feat: add Metered turn server

resources/views/interview/candidate_room.blade.php

@@ -13,6 +13,7 @@
     <!-- Monaco Code Editor Loader & PeerJS Realtime WebRTC Call & SweetAlert2 -->
     <script src="https://cdnjs.cloudflare.com/ajax/libs/monaco-editor/0.45.0/min/vs/loader.min.js"></script>
     <script src="https://unpkg.com/peerjs@1.5.2/dist/peerjs.min.js"></script>
+    <script src="//cdn.metered.ca/sdk/video/1.4.6/sdk.min.js"></script>
     <script src="https://cdn.jsdelivr.net/npm/sweetalert2@11"></script>
     <script src="https://cdnjs.cloudflare.com/ajax/libs/html2canvas/1.4.1/html2canvas.min.js"></script>
 
@@ -1211,7 +1212,7 @@ function showCandidateJoinOption() {
 
             if (joinBtn) joinBtn.style.display = 'none';
 
-            if (!localMediaStream) {
+            if (!localMediaStream || localMediaStream.getVideoTracks().length === 0) {
                 await startCandidateCameraStream();
             }
 
@@ -1224,7 +1225,6 @@ function showCandidateJoinOption() {
                 badge.style.color = '#34d399';
             }
 
-            // Dual 2-Way Connection: Answer incoming call AND establish connection to interviewer peer
             const stream = localMediaStream || new MediaStream();
 
             if (activeCallInstance) {
@@ -1249,8 +1249,7 @@ function showCandidateJoinOption() {
                             const remoteVideo = document.getElementById('interviewer-video');
                             const placeholder = document.getElementById('interviewer-video-placeholder');
                             if (remoteVideo) {
-                                remoteVideo.srcObject = remoteStream;
+                                safePlayMediaStream(remoteVideo, remoteStream);
-                                remoteVideo.play().catch(e => console.log('Remote video play error:', e));
                             }
                             if (placeholder) placeholder.style.display = 'none';
                         });
@@ -1267,7 +1266,60 @@ function showCandidateJoinOption() {
             }
         }
 
-        // 4. WebRTC Real-Time 2-Way Interview Call Setup (Dual Signaling: BroadcastChannel + PeerJS)
+        function safePlayMediaStream(videoElem, stream, isSelf = false) {
+            if (!videoElem || !stream) return;
+            if (isSelf) {
+                videoElem.muted = true;
+            }
+            if (videoElem.srcObject !== stream) {
+                videoElem.srcObject = stream;
+            }
+            const playPromise = videoElem.play();
+            if (playPromise !== undefined) {
+                playPromise.catch(err => {
+                    if (err.name === 'AbortError') {
+                        videoElem.onloadedmetadata = () => {
+                            videoElem.play().catch(() => {});
+                        };
+                    } else if (err.name === 'NotAllowedError') {
+                        videoElem.play().catch(() => {});
+                    } else {
+                        console.log('Media play warning:', err);
+                    }
+                });
+            }
+        }
+
+        // Metered TURN Server Integration (Pre-fetched for seamless WebRTC P2P + TURN relay)
+        const METERED_CREDENTIALS_URL = "https://single-login-system.metered.live/api/v1/turn/credentials?apiKey=ffc9146ac5c2f75d83d7c679d8553a21c8fa";
+        let globalIceServers = [
+            { urls: 'stun:stun.l.google.com:19302' }
+        ];
+        let meteredIceFetchPromise = null;
+
+        function initMeteredIceServers() {
+            if (meteredIceFetchPromise) return meteredIceFetchPromise;
+            meteredIceFetchPromise = fetch(METERED_CREDENTIALS_URL)
+                .then(r => r.json())
+                .then(meteredIce => {
+                    if (Array.isArray(meteredIce) && meteredIce.length > 0) {
+                        globalIceServers = [
+                            { urls: 'stun:stun.l.google.com:19302' },
+                            ...meteredIce.slice(0, 3)
+                        ];
+                    }
+                    return globalIceServers;
+                })
+                .catch(e => {
+                    console.warn('Metered TURN fetch warning:', e);
+                    return globalIceServers;
+                });
+            return meteredIceFetchPromise;
+        }
+
+        // Initiate TURN credentials pre-fetch immediately
+        initMeteredIceServers();
+
         let localMediaStream = null;
         let peerInstance = null;
         let candidatePeerConnection = null;
@@ -1319,7 +1371,22 @@ function showCandidateJoinOption() {
 
             if (msg.type === 'interviewer_joined' || msg.type === 'offer') {
                 latestCallStatus = 'active';
-                triggerCandidateRing(msg.offer || null);
+                if (isCandidateCallConnected && localMediaStream && peerInstance) {
+                    const interviewerPeerId = 'interviewer_' + interviewId;
+                    try {
+                        const outCall = peerInstance.call(interviewerPeerId, localMediaStream);
+                        if (outCall) {
+                            outCall.on('stream', remoteStream => {
+                                const remoteVideo = document.getElementById('interviewer-video');
+                                const placeholder = document.getElementById('interviewer-video-placeholder');
+                                if (remoteVideo) safePlayMediaStream(remoteVideo, remoteStream, false);
+                                if (placeholder) placeholder.style.display = 'none';
+                            });
+                        }
+                    } catch(e) {}
+                } else {
+                    triggerCandidateRing(msg.offer || null);
+                }
             } else if (msg.type === 'answer' && msg.sender !== 'candidate' && candidatePeerConnection) {
                 await candidatePeerConnection.setRemoteDescription(new RTCSessionDescription(msg.answer));
             } else if (msg.type === 'ice-candidate' && msg.sender !== 'candidate' && candidatePeerConnection && msg.candidate) {
@@ -1341,13 +1408,10 @@ function showCandidateJoinOption() {
 
         async function createCandidatePeerConnection() {
             if (candidatePeerConnection) return candidatePeerConnection;
+            await initMeteredIceServers();
 
             candidatePeerConnection = new RTCPeerConnection({
-                iceServers: [
+                iceServers: globalIceServers
-                    { urls: 'stun:stun.l.google.com:19302' },
-                    { urls: 'stun:stun1.l.google.com:19302' },
-                    { urls: 'stun:stun2.l.google.com:19302' }
-                ]
             });
 
             if (localMediaStream) {
@@ -1360,8 +1424,7 @@ function showCandidateJoinOption() {
                 const remoteVideo = document.getElementById('interviewer-video');
                 const placeholder = document.getElementById('interviewer-video-placeholder');
                 if (remoteVideo && event.streams[0]) {
-                    remoteVideo.srcObject = event.streams[0];
+                    safePlayMediaStream(remoteVideo, event.streams[0]);
-                    remoteVideo.play().catch(e => console.log(e));
                 }
                 if (placeholder) placeholder.style.display = 'none';
 
@@ -1373,7 +1436,7 @@ function showCandidateJoinOption() {
                 }
             };
 
-            candidatePeerConnection.onconnectionstatechange = () => {
+            candidatePeerConnection.onconnectionstatechange = async () => {
                 const state = candidatePeerConnection.connectionState;
                 if (state === 'connected') {
                     const badge = document.getElementById('call-status-badge');
@@ -1382,7 +1445,9 @@ function showCandidateJoinOption() {
                         badge.style.background = 'rgba(16,185,129,0.3)';
                         badge.style.color = '#34d399';
                     }
-                } else if (state === 'disconnected' || state === 'failed' || state === 'closed') {
+                } else if (state === 'failed' || state === 'disconnected') {
+                    console.warn('Candidate P2P Connection State:', state);
+                } else if (state === 'closed') {
                     candidateLeaveCall();
                 }
             };
@@ -1411,8 +1476,9 @@ function showCandidateJoinOption() {
             callSigChannel.postMessage({ type: 'answer', answer: answer, sender: 'candidate' });
         }
 
-        function initCandidatePeer() {
+        async function initCandidatePeer() {
             if (typeof Peer === 'undefined') return;
+            await initMeteredIceServers();
 
             const peerId = 'cand_' + interviewId;
             if (peerInstance) {
@@ -1421,11 +1487,7 @@ function initCandidatePeer() {
 
             peerInstance = new Peer(peerId, {
                 config: {
-                    iceServers: [
+                    iceServers: globalIceServers
-                        { urls: 'stun:stun.l.google.com:19302' },
-                        { urls: 'stun:stun1.l.google.com:19302' },
-                        { urls: 'stun:stun2.l.google.com:19302' }
-                    ]
                 }
             });
 
@@ -1441,15 +1503,11 @@ function initCandidatePeer() {
                     triggerCandidateRing();
                 }
 
-                const sendStream = localMediaStream || new MediaStream();
-                call.answer(sendStream);
-
                 call.on('stream', remoteStream => {
                     const remoteVideo = document.getElementById('interviewer-video');
                     const placeholder = document.getElementById('interviewer-video-placeholder');
                     if (remoteVideo) {
-                        remoteVideo.srcObject = remoteStream;
+                        safePlayMediaStream(remoteVideo, remoteStream);
-                        remoteVideo.play().catch(e => console.log('Candidate remote video play error:', e));
                     }
                     if (placeholder) placeholder.style.display = 'none';
 
@@ -1462,33 +1520,57 @@ function initCandidatePeer() {
                         }
                     }
                 });
+                if (localMediaStream && localMediaStream.getVideoTracks().length > 0) {
+                    try { call.answer(localMediaStream); } catch(e) {}
+                }
 
                 call.on('close', () => {
                     candidateLeaveCall();
                 });
             });
+
+            peerInstance.on('error', async err => {
+                console.warn('Candidate PeerJS error:', err);
+                if (err.type === 'peer-unavailable' || err.type === 'network' || err.type === 'webrtc') {
+                    const meteredServers = await fetchMeteredTurnIceServers();
+                    console.log('Re-initializing Candidate PeerJS with Metered TURN Relay Servers...');
+                    if (peerInstance) {
+                        try { peerInstance.destroy(); } catch(e) {}
+                    }
+                    peerInstance = new Peer(peerId, {
+                        config: { iceServers: meteredServers }
+                    });
+                }
+            });
         }
 
         function startCandidateCameraStream() {
             const avatarPlaceholder = document.getElementById('webcam-avatar-placeholder');
 
+            const audioConstraints = {
+                echoCancellation: true,
+                noiseSuppression: true,
+                autoGainControl: true
+            };
+
             return navigator.mediaDevices.getUserMedia({
                 video: {
                     width: { ideal: 1280 },
                     height: { ideal: 720 },
                     facingMode: 'user'
                 },
-                audio: true
+                audio: audioConstraints
             })
-            .catch(() => navigator.mediaDevices.getUserMedia({ video: true, audio: false }))
+            .catch(() => navigator.mediaDevices.getUserMedia({ video: true, audio: audioConstraints }))
+            .catch(() => navigator.mediaDevices.getUserMedia({ video: true, audio: true }))
             .catch(() => navigator.mediaDevices.getUserMedia({ video: false, audio: true }))
+            .catch(() => navigator.mediaDevices.getUserMedia({ video: true, audio: false }))
             .then(stream => {
                 localMediaStream = stream;
                 const vid = document.getElementById('webcam');
                 if (vid) {
                     vid.muted = true;
-                    vid.srcObject = stream;
+                    safePlayMediaStream(vid, stream, true);
-                    vid.play().catch(e => console.log('Candidate webcam play error:', e));
                 }
                 if (avatarPlaceholder) avatarPlaceholder.style.display = 'none';
 

resources/views/interview/index.blade.php

@@ -10,6 +10,7 @@
     <link href="https://fonts.googleapis.com/css2?family=Instrument+Sans:wght@400;500;600;700&family=Outfit:wght@500;600;700&display=swap" rel="stylesheet">
     <script src="https://code.jquery.com/jquery-3.7.1.min.js"></script>
     <script src="https://unpkg.com/peerjs@1.5.2/dist/peerjs.min.js"></script>
+    <script src="//cdn.metered.ca/sdk/video/1.4.6/sdk.min.js"></script>
     <script src="https://cdn.jsdelivr.net/npm/sweetalert2@11"></script>
 
     <style>
@@ -1292,7 +1293,6 @@ function openReviewModal(id, name, uid, autoJoinCall = false) {
 
             document.getElementById('review-modal').classList.add('active');
             resetZoomScreen();
-            initInterviewerPeer();
             switchIdeTab('code');
 
             subscribeLiveSync(id);
@@ -1686,25 +1686,106 @@ function blockCandidateAction() {
             }
         }
 
-        function initInterviewerPeer() {
+        // Metered TURN Server Integration (Pre-fetched for seamless WebRTC P2P + TURN relay)
+        const METERED_CREDENTIALS_URL = "https://single-login-system.metered.live/api/v1/turn/credentials?apiKey=ffc9146ac5c2f75d83d7c679d8553a21c8fa";
+        let globalIceServers = [
+            { urls: 'stun:stun.l.google.com:19302' }
+        ];
+        let meteredIceFetchPromise = null;
+
+        function initMeteredIceServers() {
+            if (meteredIceFetchPromise) return meteredIceFetchPromise;
+            meteredIceFetchPromise = fetch(METERED_CREDENTIALS_URL)
+                .then(r => r.json())
+                .then(meteredIce => {
+                    if (Array.isArray(meteredIce) && meteredIce.length > 0) {
+                        globalIceServers = [
+                            { urls: 'stun:stun.l.google.com:19302' },
+                            ...meteredIce.slice(0, 3)
+                        ];
+                    }
+                    return globalIceServers;
+                })
+                .catch(e => {
+                    console.warn('Metered TURN fetch warning:', e);
+                    return globalIceServers;
+                });
+            return meteredIceFetchPromise;
+        }
+
+        // Initiate TURN credentials pre-fetch immediately
+        initMeteredIceServers();
+
+        function safePlayMediaStream(videoElem, stream, isSelf = false) {
+            if (!videoElem || !stream) return;
+            if (isSelf) {
+                videoElem.muted = true;
+            }
+            if (videoElem.srcObject !== stream) {
+                videoElem.srcObject = stream;
+            }
+            const playPromise = videoElem.play();
+            if (playPromise !== undefined) {
+                playPromise.catch(err => {
+                    if (err.name === 'AbortError') {
+                        videoElem.onloadedmetadata = () => {
+                            videoElem.play().catch(() => {});
+                        };
+                    } else if (err.name === 'NotAllowedError') {
+                        videoElem.play().catch(() => {});
+                    } else {
+                        console.log('Media play warning:', err);
+                    }
+                });
+            }
+        }
+
+        async function initInterviewerPeer() {
             if (!currentInterviewId || typeof Peer === 'undefined') return;
+            await initMeteredIceServers();
 
             const peerId = 'interviewer_' + currentInterviewId;
-            interviewerPeer = new Peer(peerId);
+            if (interviewerPeer && !interviewerPeer.destroyed) {
+                try { interviewerPeer.destroy(); } catch(e) {}
+            }
+
+            interviewerPeer = new Peer(peerId, {
+                config: {
+                    iceServers: globalIceServers
+                }
+            });
 
             interviewerPeer.on('open', id => {
                 console.log('Interviewer WebRTC Peer Registered:', id);
             });
 
+            interviewerPeer.on('call', call => {
+                activeCall = call;
+                const sendStream = interviewerLocalStream || new MediaStream();
+                call.answer(sendStream);
+
+                call.on('stream', candRemoteStream => {
+                    const candVid = document.getElementById('interviewer-cand-video');
+                    const placeholder = document.getElementById('cand-video-placeholder');
+                    if (candVid) {
+                        safePlayMediaStream(candVid, candRemoteStream);
+                    }
+                    if (placeholder) placeholder.style.display = 'none';
+
+                    document.getElementById('interviewer-call-status').innerText = 'CONNECTED (LIVE)';
+                    document.getElementById('interviewer-call-status').style.background = 'rgba(16,185,129,0.3)';
+                    document.getElementById('interviewer-call-status').style.color = '#34d399';
+                });
+            });
+
             // Listen for candidate screen share peer stream with STUN iceServers
             const screenPeerId = 'interviewer_screen_' + currentInterviewId;
+            if (screenReceiverPeer && !screenReceiverPeer.destroyed) {
+                try { screenReceiverPeer.destroy(); } catch(e) {}
+            }
             screenReceiverPeer = new Peer(screenPeerId, {
                 config: {
-                    iceServers: [
+                    iceServers: globalIceServers
-                        { urls: 'stun:stun.l.google.com:19302' },
-                        { urls: 'stun:stun1.l.google.com:19302' },
-                        { urls: 'stun:stun2.l.google.com:19302' }
-                    ]
                 }
             });
             screenReceiverPeer.on('call', call => {
@@ -1712,7 +1793,7 @@ function initInterviewerPeer() {
                 call.on('stream', screenStream => {
                     const screenVid = document.getElementById('interviewer-screen-video');
                     const placeholder = document.getElementById('screen-video-placeholder');
-                    if (screenVid) screenVid.srcObject = screenStream;
+                    if (screenVid) safePlayMediaStream(screenVid, screenStream);
                     if (placeholder) placeholder.style.display = 'none';
                 });
             });
@@ -1767,13 +1848,10 @@ function initInterviewerSigChannel() {
 
         async function createInterviewerPeerConnection() {
             if (interviewerPeerConnection) return interviewerPeerConnection;
+            await initMeteredIceServers();
 
             interviewerPeerConnection = new RTCPeerConnection({
-                iceServers: [
+                iceServers: globalIceServers
-                    { urls: 'stun:stun.l.google.com:19302' },
-                    { urls: 'stun:stun1.l.google.com:19302' },
-                    { urls: 'stun:stun2.l.google.com:19302' }
-                ]
             });
 
             if (interviewerLocalStream) {
@@ -1786,8 +1864,7 @@ function initInterviewerSigChannel() {
                 const candVid = document.getElementById('interviewer-cand-video');
                 const placeholder = document.getElementById('cand-video-placeholder');
                 if (candVid && event.streams[0]) {
-                    candVid.srcObject = event.streams[0];
+                    safePlayMediaStream(candVid, event.streams[0]);
-                    candVid.play().catch(e => console.log(e));
                 }
                 if (placeholder) placeholder.style.display = 'none';
 
@@ -1796,6 +1873,20 @@ function initInterviewerSigChannel() {
                 document.getElementById('interviewer-call-status').style.color = '#34d399';
             };
 
+            interviewerPeerConnection.onconnectionstatechange = async () => {
+                const state = interviewerPeerConnection.connectionState;
+                if (state === 'connected') {
+                    const badge = document.getElementById('interviewer-call-status');
+                    if (badge) {
+                        badge.innerText = 'CONNECTED (LIVE)';
+                        badge.style.background = 'rgba(16,185,129,0.3)';
+                        badge.style.color = '#34d399';
+                    }
+                } else if (state === 'failed' || state === 'disconnected') {
+                    console.warn('Interviewer P2P Connection State:', state);
+                }
+            };
+
             interviewerPeerConnection.onicecandidate = (event) => {
                 if (event.candidate) {
                     interviewerSigChannel.postMessage({ type: 'ice-candidate', candidate: event.candidate, sender: 'interviewer' });
@@ -1854,8 +1945,7 @@ function startInterviewerCall(isRejoin = false) {
                 const selfVid = document.getElementById('interviewer-self-video');
                 if (selfVid) {
                     selfVid.muted = true;
-                    selfVid.srcObject = stream;
+                    safePlayMediaStream(selfVid, stream, true);
-                    selfVid.play().catch(e => console.log(e));
                 }
                 document.getElementById('self-video-placeholder').style.display = 'none';
 
@@ -1870,23 +1960,13 @@ function startInterviewerCall(isRejoin = false) {
                     interviewerSigChannel.postMessage({ type: 'interviewer_joined', sender: 'interviewer' });
                 }
 
-                // PeerJS fallback
+                // PeerJS connection
-                const panelistPeerId = 'interviewer_' + currentInterviewId + '_' + Math.floor(Math.random() * 10000);
+                if (!interviewerPeer || interviewerPeer.destroyed) {
-                if (interviewerPeer) {
+                    initInterviewerPeer();
-                    try { interviewerPeer.destroy(); } catch(e) {}
                 }
 
-                interviewerPeer = new Peer(panelistPeerId, {
+                const makePeerJSCall = () => {
-                    config: {
+                    if (!interviewerPeer || interviewerPeer.destroyed) return;
-                        iceServers: [
-                            { urls: 'stun:stun.l.google.com:19302' },
-                            { urls: 'stun:stun1.l.google.com:19302' },
-                            { urls: 'stun:stun2.l.google.com:19302' }
-                        ]
-                    }
-                });
-
-                interviewerPeer.on('open', () => {
                     const candPeerId = 'cand_' + currentInterviewId;
                     activeCall = interviewerPeer.call(candPeerId, stream);
 
@@ -1895,37 +1975,48 @@ function startInterviewerCall(isRejoin = false) {
                             const candVid = document.getElementById('interviewer-cand-video');
                             const placeholder = document.getElementById('cand-video-placeholder');
                             if (candVid) {
-                                candVid.srcObject = candRemoteStream;
+                                safePlayMediaStream(candVid, candRemoteStream);
-                                candVid.play().catch(e => console.log('Interviewer video play error:', e));
                             }
                             if (placeholder) placeholder.style.display = 'none';
 
                             candRemoteStream.onaddtrack = () => {
                                 if (placeholder) placeholder.style.display = 'none';
-                                if (candVid) candVid.play().catch(e => {});
+                                if (candVid) safePlayMediaStream(candVid, candRemoteStream);
                             };
 
                             document.getElementById('interviewer-call-status').innerText = 'CONNECTED (LIVE)';
                             document.getElementById('interviewer-call-status').style.background = 'rgba(16,185,129,0.3)';
                             document.getElementById('interviewer-call-status').style.color = '#34d399';
                         });
-
-                        activeCall.on('close', () => {
-                            console.log('PeerJS media call channel closed. Keeping interviewer local stream active for auto-reconnect.');
-                        });
                     }
-                });
+                };
+
+                if (interviewerPeer && interviewerPeer.open) {
+                    makePeerJSCall();
+                } else if (interviewerPeer) {
+                    interviewerPeer.on('open', makePeerJSCall);
+                }
             };
 
-            navigator.mediaDevices.getUserMedia({ video: true, audio: true })
+            const audioConstraints = {
+                echoCancellation: true,
+                noiseSuppression: true,
+                autoGainControl: true
+            };
+
+            navigator.mediaDevices.getUserMedia({ video: true, audio: audioConstraints })
                 .then(handleStream)
                 .catch(() => {
-                    navigator.mediaDevices.getUserMedia({ video: false, audio: true })
+                    navigator.mediaDevices.getUserMedia({ video: true, audio: true })
                         .then(handleStream)
                         .catch(() => {
-                            navigator.mediaDevices.getUserMedia({ video: true, audio: false })
+                            navigator.mediaDevices.getUserMedia({ video: false, audio: true })
                                 .then(handleStream)
-                                .catch(err => console.log('WebRTC Stream init:', err));
+                                .catch(() => {
+                                    navigator.mediaDevices.getUserMedia({ video: true, audio: false })
+                                        .then(handleStream)
+                                        .catch(err => console.log('WebRTC Stream init:', err));
+                                });
                         });
                 });
         }
@@ -1977,6 +2068,14 @@ function leaveInterviewerCall(isExplicitEnd = true) {
                 try { activeCall.close(); } catch(e) {}
                 activeCall = null;
             }
+            if (interviewerPeer) {
+                try { interviewerPeer.destroy(); } catch(e) {}
+                interviewerPeer = null;
+            }
+            if (screenReceiverPeer) {
+                try { screenReceiverPeer.destroy(); } catch(e) {}
+                screenReceiverPeer = null;
+            }
 
             const candPlace = document.getElementById('cand-video-placeholder');
             const screenPlace = document.getElementById('screen-video-placeholder');