var process = require('process')
var fs = require('fs')
var path = require('path')
// Handle SIGINT
process.on('SIGINT', () => {
  console.info("SIGINT Received, exiting...")
  process.exit(0)
})

// Handle SIGTERM
process.on('SIGTERM', () => {
  console.info("SIGTERM Received, exiting...")
  process.exit(0)
})

const parser = require('ua-parser-js');
const { uniqueNamesGenerator, animals, colors } = require('unique-names-generator');

class SnapdropServer {

    constructor(port) {
        const WebSocket = require('ws');
        this._wss = new WebSocket.Server({ port: port });
        this._wss.on('connection', (socket, request) => this._onConnection(new Peer(socket, request)));
        this._wss.on('headers', (headers, response) => this._onHeaders(headers, response));

        this._rooms = {};
        this._userIdIndex = {};
        this._fingerprintIndex = {};
        this._pairingRecords = {};
        this._pendingPairRequests = {};
        this._canvasRooms = {};
        this._pairingCodes = {};
        this._radarPool = {};
        this._activeScreenShares = {};

        this._pairingCodeCleanup = setInterval(() => {
            const now = Date.now();
            for (const code in this._pairingCodes) {
                if (now > this._pairingCodes[code].expiresAt) {
                    delete this._pairingCodes[code];
                }
            }
        }, 60000);

        this._radarPoolCleanup = setInterval(() => {
            const now = Date.now();
            for (const deviceId in this._radarPool) {
                if (now - this._radarPool[deviceId].lastBroadcast > 30000) {
                    delete this._radarPool[deviceId];
                }
            }
        }, 10000);

        this._loadPairingRecords();

        if (this._wss._server) {
            this._wss._server.on('request', (req, res) => {
                if (req.url === '/health') {
                    const totalPeers = Object.values(this._rooms).reduce((sum, room) => sum + Object.keys(room).length, 0);
                    res.writeHead(200, { 'Content-Type': 'application/json' });
                    res.end(JSON.stringify({
                        status: 'healthy',
                        peers: totalPeers,
                        pairingCodes: Object.keys(this._pairingCodes).length,
                        radarDevices: Object.keys(this._radarPool).length,
                        activeScreenShares: Object.keys(this._activeScreenShares).length,
                        canvasRooms: Object.keys(this._canvasRooms).length,
                        uptime: process.uptime()
                    }));
                }
            });
        }

        console.log('Snapdrop is running on port', port);
    }

    _loadPairingRecords() {
        const dataFile = path.join(__dirname, 'data', 'pairing_records.json');
        try {
            if (fs.existsSync(dataFile)) {
                this._pairingRecords = JSON.parse(fs.readFileSync(dataFile, 'utf8'));
            }
        } catch (e) {
            console.error('Failed to load pairing records:', e.message);
        }
    }

    _savePairingRecords() {
        const dataDir = path.join(__dirname, 'data');
        if (!fs.existsSync(dataDir)) fs.mkdirSync(dataDir, { recursive: true });
        const dataFile = path.join(dataDir, 'pairing_records.json');
        try {
            fs.writeFileSync(dataFile, JSON.stringify(this._pairingRecords, null, 2));
        } catch (e) {
            console.error('Failed to save pairing records:', e.message);
        }
    }

    _onConnection(peer) {
        this._joinRoom(peer);
        peer.socket.on('message', message => this._onMessage(peer, message));
        peer.socket.on('error', console.error);
        this._keepAlive(peer);

        this._send(peer, {
            type: 'registered',
            id: peer.id,
            fingerprint: peer.fingerprint || '',
            userId: peer.userId || ''
        });

        this._send(peer, {
            type: 'display-name',
            message: {
                displayName: peer.name.displayName,
                deviceName: peer.name.deviceName
            }
        });
    }

    _onHeaders(headers, response) {
        if (response.headers.cookie && response.headers.cookie.indexOf('peerid=') > -1) return;
        response.peerId = Peer.uuid();
        headers.push('Set-Cookie: peerid=' + response.peerId + "; SameSite=Strict; Secure");
    }

    _onMessage(sender, message) {
        try {
            message = JSON.parse(message);
        } catch (e) {
            return;
        }

        switch (message.type) {
            case 'disconnect':
                this._leaveRoom(sender);
                break;
            case 'pong':
                sender.lastBeat = Date.now();
                break;
            case 'register':
                this._handleRegister(sender, message);
                break;
            case 'discoverMyDevices':
                this._handleDiscoverMyDevices(sender, message);
                break;
            case 'transportNegotiate':
                this._handleTransportNegotiate(sender, message);
                break;
            case 'wsRelay':
                this._handleWsRelay(sender, message);
                break;
            case 'pair-request':
            case 'pairRequest':
                this._handlePairRequest(sender, message);
                break;
            case 'pair-accept':
            case 'pairAccept':
                this._handlePairAccept(sender, message);
                break;
            case 'pair-reject':
            case 'pairReject':
                this._handlePairReject(sender, message);
                break;
            case 'heartbeat':
                sender.lastBeat = Date.now();
                this._send(sender, {
                    type: 'heartbeat_ack',
                    timestamp: Date.now()
                });
                break;
            case 'discover':
                this._handleDiscover(sender, message);
                break;
            case 'ping':
                sender.lastBeat = Date.now();
                this._send(sender, { type: 'pong', timestamp: Date.now() });
                break;
            case 'textMessage':
                this._handleTextMessage(sender, message);
                break;
            case 'fileMeta':
                this._handleFileMeta(sender, message);
                break;
            case 'canvas-stroke':
                this._handleCanvasStroke(sender, message);
                break;
            case 'canvas-cursor':
                this._handleCanvasCursor(sender, message);
                break;
            case 'canvas-join':
                this._handleCanvasJoin(sender, message);
                break;
            case 'canvas-leave':
                this._handleCanvasLeave(sender, message);
                break;
            case 'canvas-snapshot':
                this._handleCanvasSnapshot(sender, message);
                break;
            case 'pairing-code-create':
                this._handlePairingCodeCreate(sender, message);
                break;
            case 'pairing-code-join':
                this._handlePairingCodeJoin(sender, message);
                break;
            case 'radar-broadcast':
                this._handleRadarBroadcast(sender, message);
                break;
            case 'radar-scan':
                this._handleRadarScan(sender, message);
                break;
            case 'screen-share-request':
                this._handleScreenShareRequest(sender, message);
                break;
            case 'screen-share-accept':
                this._handleScreenShareAccept(sender, message);
                break;
            case 'screen-share-reject':
                this._handleScreenShareReject(sender, message);
                break;
            case 'screen-share-stop':
                this._handleScreenShareStop(sender, message);
                break;
        }

        const handledTypes = ['disconnect', 'pong', 'register', 'discoverMyDevices', 'discover', 'transportNegotiate', 'wsRelay', 'pair-request', 'pairRequest', 'pair-accept', 'pairAccept', 'pair-reject', 'pairReject', 'heartbeat', 'ping', 'textMessage', 'fileMeta', 'canvas-stroke', 'canvas-cursor', 'canvas-join', 'canvas-leave', 'canvas-snapshot', 'pairing-code-create', 'pairing-code-join', 'radar-broadcast', 'radar-scan', 'screen-share-request', 'screen-share-accept', 'screen-share-reject', 'screen-share-stop'];
        if (message.to && !handledTypes.includes(message.type)) {
            let recipientId = message.to;
            let recipient = this._resolveTarget(sender, recipientId);

            if (recipient) {
                delete message.to;
                message.sender = sender.id;
                message.from = sender.fingerprint || sender.id;
                message.fromPeerId = sender.id;
                this._send(recipient, message);
            } else {
                console.log('Message routing failed: target not found for', recipientId, 'from', sender.id);
            }
            return;
        }
    }

    _handleRegister(sender, message) {
        const data = message.payload || message.data || {};
        if (data.userId) {
            const oldUserId = sender.userId;
            sender.userId = data.userId;
            if (oldUserId && this._userIdIndex[oldUserId]) {
                this._userIdIndex[oldUserId].delete(sender.id);
                if (this._userIdIndex[oldUserId].size === 0) {
                    delete this._userIdIndex[oldUserId];
                }
            }
            if (!this._userIdIndex[sender.userId]) {
                this._userIdIndex[sender.userId] = new Set();
            }
            this._userIdIndex[sender.userId].add(sender.id);
        }
        if (data.fingerprint) {
            const oldFingerprint = sender.fingerprint;
            sender.fingerprint = data.fingerprint;
            if (oldFingerprint && this._fingerprintIndex[oldFingerprint] === sender.id) {
                delete this._fingerprintIndex[oldFingerprint];
            }
            const existingPeerId = this._fingerprintIndex[sender.fingerprint];
            if (existingPeerId && existingPeerId !== sender.id) {
                const existingPeer = this._findPeer(existingPeerId);
                if (existingPeer) {
                    console.log('Replacing old connection for fingerprint:', sender.fingerprint, 'old peer:', existingPeerId, 'new peer:', sender.id);
                    this._leaveRoom(existingPeer);
                }
            }
            this._fingerprintIndex[sender.fingerprint] = sender.id;
            console.log('Register fingerprint mapping:', sender.fingerprint, '->', sender.id);
        }
        if (data.ipCity) sender.ipCity = data.ipCity;
        if (data.ipRange) sender.ipRange = data.ipRange;
        if (data.deviceModel) sender.deviceModel = data.deviceModel;
        if (data.platform) sender.platform = data.platform;
        if (data.alias) sender.name.displayName = data.alias;
        if (data.deviceType) sender.name.type = data.deviceType;

        this._send(sender, {
            type: 'registered',
            id: sender.id,
            fingerprint: sender.fingerprint || '',
            userId: sender.userId
        });
    }

    _handleDiscover(sender, message) {
        const allPeers = [];
        for (const roomId in this._rooms) {
            for (const peerId in this._rooms[roomId]) {
                const peer = this._rooms[roomId][peerId];
                if (peer.id !== sender.id) {
                    allPeers.push(peer.getInfo());
                }
            }
        }
        this._send(sender, {
            type: 'discover_response',
            devices: allPeers
        });
    }

    _handleDiscoverMyDevices(sender, message) {
        const payload = message.payload || message.data || {};
        const userId = payload.userId || message.userId || sender.userId;
        if (!userId) {
            this._send(sender, {
                type: 'myDevicesResponse',
                devices: [],
                error: 'userId required'
            });
            return;
        }

        const seenFingerprints = new Map();
        for (const roomId in this._rooms) {
            for (const peerId in this._rooms[roomId]) {
                const peer = this._rooms[roomId][peerId];
                if (peer.id === sender.id) continue;
                if (peer.userId === userId) {
                    const fp = peer.fingerprint || peer.id;
                    if (!seenFingerprints.has(fp)) {
                        seenFingerprints.set(fp, {
                            id: peer.id,
                            fingerprint: peer.fingerprint || '',
                            alias: peer.name.displayName,
                            deviceName: peer.name.deviceName,
                            deviceModel: peer.deviceModel || '',
                            platform: peer.platform || '',
                            ip: peer.ip,
                            ipCity: peer.ipCity || '',
                            isOnline: true,
                            rtcSupported: peer.rtcSupported
                        });
                    }
                }
            }
        }

        this._send(sender, {
            type: 'myDevicesResponse',
            devices: Array.from(seenFingerprints.values())
        });
    }

    _handleTransportNegotiate(sender, message) {
        const targetId = message.to;
        if (!targetId) return;

        let targetPeer = this._findPeer(targetId);

        if (!targetPeer && this._fingerprintIndex[targetId]) {
            targetPeer = this._findPeer(this._fingerprintIndex[targetId]);
        }

        if (!targetPeer) {
            this._send(sender, {
                type: 'transportNegotiateResponse',
                success: false,
                error: 'Target device not found'
            });
            return;
        }

        this._send(targetPeer, {
            type: 'transportNegotiate',
            from: sender.fingerprint || sender.id,
            transport: message.transport,
            payload: message.payload || {}
        });
    }

    _handlePairRequest(sender, message) {
        const targetId = message.to;
        if (!targetId) return;

        let targetPeer = this._findPeer(targetId);

        if (!targetPeer && this._fingerprintIndex[targetId]) {
            targetPeer = this._findPeer(this._fingerprintIndex[targetId]);
        }

        if (!targetPeer) {
            this._send(sender, {
                type: 'pair-response',
                from: sender.id,
                success: false,
                error: 'Target device not found'
            });
            return;
        }

        const requestId = Date.now().toString(36) + Math.random().toString(36).substr(2);
        this._pendingPairRequests[requestId] = {
            id: requestId,
            fromId: sender.id,
            toId: targetId,
            fingerprint: message.fingerprint || message.payload?.fingerprint || '',
            createdAt: Date.now(),
            expiresAt: Date.now() + 300000
        };

        this._send(targetPeer, {
            type: 'pair-request',
            from: sender.fingerprint || sender.id,
            requestId: requestId,
            fingerprint: this._pendingPairRequests[requestId].fingerprint,
            payload: message.payload || {}
        });
    }

    _handlePairAccept(sender, message) {
        const requestId = message.requestId || message.payload?.requestId;
        if (!requestId || !this._pendingPairRequests[requestId]) {
            this._send(sender, {
                type: 'pair-response',
                success: false,
                error: 'Request not found or expired'
            });
            return;
        }

        const req = this._pendingPairRequests[requestId];
        delete this._pendingPairRequests[requestId];

        const pairKey1 = req.fromId + ':' + sender.id;
        const pairKey2 = sender.id + ':' + req.fromId;
        this._pairingRecords[pairKey1] = {
            deviceId: req.fromId,
            peerDeviceId: sender.id,
            peerFingerprint: req.fingerprint,
            pairedAt: Date.now(),
            isTrusted: true
        };
        this._pairingRecords[pairKey2] = {
            deviceId: sender.id,
            peerDeviceId: req.fromId,
            peerFingerprint: req.fingerprint,
            pairedAt: Date.now(),
            isTrusted: true
        };
        this._savePairingRecords();

        const fromPeer = this._findPeer(req.fromId);
        if (fromPeer) {
            this._send(fromPeer, {
                type: 'pair-response',
                from: sender.fingerprint || sender.id,
                success: true,
                requestId: requestId
            });
        }

        this._send(sender, {
            type: 'pair-response',
            from: fromPeer ? (fromPeer.fingerprint || fromPeer.id) : req.fromId,
            success: true,
            requestId: requestId
        });
    }

    _handlePairReject(sender, message) {
        const requestId = message.requestId || message.payload?.requestId;
        if (!requestId || !this._pendingPairRequests[requestId]) return;

        const req = this._pendingPairRequests[requestId];
        delete this._pendingPairRequests[requestId];

        const fromPeer = this._findPeer(req.fromId);
        if (fromPeer) {
            this._send(fromPeer, {
                type: 'pair-response',
                from: sender.fingerprint || sender.id,
                success: false,
                requestId: requestId,
                error: 'Rejected'
            });
        }
    }

    _findPeer(peerId) {
        for (const roomId in this._rooms) {
            if (this._rooms[roomId][peerId]) {
                return this._rooms[roomId][peerId];
            }
        }
        return null;
    }

    _resolveTarget(sender, targetId) {
        if (this._rooms[sender.ip] && this._rooms[sender.ip][targetId]) {
            return this._rooms[sender.ip][targetId];
        }

        let recipient = this._findPeer(targetId);
        if (recipient) return recipient;

        if (this._fingerprintIndex[targetId]) {
            const mappedPeerId = this._fingerprintIndex[targetId];
            console.log('Fingerprint mapping:', targetId, '->', mappedPeerId);
            recipient = this._findPeer(mappedPeerId);
            if (recipient) return recipient;
        }

        if (sender.userId) {
            const sameUserPeerIds = this._userIdIndex[sender.userId];
            if (sameUserPeerIds) {
                for (const peerId of sameUserPeerIds) {
                    if (peerId !== sender.id) {
                        recipient = this._findPeer(peerId);
                        if (recipient) return recipient;
                    }
                }
            }
        }

        if (this._userIdIndex[targetId]) {
            for (const peerId of this._userIdIndex[targetId]) {
                recipient = this._findPeer(peerId);
                if (recipient) return recipient;
            }
        }

        return null;
    }

    _handleTextMessage(sender, message) {
        const targetId = message.to;
        if (!targetId) return;

        const recipient = this._resolveTarget(sender, targetId);
        if (recipient) {
            this._send(recipient, {
                type: 'textMessage',
                from: sender.fingerprint || sender.id,
                fromPeerId: sender.id,
                to: recipient.id,
                message: message.message || message.payload || {},
                timestamp: message.timestamp || Date.now()
            });
        } else {
            console.log('textMessage routing failed: target not found for', targetId, 'from', sender.id);
        }
    }

    _handleFileMeta(sender, message) {
        const targetId = message.to;
        if (!targetId) return;

        const recipient = this._resolveTarget(sender, targetId);
        if (recipient) {
            this._send(recipient, {
                type: 'fileMeta',
                from: sender.fingerprint || sender.id,
                fromPeerId: sender.id,
                to: recipient.id,
                file: message.file || message.payload || {},
                timestamp: message.timestamp || Date.now()
            });
        } else {
            console.log('fileMeta routing failed: target not found for', targetId, 'from', sender.id);
        }
    }

    _handleWsRelay(sender, message) {
        const targetId = message.to;
        if (!targetId) return;

        let targetPeer = null;
        for (const roomId in this._rooms) {
            if (this._rooms[roomId][targetId]) {
                targetPeer = this._rooms[roomId][targetId];
                break;
            }
        }

        if (!targetPeer && this._fingerprintIndex[targetId]) {
            const mappedPeerId = this._fingerprintIndex[targetId];
            for (const roomId in this._rooms) {
                if (this._rooms[roomId][mappedPeerId]) {
                    targetPeer = this._rooms[roomId][mappedPeerId];
                    break;
                }
            }
        }

        if (!targetPeer && sender.userId) {
            const sameUserPeerIds = this._userIdIndex[sender.userId];
            if (sameUserPeerIds) {
                for (const peerId of sameUserPeerIds) {
                    if (peerId !== sender.id) {
                        for (const roomId in this._rooms) {
                            if (this._rooms[roomId][peerId]) {
                                targetPeer = this._rooms[roomId][peerId];
                                break;
                            }
                        }
                        if (targetPeer) break;
                    }
                }
            }
        }

        if (!targetPeer) {
            this._send(sender, {
                type: 'wsRelay',
                from: sender.fingerprint || sender.id,
                payload: {
                    relayType: 'error',
                    data: { error: 'Target peer not found', targetId: targetId }
                }
            });
            return;
        }

        const relayType = message.relayType || (message.payload && message.payload.relayType) || 'data';
        const payload = message.payload || {};
        if (!payload.relayType) {
            payload.relayType = relayType;
        }

        this._send(targetPeer, {
            type: 'wsRelay',
            from: sender.fingerprint || sender.id,
            payload: payload
        });
    }

    _handleCanvasJoin(sender, message) {
        const payload = message.payload || {};
        const canvasId = payload.canvasId;
        if (!canvasId) return;

        if (!this._canvasRooms[canvasId]) {
            this._canvasRooms[canvasId] = new Set();
        }
        this._canvasRooms[canvasId].add(sender.id);
        sender.canvasRoomId = canvasId;

        const members = Array.from(this._canvasRooms[canvasId]);
        for (const peerId of this._canvasRooms[canvasId]) {
            if (peerId === sender.id) continue;
            const peer = this._findPeer(peerId);
            if (peer) {
                this._send(peer, {
                    type: 'canvas-join',
                    from: sender.fingerprint || sender.id,
                    payload: { canvasId: canvasId, members: members }
                });
            }
        }

        this._send(sender, {
            type: 'canvas-join',
            from: 'server',
            payload: { canvasId: canvasId, members: members }
        });
        console.log('Canvas join:', sender.id, 'joined canvas', canvasId, 'members:', members.length);
    }

    _handleCanvasLeave(sender, message) {
        const payload = message.payload || {};
        const canvasId = payload.canvasId || sender.canvasRoomId;
        if (!canvasId || !this._canvasRooms[canvasId]) return;

        this._canvasRooms[canvasId].delete(sender.id);
        sender.canvasRoomId = null;

        for (const peerId of this._canvasRooms[canvasId]) {
            const peer = this._findPeer(peerId);
            if (peer) {
                this._send(peer, {
                    type: 'canvas-leave',
                    from: sender.fingerprint || sender.id,
                    payload: { canvasId: canvasId }
                });
            }
        }

        if (this._canvasRooms[canvasId].size === 0) {
            delete this._canvasRooms[canvasId];
        }
        console.log('Canvas leave:', sender.id, 'left canvas', canvasId);
    }

    _handleCanvasStroke(sender, message) {
        const payload = message.payload || {};
        const canvasId = payload.canvasId || sender.canvasRoomId;
        if (!canvasId || !this._canvasRooms[canvasId]) return;

        for (const peerId of this._canvasRooms[canvasId]) {
            if (peerId === sender.id) continue;
            const peer = this._findPeer(peerId);
            if (peer) {
                this._send(peer, {
                    type: 'canvas-stroke',
                    from: sender.fingerprint || sender.id,
                    payload: payload
                });
            }
        }
    }

    _handleCanvasCursor(sender, message) {
        const payload = message.payload || {};
        const canvasId = payload.canvasId || sender.canvasRoomId;
        if (!canvasId || !this._canvasRooms[canvasId]) return;

        for (const peerId of this._canvasRooms[canvasId]) {
            if (peerId === sender.id) continue;
            const peer = this._findPeer(peerId);
            if (peer) {
                this._send(peer, {
                    type: 'canvas-cursor',
                    from: sender.fingerprint || sender.id,
                    payload: payload
                });
            }
        }
    }

    _handleCanvasSnapshot(sender, message) {
        const payload = message.payload || {};
        const canvasId = payload.canvasId || sender.canvasRoomId;
        const action = payload.action || 'request';
        if (!canvasId || !this._canvasRooms[canvasId]) return;

        if (action === 'request') {
            const members = Array.from(this._canvasRooms[canvasId]);
            const otherMember = members.find(id => id !== sender.id);
            if (otherMember) {
                const peer = this._findPeer(otherMember);
                if (peer) {
                    this._send(peer, {
                        type: 'canvas-snapshot',
                        from: sender.fingerprint || sender.id,
                        payload: { canvasId: canvasId, action: 'request' }
                    });
                }
            }
        } else if (action === 'response') {
            const targetId = message.to;
            if (targetId) {
                const targetPeer = this._findPeer(targetId);
                if (targetPeer) {
                    this._send(targetPeer, {
                        type: 'canvas-snapshot',
                        from: sender.fingerprint || sender.id,
                        payload: payload
                    });
                }
            }
        }
    }

    _handlePairingCodeCreate(sender, message) {
        const payload = message.payload || message.data || {};
        let code = '';
        for (let i = 0; i < 4; i++) {
            code += Math.floor(Math.random() * 10).toString();
        }
        for (const existingCode in this._pairingCodes) {
            if (this._pairingCodes[existingCode].creatorId === sender.id) {
                delete this._pairingCodes[existingCode];
            }
        }
        this._pairingCodes[code] = {
            creatorId: sender.id,
            creatorFingerprint: sender.fingerprint || '',
            creatorAlias: payload.alias || sender.name.displayName,
            creatorDeviceModel: payload.deviceModel || sender.deviceModel || '',
            creatorDeviceType: payload.deviceType || sender.name.type || '',
            createdAt: Date.now(),
            expiresAt: Date.now() + 300000,
            used: false
        };
        this._send(sender, {
            type: 'pairing-code-created',
            pairingCode: code,
            expiresAt: this._pairingCodes[code].expiresAt
        });
        console.log('Pairing code created:', code, 'by', sender.id, '(' + (sender.fingerprint || '') + ')');
    }

    _handlePairingCodeJoin(sender, message) {
        const payload = message.payload || message.data || {};
        const code = (payload.pairingCode || '').trim();
        if (!code || !/^\d{4}$/.test(code)) {
            this._send(sender, { type: 'pairing-matched', success: false, error: '请输入4位数字配对码' });
            return;
        }
        const entry = this._pairingCodes[code];
        if (!entry) {
            this._send(sender, { type: 'pairing-matched', success: false, error: '配对码不存在或已过期' });
            return;
        }
        if (Date.now() > entry.expiresAt) {
            delete this._pairingCodes[code];
            this._send(sender, { type: 'pairing-matched', success: false, error: '配对码已过期' });
            return;
        }
        if (entry.used) {
            this._send(sender, { type: 'pairing-matched', success: false, error: '配对码已被使用' });
            return;
        }
        if (entry.creatorId === sender.id) {
            this._send(sender, { type: 'pairing-matched', success: false, error: '不能使用自己创建的配对码' });
            return;
        }
        entry.used = true;
        const creatorPeer = this._findPeer(entry.creatorId);
        this._send(sender, {
            type: 'pairing-matched',
            success: true,
            pairingCode: code,
            peer: {
                id: entry.creatorId,
                fingerprint: entry.creatorFingerprint,
                alias: entry.creatorAlias,
                deviceModel: entry.creatorDeviceModel,
                deviceType: entry.creatorDeviceType
            }
        });
        if (creatorPeer) {
            this._send(creatorPeer, {
                type: 'pairing-matched',
                success: true,
                pairingCode: code,
                peer: {
                    id: sender.id,
                    fingerprint: sender.fingerprint || '',
                    alias: sender.name.displayName,
                    deviceModel: sender.deviceModel || '',
                    deviceType: sender.name.type || ''
                }
            });
        }
        delete this._pairingCodes[code];
        console.log('Pairing matched via code:', code, 'creator:', entry.creatorId, 'joiner:', sender.id);
    }

    _handleRadarBroadcast(sender, message) {
        const payload = message.payload || message.data || {};
        this._radarPool[sender.id] = {
            deviceId: sender.id,
            fingerprint: sender.fingerprint || '',
            alias: payload.alias || sender.name.displayName,
            deviceModel: payload.deviceModel || sender.deviceModel || '',
            deviceType: payload.deviceType || sender.name.type || '',
            ipRange: payload.ipRange || sender.ipRange || '',
            ipCity: payload.ipCity || sender.ipCity || '',
            ip: sender.ip,
            userId: sender.userId || '',
            lastBroadcast: Date.now()
        };
        this._send(sender, { type: 'radar-broadcast', success: true });
    }

    _handleRadarScan(sender, message) {
        const payload = message.payload || message.data || {};
        const myIpRange = payload.ipRange || sender.ipRange || '';
        const myIpCity = payload.ipCity || sender.ipCity || '';
        const devices = [];
        for (const deviceId in this._radarPool) {
            const entry = this._radarPool[deviceId];
            if (deviceId === sender.id) continue;
            if (Date.now() - entry.lastBroadcast > 30000) continue;
            let matchType = 'remote';
            if (sender.userId && entry.userId && sender.userId === entry.userId) {
                matchType = 'my-device';
            } else if (myIpRange && entry.ipRange && myIpRange === entry.ipRange) {
                matchType = 'same-network';
            } else if (myIpCity && entry.ipCity && myIpCity === entry.ipCity) {
                matchType = 'same-city';
            }
            devices.push({
                id: entry.deviceId,
                fingerprint: entry.fingerprint,
                alias: entry.alias,
                deviceModel: entry.deviceModel,
                deviceType: entry.deviceType,
                ipCity: entry.ipCity,
                matchType: matchType
            });
        }
        devices.sort((a, b) => {
            const order = { 'my-device': 0, 'same-network': 1, 'same-city': 2, 'remote': 3 };
            return (order[a.matchType] || 4) - (order[b.matchType] || 4);
        });
        this._send(sender, { type: 'radar-devices', devices: devices });
    }

    _handleScreenShareRequest(sender, message) {
        const targetId = message.to;
        if (!targetId) return;
        const targetPeer = this._resolveTarget(sender, targetId);
        if (!targetPeer) {
            this._send(sender, {
                type: 'screen-share-response',
                from: targetId,
                success: false,
                error: 'Target device not found or offline'
            });
            return;
        }
        const payload = message.payload || message.data || {};
        const direction = payload.direction || 'view';
        this._send(targetPeer, {
            type: 'screen-share-request',
            from: sender.fingerprint || sender.id,
            fromPeerId: sender.id,
            direction: direction,
            requestId: Date.now().toString(36) + Math.random().toString(36).substr(2),
            timestamp: Date.now()
        });
        console.log('Screen share request:', sender.id, '->', targetId, 'direction:', direction);
    }

    _handleScreenShareAccept(sender, message) {
        const targetId = message.to;
        if (!targetId) return;
        const targetPeer = this._resolveTarget(sender, targetId);
        if (!targetPeer) {
            this._send(sender, { type: 'screen-share-response', success: false, error: 'Target device not found' });
            return;
        }
        const payload = message.payload || message.data || {};
        const shareKey = [sender.id, targetId].sort().join(':');
        this._activeScreenShares[shareKey] = {
            sharer: payload.direction === 'share' ? sender.id : targetId,
            viewer: payload.direction === 'share' ? targetId : sender.id,
            direction: payload.direction || 'view',
            startedAt: Date.now()
        };
        this._send(targetPeer, {
            type: 'screen-share-accept',
            from: sender.fingerprint || sender.id,
            fromPeerId: sender.id,
            direction: payload.direction || 'view',
            timestamp: Date.now()
        });
        console.log('Screen share accepted:', sender.id, '<->', targetId);
    }

    _handleScreenShareReject(sender, message) {
        const targetId = message.to;
        if (!targetId) return;
        const targetPeer = this._resolveTarget(sender, targetId);
        if (targetPeer) {
            this._send(targetPeer, {
                type: 'screen-share-reject',
                from: sender.fingerprint || sender.id,
                fromPeerId: sender.id,
                timestamp: Date.now()
            });
        }
        console.log('Screen share rejected:', sender.id, 'rejected request from', targetId);
    }

    _handleScreenShareStop(sender, message) {
        const targetId = message.to;
        if (!targetId) return;
        const shareKey = [sender.id, targetId].sort().join(':');
        delete this._activeScreenShares[shareKey];
        const targetPeer = this._resolveTarget(sender, targetId);
        if (targetPeer) {
            this._send(targetPeer, {
                type: 'screen-share-stop',
                from: sender.fingerprint || sender.id,
                fromPeerId: sender.id,
                timestamp: Date.now()
            });
        }
        console.log('Screen share stopped:', sender.id, '<->', targetId);
    }

    _joinRoom(peer) {
        if (!this._rooms[peer.ip]) {
            this._rooms[peer.ip] = {};
        }

        for (const otherPeerId in this._rooms[peer.ip]) {
            const otherPeer = this._rooms[peer.ip][otherPeerId];
            this._send(otherPeer, {
                type: 'peer-joined',
                peer: peer.getInfo()
            });
        }

        const otherPeers = [];
        for (const otherPeerId in this._rooms[peer.ip]) {
            otherPeers.push(this._rooms[peer.ip][otherPeerId].getInfo());
        }

        this._send(peer, {
            type: 'peers',
            peers: otherPeers
        });

        this._rooms[peer.ip][peer.id] = peer;

        if (peer.userId) {
            if (!this._userIdIndex[peer.userId]) {
                this._userIdIndex[peer.userId] = new Set();
            }
            this._userIdIndex[peer.userId].add(peer.id);
        }
    }

    _leaveRoom(peer) {
        if (!this._rooms[peer.ip] || !this._rooms[peer.ip][peer.id]) return;
        this._cancelKeepAlive(this._rooms[peer.ip][peer.id]);

        if (peer.canvasRoomId && this._canvasRooms[peer.canvasRoomId]) {
            this._canvasRooms[peer.canvasRoomId].delete(peer.id);
            for (const peerId of this._canvasRooms[peer.canvasRoomId]) {
                const otherPeer = this._findPeer(peerId);
                if (otherPeer) {
                    this._send(otherPeer, {
                        type: 'canvas-leave',
                        from: peer.fingerprint || peer.id,
                        payload: { canvasId: peer.canvasRoomId }
                    });
                }
            }
            if (this._canvasRooms[peer.canvasRoomId].size === 0) {
                delete this._canvasRooms[peer.canvasRoomId];
            }
            peer.canvasRoomId = null;
        }

        if (peer.fingerprint && this._fingerprintIndex[peer.fingerprint] === peer.id) {
            delete this._fingerprintIndex[peer.fingerprint];
        }

        delete this._rooms[peer.ip][peer.id];

        if (peer.userId && this._userIdIndex[peer.userId]) {
            this._userIdIndex[peer.userId].delete(peer.id);
            if (this._userIdIndex[peer.userId].size === 0) {
                delete this._userIdIndex[peer.userId];
            }
        }

        if (this._radarPool[peer.id]) {
            delete this._radarPool[peer.id];
        }

        for (const shareKey in this._activeScreenShares) {
            const share = this._activeScreenShares[shareKey];
            if (share.sharer === peer.id || share.viewer === peer.id) {
                const otherPeerId = share.sharer === peer.id ? share.viewer : share.sharer;
                const otherPeer = this._findPeer(otherPeerId);
                if (otherPeer) {
                    this._send(otherPeer, {
                        type: 'screen-share-stop',
                        from: peer.fingerprint || peer.id,
                        fromPeerId: peer.id,
                        reason: 'peer-disconnected',
                        timestamp: Date.now()
                    });
                }
                delete this._activeScreenShares[shareKey];
            }
        }

        for (const code in this._pairingCodes) {
            if (this._pairingCodes[code].creatorId === peer.id) {
                delete this._pairingCodes[code];
            }
        }

        peer.socket.terminate();
        if (!Object.keys(this._rooms[peer.ip]).length) {
            delete this._rooms[peer.ip];
        } else {
            for (const otherPeerId in this._rooms[peer.ip]) {
                const otherPeer = this._rooms[peer.ip][otherPeerId];
                this._send(otherPeer, { type: 'peer-left', peerId: peer.id });
            }
        }
    }

    _send(peer, message) {
        if (!peer) return;
        if (this._wss.readyState !== this._wss.OPEN) return;
        message = JSON.stringify(message);
        peer.socket.send(message, error => '');
    }

    _keepAlive(peer) {
        this._cancelKeepAlive(peer);
        var timeout = 30000;
        if (!peer.lastBeat) {
            peer.lastBeat = Date.now();
        }
        if (Date.now() - peer.lastBeat > 2 * timeout) {
            this._leaveRoom(peer);
            return;
        }

        this._send(peer, { type: 'ping' });

        peer.timerId = setTimeout(() => this._keepAlive(peer), timeout);
    }

    _cancelKeepAlive(peer) {
        if (peer && peer.timerId) {
            clearTimeout(peer.timerId);
        }
    }
}



class Peer {

    constructor(socket, request) {
        this.socket = socket;

        this._setIP(request);
        this._setPeerId(request);
        this.rtcSupported = request.url.indexOf('webrtc') > -1;
        this._setName(request);

        this.userId = '';
        this.fingerprint = '';
        this.ipCity = '';
        this.ipRange = '';
        this.deviceModel = '';
        this.platform = '';
        this.canvasRoomId = null;

        this.timerId = 0;
        this.lastBeat = Date.now();
    }

    _setIP(request) {
        if (request.headers['x-forwarded-for']) {
            this.ip = request.headers['x-forwarded-for'].split(/\s*,\s*/)[0];
        } else {
            this.ip = request.connection.remoteAddress;
        }
        if (this.ip == '::1' || this.ip == '::ffff:127.0.0.1') {
            this.ip = '127.0.0.1';
        }
    }

    _setPeerId(request) {
        if (request.peerId) {
            this.id = request.peerId;
        } else {
            this.id = request.headers.cookie.replace('peerid=', '');
        }
    }

    toString() {
        return `<Peer id=${this.id} ip=${this.ip} userId=${this.userId} rtcSupported=${this.rtcSupported}>`
    }

    _setName(req) {
        let ua = parser(req.headers['user-agent']);

        let deviceName = '';
        
        if (ua.os && ua.os.name) {
            deviceName = ua.os.name.replace('Mac OS', 'Mac') + ' ';
        }
        
        if (ua.device.model) {
            deviceName += ua.device.model;
        } else {
            deviceName += ua.browser.name;
        }

        if(!deviceName)
            deviceName = 'Unknown Device';

        const displayName = uniqueNamesGenerator({
            length: 2,
            separator: ' ',
            dictionaries: [colors, animals],
            style: 'capital',
            seed: this.id.hashCode()
        })

        this.name = {
            model: ua.device.model,
            os: ua.os.name,
            browser: ua.browser.name,
            type: ua.device.type,
            deviceName,
            displayName
        };
    }

    getInfo() {
        return {
            id: this.id,
            name: this.name,
            rtcSupported: this.rtcSupported,
            userId: this.userId,
            ipCity: this.ipCity,
            deviceModel: this.deviceModel,
            platform: this.platform
        }
    }

    static uuid() {
        let uuid = '',
            ii;
        for (ii = 0; ii < 32; ii += 1) {
            switch (ii) {
                case 8:
                case 20:
                    uuid += '-';
                    uuid += (Math.random() * 16 | 0).toString(16);
                    break;
                case 12:
                    uuid += '-';
                    uuid += '4';
                    break;
                case 16:
                    uuid += '-';
                    uuid += (Math.random() * 4 | 8).toString(16);
                    break;
                default:
                    uuid += (Math.random() * 16 | 0).toString(16);
            }
        }
        return uuid;
    };
}

Object.defineProperty(String.prototype, 'hashCode', {
  value: function() {
    var hash = 0, i, chr;
    for (i = 0; i < this.length; i++) {
      chr   = this.charCodeAt(i);
      hash  = ((hash << 5) - hash) + chr;
      hash |= 0;
    }
    return hash;
  }
});

const server = new SnapdropServer(process.env.PORT || 3000);