import { describe, it, expect, beforeEach, afterEach } from "vitest";
import { mkdtempSync, rmSync } from "node:fs";
import { tmpdir } from "node:os";
import { join } from "node:path";
import { MailboxStore } from "../src/db.js";

let dir: string;
let store: MailboxStore;

beforeEach(() => {
  dir = mkdtempSync(join(tmpdir(), "claude-mailbox-wait-"));
  store = new MailboxStore(join(dir, "test.db"));
});

afterEach(() => {
  store.close();
  rmSync(dir, { recursive: true, force: true });
});

describe("MailboxStore.waitForMessage", () => {
  it("returns an already-pending message immediately", async () => {
    store.upsertMailbox("alice");
    store.upsertMailbox("bob");
    store.send("alice", "bob", "hello");

    const ac = new AbortController();
    const result = await store.waitForMessage("bob", 1000, ac.signal);
    expect(result.kind).toBe("message");
    if (result.kind === "message") {
      expect(result.message.body).toBe("hello");
      expect(result.message.from_mailbox).toBe("alice");
      expect(result.message.delivered_at).not.toBeNull();
    }
  });

  it("blocks until a message arrives, then resolves", async () => {
    store.upsertMailbox("alice");
    store.upsertMailbox("bob");

    const ac = new AbortController();
    const pending = store.waitForMessage("bob", 5000, ac.signal);

    setTimeout(() => store.send("alice", "bob", "later"), 50);

    const result = await pending;
    expect(result.kind).toBe("message");
    if (result.kind === "message") expect(result.message.body).toBe("later");
  });

  it("resolves with timeout when nothing arrives", async () => {
    store.upsertMailbox("bob");
    const ac = new AbortController();
    const result = await store.waitForMessage("bob", 80, ac.signal);
    expect(result.kind).toBe("timeout");
  });

  it("resolves with aborted when the signal fires", async () => {
    store.upsertMailbox("bob");
    const ac = new AbortController();
    const pending = store.waitForMessage("bob", 5000, ac.signal);
    setTimeout(() => ac.abort(), 30);
    const result = await pending;
    expect(result.kind).toBe("aborted");
  });

  it("resolves with renamed when the mailbox is renamed mid-wait", async () => {
    store.upsertMailbox("oldname");
    const ac = new AbortController();
    const pending = store.waitForMessage("oldname", 5000, ac.signal);
    setTimeout(() => store.rename("oldname", "newname"), 30);
    const result = await pending;
    expect(result.kind).toBe("renamed");
    if (result.kind === "renamed") expect(result.to).toBe("newname");
  });

  it("FIFO single-delivery: two waiters, one send, only the first gets the message", async () => {
    store.upsertMailbox("alice");
    store.upsertMailbox("bob");

    const ac1 = new AbortController();
    const ac2 = new AbortController();
    const w1 = store.waitForMessage("bob", 5000, ac1.signal);
    // Stagger so w1 registers first.
    await new Promise((r) => setTimeout(r, 10));
    const w2 = store.waitForMessage("bob", 200, ac2.signal);

    store.send("alice", "bob", "for-w1");

    const [r1, r2] = await Promise.all([w1, w2]);
    expect(r1.kind).toBe("message");
    if (r1.kind === "message") expect(r1.message.body).toBe("for-w1");
    expect(r2.kind).toBe("timeout");
  });

  it("two pending messages are drained by two reconnecting waiters", async () => {
    store.upsertMailbox("alice");
    store.upsertMailbox("bob");
    store.send("alice", "bob", "m1");
    store.send("alice", "bob", "m2");

    const ac = new AbortController();
    const r1 = await store.waitForMessage("bob", 1000, ac.signal);
    const r2 = await store.waitForMessage("bob", 1000, ac.signal);
    expect(r1.kind).toBe("message");
    expect(r2.kind).toBe("message");
    if (r1.kind === "message" && r2.kind === "message") {
      expect([r1.message.body, r2.message.body]).toEqual(["m1", "m2"]);
    }
  });

  it("abort racing send: message is either delivered or remains pending, never lost", async () => {
    store.upsertMailbox("alice");
    store.upsertMailbox("bob");

    const ac = new AbortController();
    const pending = store.waitForMessage("bob", 5000, ac.signal);

    // Fire abort and send in the same tick — either order is valid as long as the message is never lost.
    ac.abort();
    store.send("alice", "bob", "racy");

    const r = await pending;
    if (r.kind === "aborted") {
      // Message must still be in DB for the next caller.
      expect(store.peek("bob").pending).toBe(1);
    } else if (r.kind === "message") {
      expect(r.message.body).toBe("racy");
      expect(store.peek("bob").pending).toBe(0);
    } else {
      throw new Error(`unexpected kind: ${r.kind}`);
    }
  });

  it("rejectAllWaiters resolves every pending waiter as aborted and empties the bucket map", async () => {
    store.upsertMailbox("bob");
    store.upsertMailbox("carol");

    const ac1 = new AbortController();
    const ac2 = new AbortController();
    const ac3 = new AbortController();
    const w1 = store.waitForMessage("bob", 5000, ac1.signal);
    const w2 = store.waitForMessage("bob", 5000, ac2.signal);
    const w3 = store.waitForMessage("carol", 5000, ac3.signal);

    // Give all three a chance to register their waiters.
    await new Promise((r) => setTimeout(r, 10));

    store.rejectAllWaiters();

    const [r1, r2, r3] = await Promise.all([w1, w2, w3]);
    expect(r1.kind).toBe("aborted");
    expect(r2.kind).toBe("aborted");
    expect(r3.kind).toBe("aborted");
  });
});