/*
 Copyright (C) 2012 Red Hat, Inc.

 This file is part of IcedTea.

IcedTea 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, version 2.

IcedTea 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
IcedTea; see the file COPYING. If not, write to the
Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA.

Linking this library statically or dynamically with other modules is making a
combined work based on this library. Thus, the terms and conditions of the GNU
General Public License cover the whole combination.

As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent modules, and
to copy and distribute the resulting executable under terms of your choice,
provided that you also meet, for each linked independent module, the terms and
conditions of the license of that module. An independent module is a module
which is not derived from or based on this library. If you modify this library,
you may extend this exception to your version of the library, but you are not
obligated to do so. If you do not wish to do so, delete this exception
statement from your version. */
package net.adoptopenjdk.icedteaweb.client.parts.splashscreen.parts.extensions;

import net.adoptopenjdk.icedteaweb.client.parts.splashscreen.impls.defaultsplashscreen2012.BasePainter;
import net.adoptopenjdk.icedteaweb.client.parts.splashscreen.impls.defaultsplashscreen2012.ErrorPainter;

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Polygon;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;

public class ChristmasExtension implements SplashExtension {

    @Override
    public Color getBackground() {
        return Color.black;
    }

    @Override
    public Color getTextColor() {
        return Color.DARK_GRAY;
    }

    @Override
    public Color getPluginTextColor() {
        return new Color(30, 30, 30);
    }

    ChristmasExtension() {
        this(0, 0);
    }
    private static final Random seed = new Random();
    private static final int average_star_width = 10; //stars will be 5-15
    private final int average_fall_speed = 4; //2-6
    private final int average_rotation_speed = 2; //1-3

    private class Star {

        private int radiusX;
        private int radiusY;
        private int maxRadiusX;
        private int maxRadiusY;
        private int centerX;
        private int centerY;
        private final int fallSpeed;
        private final boolean orientation;
        private final int[] originalColor = new int[3];
        private final int[] color = new int[originalColor.length];
        private int direction;
        private final boolean haveEight;

        public Star() {
            createRadiuses();
            haveEight = seed.nextBoolean();
            this.centerX = seed.nextInt(w + 1);
            this.centerY = seed.nextInt(h + 1);
            this.fallSpeed = average_fall_speed / 2 + seed.nextInt(average_fall_speed / 2);
            this.orientation = seed.nextBoolean();
            this.direction = -(average_rotation_speed / 2 + seed.nextInt(average_rotation_speed / 2));
            if (seed.nextInt(4) == 0) {
                originalColor[0] = Color.yellow.getRed();
                originalColor[1] = Color.yellow.getGreen();
                originalColor[2] = Color.yellow.getBlue();
            } else {
                originalColor[0] = BasePainter.WATER_LIVE_COLOR.getRed();
                originalColor[1] = BasePainter.WATER_LIVE_COLOR.getGreen();
                originalColor[2] = BasePainter.WATER_LIVE_COLOR.getBlue();
            }
        }

        public void paint(Graphics g, Color forceColor1, Color forceColor2) {
            Color c = g.getColor();
            if (forceColor1 == null || forceColor2 == null) {
                g.setColor(new Color(color[0], color[1], color[2]));
            } else {
                g.setColor(ErrorPainter.interpolateColor(h, centerY, forceColor1, forceColor2));
            }
            Polygon p = createPolygon();
            if (haveEight) {
                int min1 = Math.min(radiusX, radiusY);
                int min2 = min1 / 2;
                g.fillRect(centerX - min2, centerY - min2, min1, min1);
            }
            g.fillPolygon(p);
            g.setColor(c);
        }

        private void animate() {
            centerY += fallSpeed;
            if (orientation) {
                radiusX += direction;
                if (radiusX <= -direction) {
                    direction = -direction;
                    radiusX = direction;
                }
                if (radiusX >= maxRadiusX) {
                    direction = -direction;
                    radiusX = maxRadiusX;
                }
                interpolateColors(radiusX, maxRadiusX);
            } else {
                radiusY += direction;
                if (radiusY <= -direction) {
                    direction = -direction;
                    radiusY = direction;
                }
                if (radiusY >= maxRadiusY) {
                    direction = -direction;
                    radiusY = maxRadiusY;
                }
                interpolateColors(radiusY, maxRadiusY);
            }
            if (centerY > h + radiusX * 2 || centerY > h + radiusY * 2) {
                createRadiuses();
                this.centerX = seed.nextInt(w + 1);
                this.centerY = -radiusY * 2;
            }
        }

        private int createRadius() {
            return average_star_width / 2 + seed.nextInt(average_star_width);
        }

        private Polygon createPolygon() {
            int min = Math.min(radiusX, radiusY) / 3;
            Polygon p = new Polygon();
            p.addPoint(centerX - radiusX, centerY);
            p.addPoint(centerX - min, centerY - min);
            p.addPoint(centerX, centerY - radiusY);
            p.addPoint(centerX + min, centerY - min);
            p.addPoint(centerX + radiusX, centerY);
            p.addPoint(centerX + min, centerY + min);
            p.addPoint(centerX, centerY + radiusY);
            p.addPoint(centerX - min, centerY + min);
            return p;
        }

        private void interpolateColors(int is, int max) {
            for (int i = 0; i < originalColor.length; i++) {
                int fadeMin;
                if (centerY < 0) {
                    fadeMin = 0;
                } else if (centerY > h) {
                    fadeMin = 255;
                } else {
                    fadeMin = (int) ErrorPainter.interpol(h, centerY, 255, 0); //from white  to black
                }
                int fadeMax;
                if (centerY < 0) {
                    fadeMax = 0;
                } else if (centerY > h) {
                    fadeMax = originalColor[i];
                } else {
                    fadeMax = (int) ErrorPainter.interpol(h, centerY, originalColor[i], 0); //from color tho black
                }
                color[i] = (int) ErrorPainter.interpol(max, is, fadeMin, fadeMax);
            }
        }

        private void createRadiuses() {
            this.radiusX = createRadius();
            this.radiusY = radiusX;
            switch (seed.nextInt(3)) {
                case (0):
                    radiusX = radiusX + (2 * radiusX) / 3;
                    break;
                case (1):
                    radiusY = radiusY + (2 * radiusY) / 3;
                    break;
                case (2):
                    //noop
                    break;
            }
            maxRadiusX = radiusX;
            maxRadiusY = radiusY;
        }
    }
    private int w;
    private int h;
    private List<Star> stars = new ArrayList<Star>(50);

    ChristmasExtension(int w, int h) {
        adjustForSize(w, h);
    }

    @Override
    public void paint(Graphics g, BasePainter b) {
        for (ChristmasExtension.Star star : stars) {
            Color forceColor1 = null;
            Color forceColor2 = null;
            if (b instanceof ErrorPainter){
                forceColor1 = b.getBackgroundColor();
                forceColor2 = b.getWaterColor();
            }
            star.paint(g, forceColor1, forceColor2);
        }
    }

    @Override
    public void animate() {
        for (ChristmasExtension.Star star : stars) {
            star.animate();

        }
    }

    @Override
    public final void adjustForSize(int w, int h) {
        this.w = w;
        this.h = h;
        int count = w / (2 * (average_star_width + 1));
        while (stars.size() > count) {
            stars.remove(stars.size() - 1);
        }
        while (stars.size() < count) {
            stars.add(new Star());

        }

    }
}
