package com.igor.grapheditor;

import java.awt.Color;
import java.awt.Cursor;
import java.awt.Graphics;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;

import javax.swing.JColorChooser;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JPopupMenu;

public class GraphPanel extends JPanel implements MouseListener, MouseMotionListener, KeyListener{

	private static final long serialVersionUID = 1L;



	protected Graph graph;

	private int mouseX = 0;
	private int mouseY = 0;
	private boolean mouseButtonLeft = false;
	@SuppressWarnings("unused")
	private boolean mouseButtonRight = false;
	protected int mouseCursor = Cursor.HAND_CURSOR;

	protected Node nodeUnderCursor = null;
	protected Edge edgeUnderCursor = null;
	protected Node createEdgeFrom = null;

	public GraphPanel() {
		addMouseListener(this);
		addMouseMotionListener(this);
		addKeyListener(this);
	    setFocusable(true);
	    requestFocus();
	}

	public Graph getGraph(){
		return this.graph;
	}

	public void setGraph(Graph graph) {
		this.graph = graph;
		this.nodeUnderCursor = null;
		this.edgeUnderCursor = null;
		this.createEdgeFrom = null;
		this.setCursor(Cursor.getDefaultCursor());
		this.repaint();
	}

	private Node findNode(int mx, int my) {
		for(Node node : graph.getNodes()) {
			if(node.isMouseOver(mx,my)) {
				return node;
			}
		}
		return null;
	}

	private Node findNode(MouseEvent event) {
		return findNode(event.getX(), event.getY());
	}

	private Edge findEdge(int mx, int my) {
		for(Edge edge : graph.getEdges()) {
			if(edge.isMouseOver(mx, my)) {
				return edge;
			}
		}
		return null;
	}

	private Edge findEdge(MouseEvent event) {
		return findEdge(event.getX(), event.getY());
	}

    protected void setMouseCursor(MouseEvent event) {
        this.nodeUnderCursor = this.findNode(event);
        this.edgeUnderCursor = this.findEdge(event);
        this.mouseCursor = this.nodeUnderCursor != null ? 12 : (this.createEdgeFrom != null ? 3 : (this.edgeUnderCursor != null ? 1 : (this.mouseButtonLeft ? 13 : 0)));
        this.setCursor(Cursor.getPredefinedCursor(this.mouseCursor));
        this.mouseX = event.getX();
        this.mouseY = event.getY();
    }

    protected void setMouseCursor(int mx, int my) {
        this.nodeUnderCursor = this.findNode(mx, my);
        this.edgeUnderCursor = this.findEdge(mx, my);
        this.mouseCursor = this.nodeUnderCursor != null ? 12 : (this.createEdgeFrom != null ? 3 : (this.edgeUnderCursor != null ? 1 : (this.mouseButtonLeft ? 13 : 0)));
        this.setCursor(Cursor.getPredefinedCursor(this.mouseCursor));
        this.mouseX = mx;
        this.mouseY = my;
    }

	private void moveNode(int dx, int dy, Node node) {
		node.setX(node.getX()+dx);
		node.setY(node.getY()+dy);
	}

	private void moveAllNodes(int dx, int dy) {
		for(Node node : graph.getNodes()) {
			moveNode(dx, dy, node);
		}
		repaint();
	}

	private void moveEdge(int dx, int dy, Edge edge) {
		this.moveNode(dx, dy, edge.getFrom());
		this.moveNode(dx, dy, edge.getTo());
	}

	@Override
	protected void paintComponent(Graphics g) {
		super.paintComponent(g);
		if(graph == null) return;
		graph.draw(g);
	}

	@Override
	public void mouseClicked(MouseEvent event){
	    this.setMouseCursor(event);
        if (event.getButton() == 1) {
            if (this.createEdgeFrom != null && this.nodeUnderCursor != null && this.nodeUnderCursor != this.createEdgeFrom) {
                this.graph.addNewEdge(this.createEdgeFrom, this.nodeUnderCursor);
                this.repaint();
            }
            this.createEdgeFrom = null;
        }
        this.setMouseCursor(event);
	}

	@Override
	public void mouseEntered(MouseEvent event){

	}

	@Override
	public void mouseExited(MouseEvent event){

	}

	@Override
	public void mousePressed(MouseEvent event){
		if(event.getButton() == 1) mouseButtonLeft = true;
		if(event.getButton() == 3) mouseButtonRight = true;
		setMouseCursor(event);
	}

	@Override
	public void mouseReleased(MouseEvent event){
		if(event.getButton() == 1) mouseButtonLeft = false;
		setMouseCursor(event);
		if(event.getButton() == 1)
		{

		}
		if(event.getButton() == 3) mouseButtonRight= false;
		setMouseCursor(event);
		if(event.getButton() == 3) {
			if(nodeUnderCursor != null) {
				createPopupMenu(event, nodeUnderCursor);
			}else if(edgeUnderCursor != null) {
				createPopupMenu(event, edgeUnderCursor);
			}else {
				createPopupMenu(event);
			}
		}
	}


	@Override
	public void mouseDragged(MouseEvent event) {
		if(mouseButtonLeft) {
			if(nodeUnderCursor != null) {
				moveNode(event.getX()-mouseX, event.getY()-mouseY, nodeUnderCursor);
			}else if (this.edgeUnderCursor != null) {
				this.moveEdge(event.getX() - this.mouseX, event.getY() - this.mouseY, this.edgeUnderCursor);
			}
                else {
				moveAllNodes(event.getX() - mouseX, event.getY() - mouseY);
			}
		}
		mouseX = event.getX();
		mouseY = event.getY();
		repaint();
	}

	@Override
	public void mouseMoved(MouseEvent event) {
		setMouseCursor(event);
	}

	@Override
	public void keyPressed(KeyEvent event) {
		{
			int dist;
			if (event.isShiftDown()) dist = 10;
			else dist = 1;
			switch(event.getKeyCode()) {
			case KeyEvent.VK_LEFT:
				moveAllNodes(-dist, 0);
				break;
			case KeyEvent.VK_RIGHT:
				moveAllNodes(dist, 0);
				break;
			case KeyEvent.VK_UP:
				moveAllNodes(0, -dist);
				break;
			case KeyEvent.VK_DOWN:
				moveAllNodes(0, dist);
				break;
			case KeyEvent.VK_DELETE:
				if(nodeUnderCursor != null) {
					graph.removeNode(nodeUnderCursor);
					nodeUnderCursor = null;
				}
				break;
			}
			repaint();
		}

	}

	@Override
	public void keyReleased(KeyEvent event) {
	}

	@Override
	public void keyTyped(KeyEvent event) {
		char znak=event.getKeyChar();
		if (nodeUnderCursor!=null){
		switch (znak) {
		case 'r':
			nodeUnderCursor.setColor(Color.RED);
			break;
		case 'g':
			nodeUnderCursor.setColor(Color.GREEN);
			break;
		case 'b':
			nodeUnderCursor.setColor(Color.BLUE);
			break;
		case '+':
			int r = nodeUnderCursor.getR()+10;
			nodeUnderCursor.setR(r);
			break;
		case '-':
			r = nodeUnderCursor.getR()-10;
			if (r>=10) nodeUnderCursor.setR(r);
			break;
		}
		repaint();
		}
	}

	protected void createPopupMenu(MouseEvent event) {
        JMenuItem menuItem;
        JPopupMenu popup = new JPopupMenu();
        menuItem = new JMenuItem("Create new node");
		menuItem.addActionListener((action) -> {
			graph.addNode(new Node(event.getX(), event.getY()));
			repaint();
		});
		popup.add(menuItem);
        popup.show(event.getComponent(), event.getX(), event.getY());
    }

	protected void createPopupMenu(MouseEvent event, Node node) {
		JMenuItem menuItem;

		JPopupMenu popup = new JPopupMenu();
		menuItem = new JMenuItem("Change node color");
		menuItem.addActionListener((a) -> {
			Color newColor = JColorChooser.showDialog(this,"Choose Background Color", node.getColor());
				if (newColor!=null){
					node.setColor(newColor);
				}
				repaint();
			});
		popup.add(menuItem);

		menuItem = new JMenuItem("Remove this node");
		menuItem.addActionListener((action) -> {
				graph.removeNode(node);
				repaint();
		});
		popup.add(menuItem);

		menuItem = new JMenuItem("Create new edge from this node");
		menuItem.addActionListener((ac) -> {

				createEdgeFrom = node;
				mouseCursor = Cursor.WAIT_CURSOR;
		});
		popup.add(menuItem);

		menuItem = new JMenuItem("Change name of this node");
		menuItem.addActionListener((ac) -> {
			String name = (String)JOptionPane.showInputDialog(this, "Enter new name:", "Change node name", 3, null, null, node.getName());
            if (name != null) {
                node.setName(name);
            }
            this.repaint();
		});
		popup.add(menuItem);

		popup.show(event.getComponent(), event.getX(), event.getY());
	}

	protected void createPopupMenu(MouseEvent event, Edge edge) {
        JPopupMenu popup = new JPopupMenu();
        JMenuItem menuItem = new JMenuItem("Remove this edge");
        menuItem.addActionListener(a -> {
            this.graph.removeEdge(edge);
            this.repaint();
        });
        popup.add(menuItem);

        menuItem = new JMenuItem("Change edge color");
		menuItem.addActionListener((a) -> {
			Color newColor = JColorChooser.showDialog(this,"Choose Background Color", edge.getColor());
				if (newColor!=null){
					edge.setColor(newColor);
				}
				repaint();
			});
		popup.add(menuItem);
        popup.show(event.getComponent(), event.getX(), event.getY());
    }

}