import { expect, tap } from '@git.zone/tstest/tapbundle';
import * as smartmongo from '../ts/index.js';

const { SessionEngine } = smartmongo.tsmdb;

let sessionEngine: InstanceType<typeof SessionEngine>;

// ============================================================================
// Setup
// ============================================================================

tap.test('session: should create SessionEngine instance', async () => {
  sessionEngine = new SessionEngine({
    sessionTimeoutMs: 1000, // 1 second for testing
    cleanupIntervalMs: 10000, // 10 seconds to avoid cleanup during tests
  });
  expect(sessionEngine).toBeTruthy();
});

// ============================================================================
// Session Lifecycle Tests
// ============================================================================

tap.test('session: startSession should create session with auto-generated ID', async () => {
  const session = sessionEngine.startSession();

  expect(session).toBeTruthy();
  expect(session.id).toBeTruthy();
  expect(session.id.length).toBeGreaterThanOrEqual(32); // UUID hex string (32 or 36 with hyphens)
  expect(session.createdAt).toBeGreaterThan(0);
  expect(session.lastActivityAt).toBeGreaterThan(0);
  expect(session.inTransaction).toBeFalse();
});

tap.test('session: startSession should create session with specified ID', async () => {
  const customId = 'custom-session-id-12345';
  const session = sessionEngine.startSession(customId);

  expect(session.id).toEqual(customId);
});

tap.test('session: startSession should create session with metadata', async () => {
  const metadata = { client: 'test-client', version: '1.0' };
  const session = sessionEngine.startSession(undefined, metadata);

  expect(session.metadata).toBeTruthy();
  expect(session.metadata!.client).toEqual('test-client');
  expect(session.metadata!.version).toEqual('1.0');
});

tap.test('session: getSession should return session by ID', async () => {
  const created = sessionEngine.startSession('get-session-test');
  const retrieved = sessionEngine.getSession('get-session-test');

  expect(retrieved).toBeTruthy();
  expect(retrieved!.id).toEqual('get-session-test');
  expect(retrieved!.id).toEqual(created.id);
});

tap.test('session: getSession should return undefined for non-existent session', async () => {
  const session = sessionEngine.getSession('non-existent-session-id');
  expect(session).toBeUndefined();
});

tap.test('session: touchSession should update lastActivityAt', async () => {
  const session = sessionEngine.startSession('touch-test-session');
  const originalLastActivity = session.lastActivityAt;

  // Wait a bit to ensure time difference
  await new Promise(resolve => setTimeout(resolve, 10));

  const touched = sessionEngine.touchSession('touch-test-session');
  expect(touched).toBeTrue();

  const updated = sessionEngine.getSession('touch-test-session');
  expect(updated!.lastActivityAt).toBeGreaterThanOrEqual(originalLastActivity);
});

tap.test('session: touchSession should return false for non-existent session', async () => {
  const touched = sessionEngine.touchSession('non-existent-touch-session');
  expect(touched).toBeFalse();
});

tap.test('session: endSession should remove the session', async () => {
  sessionEngine.startSession('end-session-test');
  expect(sessionEngine.getSession('end-session-test')).toBeTruthy();

  const ended = await sessionEngine.endSession('end-session-test');
  expect(ended).toBeTrue();

  expect(sessionEngine.getSession('end-session-test')).toBeUndefined();
});

tap.test('session: endSession should return false for non-existent session', async () => {
  const ended = await sessionEngine.endSession('non-existent-end-session');
  expect(ended).toBeFalse();
});

// ============================================================================
// Session Expiry Tests
// ============================================================================

tap.test('session: isSessionExpired should return false for fresh session', async () => {
  const session = sessionEngine.startSession('fresh-session');
  const isExpired = sessionEngine.isSessionExpired(session);
  expect(isExpired).toBeFalse();
});

tap.test('session: isSessionExpired should return true for old session', async () => {
  // Create a session with old lastActivityAt
  const session = sessionEngine.startSession('old-session');
  // Manually set lastActivityAt to old value (sessionTimeoutMs is 1000ms)
  (session as any).lastActivityAt = Date.now() - 2000;

  const isExpired = sessionEngine.isSessionExpired(session);
  expect(isExpired).toBeTrue();
});

tap.test('session: getSession should return undefined for expired session', async () => {
  const session = sessionEngine.startSession('expiring-session');
  // Manually expire the session
  (session as any).lastActivityAt = Date.now() - 2000;

  const retrieved = sessionEngine.getSession('expiring-session');
  expect(retrieved).toBeUndefined();
});

// ============================================================================
// Transaction Integration Tests
// ============================================================================

tap.test('session: startTransaction should mark session as in transaction', async () => {
  sessionEngine.startSession('txn-session-1');
  const started = sessionEngine.startTransaction('txn-session-1', 'txn-id-1', 1);

  expect(started).toBeTrue();

  const session = sessionEngine.getSession('txn-session-1');
  expect(session!.inTransaction).toBeTrue();
  expect(session!.txnId).toEqual('txn-id-1');
  expect(session!.txnNumber).toEqual(1);
});

tap.test('session: startTransaction should return false for non-existent session', async () => {
  const started = sessionEngine.startTransaction('non-existent-txn-session', 'txn-id');
  expect(started).toBeFalse();
});

tap.test('session: endTransaction should clear transaction state', async () => {
  sessionEngine.startSession('txn-session-2');
  sessionEngine.startTransaction('txn-session-2', 'txn-id-2');

  const ended = sessionEngine.endTransaction('txn-session-2');
  expect(ended).toBeTrue();

  const session = sessionEngine.getSession('txn-session-2');
  expect(session!.inTransaction).toBeFalse();
  expect(session!.txnId).toBeUndefined();
  expect(session!.txnNumber).toBeUndefined();
});

tap.test('session: endTransaction should return false for non-existent session', async () => {
  const ended = sessionEngine.endTransaction('non-existent-end-txn-session');
  expect(ended).toBeFalse();
});

tap.test('session: getTransactionId should return transaction ID', async () => {
  sessionEngine.startSession('txn-id-session');
  sessionEngine.startTransaction('txn-id-session', 'my-txn-id');

  const txnId = sessionEngine.getTransactionId('txn-id-session');
  expect(txnId).toEqual('my-txn-id');
});

tap.test('session: getTransactionId should return undefined for session without transaction', async () => {
  sessionEngine.startSession('no-txn-session');
  const txnId = sessionEngine.getTransactionId('no-txn-session');
  expect(txnId).toBeUndefined();
});

tap.test('session: getTransactionId should return undefined for non-existent session', async () => {
  const txnId = sessionEngine.getTransactionId('non-existent-txn-id-session');
  expect(txnId).toBeUndefined();
});

tap.test('session: isInTransaction should return correct state', async () => {
  sessionEngine.startSession('in-txn-check-session');

  expect(sessionEngine.isInTransaction('in-txn-check-session')).toBeFalse();

  sessionEngine.startTransaction('in-txn-check-session', 'txn-check');
  expect(sessionEngine.isInTransaction('in-txn-check-session')).toBeTrue();

  sessionEngine.endTransaction('in-txn-check-session');
  expect(sessionEngine.isInTransaction('in-txn-check-session')).toBeFalse();
});

tap.test('session: isInTransaction should return false for non-existent session', async () => {
  expect(sessionEngine.isInTransaction('non-existent-in-txn-session')).toBeFalse();
});

// ============================================================================
// Session Listing Tests
// ============================================================================

tap.test('session: listSessions should return all active sessions', async () => {
  // Close and recreate to have a clean slate
  sessionEngine.close();
  sessionEngine = new SessionEngine({
    sessionTimeoutMs: 10000,
    cleanupIntervalMs: 60000,
  });

  sessionEngine.startSession('list-session-1');
  sessionEngine.startSession('list-session-2');
  sessionEngine.startSession('list-session-3');

  const sessions = sessionEngine.listSessions();
  expect(sessions.length).toEqual(3);
});

tap.test('session: listSessions should not include expired sessions', async () => {
  const session = sessionEngine.startSession('expired-list-session');
  // Expire the session
  (session as any).lastActivityAt = Date.now() - 20000;

  const sessions = sessionEngine.listSessions();
  const found = sessions.find(s => s.id === 'expired-list-session');
  expect(found).toBeUndefined();
});

tap.test('session: getSessionCount should return correct count', async () => {
  const count = sessionEngine.getSessionCount();
  expect(count).toBeGreaterThanOrEqual(3); // We created 3 sessions above
});

tap.test('session: getSessionsWithTransactions should filter correctly', async () => {
  // Clean slate
  sessionEngine.close();
  sessionEngine = new SessionEngine({
    sessionTimeoutMs: 10000,
    cleanupIntervalMs: 60000,
  });

  sessionEngine.startSession('no-txn-1');
  sessionEngine.startSession('no-txn-2');
  sessionEngine.startSession('with-txn-1');
  sessionEngine.startSession('with-txn-2');

  sessionEngine.startTransaction('with-txn-1', 'txn-a');
  sessionEngine.startTransaction('with-txn-2', 'txn-b');

  const txnSessions = sessionEngine.getSessionsWithTransactions();
  expect(txnSessions.length).toEqual(2);
  expect(txnSessions.every(s => s.inTransaction)).toBeTrue();
});

// ============================================================================
// getOrCreateSession Tests
// ============================================================================

tap.test('session: getOrCreateSession should create if missing', async () => {
  const session = sessionEngine.getOrCreateSession('get-or-create-new');
  expect(session).toBeTruthy();
  expect(session.id).toEqual('get-or-create-new');
});

tap.test('session: getOrCreateSession should return existing session', async () => {
  const created = sessionEngine.startSession('get-or-create-existing');
  const retrieved = sessionEngine.getOrCreateSession('get-or-create-existing');

  expect(retrieved.id).toEqual(created.id);
  expect(retrieved.createdAt).toEqual(created.createdAt);
});

tap.test('session: getOrCreateSession should touch existing session', async () => {
  const session = sessionEngine.startSession('get-or-create-touch');
  const originalLastActivity = session.lastActivityAt;

  await new Promise(resolve => setTimeout(resolve, 10));

  sessionEngine.getOrCreateSession('get-or-create-touch');
  const updated = sessionEngine.getSession('get-or-create-touch');

  expect(updated!.lastActivityAt).toBeGreaterThanOrEqual(originalLastActivity);
});

// ============================================================================
// extractSessionId Static Method Tests
// ============================================================================

tap.test('session: extractSessionId should handle UUID object', async () => {
  const { ObjectId } = smartmongo.tsmdb;
  const uuid = new smartmongo.tsmdb.plugins.bson.UUID();
  const lsid = { id: uuid };

  const extracted = SessionEngine.extractSessionId(lsid);
  expect(extracted).toEqual(uuid.toHexString());
});

tap.test('session: extractSessionId should handle string ID', async () => {
  const lsid = { id: 'string-session-id' };

  const extracted = SessionEngine.extractSessionId(lsid);
  expect(extracted).toEqual('string-session-id');
});

tap.test('session: extractSessionId should handle binary format', async () => {
  const binaryData = Buffer.from('test-binary-uuid', 'utf8').toString('base64');
  const lsid = { id: { $binary: { base64: binaryData } } };

  const extracted = SessionEngine.extractSessionId(lsid);
  expect(extracted).toBeTruthy();
  expect(typeof extracted).toEqual('string');
});

tap.test('session: extractSessionId should return undefined for null/undefined', async () => {
  expect(SessionEngine.extractSessionId(null)).toBeUndefined();
  expect(SessionEngine.extractSessionId(undefined)).toBeUndefined();
});

tap.test('session: extractSessionId should return undefined for empty object', async () => {
  expect(SessionEngine.extractSessionId({})).toBeUndefined();
});

// ============================================================================
// refreshSession Tests
// ============================================================================

tap.test('session: refreshSession should update lastActivityAt', async () => {
  const session = sessionEngine.startSession('refresh-session-test');
  const originalLastActivity = session.lastActivityAt;

  await new Promise(resolve => setTimeout(resolve, 10));

  const refreshed = sessionEngine.refreshSession('refresh-session-test');
  expect(refreshed).toBeTrue();

  const updated = sessionEngine.getSession('refresh-session-test');
  expect(updated!.lastActivityAt).toBeGreaterThanOrEqual(originalLastActivity);
});

tap.test('session: refreshSession should return false for non-existent session', async () => {
  const refreshed = sessionEngine.refreshSession('non-existent-refresh-session');
  expect(refreshed).toBeFalse();
});

// ============================================================================
// Cleanup
// ============================================================================

tap.test('session: close should clear all sessions', async () => {
  sessionEngine.startSession('close-test-session');
  expect(sessionEngine.getSessionCount()).toBeGreaterThan(0);

  sessionEngine.close();

  expect(sessionEngine.getSessionCount()).toEqual(0);
});

export default tap.start();