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 { settle } from "./world-driver";

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

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

  const ROUTE_36 = "10:3",
    ROUTE_37 = "10:4",
    ECRUTEAK = "4:9",
    ECRUTEAK_ITEMFINDER_HOUSE = "4:8",
    ECRUTEAK_CENTER = "4:3",
    ECRUTEAK_GYM = "4:7",
    BURNED_TOWER_1F = "3:13",
    BURNED_TOWER_B1F = "3:14";
  const HARD_STONE = 0x7d,
    MAGNET = 0x6c,
    ITEMFINDER = 0x37,
    ETHER = 0x3f,
    ULTRA_BALL = 2,
    HP_UP = 0x1a;
  const EVENT_GOT_HARD_STONE_FROM_ARTHUR = 0x67,
    EVENT_GOT_MAGNET_FROM_SUNNY = 0x69,
    EVENT_GOT_ITEMFINDER = 0x5a;
  // def_scene_scripts numbers each map's own scenes from 0 in file order:
  // EcruteakGymForcedToLeaveScene is 0 (the default), EcruteakGymNoopScene
  // (opened by BurnedTowerB1F's ReleaseTheBeasts) is 1.
  const SCENE_ECRUTEAKGYM_NOOP = 1;
  const EVENT_RELEASED_THE_BEASTS = 0x7b,
    EVENT_BEAT_MORTY = 0x4c0,
    ENGINE_FOGBADGE = 30;

  /** A world on `date`. */
  const world = (date: string) => {
    let seed = 13;
    return new GameWorld(
      new CrystalAssets(bytes),
      () => new Date(date),
      () => {
        seed = (seed * 1103515245 + 12345) >>> 0;
        return (seed >>> 16) & 255;
      },
    );
  };
  /** Stand beside the object at (x, y) on `map` (across a counter if one
   * is in between), face it and press A. The first warpTo runs the map's
   * OBJECTS callback (which the weekday gifts depend on) and settles any
   * entry scene; repositioning after that with restore(), rather than a
   * second settled move, reaches the approach tile in the same tick, so a
   * wandering object (radius > 0) has no window to step away first.
   * restore() also resets object positions to home, since wandering is
   * not saved. */
  const talk = (game: GameWorld, map: string, x: number, y: number) => {
    const target = game.assets.map(map);
    const STEP = {
      up: [0, -1],
      down: [0, 1],
      left: [-1, 0],
      right: [1, 0],
    } as const;
    for (const [face, [dx, dy]] of Object.entries(STEP) as [
      keyof typeof STEP,
      readonly [number, number],
    ][]) {
      const across =
        game.assets.collision(target, x - dx, y - dy) === 0x90 ? 2 : 1;
      const px = x - dx * across,
        py = y - dy * across;
      if (
        px < 0 ||
        py < 0 ||
        px >= target.width ||
        py >= target.height ||
        game.assets.permission(game.assets.collision(target, px, py)) !== 0
      )
        continue;
      try {
        game.warpTo(map, px, py);
      } catch {
        continue;
      }
      settle(game);
      game.restore({ ...game.save(), x: px, y: py, direction: face });
      game.interact();
      return;
    }
    throw new Error(`No place to talk to ${x},${y} on ${map}`);
  };
  /** Advance to the next choice, keeping the pages shown. */
  const next = (game: GameWorld, pages: string[] = []) => {
    for (let tick = 0; tick < 4000; tick++) {
      const dialogue = game.dialogue;
      if (dialogue) {
        const page = dialogue.pages[dialogue.index].replace(/\n/g, " ");
        if (page && pages.at(-1) !== page) pages.push(page);
        if (dialogue.index === dialogue.pages.length - 1 && dialogue.choice)
          return dialogue.choice;
        if (dialogue.index === dialogue.pages.length - 1 && dialogue.holdTicks !== undefined)
          game.tick();
        else game.advanceDialogue();
      } else if (game.busy) game.tick();
      else return undefined;
    }
    throw new Error(`No choice: ${game.diagnostic}`);
  };
  /** Accept yes/no prompts and advance text until the interaction ends. */
  const finish = (game: GameWorld, pages: string[] = []) => {
    for (let step = 0; step < 200; step++) {
      const choice = next(game, pages);
      if (!choice) {
        expect(game.notice, game.diagnostic).toBe("");
        return pages.join(" ");
      }
      if (choice.kind === "name") game.choose("");
      else game.choose(choice.kind === "yesno" ? 1 : 0);
    }
    throw new Error("Interaction did not finish.");
  };

  it("gives Arthur's Hard Stone only on Thursday, once met", () => {
    const notThursday = world("2026-09-22T12:00:00"); // Tuesday
    talk(notThursday, ROUTE_36, 46, 6); // Arthur is hidden on a non-Thursday.
    expect(notThursday.notice).toBe("Nothing to interact with here.");

    const game = world("2026-09-24T12:00:00"); // Thursday
    talk(game, ROUTE_36, 46, 6);
    let pages: string[] = [];
    let text = finish(game, pages);
    expect(text).toMatch(/Who are\s+you/);
    expect(game.state.events.has(EVENT_GOT_HARD_STONE_FROM_ARTHUR)).toBe(true);
    expect(game.state.bag.items).toContainEqual({ item: HARD_STONE, quantity: 1 });

    // Talking again on the same day shows the "already have it" text.
    talk(game, ROUTE_36, 46, 6);
    pages = [];
    text = finish(game, pages);
    expect(text).toMatch(/second son/i);
  });

  it("gives Sunny's Magnet only on Sunday, once met", () => {
    const game = world("2026-09-20T12:00:00"); // Sunday
    talk(game, ROUTE_37, 16, 8);
    const pages: string[] = [];
    const text = finish(game, pages);
    expect(text).toMatch(/SUNNY: Hi!/);
    expect(game.state.events.has(EVENT_GOT_MAGNET_FROM_SUNNY)).toBe(true);
    expect(game.state.bag.items).toContainEqual({ item: MAGNET, quantity: 1 });
  });

  it("gives the Itemfinder from the house south of Tin Tower", () => {
    const game = world("2026-09-22T12:00:00");
    talk(game, ECRUTEAK_ITEMFINDER_HOUSE, 2, 3);
    const pages: string[] = [];
    const text = finish(game, pages);
    expect(text).toMatch(/true spirit/i);
    expect(game.state.events.has(EVENT_GOT_ITEMFINDER)).toBe(true);
    // ITEMFINDER is a key item (ItemAttributes' pocket byte).
    expect(game.state.bag.keyItems).toContain(ITEMFINDER);
  });

  it("answers CheckMobileAdapterStatusSpecial's non-mobile branch at the Pokémon Center", () => {
    const game = world("2026-09-22T12:00:00");
    // The default scene (EcruteakPokecenter1FMeetBillScene) plays out and
    // moves the player on the first visit; let it finish before walking
    // over to the PokéFan.
    game.warpTo(ECRUTEAK_CENTER, 3, 7);
    finish(game);
    talk(game, ECRUTEAK_CENTER, 7, 6);
    const text = finish(game);
    // CheckMobileAdapterStatusSpecial always clears wScriptVar in this
    // revision (CheckMobileAdapterStatus is the Japanese version's
    // routine), so the non-mobile KIMONO GIRLS text always shows.
    expect(text).toMatch(/KIMONO GIRLS/);
    expect(text).not.toMatch(/OLIVINE CITY/);
  });

  it("keeps Morty's gym closed until the Burned Tower beasts are released", () => {
    // EcruteakGymForcedToLeaveScene is the default scene (0); only
    // BurnedTowerB1F's ReleaseTheBeasts (board #32's roaming increment,
    // out of scope here) sets SCENE_ECRUTEAKGYM_NOOP to open it. Morty's
    // own dialogue in Burned Tower 1F explains why: he is investigating
    // the tower with Eusine instead of running the gym.
    const game = world("2026-09-22T12:00:00");
    game.warpTo(ECRUTEAK_GYM, 5, 17);
    const pages = settle(game);
    expect(game.notice, game.diagnostic).toBe("");
    expect(pages.join(" ")).toMatch(/is absent/i);
    expect(game.mapId).toBe(ECRUTEAK);
    expect(game.battle).toBeUndefined();
  });

  it("finds Burned Tower 1F's hidden items and HP Up, and cannot smash its rock yet", () => {
    const game = world("2026-09-22T12:00:00");
    game.warpTo(BURNED_TOWER_1F, 9, 15);
    settle(game); // the Eusine scene (sdefer) runs on the first idle tick
    expect(game.notice, game.diagnostic).toBe("");

    game.restore({ ...game.save(), x: 7, y: 7, direction: "right" });
    game.interact();
    finish(game);
    expect(game.state.bag.items).toContainEqual({ item: ETHER, quantity: 1 });

    game.restore({ ...game.save(), x: 13, y: 12, direction: "up" });
    game.interact();
    finish(game);
    expect(game.state.bag.balls).toContainEqual({ item: ULTRA_BALL, quantity: 1 });

    game.restore({ ...game.save(), x: 14, y: 3, direction: "up" });
    game.interact();
    finish(game);
    expect(game.state.bag.items).toContainEqual({ item: HP_UP, quantity: 1 });

    game.restore({ ...game.save(), x: 15, y: 5, direction: "up" });
    game.interact();
    expect(finish(game)).toMatch(/Maybe a.*POKéMON.*break/i);
  });

  it("asks for Strength at Burned Tower B1F's boulder, which is not obtainable yet", () => {
    // The TM Endure behind it stays unreachable until a much later card
    // gives Strength; AskStrengthScript (jumpstd StrengthBoulderScript)
    // should still answer sensibly rather than refusing outright.
    const game = world("2026-09-22T12:00:00");
    game.warpTo(BURNED_TOWER_B1F, 17, 9);
    settle(game);
    game.restore({ ...game.save(), x: 17, y: 9, direction: "up" });
    game.interact();
    expect(finish(game)).toMatch(/may be able to move this/i);
  });

  it("opens Ecruteak Gym's guide and statue text once Morty is reachable, then again once he is beaten", () => {
    // BurnedTowerB1F's ReleaseTheBeasts sets SCENE_ECRUTEAKGYM_NOOP; drive
    // that directly, as the playthrough's own roaming-beast stage (out of
    // scope for this focused file) otherwise would.
    const game = world("2026-09-22T12:00:00");
    game.warpTo(ECRUTEAK_GYM, 5, 17);
    game.state.scenes[ECRUTEAK_GYM] = SCENE_ECRUTEAKGYM_NOOP;
    settle(game);
    expect(game.mapId).toBe(ECRUTEAK_GYM);

    game.restore({ ...game.save(), x: 7, y: 16, direction: "up" }); // the Gym Guide
    game.interact();
    let text = finish(game);
    expect(text).toMatch(/secret mo-?\s*tives/i);

    game.restore({ ...game.save(), x: 3, y: 16, direction: "up" }); // the left statue
    game.interact();
    text = finish(game);
    expect(text).toMatch(/#MON GYM|POKéMON GYM/);
    expect(text).not.toMatch(/WINNING TRAINERS/);

    // EcruteakGymGuideScript checks EVENT_BEAT_MORTY; EcruteakGymStatue
    // checks ENGINE_FOGBADGE instead. Beating Morty sets both together,
    // but this isolated test drives each script without a real battle.
    game.state.events.add(EVENT_BEAT_MORTY);
    game.state.flags.add(ENGINE_FOGBADGE);

    game.restore({ ...game.save(), x: 7, y: 16, direction: "up" });
    game.interact();
    text = finish(game);
    expect(text).toMatch(/cowering in/i);

    game.restore({ ...game.save(), x: 6, y: 16, direction: "up" }); // the right statue
    game.interact();
    text = finish(game);
    expect(text).toMatch(/LEADER:\s*MORTY/i);
    expect(text).toMatch(/WINNING TRAINERS/);
  });

  it("shows Ecruteak City's beasts-released text once they are released", () => {
    const before = world("2026-09-22T12:00:00");
    talk(before, ECRUTEAK, 3, 9); // EcruteakCityLass2 (the old tower)
    expect(finish(before)).toMatch(/tower that.*used to be here/i);

    const after = world("2026-09-22T12:00:00");
    after.state.events.add(EVENT_RELEASED_THE_BEASTS);
    talk(after, ECRUTEAK, 3, 9);
    expect(finish(after)).toMatch(/ran off in differ-?\s*ent directions/i);
  });
});