/*
 * The MIT License (MIT)
 * 
 * Copyright (c) 2015 Camil Staps <info@camilstaps.nl>
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
package com.camilstaps.mandelbrot;

import java.awt.Color;
import java.awt.Graphics;
import java.awt.event.InputEvent;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
import javax.swing.JFrame;

/**
 * A frame in which zooming is possible
 * @author Camil Staps, s4498062
 */
public class ZoomFrame extends JFrame implements MouseListener, MouseMotionListener {
    
    private MandelbrotView mandelbrotView;
    private MandelbrotTextFields mandelbrotTextFields;
    
    private Graphics graphics;
    
    private int start_x, start_y, old_x, old_y;
    private boolean dragging = false;
    
    public ZoomFrame(String s) {
        super(s);
        addMouseListener(this);
        addMouseMotionListener(this);
    }
    
    public void setMandelbrotView(MandelbrotView mv) {
        mandelbrotView = mv;
    }
    
    public void setMandelbrotTextFields(MandelbrotTextFields mtf) {
        mandelbrotTextFields = mtf;
    }

    @Override
    public void mouseClicked(MouseEvent me) {}

    /**
     * Save the coordinates
     * @param me 
     */
    @Override
    public void mousePressed(MouseEvent me) {
        old_x = start_x = me.getX();
        old_y = start_y = me.getY();
    }

    /**
     * On shift-click, zoom out.
     * On click, zoom in.
     * On drag, zoom the box.
     * @param me 
     */
    @Override
    public void mouseReleased(MouseEvent me) {
        if (me.getX() == start_x && me.getY() == start_y) {
            if ((me.getModifiers() & InputEvent.SHIFT_MASK) != 0) {
                zoomOut(me);
            } else {
                zoomIn(me);
            }
        } else {
            zoomBox(me);
        }
            
        mandelbrotView.redraw();
        
        dragging = false;
    }
    
    /**
     * Zoom in with factor 2
     * @param me 
     */
    private void zoomIn(MouseEvent me) {
        if (mandelbrotView == null || mandelbrotTextFields == null)
            return;

        mandelbrotTextFields.setCenterX(mandelbrotView.getX(me.getX()));
        mandelbrotTextFields.setCenterY(mandelbrotView.getY(me.getY()));

        mandelbrotTextFields.setScale(mandelbrotTextFields.getScale() * 2);
    }
    
    /**
     * Zoom out with factor 2
     * @param me 
     */
    private void zoomOut(MouseEvent me) {
        if (mandelbrotView == null || mandelbrotTextFields == null)
            return;

        mandelbrotTextFields.setCenterX(mandelbrotView.getX(me.getX()));
        mandelbrotTextFields.setCenterY(mandelbrotView.getY(me.getY()));

        mandelbrotTextFields.setScale(mandelbrotTextFields.getScale() / 2);
    }
    
    /**
     * Zoom to the selected box.
     * Intentionally chose to let the user only select squares, otherwise it's too easy to mess up the scale
     * @param me 
     */
    private void zoomBox(MouseEvent me) {
        double center_x = (mandelbrotView.getX(me.getX())
                - mandelbrotView.getX(start_x)) / 2
                + mandelbrotView.getX(start_x);
        double center_y = (mandelbrotView.getY(me.getY())
                - mandelbrotView.getY(start_y)) / 2
                + mandelbrotView.getY(start_y);

        mandelbrotTextFields.setCenterX(center_x);
        mandelbrotTextFields.setCenterY(center_y);

        double scale = mandelbrotTextFields.getScale()
                / (me.getX() - start_x)
                * getWidth();

        mandelbrotTextFields.setScale(scale);
    }

    @Override
    public void mouseEntered(MouseEvent me) {}

    @Override
    public void mouseExited(MouseEvent me) {}

    /**
     * Erase the old box, draw the new box
     * @param me 
     */
    @Override
    public void mouseDragged(MouseEvent me) {
        Graphics g = getSafeGraphics();
        if (g != null) {
            if (dragging) {
                eraseZoombox();
            }
            g.drawRect(start_x, start_y, me.getX() - start_x, me.getX() - start_x);
            old_y = old_x = me.getX();
            dragging = true;
        }
    }
    
    /**
     * Semi-singleton construction for graphics
     * @return 
     */
    private Graphics getSafeGraphics() {
        if (graphics == null) {
            graphics = getGraphics();
            graphics.setXORMode(Color.white);
        }
        return graphics;
    }
    
    /**
     * Erase the old zoombox if it exists
     */
    private void eraseZoombox() {
        if (start_x < 0 || start_y < 0 || old_x < 0 || old_y < 0)
            return;
        Graphics g = getSafeGraphics();
        if (g != null)
            g.drawRect(start_x, start_y, old_x - start_x, old_y - start_x);
    }

    @Override
    public void mouseMoved(MouseEvent me) {}
    
    /**
     * Interface to get and set user input
     */
    public interface MandelbrotTextFields {
        
        /**
         * Set the center X
         * @param x 
         */
        public void setCenterX(double x);
        
        /**
         * Set the center Y
         * @param y 
         */
        public void setCenterY(double y);
        
        /**
         * Get the scale factor
         * @return 
         */
        public double getScale();
        
        /**
         * Set the scale factor
         * @param scale 
         */
        public void setScale(double scale);
        
        /**
         * Set the max amount of iterations for the mandel function
         * @param repetitions 
         */
        public void setRepetitions(int repetitions);
    }
    
}