#!/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
import functools


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)
    @property
    def len(self):
        return math.sqrt(self.x**2 + self.y**2)


class PointLenOrder:
    def __init__(self, value):
        self.value = value
    def __eq__(self, other):
        return other.value.len == self.value.len
    def __lt__(self, other):
        return other.value.len < self.value.len


DIRECTIONS = [ Point(x, y) for x in [-1, 1] for y in [-1, 1] ]


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 Line:
    def __init__(self, worldsize):
        self.worldsize = worldsize
        self.line = [Point(random.randint(0, worldsize.x),
                           random.randint(0, worldsize.y))]
        self.slen = 1
        self.dir = random.choice(DIRECTIONS)
        self.color = get_random_color()
        diaglen = int(math.sqrt(worldsize.x**2 + worldsize.y**2))
        self.maxlen = random.randint(diaglen, diaglen * 3)
        self.fadeout_time = 2 + random.random() * 2
        self.fadeout_remaining = None
        self.finished = False

    def check_bounds(self, p):
        return p.x < self.worldsize.x and p.x >= 0 \
               and p.y < self.worldsize.y and p.y >= 0

    def update(self, t, dt):
        if len(self.line) < self.maxlen:
            if self.slen >= 3 and random.random() < 0.4:
                dirs = list(DIRECTIONS)
                dirs.remove(self.line[-1] - self.line[-2])
                if self.check_bounds(self.line[-1]):
                    newp = None
                    while newp is None or newp == self.line[-2]:
                        self.dir = random.choice(dirs)
                        newp = self.line[-1] + self.dir
                else:
                    dirs.sort(key=lambda d: ((self.line[-1]+d) - Point(0, 0)).len)
                    self.dir = dirs[0]
                self.slen = 1
            else:
                self.slen += 1
            self.line.append(self.line[-1] + self.dir)
        else:
            if self.fadeout_remaining is None:
                self.fadeout_remaining = self.fadeout_time
            elif self.fadeout_remaining <= 0:
                self.finished = True
            else:
                self.fadeout_remaining -= dt

    def draw(self, frame):
        if self.fadeout_remaining is not None:
            if self.fadeout_remaining > 0:
                h, s, v = colorsys.rgb_to_hsv(*self.color)
                v = v * (self.fadeout_remaining / self.fadeout_time)
                color = colorsys.hsv_to_rgb(h, s, v)
            else:
                color = (0, 0, 0)
        else:
            color = self.color
        for p in self.line:
            if self.check_bounds(p):
                frame.setPixel(p.x, p.y, convert_color(color))


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)


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

        for l in lines:
            l.update(t, dt)
            l.draw(frame)

        if lines[-1].fadeout_remaining is not None:
            lines.append(Line(Point(WIDTH, HEIGHT)))

        for l in lines:
            if l.finished:
                lines.remove(l)

        anim.addFrame(frame)

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