import { beforeAll, 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, walkTo } from "./world-driver";
import { questFixtureWorld, questLabFixtureWorld, questRivalFixtureWorld } from "./quest-fixture";

const romPath = process.env.CRYSTAL_ROM_PATH ?? "Pokemon - Crystal Version (UE) (V1.1) [C][!].gbc";
const HOUSE = "26:10", EGG = 0x45;

describe.skipIf(!existsSync(romPath))("Mr. Pokémon's house with the local ROM", () => {
  function fixture(species = 155, refuseHealing = false) {
    const bytes = new Uint8Array(readFileSync(romPath));
    // FadeInFromBlackSpecial's table entry: refuse the routine after rewards
    // and healing to check the complete interaction's rollback boundary.
    if (refuseHealing) bytes.set([0, 0, 0x40], 0xc0bf);
    const assets = new CrystalAssets(bytes);
    const world = new GameWorld(assets, () => new Date("2026-09-24T12:00:00"));
    const mon = generatePartyMon(assets.pokemon, {
      species, level: 5, item: 0, otId: world.playerId,
      ot: "CHRIS", dvs: 0xffff, caughtData: 0,
    });
    mon.hp = 1;
    mon.status = 8;
    mon.pp[0] = 0;
    world.state.party = [mon];
    world.state.events.add(species === 155 ? 27 : species === 158 ? 28 : 29);
    world.state.events.add(1794);
    world.state.events.add(1939);
    world.restore({ ...world.save(), map: "26:1", x: 17, y: 6, direction: "up" });
    expect(world.move("up")).toBe(true);
    expect(world.mapId).toBe(HOUSE);
    return world;
  }

  it.each([[155, 1601], [158, 1602], [152, 1600]])("gives the Egg and Pokédex, heals starter %i, and sets the return quest", (species, stolenBall) => {
    const world = fixture(species);
    const pages = settle(world).join("\n");
    expect(world.notice, world.diagnostic).toBe("");
    expect(pages).toContain("MYSTERY EGG");
    expect(pages).toContain("DEX");
    expect(world.state.bag.keyItems).toEqual([EGG]);
    expect(world.state.flags.has(11)).toBe(true);
    for (const event of [30, 1737, 1725, 1938, stolenBall])
      expect(world.state.events.has(event), String(event)).toBe(true);
    for (const event of [1794, 1939]) expect(world.state.events.has(event)).toBe(false);
    expect(world.state.lastSpawnMap).toBe("26:3");
    expect(world.state.scenes).toMatchObject({ [HOUSE]: 1, "26:3": 1, "24:5": 3 });
    expect(world.state.specialPhoneCall).toBe(2);
    expect(world.objects().some((object) => object.id === 3)).toBe(false);
    const mon = world.state.party[0];
    expect(mon.hp).toBe(mon.stats[0]);
    expect(mon.status).toBe(0);
    expect(mon.pp[0]).toBe(world.assets.pokemon.move(mon.moves[0]).pp);
    // The completed scene and Oak's removal survive reload without replay.
    world.restore(world.save());
    expect(settle(world)).toEqual([]);
    expect(world.objects().some((object) => object.id === 3)).toBe(false);
    world.interact();
    expect(settle(world).join("\n")).toContain("depending on");
    expect(world.state.bag.keyItems).toEqual([EGG]);
  });

  it("reloads during Oak's speech from committed state and replays rewards once", () => {
    const world = fixture();
    for (let tick = 0; tick < 3000; tick++) {
      if (world.dialogue?.pages[world.dialogue.index].includes("OAK: Aha")) break;
      if (world.dialogue) world.advanceDialogue();
      else world.tick();
    }
    expect(world.dialogue?.pages[world.dialogue.index]).toContain("OAK: Aha");
    const saved = world.save();
    expect(saved.bag.keyItems).toEqual([]);
    expect(saved.events).not.toContain(30);
    world.restore(saved);
    expect(settle(world).join("\n")).toContain("MYSTERY EGG");
    expect(world.notice, world.diagnostic).toBe("");
    expect(world.state.bag.keyItems).toEqual([EGG]);
  });

  it("rolls back rewards, healing and Oak's departure when a late command is refused", () => {
    const world = fixture(155, true);
    const before = world.save();
    for (let tick = 0; tick < 5000 && !world.notice; tick++) {
      if (world.dialogue) world.advanceDialogue();
      else world.tick();
    }
    expect(world.notice).toContain("not been ported");
    expect(world.state.bag.keyItems).toEqual([]);
    expect(world.state.party[0]).toEqual(before.party[0]);
    expect(world.state.events.has(30)).toBe(false);
    expect(world.state.events.has(1737)).toBe(false);
    expect(world.state.lastSpawnMap).toBe(before.lastSpawnMap);
    expect(world.state.flags.has(11)).toBe(false);
    expect(world.objects().find((object) => object.id === 3)).toMatchObject({ x: 6, y: 5 });
    expect(world.save()).toMatchObject({ x: before.x, y: before.y });
  });
});

describe.skipIf(!existsSync(romPath))("Cherrygrove's first rival battle with the local ROM", () => {
  const RIVAL = 3; // CHERRYGROVECITY_RIVAL, after the Guide Gent
  let assets: CrystalAssets;
  beforeAll(() => {
    assets = new CrystalAssets(new Uint8Array(readFileSync(romPath)));
  });
  /** Play through scripts and battles, fighting with the first move. */
  const drive = (world: GameWorld) => {
    const shown: string[] = [];
    for (let tick = 0; tick < 50_000; tick++) {
      const view = world.battle;
      if (view) {
        if (view.message && shown.at(-1) !== view.message.text) shown.push(view.message.text);
        if (view.prompt?.kind === "action") world.battleAction({ action: "fight", move: 0 });
        else if (view.prompt?.kind === "stats" || view.message?.prompt) world.interact();
        else world.tick();
        continue;
      }
      if (world.dialogue) {
        shown.push(world.dialogue.pages[world.dialogue.index]);
        if (world.dialogue.holdTicks !== undefined) world.tick();
        else world.advanceDialogue();
        continue;
      }
      if (!world.busy) return shown.join("\n");
      world.tick();
    }
    throw new Error(`The world did not settle: ${world.diagnostic}`);
  };

  // loadtrainer RIVAL1, RIVAL1_1_<the starter Elm kept>.
  it.each([[158, 152], [152, 155], [155, 158]])("with starter %i, battles the rival's %i and commits the exit", (species, rivalSpecies) => {
    const world = questRivalFixtureWorld(assets, species);
    const money = world.state.money;
    expect(world.move("right")).toBe(true);
    const shown = drive(world);
    expect(world.notice, world.diagnostic).toBe("");
    // TrainerClassNames' "RIVAL" and Rival1Group's placeholder name "?".
    expect(shown).toContain("RIVAL ?\nwas defeated!");
    expect(shown).toContain("My name's ???.");
    expect(world.state.pokedex.seen.has(rivalSpecies)).toBe(true);
    expect(world.state.money).toBe(money + 300);
    expect(world.state.scenes["26:3"]).toBe(0); // SCENE_CHERRYGROVECITY_NOOP
    expect(world.objects().some((object) => object.id === RIVAL)).toBe(false);
    const mon = world.state.party[0];
    expect(mon.hp).toBe(mon.stats[0]);
    // The finished scene does not replay after reload.
    world.restore(world.save());
    expect(drive(world)).toBe("");
    expect(world.objects().some((object) => object.id === RIVAL)).toBe(false);
  });

  it("runs CherrygroveRivalSceneNorth from the east as well", () => {
    const world = questRivalFixtureWorld(assets);
    world.restore({ ...world.save(), x: 34, y: 6, direction: "left" });
    expect(world.move("left")).toBe(true);
    expect(drive(world)).toContain("RIVAL ?\nwas defeated!");
    expect(world.notice, world.diagnostic).toBe("");
    expect(world.state.scenes["26:3"]).toBe(0);
    expect(world.objects().some((object) => object.id === RIVAL)).toBe(false);
    world.restore(world.save());
  });

  it("continues the scene after a loss without whiting out (BATTLETYPE_CANLOSE)", () => {
    const world = questRivalFixtureWorld(assets);
    const mon = world.state.party[0];
    mon.hp = 1;
    mon.moves = [43, 0, 0, 0]; // Leer cannot win.
    mon.pp = [30, 0, 0, 0];
    const money = world.state.money;
    expect(world.move("right")).toBe(true);
    const shown = drive(world);
    expect(world.notice, world.diagnostic).toBe("");
    expect(shown).toContain("fainted!");
    expect(shown).toContain("waste of time");
    expect(world.mapId).toBe("26:3");
    expect(world.state.money).toBe(money);
    expect(world.state.scenes["26:3"]).toBe(0);
    expect(world.state.party[0].hp).toBe(world.state.party[0].stats[0]);
  });
});

describe.skipIf(!existsSync(romPath))("Elm's robbed call with the local ROM", () => {
  const ELM_CALLED = 67; // EVENT_ELM_CALLED_ABOUT_STOLEN_POKEMON
  let assets: CrystalAssets;
  beforeAll(() => {
    assets = new CrystalAssets(new Uint8Array(readFileSync(romPath)));
  });
  const afterHouse = () => {
    const world = questFixtureWorld(assets);
    expect(world.move("up")).toBe(true);
    settle(world);
    expect(world.state.specialPhoneCall).toBe(2); // SPECIALCALL_ROBBED
    return world;
  };

  it("waits indoors, then rings on the next outdoor step and ends with the hang-up", () => {
    const world = afterHouse();
    // SpecialCallOnlyWhenOutside: a step inside the house does not ring.
    expect(world.move("left") || world.move("right")).toBe(true);
    expect(settle(world)).toEqual([]);
    expect(world.state.specialPhoneCall).toBe(2);
    world.restore({ ...world.save(), map: "26:1", x: 17, y: 8, direction: "down", objects: [] });
    expect(world.move("down")).toBe(true);
    const pages = settle(world);
    expect(world.notice, world.diagnostic).toBe("");
    expect(pages[0]).toContain("It's a disaster!");
    // HangUp: "Click!", then Phone_CallEnd's boops.
    expect(pages.slice(-2)).toEqual(["Click!", "……"]);
    expect(world.state.specialPhoneCall).toBe(0);
    expect(world.state.events.has(ELM_CALLED)).toBe(true);
    world.restore(world.save());
    expect(world.move("down")).toBe(true);
    expect(settle(world)).toEqual([]);
  });

  it("replays the whole call after a reload mid-call, from the committed step", () => {
    const world = afterHouse();
    world.restore({ ...world.save(), map: "26:1", x: 17, y: 8, direction: "down", objects: [] });
    expect(world.move("down")).toBe(true);
    for (let tick = 0; tick < 500 && !world.dialogue; tick++) world.tick();
    expect(world.dialogue?.pages[0]).toContain("disaster");
    const saved = world.save();
    expect(saved.specialPhoneCall).toBe(2);
    expect(saved.events).not.toContain(ELM_CALLED);
    expect(saved).toMatchObject({ x: 17, y: 8 });
    world.restore(saved);
    expect(world.move("down")).toBe(true);
    expect(settle(world).slice(-2)).toEqual(["Click!", "……"]);
    expect(world.state.specialPhoneCall).toBe(0);
  });
});

describe.skipIf(!existsSync(romPath))("the return to Elm's lab with the local ROM", () => {
  const LAB = "24:5", OFFICER = 7, ELM = 2; // ELMSLAB_OFFICER, ELMSLAB_ELM
  let assets: CrystalAssets;
  beforeAll(() => {
    assets = new CrystalAssets(new Uint8Array(readFileSync(romPath)));
  });
  /** Enter the lab and step onto MeetCopScript's tile, answering the naming screen. */
  const meetOfficer = (name: string) => {
    const world = questLabFixtureWorld(assets);
    expect(world.move("up")).toBe(true);
    expect(world.mapId).toBe(LAB);
    walkTo(world, 4, 6);
    expect(world.move("up")).toBe(true);
    return { world, pages: settle(world, [name]) };
  };

  it("names the rival on the naming screen and remembers it across reload", () => {
    const { world, pages } = meetOfficer("BLUE");
    expect(world.notice, world.diagnostic).toBe("");
    expect(pages).toContain("RIVAL'S NAME?");
    expect(pages).toContain("OK! So BLUE\nwas his name.");
    expect(world.state.rivalName).toBe("BLUE");
    expect(world.state.scenes[LAB]).toBe(2); // SCENE_ELMSLAB_NOOP
    expect(world.objects().some((object) => object.id === OFFICER)).toBe(false);
    world.restore(world.save());
    expect(world.state.rivalName).toBe("BLUE");
    expect(world.objects().some((object) => object.id === OFFICER)).toBe(false);
  });

  it.each(["", "   "])("InitName gives the blank name %j the ROM default", (name) => {
    const { world, pages } = meetOfficer(name);
    expect(world.notice, world.diagnostic).toBe("");
    expect(world.state.rivalName).toBe("SILVER");
    expect(pages).toContain("OK! So SILVER\nwas his name.");
  });

  it("replays the officer scene from the committed step after a reload at the naming screen", () => {
    const world = questLabFixtureWorld(assets);
    world.move("up");
    walkTo(world, 4, 6);
    world.move("up");
    expect(settle(world)).toContain("RIVAL'S NAME?"); // waits: no name queued
    const saved = world.save();
    expect(saved.rivalName).toBe("???");
    expect(saved).toMatchObject({ x: 4, y: 6 });
    world.restore(saved);
    expect(world.move("up")).toBe(true);
    settle(world, ["GARY"]);
    expect(world.state.rivalName).toBe("GARY");
  });

  it("hands the Egg to Elm, then the aide gives five Poké Balls", () => {
    const { world } = meetOfficer("BLUE");
    walkTo(world, 5, 3);
    world.move("up"); // Elm stands at 5,2: this only turns the player.
    world.interact();
    const elm = settle(world).join("\n");
    expect(world.notice, world.diagnostic).toBe("");
    expect(elm).toContain("handed\nthe MYSTERY EGG");
    expect(world.state.bag.keyItems).toEqual([]);
    expect(world.state.scenes[LAB]).toBe(6); // SCENE_ELMSLAB_AIDE_GIVES_POKE_BALLS
    expect(world.state.scenes["24:3"]).toBe(1); // SCENE_ROUTE29_CATCH_TUTORIAL
    const aide = walkTo(world, 4, 8).join("\n");
    expect(world.notice, world.diagnostic).toBe("");
    expect(aide).toContain("received\nPOKé BALL.");
    expect(world.state.bag.balls).toEqual([{ item: 5, quantity: 5 }]); // POKE_BALL
    world.restore(world.save());
    expect(world.state.bag.balls).toEqual([{ item: 5, quantity: 5 }]);
    expect(world.objects().some((object) => object.id === ELM)).toBe(true);
  });
});