import { describe, expect, it } from "vitest";
import { existsSync, readFileSync } from "node:fs";
import { drawTile } from "../src/game/rendering/pixels";
import { TilesetAnimator } from "../src/game/rendering/tileset-animation";
import { CrystalAssets } from "../src/game/rom/assets";
import { OW } from "../src/game/world/constants";
import type { Palette } from "../src/game/world/types";

it("grass priority uses background indices, preserving transparent sprite pixels", () => {
  const palette: Palette = [
    [255, 255, 255],
    [80, 160, 80],
    [32, 64, 32],
    [0, 0, 0],
  ];
  const target = new Uint8ClampedArray(8 * 8 * 4);
  const indices = new Uint8Array(8 * 8);
  const background = new Uint8Array(16);
  background[0] = 0x80; // Colored grass at x=0; color zero elsewhere.
  drawTile(target, 8, 8, background, 0, 0, 0, palette, { indices });
  const sprite = new Uint8Array(16);
  sprite[1] = 0xc0; // Sprite color 2 at x=0 and x=1, transparent at x=2.
  drawTile(target, 8, 8, sprite, 0, 0, 0, palette, {
    indices,
    behind: true,
    transparent: true,
  });
  expect([...target.slice(0, 12)]).toEqual([
    80, 160, 80, 255, 32, 64, 32, 255, 255, 255, 255, 255,
  ]);
  expect([...indices.slice(0, 3)]).toEqual([1, 0, 0]);
  drawTile(target, 8, 8, sprite, 0, 0, 0, palette, {
    indices,
    transparent: true,
  });
  expect([...target.slice(0, 4)]).toEqual([32, 64, 32, 255]);
});

const romPath =
  process.env.CRYSTAL_ROM_PATH ??
  "Pokemon - Crystal Version (UE) (V1.1) [C][!].gbc";
describe.skipIf(!existsSync(romPath))(
  "overworld rendering with the local ROM",
  () => {
    it("runs every tileset animation without changing the cached ROM graphics", () => {
      const assets = new CrystalAssets(new Uint8Array(readFileSync(romPath)));
      const base = assets.map("24:4");
      for (let tileset = 1; tileset <= OW.NUM_TILESETS; tileset++) {
        const map = { ...base, tileset };
        const graphics = assets.tileset(map).graphics;
        const original = graphics.slice();
        const animator = new TilesetAnimator(assets, map, graphics);
        animator.advance(1024, false);
        animator.advance(1024, true);
        expect(graphics, `tileset ${tileset}`).toEqual(original);
        expect(animator.graphics.length).toBe(original.length);
      }
    });

    it("keeps special indoor palettes fixed and uses normal palettes for the Hall of Fame", () => {
      const assets = new CrystalAssets(new Uint8Array(readFileSync(romPath)));
      const base = assets.map("24:6");
      for (const tileset of [
        OW.TILESET_POKECOM_CENTER,
        OW.TILESET_BATTLE_TOWER_INSIDE,
        OW.TILESET_HOUSE,
        OW.TILESET_RADIO_TOWER,
        OW.TILESET_MANSION,
      ]) {
        const map = { ...base, tileset };
        expect(assets.palettes(map, 0)).toEqual(assets.palettes(map, 2));
        expect(assets.palettes(map, 0)).toHaveLength(8);
      }
      const ice = {
        ...base,
        tileset: OW.TILESET_ICE_PATH,
        environment: OW.CAVE,
      };
      expect(assets.palettes(ice, 0)).toEqual(assets.palettes(ice, 2));
      const hall = { ...ice, environment: OW.INDOOR };
      expect(assets.palettes(hall, 1)).not.toEqual(assets.palettes(ice, 1));
      expect(assets.palettes(hall, 1)).toEqual(
        assets.palettes({ ...hall, tileset: OW.TILESET_POKECENTER }, 1),
      );
    });
  },
);