import { describe, expect, it } from "vitest";
import { existsSync, readFileSync } from "node:fs";
import { CrystalAssets } from "../src/game/rom/assets";
import { C } from "../src/game/battle/constants";
import { martFixtureWorld, talkToClerk } from "./mart-fixture";
import { settle, withoutPlayTime } from "./world-driver";

const romPath = process.env.CRYSTAL_ROM_PATH ?? "Pokemon - Crystal Version (UE) (V1.1) [C][!].gbc";
const fixture = () => martFixtureWorld(new CrystalAssets(new Uint8Array(readFileSync(romPath))));

// constants/item_constants.asm
const POKE_BALL = 5,
  BICYCLE = 7,
  POTION = 18;

describe.skipIf(!existsSync(romPath))("Cherrygrove Mart with the local ROM", () => {
  it("buys Potions at the ROM price and adds them to the bag", () => {
    const world = fixture();
    const money = world.state.money;
    talkToClerk(world);
    // BUY -> Potion (list index 0) -> quantity 3 -> confirm YES -> back -> QUIT
    const shown = settle(world, [0, 0, 3, 1, -1, 2]);
    expect(world.notice, world.diagnostic).toBe("");
    expect(shown.join("\n")).toContain("Here you are");
    expect(world.state.money).toBe(money - 300 * 3);
    expect(world.state.bag.items).toEqual([{ item: POTION, quantity: 3 }]);
  });

  it("refuses to buy without enough money, changing nothing", () => {
    const world = fixture();
    world.state.money = 100; // less than one Potion (300)
    talkToClerk(world);
    const committed = world.save();
    const shown = settle(world, [0, 0, 1, 1, -1, 2]);
    expect(world.notice, world.diagnostic).toBe("");
    expect(shown.join("\n")).toMatch(/enough money/i);
    expect(withoutPlayTime(world.save())).toEqual(withoutPlayTime(committed));
  });

  it("refuses to buy into a full pocket, changing nothing", () => {
    const world = fixture();
    const data = world.assets.pokemon;
    const fillers: number[] = [];
    for (let id = 1; fillers.length < 20; id++) {
      if (id === POTION) continue;
      try {
        if (data.itemPocket(id) === "item") fillers.push(id);
      } catch {
        // Not every id names an item; skip gaps.
      }
    }
    world.state.bag.items = fillers.map((item) => ({ item, quantity: 1 }));
    talkToClerk(world);
    const committed = world.save();
    const shown = settle(world, [0, 0, 1, 1, -1, 2]);
    expect(world.notice, world.diagnostic).toBe("");
    expect(shown.join("\n")).toMatch(/can't carry/i);
    expect(withoutPlayTime(world.save())).toEqual(withoutPlayTime(committed));
  });

  it("sells items at half the ROM price", () => {
    const world = fixture();
    world.state.bag.items = [{ item: POTION, quantity: 5 }];
    talkToClerk(world);
    const money = world.state.money;
    // SELL -> Potion (index 0) -> quantity 2 -> confirm YES -> back -> QUIT
    const shown = settle(world, [1, 0, 2, 1, -1, 2]);
    expect(world.notice, world.diagnostic).toBe("");
    expect(shown.join("\n")).toContain("Got ¥300");
    expect(world.state.money).toBe(money + 300); // 300/2 * 2
    expect(world.state.bag.items).toEqual([{ item: POTION, quantity: 3 }]);
  });

  it("caps money at C.MAX_MONEY when selling", () => {
    const world = fixture();
    world.state.bag.items = [{ item: POTION, quantity: 1 }];
    world.state.money = C.MAX_MONEY - 10;
    talkToClerk(world);
    const shown = settle(world, [1, 0, 1, 1, -1, 2]);
    expect(world.notice, world.diagnostic).toBe("");
    expect(shown.join("\n")).not.toBe("");
    expect(world.state.money).toBe(C.MAX_MONEY);
    expect(world.state.bag.items).toEqual([]);
  });

  it("excludes key items from the sell list", () => {
    const world = fixture();
    world.state.bag.items = [{ item: POTION, quantity: 1 }];
    world.state.bag.keyItems = [BICYCLE];
    talkToClerk(world);
    world.choose(1); // SELL
    const choice = world.dialogue?.choice;
    expect(choice?.kind).toBe("martlist");
    if (choice?.kind === "martlist") {
      expect(choice.entries.map((entry) => entry.item)).toEqual([POTION]);
    }
  });

  it("sells a Poké Ball but refuses to sell key items or unaffordable buys together", () => {
    // MART_CHERRYGROVE_DEX stocks a Poké Ball once the mystery egg is given;
    // exercising a ball-pocket item confirms pockets beyond "item" work too.
    const world = fixture();
    world.state.events.add(31); // EVENT_GAVE_MYSTERY_EGG_TO_ELM
    talkToClerk(world);
    const money = world.state.money;
    // BUY -> Poké Ball (list index 0 in the dex mart) -> quantity 1 -> YES -> back -> QUIT
    settle(world, [0, 0, 1, 1, -1, 2]);
    expect(world.notice, world.diagnostic).toBe("");
    expect(world.state.money).toBe(money - 200);
    expect(world.state.bag.balls).toEqual([{ item: POKE_BALL, quantity: 1 }]);
  });

  it("quits immediately without changing state", () => {
    const world = fixture();
    const before = world.save();
    talkToClerk(world);
    settle(world, [2]);
    expect(world.notice, world.diagnostic).toBe("");
    expect(withoutPlayTime(world.save())).toEqual(withoutPlayTime(before));
  });

  it("a mid-interaction save restores the committed state and replays it", () => {
    const world = fixture();
    talkToClerk(world);
    const committed = world.save();
    world.choose(0); // BUY
    world.choose(0); // Potion -> quantity picker
    expect(world.dialogue?.choice?.kind).toBe("martquantity");
    expect(world.save()).toEqual(committed);
    world.restore(committed);
    expect(world.dialogue).toBeUndefined();
    expect(world.save()).toEqual(committed);
    // The world is usable again: a fresh visit still works.
    talkToClerk(world);
    expect(world.dialogue?.choice?.kind).toBe("martmenu");
  });
});