from math import floor
import os
from typing import Optional

import pygame


class Editor:
    WIDTH = 800
    HEIGHT = 600
    MAP_SIZE = 1024
    MAPS_DIR = "/tmp/lycacraft_maps"
    MIN_ZOOM = 0.25
    MAX_ZOOM = 4

    def __init__(self):
        self.width: int = self.WIDTH
        self.height: int = self.HEIGHT
        self.win: pygame.Surface = pygame.display.set_mode([self.width, self.height], pygame.RESIZABLE)
        self.center: list[int] = [0, 0]
        self.zoom: float = 1
        self.map_size: int = self.MAP_SIZE
        self.running: bool = False
        self.cache: dict[float, dict[tuple[int, int], pygame.Surface]] = {}
        self.load_maps()
        self.clock: pygame.time.Clock = pygame.time.Clock()
        self.visible_maps_count: int = 0
        self.drag_pos: Optional[tuple[int, int]] = None

    def load_maps(self) -> None:
        cache = {}
        for path in os.listdir(self.MAPS_DIR):
            fullpath = os.path.join(self.MAPS_DIR, path)
            name, x, y = path.split(".")[0].split("_")
            cache[(int(x), int(y))] = pygame.image.load(fullpath)
        self.cache = {
            self.zoom: cache
        }

    def resize_maps(self) -> None:
        if self.zoom in self.cache:
            return

        cache = {}
        for pos, img in self.cache[1].items():
            cache[pos] = pygame.transform.scale_by(img, self.zoom)

        self.cache[self.zoom] = cache

    def get_map(self, x: int, y: int) -> Optional[pygame.Surface]:
        cache = self.cache.get(self.zoom, {})
        pos = (x, y)
        if pos not in cache:
            if pos not in self.cache[1]:
                return None

            img = self.cache[1][pos]
            cache[pos] = pygame.transform.scale_by(img, self.zoom)

        return cache[pos]

    def mainloop(self) -> None:
        self.running = True
        while self.running:
            pygame.display.set_caption(f"Lycacraft Map Editor - {self.clock.get_fps():.2f}fps - {self.visible_maps_count} maps rendered")
            self.process_events()
            self.render()
            self.clock.tick(30)

    def process_events(self) -> None:
        events = pygame.event.get()

        for event in events:
            if event.type == pygame.QUIT:
                self.running = False
            elif event.type == pygame.WINDOWRESIZED:
                self.width = event.x
                self.height = event.y
            elif event.type == pygame.KEYDOWN:
                if event.key == pygame.K_ESCAPE:
                    self.running = False
                elif event.key == pygame.K_PAGEUP:
                    self.zoom_in()
                elif event.key == pygame.K_PAGEDOWN:
                    self.zoom_out()
            elif event.type == pygame.MOUSEBUTTONDOWN:
                if event.button == 2:
                    self.drag_pos = event.pos
            elif event.type == pygame.MOUSEBUTTONUP:
                if event.button == 2:
                    self.drag_pos = None

        keys = pygame.key.get_pressed()
        if keys[pygame.K_LEFT]:
            self.center[0] -= 4 / self.zoom
        if keys[pygame.K_RIGHT]:
            self.center[0] += 4 / self.zoom
        if keys[pygame.K_UP]:
            self.center[1] -= 4 / self.zoom
        if keys[pygame.K_DOWN]:
            self.center[1] += 4 / self.zoom

        mbtns = pygame.mouse.get_pressed()
        mpos = pygame.mouse.get_pos()
        if mbtns[1]:
            dx = mpos[0] - self.drag_pos[0]
            dy = mpos[1] - self.drag_pos[1]
            self.center[0] -= dx / self.zoom
            self.center[1] -= dy / self.zoom
            self.drag_pos = mpos

    def render(self) -> None:
        self.win.fill((0, 0, 0))
        off_x = self.center[0] % self.MAP_SIZE
        off_y = self.center[1] % self.MAP_SIZE

        w2 = self.width / 2
        h2 = self.height / 2

        x0 = floor(self.center[0] - w2 / self.zoom)
        y0 = floor(self.center[1] - h2 / self.zoom)
        x1 = floor(self.center[0] + w2 / self.zoom)
        y1 = floor(self.center[1] + h2 / self.zoom)

        mx0 = floor(x0 / self.MAP_SIZE)
        my0 = floor(y0 / self.MAP_SIZE)
        mx1 = floor(x1 / self.MAP_SIZE)
        my1 = floor(y1 / self.MAP_SIZE)

        h_maps = mx1 - mx0 + 1
        v_maps = my1 - my0 + 1
        cx = floor(self.center[0] / self.MAP_SIZE)
        cy = floor(self.center[1] / self.MAP_SIZE)
        self.visible_maps_count = h_maps * v_maps
        ox = w2 + (mx0 - cx) * self.map_size - off_x * self.zoom
        oy = h2 + (my0 - cy) * self.map_size - off_y * self.zoom
        # cache = self.cache[self.zoom]

        for y in range(v_maps):
            for x in range(h_maps):
                # map_pos = (mx0 + x, my0 + y)
                map_image = self.get_map(mx0 + x, my0 + y)
                # if map_pos not in cache:
                if map_image is None:
                    continue

                # map_image = cache[map_pos]

                sx = ox + x * self.map_size
                sy = oy + y * self.map_size
                ex = sx + self.map_size
                ey = sy + self.map_size
                sx2, ex2 = min(self.width, max(0, sx)), min(self.width, max(0, ex))
                sy2, ey2 = min(self.height, max(0, sy)), min(self.height, max(0, ey))
                """self.win.blit(map_image, [
                    ox + x * self.map_size,
                    oy + y * self.map_size,
                ])"""
                self.win.blit(map_image, [sx2, sy2], [sx2 - sx, sy2 - sy, ex2 - sx2, ey2 - sy2])

        for y in range(v_maps):
            for x in range(h_maps):
                pygame.draw.rect(self.win, (255, 0, 0), [ox + x * self.map_size, oy + y * self.map_size, self.map_size, self.map_size], 1)

        pygame.display.flip()

    def set_zoom(self, zoom: float) -> None:
        self.zoom = max(self.MIN_ZOOM, min(self.MAX_ZOOM, zoom))
        self.map_size = self.MAP_SIZE * self.zoom
        # self.resize_maps()

    def zoom_in(self) -> None:
        self.set_zoom(self.zoom * 2)

    def zoom_out(self) -> None:
        self.set_zoom(self.zoom / 2)