import express from 'express';
import * as roomCtrl from '../controllers/roomController.js';
import { authenticate } from '../middleware/auth.js';

const router = express.Router();

// Apply auth to all room routes
router.use(authenticate);

const NAME_MAX = 100;
const DEFAULT_LIMIT = 50;
const MAX_LIMIT = 200;

function isValidName(name) {
    if (name === undefined || name === null) {
        return true;
    }
    if (typeof name !== 'string') {
        return false;
    }
    return name.length <= NAME_MAX;
}

function isValidType(type) {
    if (type === undefined || type === null) {
        return true;
    }
    if (type !== 'group' && type !== 'direct') {
        return false;
    }
    return true;
}

function isValidMembers(members) {
    if (members === undefined || members === null) {
        return true;
    }
    if (!Array.isArray(members)) {
        return false;
    }
    for (let i = 0; i < members.length; i++) {
        if (typeof members[i] !== 'string') {
            return false;
        }
    }
    return true;
}

// Search rooms by name
router.get('/search', async function(req, res) {
    const q = req.query.q;
    if (typeof q !== 'string' || q.length < 1) {
        return res.status(400).json({ error: 'invalid_query' });
    }
    const results = await roomCtrl.searchRooms({ q: q });
    res.json(results);
});

// List rooms with pagination
router.get('/', async function(req, res) {
    let limit = parseInt(req.query.limit, 10);
    let offset = parseInt(req.query.offset, 10);

    if (isNaN(limit) || limit < 1) {
        limit = DEFAULT_LIMIT;
    }
    if (limit > MAX_LIMIT) {
        limit = MAX_LIMIT;
    }
    if (isNaN(offset) || offset < 0) {
        offset = 0;
    }

    const filters = {};
    if (req.query.type) {
        filters.type = req.query.type;
    }
    if (req.query.memberId) {
        filters.memberId = req.query.memberId;
    }

    const rooms = await roomCtrl.listRooms({ limit: limit, offset: offset, filters: filters });
    res.json(rooms);
});

// Get room by id
router.get('/:id', async function(req, res) {
    const room = await roomCtrl.getRoomById(req.params.id);
    if (!room) {
        return res.status(404).json({ error: 'not_found' });
    }
    res.json(room);
});

// Get room messages (chat history)
router.get('/:id/messages', async function(req, res) {
    let limit = parseInt(req.query.limit, 10);
    let offset = parseInt(req.query.offset, 10);

    if (isNaN(limit) || limit < 1) {
        limit = DEFAULT_LIMIT;
    }
    if (limit > MAX_LIMIT) {
        limit = MAX_LIMIT;
    }
    if (isNaN(offset) || offset < 0) {
        offset = 0;
    }

    const room = await roomCtrl.getRoomById(req.params.id);
    if (!room) {
        return res.status(404).json({ error: 'room_not_found' });
    }

    const messages = await roomCtrl.getRoomMessages(req.params.id, { limit: limit, offset: offset });
    res.json(messages);
});

// Create room
router.post('/', async function(req, res) {
    const name = req.body.name;
    const type = req.body.type;
    const members = req.body.members;

    if (!isValidName(name)) {
        return res.status(400).json({ error: 'invalid_name' });
    }
    if (!isValidType(type)) {
        return res.status(400).json({ error: 'invalid_type' });
    }
    if (!isValidMembers(members)) {
        return res.status(400).json({ error: 'invalid_members' });
    }

    const result = await roomCtrl.createRoom({ name: name, type: type, members: members });
    if (result.error === 'member_not_found') {
        return res.status(400).json({ error: 'member_not_found', memberId: result.memberId });
    }

    res.status(201).json(result);
});

// Update room
router.put('/:id', async function(req, res) {
    const name = req.body.name;
    const type = req.body.type;

    if (!isValidName(name)) {
        return res.status(400).json({ error: 'invalid_name' });
    }
    if (!isValidType(type)) {
        return res.status(400).json({ error: 'invalid_type' });
    }

    const updates = {};
    if (name !== undefined) {
        updates.name = name;
    }
    if (type !== undefined) {
        updates.type = type;
    }

    const room = await roomCtrl.updateRoom(req.params.id, updates);
    if (!room) {
        return res.status(404).json({ error: 'not_found' });
    }
    res.json(room);
});

// Add member to room
router.post('/:id/members', async function(req, res) {
    const userId = req.body.userId;

    if (typeof userId !== 'string' || userId.length < 1) {
        return res.status(400).json({ error: 'invalid_user_id' });
    }

    const room = await roomCtrl.addMember(req.params.id, userId);
    if (!room) {
        return res.status(404).json({ error: 'not_found' });
    }
    res.json(room);
});

// Remove member from room
router.delete('/:id/members/:userId', async function(req, res) {
    const room = await roomCtrl.removeMember(req.params.id, req.params.userId);
    if (!room) {
        return res.status(404).json({ error: 'not_found' });
    }
    res.json(room);
});

// Delete room
router.delete('/:id', async function(req, res) {
    const ok = await roomCtrl.deleteRoom(req.params.id);
    if (!ok) {
        return res.status(404).json({ error: 'not_found' });
    }
    res.status(204).send();
});

export default router;