import { mkdir, mkdtemp, readdir, rm, symlink, writeFile } from "node:fs/promises";
import { tmpdir } from "node:os";
import path from "node:path";
import type { PrismaClient } from "@rakazo/db";
import { afterEach, describe, expect, it, vi } from "vitest";
import {
  ExpoPushSender,
  expoPushErrorMessage,
  importLegacyPushTokens,
  legacyPushTokenDir,
  MAX_EXPO_PUSH_RESPONSE_BYTES,
} from "./expo-push.js";
import type { PushPayload } from "./push-notifications.js";

const dirs: string[] = [];

afterEach(async () => {
  vi.unstubAllGlobals();
  await Promise.all(dirs.splice(0).map((dir) => rm(dir, { recursive: true, force: true })));
});

const device = { endpoint: "ExponentPushToken[test]", p256dh: null, auth: null };

function payload(overrides: Partial<PushPayload> = {}): PushPayload {
  return {
    kind: "completion",
    title: "done",
    body: "ok",
    botId: "b",
    threadId: "t",
    url: "/app/b",
    ...overrides,
  };
}

function jsonResponse(body: unknown, status = 200) {
  return Response.json(body, { status });
}

describe("expo push tickets", () => {
  it("reads a single Expo ticket and a ticket array", () => {
    expect(expoPushErrorMessage({ data: { status: "ok", id: "1" } }, 200)).toBeUndefined();
    expect(expoPushErrorMessage({ data: { status: "error", message: "bad token" } }, 200)).toBe(
      "bad token",
    );
    expect(expoPushErrorMessage({ errors: [{ message: "rate limited" }] }, 429)).toBe(
      "rate limited",
    );
    expect(expoPushErrorMessage(undefined, 502)).toBe("expo push failed (502)");
    expect(
      expoPushErrorMessage(
        { data: { status: "error", details: { error: "DeviceNotRegistered" } } },
        200,
      ),
    ).toBe("DeviceNotRegistered");
  });
});

describe("expo push sender", () => {
  it("posts the notification to Expo for the device token", async () => {
    const fetchMock = vi
      .fn()
      .mockResolvedValue(jsonResponse({ data: { status: "ok", id: "ticket" } }));
    vi.stubGlobal("fetch", fetchMock);
    await expect(
      new ExpoPushSender().send(
        device,
        payload({
          kind: "takeover",
          title: "Need you",
          body: "on screen",
          botId: "bot-1",
          threadId: "th-1",
        }),
      ),
    ).resolves.toBe("sent");
    expect(fetchMock).toHaveBeenCalledOnce();
    const [url, init] = fetchMock.mock.calls[0] as [string, RequestInit];
    expect(url).toBe("https://exp.host/--/api/v2/push/send");
    const body = JSON.parse(String(init.body)) as {
      to: string;
      title: string;
      collapseId: string;
      tag: string;
      data: { kind: string; botId: string; threadId: string };
    };
    expect(body).toMatchObject({
      to: "ExponentPushToken[test]",
      title: "Need you",
      collapseId: "th-1",
      tag: "th-1",
      data: { kind: "takeover", botId: "bot-1", threadId: "th-1" },
    });
  });

  it("reports a device Expo no longer knows as gone", async () => {
    vi.stubGlobal(
      "fetch",
      vi
        .fn()
        .mockResolvedValue(
          jsonResponse({ data: { status: "error", details: { error: "DeviceNotRegistered" } } }),
        ),
    );
    await expect(new ExpoPushSender().send(device, payload())).resolves.toBe("gone");
  });

  it("throws when Expo rejects the request", async () => {
    vi.stubGlobal(
      "fetch",
      vi.fn().mockResolvedValue(jsonResponse({ errors: [{ message: "boom" }] }, 500)),
    );
    await expect(new ExpoPushSender().send(device, payload())).rejects.toThrow("boom");
  });

  it("rejects and cancels a declared oversized response", async () => {
    const response = new Response("oversized", {
      headers: { "content-length": String(MAX_EXPO_PUSH_RESPONSE_BYTES + 1) },
    });
    const cancel = vi.spyOn(response.body!, "cancel");
    vi.stubGlobal("fetch", vi.fn().mockResolvedValue(response));

    await expect(new ExpoPushSender().send(device, payload())).rejects.toThrow(
      "Expo push response is too large.",
    );
    expect(cancel).toHaveBeenCalledOnce();
  });

  it("does not wait past cancellation when an oversized body cancel hangs", async () => {
    let cancelStarted = false;
    const hangingBody = new ReadableStream<Uint8Array>({
      cancel() {
        cancelStarted = true;
        return new Promise(() => undefined);
      },
    });
    const abort = new AbortController();
    vi.stubGlobal(
      "fetch",
      vi.fn(async () => {
        setTimeout(() => abort.abort(), 20);
        return new Response(hangingBody, {
          headers: { "content-length": String(MAX_EXPO_PUSH_RESPONSE_BYTES + 1) },
        });
      }),
    );

    const started = Date.now();
    await expect(new ExpoPushSender().send(device, payload(), abort.signal)).rejects.toThrow(
      "Expo push response is too large.",
    );
    expect(cancelStarted).toBe(true);
    expect(Date.now() - started).toBeLessThan(500);
  });

  it("caps a streamed response without a content length", async () => {
    vi.stubGlobal(
      "fetch",
      vi.fn().mockResolvedValue(new Response(new Uint8Array(MAX_EXPO_PUSH_RESPONSE_BYTES + 1))),
    );
    await expect(new ExpoPushSender().send(device, payload())).rejects.toThrow(
      "Expo push response is too large.",
    );
  });

  it("rejects malformed successful responses", async () => {
    vi.stubGlobal("fetch", vi.fn().mockResolvedValue(new Response("not json")));
    await expect(new ExpoPushSender().send(device, payload())).rejects.toThrow(
      "Expo push returned an invalid response.",
    );
  });

  it("passes caller cancellation to the Expo request", async () => {
    const controller = new AbortController();
    controller.abort(new Error("notification cancelled"));
    const fetchMock = vi.fn(async (_url: string, init?: RequestInit) => {
      expect(init?.signal?.aborted).toBe(true);
      throw init?.signal?.reason;
    });
    vi.stubGlobal("fetch", fetchMock);

    await expect(new ExpoPushSender().send(device, payload(), controller.signal)).rejects.toThrow(
      "notification cancelled",
    );
    expect(fetchMock).toHaveBeenCalledOnce();
  });

  it("throws when the Expo request never reaches the network", async () => {
    vi.stubGlobal("fetch", vi.fn().mockRejectedValue(new Error("offline")));
    await expect(new ExpoPushSender().send(device, payload())).rejects.toThrow("offline");
  });
});

describe("legacy push token import", () => {
  function fakePrisma(existingUsers: string[]) {
    const upsert = vi.fn().mockResolvedValue({});
    const prisma = {
      user: {
        findUnique: vi.fn(async ({ where }: { where: { id: string } }) =>
          existingUsers.includes(where.id) ? { id: where.id } : null,
        ),
      },
      pushSubscription: {
        upsert,
        findMany: vi.fn().mockResolvedValue([]),
        deleteMany: vi.fn().mockResolvedValue({ count: 0 }),
      },
    } as unknown as PrismaClient;
    return { prisma, upsert };
  }

  it("imports each token once, skips unknown users and removes the files", async () => {
    const dataDir = await mkdtemp(path.join(tmpdir(), "rakazo-push-"));
    dirs.push(dataDir);
    const dir = legacyPushTokenDir(dataDir);
    await mkdir(dir, { recursive: true });
    await writeFile(path.join(dir, "user-1.txt"), "ExponentPushToken[one]\n");
    await writeFile(path.join(dir, "gone-user.txt"), "ExponentPushToken[two]");
    await writeFile(path.join(dir, "user-2.txt"), "not a token");
    const { prisma, upsert } = fakePrisma(["user-1", "user-2"]);

    await expect(importLegacyPushTokens(prisma, dataDir)).resolves.toBe(1);

    expect(upsert).toHaveBeenCalledOnce();
    expect(upsert.mock.calls[0]![0]).toMatchObject({
      where: { endpoint: "ExponentPushToken[one]" },
      create: { endpoint: "ExponentPushToken[one]", userId: "user-1", kind: "expo" },
    });
    await expect(readdir(dataDir)).resolves.toEqual([]);
    await expect(importLegacyPushTokens(prisma, dataDir)).resolves.toBe(0);
  });

  it("does not follow a token-file symlink", async () => {
    const dataDir = await mkdtemp(path.join(tmpdir(), "rakazo-push-"));
    dirs.push(dataDir);
    const dir = legacyPushTokenDir(dataDir);
    await mkdir(dir, { recursive: true });
    const outside = path.join(dataDir, "outside.txt");
    await writeFile(outside, "ExponentPushToken[outside]");
    await symlink(outside, path.join(dir, "user-1.txt"));
    const { prisma, upsert } = fakePrisma(["user-1"]);

    await expect(importLegacyPushTokens(prisma, dataDir)).resolves.toBe(0);
    expect(upsert).not.toHaveBeenCalled();
    await expect(readdir(dataDir)).resolves.toEqual(["outside.txt"]);
  });
});