import { expect, test } from "bun:test";
import {
  createAuthHeader,
  generateSecret,
  signMessage,
  verifyAuthHeader,
  verifySignature,
} from "./auth";

// Secret generation tests

test("generateSecret creates a 32-byte base64 secret", () => {
  const secret = generateSecret();

  // Base64 encoding of 32 bytes should be 44 characters (with padding)
  expect(secret.length).toBe(44);

  // Should be valid base64
  const decoded = Buffer.from(secret, "base64");
  expect(decoded.length).toBe(32);
});

test("generateSecret creates unique secrets", () => {
  const secret1 = generateSecret();
  const secret2 = generateSecret();
  const secret3 = generateSecret();

  expect(secret1).not.toBe(secret2);
  expect(secret2).not.toBe(secret3);
  expect(secret1).not.toBe(secret3);
});

// Sign/verify tests

test("signMessage creates a signature", async () => {
  const secret = generateSecret();
  const message = "test message";

  const signature = await signMessage(secret, message);

  expect(signature).toBeTruthy();
  expect(signature.length).toBeGreaterThan(0);
  // HMAC-SHA256 produces 32 bytes, base64 encoded is 44 chars
  expect(signature.length).toBe(44);
});

test("verifySignature succeeds with correct secret and message", async () => {
  const secret = generateSecret();
  const message = "test message";

  const signature = await signMessage(secret, message);
  const valid = await verifySignature(secret, message, signature);

  expect(valid).toBe(true);
});

test("verifySignature fails with wrong secret", async () => {
  const secret1 = generateSecret();
  const secret2 = generateSecret();
  const message = "test message";

  const signature = await signMessage(secret1, message);
  const valid = await verifySignature(secret2, message, signature);

  expect(valid).toBe(false);
});

test("verifySignature fails with wrong message", async () => {
  const secret = generateSecret();
  const message1 = "test message";
  const message2 = "different message";

  const signature = await signMessage(secret, message1);
  const valid = await verifySignature(secret, message2, signature);

  expect(valid).toBe(false);
});

test("verifySignature fails with tampered signature", async () => {
  const secret = generateSecret();
  const message = "test message";

  const signature = await signMessage(secret, message);
  // Tamper with the signature
  const tamperedSignature = `${signature.slice(0, -1)}X`;
  const valid = await verifySignature(secret, message, tamperedSignature);

  expect(valid).toBe(false);
});

test("verifySignature fails with invalid base64 signature", async () => {
  const secret = generateSecret();
  const message = "test message";

  const valid = await verifySignature(secret, message, "not-valid-base64!!!");

  expect(valid).toBe(false);
});

// Auth header tests

test("createAuthHeader creates header with timestamp and signature", async () => {
  const secret = generateSecret();
  const timestamp = Date.now();

  const header = await createAuthHeader(secret, timestamp);

  const parts = header.split(":");
  expect(parts.length).toBe(2);
  expect(parts[0]).toBe(timestamp.toString());
  expect(parts[1]?.length).toBe(44); // HMAC-SHA256 base64 length
});

test("verifyAuthHeader succeeds with valid header", async () => {
  const secret = generateSecret();
  const timestamp = Date.now();

  const header = await createAuthHeader(secret, timestamp);
  const valid = await verifyAuthHeader(secret, header);

  expect(valid).toBe(true);
});

test("verifyAuthHeader fails with wrong secret", async () => {
  const secret1 = generateSecret();
  const secret2 = generateSecret();
  const timestamp = Date.now();

  const header = await createAuthHeader(secret1, timestamp);
  const valid = await verifyAuthHeader(secret2, header);

  expect(valid).toBe(false);
});

test("verifyAuthHeader fails with tampered timestamp", async () => {
  const secret = generateSecret();
  const timestamp = Date.now();

  const header = await createAuthHeader(secret, timestamp);
  // Tamper with timestamp
  const parts = header.split(":");
  const tamperedHeader = `${Number.parseInt(parts[0] || "0", 10) + 1000}:${parts[1]}`;
  const valid = await verifyAuthHeader(secret, tamperedHeader);

  expect(valid).toBe(false);
});

test("verifyAuthHeader fails with tampered signature", async () => {
  const secret = generateSecret();
  const timestamp = Date.now();

  const header = await createAuthHeader(secret, timestamp);
  // Tamper with signature
  const parts = header.split(":");
  const tamperedHeader = `${parts[0]}:${parts[1]?.slice(0, -1)}X`;
  const valid = await verifyAuthHeader(secret, tamperedHeader);

  expect(valid).toBe(false);
});

test("verifyAuthHeader fails with expired timestamp", async () => {
  const secret = generateSecret();
  // Timestamp from 10 minutes ago
  const timestamp = Date.now() - 10 * 60 * 1000;

  const header = await createAuthHeader(secret, timestamp);
  // Default maxAge is 5 minutes, so this should fail
  const valid = await verifyAuthHeader(secret, header);

  expect(valid).toBe(false);
});

test("verifyAuthHeader succeeds with timestamp within maxAge", async () => {
  const secret = generateSecret();
  // Timestamp from 3 minutes ago
  const timestamp = Date.now() - 3 * 60 * 1000;

  const header = await createAuthHeader(secret, timestamp);
  // Default maxAge is 5 minutes, so this should succeed
  const valid = await verifyAuthHeader(secret, header);

  expect(valid).toBe(true);
});

test("verifyAuthHeader respects custom maxAge", async () => {
  const secret = generateSecret();
  // Timestamp from 2 minutes ago
  const timestamp = Date.now() - 2 * 60 * 1000;

  const header = await createAuthHeader(secret, timestamp);

  // Should fail with 1 minute maxAge
  const valid1 = await verifyAuthHeader(secret, header, 1 * 60 * 1000);
  expect(valid1).toBe(false);

  // Should succeed with 3 minute maxAge
  const valid2 = await verifyAuthHeader(secret, header, 3 * 60 * 1000);
  expect(valid2).toBe(true);
});

test("verifyAuthHeader rejects future timestamps beyond clock skew", async () => {
  const secret = generateSecret();
  // Timestamp from 2 minutes in the future
  const timestamp = Date.now() + 2 * 60 * 1000;

  const header = await createAuthHeader(secret, timestamp);
  const valid = await verifyAuthHeader(secret, header);

  expect(valid).toBe(false);
});

test("verifyAuthHeader allows small future timestamps (clock skew)", async () => {
  const secret = generateSecret();
  // Timestamp from 30 seconds in the future (within 1 minute tolerance)
  const timestamp = Date.now() + 30 * 1000;

  const header = await createAuthHeader(secret, timestamp);
  const valid = await verifyAuthHeader(secret, header);

  expect(valid).toBe(true);
});

test("verifyAuthHeader fails with malformed header (no colon)", async () => {
  const secret = generateSecret();
  const valid = await verifyAuthHeader(secret, "malformed-header");

  expect(valid).toBe(false);
});

test("verifyAuthHeader fails with malformed header (extra colons)", async () => {
  const secret = generateSecret();
  const timestamp = Date.now();

  const header = await createAuthHeader(secret, timestamp);
  const malformed = `${header}:extra`;
  const valid = await verifyAuthHeader(secret, malformed);

  expect(valid).toBe(false);
});

test("verifyAuthHeader fails with empty timestamp", async () => {
  const secret = generateSecret();
  const valid = await verifyAuthHeader(secret, ":signature");

  expect(valid).toBe(false);
});

test("verifyAuthHeader fails with empty signature", async () => {
  const secret = generateSecret();
  const timestamp = Date.now();
  const valid = await verifyAuthHeader(secret, `${timestamp}:`);

  expect(valid).toBe(false);
});

test("verifyAuthHeader fails with non-numeric timestamp", async () => {
  const secret = generateSecret();
  const signature = await signMessage(secret, "not-a-number");
  const valid = await verifyAuthHeader(secret, `not-a-number:${signature}`);

  expect(valid).toBe(false);
});