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

const romPath =
  process.env.CRYSTAL_ROM_PATH ??
  "Pokemon - Crystal Version (UE) (V1.1) [C][!].gbc";
const BERRY = 0xad;
const ROUTE_29 = "24:3";

describe.skipIf(!existsSync(romPath))("Route 29 with the local ROM", () => {
  /** `now` is mutable per test. */
  const fixture = (date = "2026-09-22T12:00:00") => {
    const assets = new CrystalAssets(new Uint8Array(readFileSync(romPath)));
    const clock = { now: new Date(date) };
    const world = new GameWorld(assets, () => clock.now);
    // Facing FRUITTREE_ROUTE_29 at (12, 2).
    world.restore({ ...world.save(), map: ROUTE_29, x: 12, y: 3, direction: "up" });
    world.tick();
    return { world, clock };
  };
  const berries = (world: GameWorld) =>
    world.state.bag.items.find((slot) => slot.item === BERRY)?.quantity ?? 0;
  const pick = (world: GameWorld) => {
    world.interact();
    const pages = settle(world);
    expect(world.notice, world.diagnostic).toBe("");
    return pages.join("\n");
  };

  it("picks a Berry once per day and regrows after the daily reset", () => {
    const { world, clock } = fixture();
    expect(world.state.dailyReset).not.toBeNull();
    expect(pick(world)).toMatch(/BERRY/);
    expect(berries(world)).toBe(1);
    expect(world.state.fruitTrees).toEqual(new Set([1]));
    expect(world.state.flags.has(ENGINE_FLAGS.allFruitTrees)).toBe(true);

    // Same day, even across a save and reload: nothing to pick.
    const saved = world.save();
    expect(saved).toMatchObject({ fruitTrees: [1] });
    world.restore(saved);
    expect(world.save()).toEqual(saved);
    pick(world);
    expect(berries(world)).toBe(1);

    // The first idle tick of the next day clears the daily flag.
    clock.now = new Date("2026-09-23T00:01:00");
    world.tick();
    expect(world.state.flags.has(ENGINE_FLAGS.allFruitTrees)).toBe(false);
    expect(pick(world)).toMatch(/BERRY/);
    expect(berries(world)).toBe(2);
  });

  it("leaves the tree unpicked when the item pocket is full", () => {
    const { world } = fixture();
    world.state.bag.items = Array.from({ length: 20 }, (_, index) => ({
      item: index + 1,
      quantity: 1,
    }));
    const before = world.state.bag.items.map((slot) => ({ ...slot }));
    pick(world);
    expect(world.state.bag.items).toEqual(before);
    expect(world.state.fruitTrees.size).toBe(0);
  });

  it("migrates version-3 saves without daily state and rejects invalid trees", () => {
    const { world } = fixture();
    const { fruitTrees: _, dailyReset: __, ...legacy } = world.save();
    expect(migrateSave(legacy, () => 0)).toMatchObject({
      fruitTrees: [],
      dailyReset: null,
    });
    expect(() => world.restore({ ...world.save(), fruitTrees: [0] })).toThrow(
      "Invalid native save",
    );
    expect(() => world.restore({ ...world.save(), fruitTrees: [1, 1] })).toThrow(
      "Invalid native save",
    );
  });

  it("walks from New Bark Town across Route 29 into Cherrygrove and a house", () => {
    const assets = new CrystalAssets(new Uint8Array(readFileSync(romPath)));
    // Random byte 255 never passes an encounter-rate check.
    const world = new GameWorld(assets, () => new Date("2026-09-22T12:00:00"), () => 255);
    world.state.party.push(
      generatePartyMon(assets.pokemon, {
        species: 155, level: 5, item: 0, otId: world.playerId,
        ot: "CHRIS", dvs: 0x823b, caughtData: 0,
      }),
    );
    // After the starter, Elm sets SCENE_NEWBARKTOWN_NOOP: the teacher lets you go.
    world.restore({ ...world.save(), map: "24:4", x: 5, y: 8, scenes: { "24:4": 1 } });
    const crossWest = (next: string) => {
      const edge = Array.from({ length: world.map.height }, (_, y) => y).find((y) => {
        try {
          findPath(world, 0, y);
          return true;
        } catch {
          return false;
        }
      })!;
      walkTo(world, 0, edge);
      expect(world.move("left"), world.notice).toBe(true);
      settle(world);
      expect(world.mapId).toBe(next);
      expect(world.notice, world.diagnostic).toBe("");
    };
    crossWest(ROUTE_29);
    // Route29TuscanyCallback hides Tuscany without the Zephyr Badge, even on
    // a Tuesday (2026-09-22).
    expect(world.objects().some((object) => object.id === 8)).toBe(false);
    crossWest("26:3");
    walkTo(world, 17, 8);
    expect(world.move("up")).toBe(true);
    settle(world);
    expect(world.mapId).toBe("26:6");
    expect(world.notice, world.diagnostic).toBe("");
    const saved = world.save();
    world.restore(saved);
    expect(world.save()).toEqual(saved);
  });
});