// webrtcManager.js (수정본 — STUN 없이 ICE만)

export class WebRTCManager {
    constructor(signalUrl) {
        this.pc = null;
        this.localStream = null;
        this.remoteStream = null;
        this.onRemoteStream = null;
        this.signalUrl = signalUrl; // 시그널링 서버 주소
        this.ws = null;
        this.myId = null;
        this.peerId = null; // 상대방 ID (수동 입력 또는 자동 할당)
    }

    async init() {
        await this.requestMicPermission()
        this.setupSignaling();
    }

    async requestMicPermission() {
        try {
            const stream = await navigator.mediaDevices.getUserMedia({audio: true});
            console.log('✅ 마이크 접근 성공');
            stream.getTracks().forEach(track => track.stop()); // 임시로 열었다가 닫음
            return true;
        } catch (err) {
            console.error('❌ 마이크 권한 거부 또는 장치 없음:', err.message);
            alert('마이크 접근이 필요합니다. 브라우저 설정에서 마이크 권한을 허용해주세요.');
            return false;
        }
    }

    setupSignaling() {
        this.ws = new WebSocket(this.signalUrl);

        this.ws.onopen = () => {
            console.log('🔌 시그널링 서버 연결됨');
        };

        this.ws.onmessage = (event) => {
            const msg = JSON.parse(event.data);
            if (msg.type === 'your-id') {
                this.myId = msg.id;
                console.log('내 ID:', this.myId);
            } else if (msg.type === 'offer') {
                this.setRemoteDescription(msg.sdp);
                this.addIceCandidateQueue.forEach(c => this.pc.addIceCandidate(c));
                this.addIceCandidateQueue = [];
            } else if (msg.type === 'answer') {
                this.setRemoteDescription(msg.sdp);
            } else if (msg.type === 'candidate') {
                this.addIceCandidate(msg.candidate);
            }
        };
    }

    createPeerConnection() {
        // ✅ STUN 서버 없이 빈 설정 — 인트라넷 내부 IP로 직접 연결
        this.pc = new RTCPeerConnection({});

        this.localStream.getTracks().forEach(track => {
            this.pc.addTrack(track, this.localStream);
        });

        this.pc.ontrack = (event) => {
            this.remoteStream = event.streams[0];
            if (this.onRemoteStream) this.onRemoteStream(this.remoteStream);
        };

        // ICE Candidate → 시그널링으로 전송
        this.pc.onicecandidate = (event) => {
            if (event.candidate) {
                console.log('📤 ICE Candidate:', event.candidate.candidate);
                this.ws.send(JSON.stringify({
                    target: this.peerId,
                    type: 'candidate',
                    candidate: event.candidate
                }));
            }
        };
    }

    async createOffer(targetId) {
        this.peerId = targetId;
        this.createPeerConnection();
        const offer = await this.pc.createOffer();
        await this.pc.setLocalDescription(offer);

        this.ws.send(JSON.stringify({
            target: targetId,
            type: 'offer',
            sdp: offer
        }));
        console.log('📤 Offer 전송 완료');
    }

    async setRemoteDescription(sdp) {
        await this.pc.setRemoteDescription(new RTCSessionDescription(sdp));
        if (sdp.type === 'offer') {
            const answer = await this.pc.createAnswer();
            await this.pc.setLocalDescription(answer);
            this.ws.send(JSON.stringify({
                target: this.peerId || 'unknown',
                type: 'answer',
                sdp: answer
            }));
        }
    }

    async addIceCandidate(candidate) {
        if (this.pc && this.pc.remoteDescription) {
            await this.pc.addIceCandidate(new RTCIceCandidate(candidate));
        } else {
            // SDP 설정 전이라면 큐에 저장
            this.addIceCandidateQueue = this.addIceCandidateQueue || [];
            this.addIceCandidateQueue.push(candidate);
        }
    }

    hangup() {
        this.pc?.close();
        this.localStream?.getTracks().forEach(t => t.stop());
        this.ws?.close();
        console.log('📞 통화 종료');
    }
}