#!/usr/bin/env python3

import sys
import random
import math
import argparse
import collections
import blup.frame
import blup.output
import blup.animation
import blup.writebml
import colorsys


WIDTH = 22
HEIGHT = 16
DEPTH = 256


class Point(collections.namedtuple('Point', ['x', 'y'])):
    def __add__(self, other):
        return Point(self.x + other.x, self.y + other.y)
    def __sub__(self, other):
        return Point(self.x - other.x, self.y - other.y)
    def __mul__(self, other):
        if isinstance(other, Point):
            raise Exception('not implemented')
        else:
            return Point(self.x * other, self.y * other)
    def __truediv__(self, other):
        if isinstance(other, Point):
            raise ValueError()
        else:
            return self * (1/other)
    @property
    def len(self):
        return math.sqrt(self.x**2 + self.y**2)
    @property
    def n(self):
        n = Point(self.y, -self.x)
        return n / n.len
    @property
    def intp(self):
        return Point(int(round(self.x)), int(round(self.y)))


def convert_color(c):
    return list(map(lambda x: int(round(x*(DEPTH-1))), c))


def get_random_color():
    return colorsys.hsv_to_rgb(random.random(), 0.5 + random.random() / 2, 1)


class Twister:
    def __init__(self, worldsize):
        self.worldsize = worldsize
        self.cycletime = 1.3
        self.sat = 0.5 + random.random() / 2
        self.hues = [random.random()]
        self.hues += [ self.hues[0] + (i+1) * 0.25 for i in range(3) ]
        random.shuffle(self.hues)
        self.width = worldsize.x // 2.9

    def update(self, t, dt):
        # inspired by https://www.lexaloffle.com/bbs/?tid=3050

        self.rows = []
        a0 = t * math.pi / self.cycletime
        while len(self.rows) < self.worldsize.y:
            y = len(self.rows)
            a = a0 - y * math.pi / self.worldsize.y \
                * (math.sin(t * math.pi / 10) * 0.7)
            ot1 = t * math.pi / 5
            ot2 = y * math.pi / (self.worldsize.y * 2)
            offs = self.worldsize.x / 2 + math.sin(ot1 + ot2) * self.width / 2
            x1 = int(round(offs + self.width * math.sin(a)))
            x2 = int(round(offs + self.width * math.sin(a+0.5*math.pi)))
            x3 = int(round(offs + self.width * math.sin(a+math.pi)))
            x4 = int(round(offs + self.width * math.sin(a+1.5*math.pi)))
            row = []
            for i, (start, end) in enumerate([(x1, x2), (x2, x3),
                                              (x3, x4), (x4, x1)]):
                if start < end:
                    row += [(x, i, (x - start) / (end - start - 1)) 
                            for x in range(start, end - 1)]
            self.rows.append(row)

    def draw(self, frame):
        for y, line in enumerate(self.rows):
            for point in line:
                x, i, j = point
                val = 1 - math.sin(j * math.pi) / 2.3
                color = colorsys.hsv_to_rgb(self.hues[i], self.sat, val)
                try:
                    frame.setPixel(x, y, convert_color(color))
                except ValueError:
                    pass


if __name__ == '__main__':
    parser = argparse.ArgumentParser(description='Generate animations')
    parser.add_argument('-d', '--delay', type=int, default=50)
    parser.add_argument('-t', '--time', type=int, default=15)
    parser.add_argument('output_file')
    args = parser.parse_args()

    dim = blup.frame.FrameDimension(WIDTH, HEIGHT, DEPTH, 3)
    anim = blup.animation.Animation(dim)
    anim.tags['description'] = ' '.join(sys.argv)

    twister = Twister(Point(WIDTH, HEIGHT))
    t = 0
    dt = args.delay / 1000
    while t < args.time:
        t += dt
        frame = blup.animation.AnimationFrame(dim, args.delay)

        twister.update(t, dt)
        twister.draw(frame)

        anim.addFrame(frame)

    blup.writebml.writeBml(anim, args.output_file)