStateGraph();
		actual.clear();
		for(UnitGraphPoint p: actualGraphPoints)
		{
			actual.add(p.getPoint());
		}
		actualElement.sampleGraph();
	}
    private void drawUnitGraphPointsReleased(Graphics2D g) {
    	drawUnitGraphPoints(g);
    	g.setColor(editDotColor);
		drawDot(g, editPosition);
    }
    
    private void drawBoolGraph(Graphics2D g) {
    	System.out.println("DoImplement");
    	if(actualGraphPoints.size() <= 1) return;
    	LinkedList<Position> cornerPoints =  new LinkedList<Position>();
     	ListIterator<UnitGraphPoint> iter = actualGraphPoints.listIterator();
     	Position actual = actualGraphPoints.getFirst().displayedPosition;
     	Path2D.Double path = new Path2D.Double();
     	path.moveTo(actual.x, actual.y);
     	while (iter.hasNext())
    	{
    		Position target = iter.next().displayedPosition;
    		//BooleanConnection
    		path.lineTo(target.x, actual.y); //line to corner
    		cornerPoints.add(new Position(target.x, actual.y)); //save corner
    		path.lineTo(target.x, target.y); //line to next Point
    		
    		actual = target;
    	}
     	g.draw(path);
     	//Draw the Points on the Corner that dont exist in Data but should be visual
     	g.setColor(dotColor);
     	for(Position p: cornerPoints)
     	{
     		drawDot(g, p);
     	}
     	
    }
    
    private void drawBoolGraphWithEditPosition(Graphics2D g) {
    	LinkedList<Position> before = new LinkedList<Position>();
     	LinkedList<Position> after = new LinkedList<Position>();
     	for(UnitGraphPoint p: actualGraphPoints)
     	{
     		if(p.displayedPosition.x < editPosition.x)
     			before.add(p.displayedPosition);
     		else
     			after.add(p.displayedPosition);
     	}    	
     	g.setColor(Color.BLACK);
     	drawBoolGraphFromList(g, before);
     	g.setColor(Color.BLACK);
     	drawBoolGraphFromList(g, after);
     	//EditGraph
     	LinkedList<Position> middle = new LinkedList<Position>();
     	if(!before.isEmpty()) middle.add(before.getLast());
     	middle.add(editPosition);
    	if(!after.isEmpty()) middle.add(after.getFirst());
    	
    	g.setColor(editDotColor);
    	drawBoolGraphFromList(g, middle);
    	drawSnappingHint(g);
    }
    
    private void drawSnappingHint(Graphics2D g)
    {
    	//ColorHint
    	g.setColor(Color.RED);
    	//Threshhold Line
    	final float dash1[] = {10.0f};
        final BasicStroke dashed =new BasicStroke(2.0f, BasicStroke.CAP_BUTT, BasicStroke.JOIN_MITER, 10.0f, dash1, 0.0f);
        g.setStroke(dashed);
        
        
        int halfheight =  border + heightWithBorder / 2;
        g.drawLine(0, halfheight , widthWithBorder + 2 * border, halfheight);
        //Threshhold Text
        g.drawString("Snapping Threshold", 10, halfheight - 2);
    }
    
    
    
    
	private void drawBoolGraphFromList(Graphics2D g, LinkedList<Position> list) {
		if(list.size() <= 1) return;
     	ListIterator<Position> iter = list.listIterator();
      	LinkedList<Position> cornerPoints =  new LinkedList<Position>();
     	Position actual = list.getFirst();
     	Path2D.Double path = new Path2D.Double();
     	path.moveTo(actual.x, actual.y);
     	while (iter.hasNext())
    	{
    		Position target = iter.next();
    		//BooleanConnection
    		path.lineTo(target.x, actual.y); //line to corner
    		cornerPoints.add(new Position(target.x, actual.y)); //save corner
    		path.lineTo(target.x, target.y); //line to next Point
    		actual = target;
    	}
     	g.draw(path);
    	g.setColor(dotColor);
     	for(Position p: cornerPoints)
     	{
     		drawDot(g, p);
     	}
	}
    
    
    private void drawDoubleGraph(Graphics2D g) {
    	if(actualGraphPoints.isEmpty()) throw new IndexOutOfBoundsException("A Graph Without Points is not supportet jet");
    	ListIterator<UnitGraphPoint> iter = actualGraphPoints.listIterator();
    	Position actual = iter.next().displayedPosition;
    	Path2D.Double path = this.initBezier(actual);
    	while (iter.hasNext())
    	{
    		Position target = iter.next().displayedPosition;
    		this.curveTo(path, actual, target);
    		actual = target;
    	}
    	g.draw(path);
    	
    }
    private void drawDoubleGraphWithEditPosition(Graphics2D g) {
     	LinkedList<Position> before = new LinkedList<Position>();
     	LinkedList<Position> after = new LinkedList<Position>();
     	for(UnitGraphPoint p: actualGraphPoints)
     	{
     		if(p.displayedPosition.x < editPosition.x)
     			before.add(p.displayedPosition);
     		else
     			after.add(p.displayedPosition);
     	}    	
     	drawUnitGraphFromList(g, before);
     	drawUnitGraphFromList(g, after);
     	//EditGraph
     	LinkedList<Position> middle = new LinkedList<Position>();
     	if(!before.isEmpty()) middle.add(before.getLast());
     	middle.add(editPosition);
    	if(!after.isEmpty()) middle.add(after.getFirst());
    	
    	g.setColor(editDotColor);
    	drawUnitGraphFromList(g, middle);
    }

	private void drawUnitGraphFromList(Graphics2D g, LinkedList<Position> list) {
		if(list.size() <= 1) return;
     	ListIterator<Position> iter = list.listIterator();
     	Position actual = list.getFirst();
     	Path2D.Double path = this.initBezier(actual);
     	while (iter.hasNext())
    	{
    		Position target = iter.next();
    		curveTo(path, actual, target);
    		actual = target;
    	}
     	g.draw(path);
	}
  
    
    
    private void updateRepresentativePositions()
    {
    	for(UnitGraphPoint p : actualGraphPoints) {
    		p.calcDisplayedPosition(border, widthWithBorder, heightWithBorder);
    	}
    }
    
    private void overrideUnitGraph(LinkedList<Point2D.Double> stateCurve) {
    	actualGraphPoints.clear();
    	for(Point2D.Double p: stateCurve){
    		actualGraphPoints.add(new UnitGraphPoint(p));
    	}
    	updateRepresentativePositions();
    }
    private void calculateWidthHeight()
    {
    	widthWithBorder = this.getWidth() - 2 * border;
    	heightWithBorder = this.getHeight() - 2 * border;
    }
    
    public void initNewElement(GraphEditable element)
    {
    	overrideUnitGraph(element.getStateGraph());
    	actualGraphType = element.getGraphType();
    	actualElement = element;
    	repaint();
    }
    
    
    private void removePointNearPosition(Position mPosition) {
    	ListIterator<UnitGraphPoint> iter = actualGraphPoints.listIterator();
    	while (iter.hasNext())
    	{
    		if(near(mPosition,iter.next().displayedPosition))
    		{
    			iter.remove();
    			break;
    		}
    	}
    }
    
    private void  detectStartEndPoint(Position mPosition)
    {
    	UnitGraphPoint first = actualGraphPoints.getFirst();
    	UnitGraphPoint last = actualGraphPoints.getLast();
    	if(near(mPosition, first.displayedPosition)) editPoint = pointType.StartPoint;
    	else if(near(mPosition, last.displayedPosition))  editPoint = pointType.EndPoint;
    	else editPoint = pointType.Normal;
    }

	private boolean near(Position actual, Position target) {
		switch(actualGraphType)
		{
		case boolGraph: //Distance only with X 
			int xDis = target.x - actual.x;
			return xDis * xDis  < clickThreshholdSquared;
		case doubleGraph:
			return actual.squareDistance(target) < clickThreshholdSquared;
		default:
			return false;
		}	
	}
    
    private void updateEditPointPosition(Position newPosition) {
    	//make it in the bounds of the UnitGraph no Point out of the Border
    	Position currentPosition = setInBounds(newPosition);
    	if(editPoint != pointType.Normal) attachToBorder(currentPosition);
    	if(actualGraphType == Graphtype.boolGraph) snapBoolean(currentPosition);
    	this.editPosition = currentPosition;
    }
    
	private Position setInBounds(Position p) {
		p.clampX(border, border + widthWithBorder);
		p.clampY(border, border + heightWithBorder);
		return p;
	}
    
	
	private Position snapBoolean(Position p)
	{
		if (p.y < border + heightWithBorder / 2) {
			p.y = border;
		} else {
			p.y = border + heightWithBorder;
		}
		return p;
	}
	
	
	private Point.Double getBezierPoint(double t, Point.Double p0, Point.Double p1,Point.Double p2,Point.Double p3) {
    	/*
    	 * Calculate Beziér:
    	 * B(t) = (1-t)^3 * P0 + 3*(1-t)^2 * t * P1 + 3*(1-t)*t^2 * P2 + t^3 * P3 , 0 < t < 1
    	 * 
    	 * Source: //http://www.theappguruz.com/blog/bezier-curve-in-games
    	 */
		Point.Double bezier = new Point.Double();
		double OneSubT =  1-t;
		double OneSubT2 = Math.pow(OneSubT, 2);
		double OneSubT3 = Math.pow(OneSubT, 3);
		double t2 = Math.pow(t , 2);
		double t3 = Math.pow(t , 3);
	
		bezier.x = OneSubT3 * p0.x + 3 * OneSubT2 * t * p1.x + 3 * OneSubT * t2 * p2.x + t3 * p3.x;
		bezier.y = OneSubT3 * p0.y + 3 * OneSubT2 * t * p1.y + 3 * OneSubT * t2 * p2.y + t3 * p3.y;
		return bezier;
		
	}
	private double getYBetweenTwoPoints(double t, Point.Double start, Point.Double end) {
		
	    double mitte = (start.x + end.x)* 0.5;
	    Point.Double bezier = getBezierPoint(t, start, new Point.Double(mitte, start.y), new Point.Double(mitte, end.y), end);
		return bezier.y;
	}
	
	private float[] sampleGraph(int sampleLength)
	{		
		ListIterator<UnitGraphPoint> iter = actualGraphPoints.listIterator();
		Point.Double before = iter.next().getPoint();
		Point.Double after = iter.next().getPoint();
		float [] sampleCurve = new float[sampleLength];	
		for(int i = 0; i<sampleLength ; i++)
		{
			double graphX = (double)i / (double) (sampleLength - 1); //from 0.0 to 1.0
			if(graphX > after.x)
			{
				before = after;
				after = iter.next().getPoint();
			}
			//inverseLerp(valueBetween, min, max) (valueBetween - min) / (max - min)
			// e.g. old.x = 0.4, actual.x = 0.8 and graphX = 0.6 then t is 0.5
			double t = (after.x -before.x > 0)? (graphX - before.x) / (after.x -before.x) : 0.0;			
			sampleCurve[i] = (float) getYBetweenTwoPoints(t, before, after);
		}
		return sampleCurve;
	}
	
	
	private Position attachToBorder(Position p)
	{
		switch(editPoint)
		{
		case StartPoint:
			p.x = border;
			break;
		case EndPoint:
			p.x = border + widthWithBorder;
			break;
		default:
			break;
		}
		return p;
	}
    private void insertNewGraphPoint(Position pos)
    {
    	System.out.println("insertNewGraphPoint");
    	setInBounds(pos);
    	ListIterator<UnitGraphPoint> iter2 = actualGraphPoints.listIterator();
    	while (iter2.hasNext())
    	{
    		Position tempPosition = iter2.next().displayedPosition;
    		if(pos.x <= tempPosition.x)
    		{
    			//previous to go back a position to make the new point before the the Position with greater X
    			iter2.previous();
    			iter2.add(generateUnitGraphPoint(pos));
    			break;
    		}
    	}
    	if(!iter2.hasNext()) //if behind last point
    	{
    		iter2.add(generateUnitGraphPoint(pos));
    	}
    }

	private UnitGraphPoint generateUnitGraphPoint(Position pos) {
		UnitGraphPoint temp = new UnitGraphPoint((double) (pos.x - border) / (double) widthWithBorder,
				1 - (double) (pos.y - border) / (double) heightWithBorder, true);
		temp.displayedPosition = pos;
		return temp;
	}

    
	@Override
    public void mouseDragged(MouseEvent e) {
    	System.out.println("MouseDragged");
    	updateEditPointPosition(new Position(e.getPoint()));
    	repaint();
    }

    @Override
    public void mouseMoved(MouseEvent e) {
    }

    @Override
    public void mouseClicked(MouseEvent e) {
    }

    @Override
    public void mouseEntered(MouseEvent e) {
    }

    @Override
    public void mouseExited(MouseEvent e) {
    }

    @Override
    public void mousePressed(MouseEvent e) {
		System.out.println("mousePressed");
		Position mPosition = new Position(e.getPoint());
		if (e.getButton() == MouseEvent.BUTTON3) {
			// RightMouseButtonEvent
			detectStartEndPoint(mPosition);
			if (editPoint == pointType.Normal) {
				removePointNearPosition(mPosition);
				repaint();
			}
			editMode = false;

		} else if (e.getButton() == MouseEvent.BUTTON1) {
			// LeftMouseButtonEvent
			detectStartEndPoint(mPosition);
			removePointNearPosition(mPosition);
			updateEditPointPosition(mPosition);
			editMode = true;
			repaint();
		}
	}

    @Override
    public void mouseReleased(MouseEvent e) {
    	System.out.println("mouseReleased");
    	if(editMode)
    	{
    		this.insertNewGraphPoint(editPosition);
    		editMode = false;
    		repaint();
    	}
    	saveGraph();
    }

    /**
     * When the Component is Resized.
     *
     * @param e ComponentEvent
     */
    public void componentResized(ComponentEvent e) {
    	System.out.println("componentResized");
    	calculateWidthHeight();
    	updateRepresentativePositions();
        repaint();
    }

    @Override
    public void componentHidden(ComponentEvent e) {
    }

    @Override
    public void componentMoved(ComponentEvent e) {

    }

    @Override
    public void componentShown(ComponentEvent e) {
    }

    public void reset() {
       	System.out.println("reset");
       	if(this.actualElement != null) {
       		actualElement.reset();
       		overrideUnitGraph(actualElement.getStateGraph());
       		repaint();
       	}
       	
    }

    public void update(ArrayList<AbstractCpsObject> obj) {
    	System.out.println("update");
    }

	public void setStretching(boolean selected) {
		System.out.println("setStretching");
	}

	public void setLocalPeriod(int localLength) {
		System.out.println("setLocalPeriod");
	}

	public void repaintGraph(AbstractCpsObject cps) {
		// TODO Auto-generated method stub
		System.out.println("repaintGraph");
	}
   
    

}