import os
import datetime

from time import sleep # debug

class Color:
    cache_closest_printable_color = 0

    def __init__(self, r: float = 0.0, g: float = 0.0, b: float = 0.0):
        self.set(r, g, b)
        self.update()
    
    def set(self, r, g, b):
        self.r, self.g, self.b = r, g, b
    
    def update(self):
        self._r, self._g, self._b = self.r, self.g, self.b
    
    def hasChange(self) -> bool:
        return any(x != y for x, y in {self._r: self.r, self._g: self.g, self._b: self.b}.items())

    def distance(self, to) -> float:
        dr = self.r - to.r
        dg = self.g - to.g
        db = self.b - to.b
        return (dr * dr + dg * dg + db * db) ** .5

    def getClosestPrintableColor(self) -> int:
        if not self.hasChange():
            return self.cache_closest_printable_color

        closest_distance = float("inf")
        closest_value = 0
        for k, v in COLORS.items():
            distance = self.distance(k)
            if closest_distance > distance:
                closest_distance = distance
                closest_value = v

        self.cache_closest_printable_color = closest_value
        self.update()

        return closest_value

class Pixel:
    char = " "
    text_color = Color()
    background_color = Color()

    cached_text_color_value = -1
    cached_background_color_value = -1

    def __str__(self) -> str:
        color = ""

        text_color = self.text_color.getClosestPrintableColor()
        if text_color != self.cached_text_color_value:
            color += COLOR_FORMAT % (text_color + COLOR_TEXT)
            self.cached_text_color_value = text_color

        background_color = self.background_color.getClosestPrintableColor()
        if background_color != self.cached_background_color_value:
            color += COLOR_FORMAT % (background_color + COLOR_BACKGROUND)
            self.cached_background_color_value = background_color

        
        return color + self.char
    
    def reset(self):
        self.cached_text_color_value = -1
        self.cached_background_color_value = -1

class Screen:
    def __init__(self, width: int, height: int, std_handle: int = 0, render_funcs = []):
        self.width = width
        self.height = height
        self.std_handle = std_handle
        self.render_funcs = render_funcs

        self.time_start = datetime.datetime.now()
        self.buffer = ""

        self.dynamic = self.height < 0 and self.width < 0
    
    def get_time(self):
        return (datetime.datetime.now() - self.time_start).total_seconds()
    
    def write(self, string):
        self.buffer += string
    
    def flush(self):
        print(self.buffer, end="", flush=True)
        self.buffer = ""

    def mainloop(self):
        pixel = Pixel()

        while True:
            width, height = os.get_terminal_size(self.std_handle)

            if self.dynamic:
                self.width, self.height = width, height

            if width < self.width or height < self.height:
                Screen.clear()
                print("Unable to print the screen, a terminal with %dx%d (and above) chars are required to continue" % (self.width, self.height))
                while width < self.width or height < self.height:
                    width, height = os.get_terminal_size(self.std_handle)

            time = self.get_time()

            resolution = (self.width, self.height)
            for y in range(self.height):
                for x in range(self.width):
                    for render_func in self.render_funcs:
                        render_func(pixel, resolution, (x, y), time)
                    self.write(str(pixel))
                pixel.reset()
                self.write("\x1b[0m\n") # newline

            #Screen.clear()
            #self.flush()
            self.new_flush()
            #sleep(.01)

    def new_flush(self):
        self.buffer = "\x1b[0;0H" + self.buffer
        self.flush()

    @staticmethod
    def clear():
        print("\x1b[2J", end="", flush=True)

COLOR_RESET = 0
COLOR_TEXT = 30
COLOR_BACKGROUND = 40
COLOR_FORMAT = "\x1b[%dm"
COLORS = {
    Color(0.0, 0.0, 0.0): 0,
    Color(1.0, 0.0, 0.0): 1,
    Color(0.0, 1.0, 0.0): 2,
    Color(1.0, 1.0, 0.0): 3,
    Color(0.0, 0.0, 1.0): 4,
    Color(1.0, 0.0, 1.0): 5,
    Color(0.0, 1.0, 1.0): 6,
    Color(1.0, 1.0, 1.0): 7
}