import { Router, type Request, type Response } from 'express';
import type { StorageServiceInterface } from '../services/storageInterface.js';
import type { RelayService } from '../services/relay.js';
import type { MsgChiffre, StoredMessage } from '../types/message.js';
import { validateMsgChiffre } from '../lib/validate.js';
import { logger } from '../lib/logger.js';

function handleGetMessages(
  storage: StorageServiceInterface,
  req: Request,
  res: Response,
): void {
  try {
    const start = parseInt(req.query.start as string, 10);
    const end = parseInt(req.query.end as string, 10);
    const service = req.query.service as string | undefined;

    if (isNaN(start) || isNaN(end)) {
      res.status(400).json({ error: 'start and end timestamps required' });
      return;
    }

    const messages = storage.getMessages(start, end, service);
    const msgChiffres: MsgChiffre[] = messages.map((m) => m.msg);
    res.json(msgChiffres);
  } catch (error) {
    logger.error({ err: error }, 'Error getting messages');
    res.status(500).json({ error: 'Internal server error' });
  }
}

function handlePostMessage(
  storage: StorageServiceInterface,
  relay: RelayService,
  req: Request,
  res: Response,
): void {
  void (async (): Promise<void> => {
    try {
      if (!validateMsgChiffre(req.body)) {
        res.status(400).json({ error: 'Invalid message format' });
        return;
      }
      const msg = req.body as MsgChiffre;

      const alreadySeen = storage.hasSeenHash(msg.hash);
      const stored: StoredMessage = {
        msg,
        received_at: Date.now(),
        relayed: false,
      };

      storage.storeMessage(stored);

      if (!alreadySeen) {
        await relay.relayMessage(msg);
        stored.relayed = true;
      }

      res.status(201).json({ hash: msg.hash, stored: true });
    } catch (error) {
      logger.error({ err: error }, 'Error storing message');
      res.status(500).json({ error: 'Internal server error' });
    }
  })();
}

function handleGetMessageByHash(
  storage: StorageServiceInterface,
  req: Request,
  res: Response,
): void {
  try {
    const hash = req.params.hash as string;
    if (hash.length === 0) {
      res.status(400).json({ error: 'Hash parameter required' });
      return;
    }
    const stored = storage.getMessage(hash);
    if (stored === undefined) {
      res.status(404).json({ error: 'Message not found' });
      return;
    }
    res.json(stored.msg);
  } catch (error) {
    logger.error({ err: error }, 'Error getting message by hash');
    res.status(500).json({ error: 'Internal server error' });
  }
}

export function createMessagesRouter(
  storage: StorageServiceInterface,
  relay: RelayService,
): Router {
  const router = Router();

  router.get('/', (req, res) => handleGetMessages(storage, req, res));
  router.post('/', (req, res) => handlePostMessage(storage, relay, req, res));
  router.get('/:hash', (req, res) => handleGetMessageByHash(storage, req, res));

  return router;
}