import { describe, expect, it } from "vitest";
import { createActor, fromPromise, waitFor } from "xstate";

import {
  PrivateAlbumsResponse,
  PrivateAlbumUnlockResponse,
} from "@/data/dto/private-room";
import { privateRoomMachine } from "@/stores/private-room/private-room-machine";

const ALBUM_ID = "a1b2c3d4-0000-0000-0000-000000000000";
const COVER_URL =
  "https://dbapi.banlv-ai.com/storage/v1/object/public/elio-schedules/01.jpg";

function makeAlbum(index = 0) {
  return {
    albumId: index === 0 ? ALBUM_ID : `album-${index}`,
    title: `Private album ${index + 1}`,
    content: null,
    previewText: "Only for you.",
    imageCount: 8,
    images: [{ url: `${COVER_URL}?album=${index}`, locked: true, index: 0 }],
    locked: true,
    unlocked: false,
    unlockCost: 320,
    publishedAt: "2026-07-13T00:00:00+00:00",
    lockDetail: { locked: true },
  };
}

function makeAlbumsResponse(
  overrides: Partial<Parameters<typeof PrivateAlbumsResponse.from>[0]> = {},
): PrivateAlbumsResponse {
  return PrivateAlbumsResponse.from({
    items: [makeAlbum()],
    creditBalance: 500,
    ...overrides,
  });
}

function makeUnlockResponse(
  overrides: Partial<Parameters<typeof PrivateAlbumUnlockResponse.from>[0]> = {},
): PrivateAlbumUnlockResponse {
  return PrivateAlbumUnlockResponse.from({
    albumId: ALBUM_ID,
    locked: false,
    unlocked: true,
    reason: "ok",
    unlockCost: 320,
    requiredCredits: 320,
    creditBalance: 180,
    shortfallCredits: 0,
    images: Array.from({ length: 8 }, (_, index) => ({
      url: `${COVER_URL}?image=${index}`,
      locked: false,
      index,
    })),
    ...overrides,
  });
}

function createTestMachine(options: {
  loadResponse?: PrivateAlbumsResponse;
  unlockResponse?: PrivateAlbumUnlockResponse;
  onLoad?: () => void;
} = {}) {
  return privateRoomMachine.provide({
    actors: {
      loadAlbums: fromPromise(async () => {
        options.onLoad?.();
        return options.loadResponse ?? makeAlbumsResponse();
      }),
      unlockAlbum: fromPromise(async () =>
        (options.unlockResponse ?? makeUnlockResponse()),
      ),
    },
  });
}

async function loadMachine(options: Parameters<typeof createTestMachine>[0] = {}) {
  const actor = createActor(createTestMachine(options)).start();
  actor.send({ type: "PrivateRoomInit" });
  await waitFor(actor, (snapshot) => snapshot.matches("ready"));
  return actor;
}

async function unlockFirstAlbum(
  actor: Awaited<ReturnType<typeof loadMachine>>,
) {
  actor.send({
    type: "PrivateRoomUnlockRequested",
    albumId: ALBUM_ID,
  });
  actor.send({ type: "PrivateRoomUnlockConfirmed" });
  await waitFor(actor, (snapshot) => snapshot.matches("ready"));
}

describe("privateRoomMachine", () => {
  it("loads only the first album page into its non-paginated state", async () => {
    const actor = await loadMachine({
      loadResponse: makeAlbumsResponse({
        items: Array.from({ length: 20 }, (_, index) => makeAlbum(index)),
      }),
    });
    const context = actor.getSnapshot().context;

    expect(context.items).toHaveLength(20);
    expect(context.creditBalance).toBe(500);
    expect(context).not.toHaveProperty("hasMore");
    expect(context).not.toHaveProperty("nextCursor");
    actor.stop();
  });

  it("patches the album images after a successful unlock", async () => {
    const actor = await loadMachine();
    await unlockFirstAlbum(actor);
    const context = actor.getSnapshot().context;

    expect(context.items[0]).toMatchObject({
      albumId: ALBUM_ID,
      locked: false,
      unlocked: true,
      title: "Private album 1",
    });
    expect(context.items[0]?.images).toHaveLength(8);
    expect(context.items[0]?.lockDetail).toEqual({ locked: false });
    expect(context.unlockSuccessNonce).toBe(1);
    actor.stop();
  });

  it("keeps the album locked and exposes a paywall request when credits are low", async () => {
    const actor = await loadMachine({
      unlockResponse: makeUnlockResponse({
        locked: true,
        unlocked: false,
        reason: "insufficient_credits",
        creditBalance: 100,
        shortfallCredits: 220,
        images: [{ url: COVER_URL, locked: true, index: 0 }],
      }),
    });
    await unlockFirstAlbum(actor);
    const context = actor.getSnapshot().context;

    expect(context.items[0]?.locked).toBe(true);
    expect(context.unlockPaywallRequest).toEqual({
      albumId: ALBUM_ID,
      reason: "insufficient_credits",
      requiredCredits: 320,
      currentCredits: 100,
      shortfallCredits: 220,
    });
    actor.stop();
  });

  it("reloads the first page when the expected cost changed", async () => {
    let loadCount = 0;
    const actor = await loadMachine({
      onLoad: () => {
        loadCount += 1;
      },
      unlockResponse: makeUnlockResponse({
        locked: true,
        unlocked: false,
        reason: "cost_changed",
      }),
    });
    await unlockFirstAlbum(actor);

    expect(loadCount).toBe(2);
    expect(actor.getSnapshot().context.unlockErrorMessage).toBe(
      "Unlock price changed. Please confirm again.",
    );
    actor.stop();
  });

  it("removes an album that no longer exists", async () => {
    const actor = await loadMachine({
      unlockResponse: makeUnlockResponse({
        locked: true,
        unlocked: false,
        reason: "not_found",
        images: [],
      }),
    });
    await unlockFirstAlbum(actor);

    expect(actor.getSnapshot().context.items).toHaveLength(0);
    actor.stop();
  });

  it("keeps a refunded persistence failure locked and updates the balance", async () => {
    const actor = await loadMachine({
      unlockResponse: makeUnlockResponse({
        locked: true,
        unlocked: false,
        reason: "persist_failed_refunded",
        creditBalance: 500,
        images: [{ url: COVER_URL, locked: true, index: 0 }],
      }),
    });
    await unlockFirstAlbum(actor);
    const context = actor.getSnapshot().context;

    expect(context.items[0]?.locked).toBe(true);
    expect(context.creditBalance).toBe(500);
    expect(context.unlockErrorMessage).toContain("refunded");
    actor.stop();
  });
});