from typing import Any
import pygame as pg

from .settings import *


class App:
    def __init__(self) -> None:
        from .tetris import Tetris

        # TODO: dynamic timeout
        self.fall_timeout: Generator[int, Any, Any] = FALL_TIMEOUT_GENERATOR
        self.paused = False

        pg.init()
        pg.display.set_caption(CAPTION)
        self.init_event_timer()
        self.screen = pg.display.set_mode(FIELD_RES)
        self.clock = pg.time.Clock()
        self.tetris = Tetris(self)

    def init_event_timer(self):
        # when timeout, set trigger to true to make tetromino fall
        self.fall_trigger = False
        self.fall_event = pg.USEREVENT
        pg.time.set_timer(self.fall_event, next(self.fall_timeout))

    def update(self):
        self.tetris.update()
        self.clock.tick(FPS)

    def draw(self):
        '''
        main app frame drawer. This method only run once.
        draw app background color
        draw tetris grids
        '''
        self.screen.fill(color=FIELD_COLOR, rect=(0, 0, *FIELD_RES))
        self.tetris.draw()  # draw grid
        pg.display.flip()

    def check_events(self):
        '''
        Main event loop.
        '''
        self.fall_trigger = False  # fall_event set in set_event_timer
        for event in pg.event.get():
            if event.type == pg.QUIT or (
                    event.type == pg.KEYDOWN and event.key == pg.K_ESCAPE
                    or event.type == pg.KEYDOWN and event.key == pg.K_c
                    and pg.key.get_mods() & pg.KMOD_CTRL
            ):  # handle ctrl+c, https://stackoverflow.com/a/46506753/20419707
                pg.quit()
                exit()
            elif event.type == pg.KEYDOWN:
                if event.key == pg.K_p:
                    self.paused = not self.paused
                elif not self.paused:
                    self.tetris.control(event.key)
            elif event.type == self.fall_event and not self.paused:
                self.fall_trigger = True
                pg.time.set_timer(self.fall_event, next(self.fall_timeout))

    def run(self):
        '''
        Main loop.
        '''
        while True:
            self.check_events()
            self.update()
            self.draw()