import { createPinia, setActivePinia } from "pinia";
import { beforeEach, describe, expect, it, vi } from "vitest";
import { flushPromises } from "@vue/test-utils";
import { api, useAuthStore } from "./auth";
import { useChatStore } from "./chat";
import type { Conversation } from "./chat";
import type { ChatMessage } from "./messages";

const socket = vi.hoisted(() => ({
  connected: false,
  on: vi.fn(),
  connect: vi.fn(),
  disconnect: vi.fn(),
}));

vi.mock("../api/socket", () => ({
  createChatSocket: () => socket,
  sendSocketMessage: vi.fn(),
}));

const me = {
  accountId: "a",
  publicId: "p",
  nickname: null,
  avatarColor: null,
  bio: null,
  profileReviewStatus: null,
};

function message(seq: number): ChatMessage {
  return {
    id: `m-${seq}`,
    conversationId: "c-1",
    sender: { publicId: "p" },
    clientMsgId: `client-${seq}`,
    seq: String(seq),
    text: String(seq),
    status: "sent",
    sentAt: new Date(seq).toISOString(),
  };
}

const conversation = (): Conversation => ({
  id: "c-1",
  status: "ACTIVE",
  lastMessageAt: new Date(0).toISOString(),
  lastMessage: null,
  unread: "0",
  lastReadSeq: "0",
});

beforeEach(() => {
  setActivePinia(createPinia());
  vi.restoreAllMocks();
  socket.connected = false;
  socket.disconnect.mockClear();
});

describe("chat history synchronization", () => {
  it("loads every page beyond 100 messages and reliably deduplicates overlap", async () => {
    const pages = [
      Array.from({ length: 100 }, (_, index) => message(index + 1)),
      Array.from({ length: 100 }, (_, index) => message(index + 100)),
      Array.from({ length: 51 }, (_, index) => message(index + 199)),
      [],
    ];
    const get = vi
      .spyOn(api, "get")
      .mockImplementation(() =>
        Promise.resolve({ items: pages.shift() ?? [] }),
      );
    const chat = useChatStore();

    const result = await chat.loadMessages("c-1");

    expect(result).toBeDefined();
    expect(result ?? []).toHaveLength(249);
    expect(result?.at(-1)?.seq).toBe("249");
    expect(get).toHaveBeenCalledTimes(3);
    expect(get.mock.calls.map(([path]) => path)).toEqual([
      "/conversations/c-1/messages?afterSeq=0&limit=100",
      "/conversations/c-1/messages?afterSeq=100&limit=100",
      "/conversations/c-1/messages?afterSeq=199&limit=100",
    ]);
  });

  it("stops paging after the page cap to bound waterfall requests", async () => {
    const pages = [
      Array.from({ length: 100 }, (_, index) => message(index + 1)),
      Array.from({ length: 100 }, (_, index) => message(index + 101)),
      Array.from({ length: 100 }, (_, index) => message(index + 201)),
      Array.from({ length: 100 }, (_, index) => message(index + 301)),
      Array.from({ length: 100 }, (_, index) => message(index + 401)),
      [],
    ];
    const get = vi
      .spyOn(api, "get")
      .mockImplementation(() =>
        Promise.resolve({ items: pages.shift() ?? [] }),
      );
    const chat = useChatStore();

    const result = await chat.loadMessages("c-1");

    expect(result ?? []).toHaveLength(500);
    expect(get.mock.calls.length).toBeLessThanOrEqual(5);
    expect(get.mock.calls.at(-1)?.[0]).toBe(
      "/conversations/c-1/messages?afterSeq=400&limit=100",
    );
  });

  it("syncs only the most recent active conversations when reconnecting", async () => {
    const get = vi.spyOn(api, "get").mockResolvedValue({ items: [] });
    const chat = useChatStore();
    chat.conversations = Array.from({ length: 30 }, (_, index) => {
      const id = `c-${index}`;
      return {
        id,
        status: "ACTIVE",
        lastMessageAt: new Date(1700000000000 + index).toISOString(),
        lastMessage: null,
        unread: "0",
        lastReadSeq: "0",
      };
    });

    await chat.syncAll();

    expect(
      get.mock.calls.filter(([path]) => path.includes("/messages")),
    ).toHaveLength(5);
    expect(
      get.mock.calls.filter(([path]) => path.includes("/messages"))[0]![0],
    ).toContain("c-29");
  });
});

describe("chat session lifecycle", () => {
  it("disconnects and clears account state when authentication ends", async () => {
    vi.spyOn(api, "post").mockResolvedValue({ accessToken: "fresh" });
    vi.spyOn(api, "get").mockResolvedValue(me);
    const auth = useAuthStore();
    await auth.login("13800000000", "123456", "device");
    expect(auth.isAuthenticated).toBe(true);
    const chat = useChatStore();
    chat.conversations = [conversation()];
    chat.messages = { "c-1": [message(1)] };
    expect(chat.conversations).toHaveLength(1);

    auth.me = null;

    await flushPromises();

    expect(auth.isAuthenticated).toBe(false);
    expect(socket.disconnect).toHaveBeenCalled();
    expect(chat.conversations).toEqual([]);
    expect(chat.messages).toEqual({});
    expect(chat.connected).toBe(false);
  });

  it("reset clears conversations and disconnects even when called directly", () => {
    const auth = useAuthStore();
    auth.me = me;
    const chat = useChatStore();
    chat.conversations = [conversation()];
    chat.messages = { "c-1": [message(1)] };

    chat.reset();

    expect(socket.disconnect).toHaveBeenCalled();
    expect(chat.conversations).toEqual([]);
    expect(chat.messages).toEqual({});
  });
});