import { describe, expect, it } from "vitest";
import { existsSync, readFileSync } from "node:fs";
import { CrystalAssets } from "../src/game/rom/assets";
import { GameWorld } from "../src/game/world/world";
import { generatePartyMon } from "../src/game/party/pokemon";
import { settle } from "./world-driver";

const romPath =
  process.env.CRYSTAL_ROM_PATH ?? "Pokemon - Crystal Version (UE) (V1.1) [C][!].gbc";

describe.skipIf(!existsSync(romPath))("Blackthorn City with the local ROM", () => {
  const bytes = existsSync(romPath) ? new Uint8Array(readFileSync(romPath)) : new Uint8Array();

  const MOVE_DELETERS_HOUSE = "5:7",
    DRAGON_SHRINE = "3:82";
  const TYPHLOSION = 157,
    DRATINI = 147,
    SCENE_DRAGONSHRINE_NOOP = 1;
  const WRAP = 35,
    LEER = 43,
    THUNDER_WAVE = 86,
    TWISTER = 239,
    EXTREMESPEED = 245;
  const EVENT_GOT_DRATINI = 0xbd,
    EVENT_ANSWERED_DRAGON_MASTER_QUIZ_WRONG = 0xc1;

  const world = () => {
    let seed = 13;
    return new GameWorld(
      new CrystalAssets(bytes),
      () => new Date("2026-09-22T12:00:00"),
      () => {
        seed = (seed * 1103515245 + 12345) >>> 0;
        return (seed >>> 16) & 255;
      },
    );
  };
  const mon = (game: GameWorld, species: number, level = 30) =>
    generatePartyMon(game.assets.pokemon, {
      species,
      level,
      item: 0,
      otId: game.playerId,
      ot: "KAWA",
      dvs: 0x8888,
      caughtData: 0,
    });
  /** Enter `map`, stand at (x, y) facing `face`, press A and answer. */
  const talk = (
    game: GameWorld,
    map: string,
    x: number,
    y: number,
    face: "up" | "down" | "left" | "right",
    answers: (number | string)[] = [],
  ) => {
    game.warpTo(map, x, y);
    settle(game);
    game.restore({ ...game.save(), x, y, direction: face });
    game.interact();
    const shown = settle(game, answers).join(" ");
    expect(game.notice, game.diagnostic).toBe("");
    return shown;
  };
  /** The Move Deleter stands at (2, 3). */
  const deleter = (game: GameWorld, answers: number[]) =>
    talk(game, MOVE_DELETERS_HOUSE, 2, 4, "up", answers);

  describe("the Move Deleter (MoveDeletion)", () => {
    it("deletes the chosen move and moves the later moves and PP up", () => {
      const game = world();
      const typhlosion = mon(game, TYPHLOSION);
      typhlosion.moves = [33, 43, 108, 52];
      typhlosion.pp = [35, 30 | 0xc0, 20, 25 | 0x40];
      game.state.party = [typhlosion];
      // YES, the first Pokémon, its second move (LEER), YES.
      const shown = deleter(game, [1, 0, 1, 1]);
      expect(shown).toContain("the MOVE DELETER.");
      expect(shown).toContain("Oh, make it forget\nLEER?");
      expect(shown).toContain("forgot the move.");
      // The PP Up bits move with each move's PP.
      expect(game.state.party[0].moves).toEqual([33, 108, 52, 0]);
      expect(game.state.party[0].pp).toEqual([35, 20, 25 | 0x40, 0]);
    });

    it("refuses a Pokémon with one move and an Egg, and says goodbye to every no", () => {
      const game = world();
      const one = mon(game, TYPHLOSION);
      one.moves = [33, 0, 0, 0];
      one.pp = [35, 0, 0, 0];
      const egg = { ...mon(game, TYPHLOSION, 5), egg: true };
      game.state.party = [one, egg, mon(game, TYPHLOSION)];
      expect(deleter(game, [1, 0])).toContain("knows\nonly one move.");
      expect(deleter(game, [1, 1])).toContain("An EGG doesn't");
      const before = structuredClone(game.state.party[2]);
      expect(deleter(game, [0])).toContain("Come visit me");
      expect(deleter(game, [1, -1])).toContain("Come visit me");
      expect(deleter(game, [1, 2, -1])).toContain("Come visit me");
      expect(deleter(game, [1, 2, 0, 0])).toContain("Come visit me");
      expect(game.state.party[2]).toEqual(before);
    });
  });

  describe("the Dragon Shrine elder's Dratini (GiveDratini)", () => {
    /** After the test (the shrine's scene done), talk to the elder. */
    const elder = (game: GameWorld) => {
      game.state.scenes[DRAGON_SHRINE] = SCENE_DRAGONSHRINE_NOOP;
      return talk(game, DRAGON_SHRINE, 5, 2, "up", [0]);
    };

    it("gives a Dratini with Extremespeed after a test without mistakes", () => {
      const game = world();
      game.state.party = [mon(game, TYPHLOSION)];
      const shown = elder(game);
      expect(shown).toContain("Take this DRATINI");
      expect(game.state.events.has(EVENT_GOT_DRATINI)).toBe(true);
      const dratini = game.state.party[1];
      expect(dratini).toMatchObject({ species: DRATINI, level: 15 });
      expect(dratini.moves).toEqual([WRAP, THUNDER_WAVE, TWISTER, EXTREMESPEED]);
      // Each move's base PP, as .GiveMoves reads it from Moves.
      expect(dratini.pp).toEqual([20, 20, 20, 5]);
      // Re-entering clears EVENT_TEMPORARY_UNTIL_MAP_RELOAD_7.
      expect(elder(game)).toContain("CLAIR appears to");
    });

    it("gives the normal moves after a mistake, to the last Dratini only", () => {
      const game = world();
      game.state.events.add(EVENT_ANSWERED_DRAGON_MASTER_QUIZ_WRONG);
      const earlier = mon(game, DRATINI, 20);
      game.state.party = [earlier, mon(game, TYPHLOSION)];
      const before = structuredClone(earlier);
      elder(game);
      expect(game.state.party[2].moves).toEqual([WRAP, LEER, THUNDER_WAVE, TWISTER]);
      expect(game.state.party[2].pp).toEqual([20, 30, 20, 20]);
      expect(game.state.party[0]).toEqual(before);
    });

    it("keeps the Dratini for later when the party is full", () => {
      const game = world();
      game.state.party = Array.from({ length: 6 }, () => mon(game, TYPHLOSION));
      expect(elder(game)).toContain("party is full.");
      expect(game.state.events.has(EVENT_GOT_DRATINI)).toBe(false);
      game.state.party.pop();
      elder(game);
      expect(game.state.party[5].species).toBe(DRATINI);
    });
  });
});