import { ImapFlow } from 'imapflow';
import { getServerSession } from 'next-auth';
import { authOptions } from '@/app/api/auth/[...nextauth]/route';

let client: ImapFlow | null = null;

export async function getImapClient() {
  if (client) return client;

  const session = await getServerSession(authOptions);
  if (!session?.user?.email) {
    throw new Error('No authenticated user');
  }

  client = new ImapFlow({
    host: process.env.IMAP_HOST || 'imap.gmail.com',
    port: parseInt(process.env.IMAP_PORT || '993', 10),
    secure: true,
    auth: {
      user: session.user.email,
      pass: session.user.accessToken
    },
    logger: false
  });

  await client.connect();
  return client;
}

export async function moveEmails(emailIds: number[], targetFolder: string) {
  const imap = await getImapClient();
  const lock = await imap.getMailboxLock('INBOX');
  try {
    for (const id of emailIds) {
      const message = await imap.fetchOne(id.toString(), { uid: true });
      if (message) {
        await imap.messageMove(message.uid, targetFolder);
      }
    }
  } finally {
    lock.release();
  }
}

export async function markAsRead(emailIds: number[], isRead: boolean) {
  const imap = await getImapClient();
  const lock = await imap.getMailboxLock('INBOX');
  try {
    for (const id of emailIds) {
      const message = await imap.fetchOne(id.toString(), { uid: true });
      if (message) {
        await imap.messageFlagsAdd(message.uid, isRead ? ['\\Seen'] : [], { uid: true });
      }
    }
  } finally {
    lock.release();
  }
}