var name;
var connections = {};

const configuration = { 
    iceServers: [{ urls: "stun:stun.l.google.com:19302" }]
}; 

const offerOptions = {
    offerToReceiveAudio: 1,
    offerToReceiveVideo: 1
};

function handleLogin(success) { 
    if (success === false) { 
        alert("try a different username"); 
    } else {

    }
};

async function createPeerConnection(target) {
    console.log("CREATED PEER CONNECTION");
    var connection = new RTCPeerConnection(configuration);
    connections[target] = connection;

    connection.onicecandidate = function(event) { 
        if (event.candidate) { 
            send({ 
                type: "candidate",
                name: name,
                target: target,
                candidate: event.candidate
            });
        }
    };

    connection.onnegotiationneeded = function() { handleNegotiationNeededEvent(target); };
    connection.ontrack = function(event) { handleTrackEvent(event); }
    connection.onsignalingstatechange = function() { handleSignalingStateChangeEvent(connection); }
    connection.oniceconnectionstatechange = function() { handleICEConnectionStateChangeEvent(connection); }
    connection.onicegatheringstatechange = function() { handleICEGatheringStateChangeEvent(connection); }

    //window.setInterval(getConnectionStats, 1000);
}

function handleICEConnectionStateChangeEvent(connection) {
    console.log("ICE CONNECTION CHANGE "+connection.iceConnectionState);
}

function handleICEGatheringStateChangeEvent(connection) {
    console.log("ICE GATHERING CHANGE "+connection.iceGatheringState);
}

async function makeOffer(target) {
    createPeerConnection(target);
    
    var connection = connections[target];

    var offer = await connection.createOffer();
    send({ 
        type: "offer",
        name: name,
        target: target,
        offer: offer 
    }); 
    await connection.setLocalDescription(offer); 
    
}

async function handleOffer(offer, target) { 
    console.log("GOT OFFER FROM "+target);
    await createPeerConnection(target);

    var connection = connections[target];

    await connection.setRemoteDescription(new RTCSessionDescription(offer));

    if (stream) {
        console.log("STREAM DETECTED");
        stream.getTracks().forEach((track) => {
            console.log("ADDED TRACK");
            connection.addTrack(track, stream);
        });
    }
        
    //create an answer to an offer 
    var answer = await connection.createAnswer();
    
    await connection.setLocalDescription(answer); 
            
    send({ 
        type: "answer",
        name: name,
        target: target,
        answer: answer 
    });
};

async function handleAnswer(answer, target) { 
    console.log("GOT ANSWER FROM "+target);
    var connection = connections[target];
    await connection.setRemoteDescription(new RTCSessionDescription(answer)); 
};

async function handleCandidate(candidate, target) { 
    console.log("GOT CANDIDATE FROM "+target);
    var connection = connections[target];
    await connection.addIceCandidate(new RTCIceCandidate(candidate)); 
};

async function handleNegotiationNeededEvent(target) {
    console.log("NEGOTIATION NEEDED FROM "+target);

    var connection = connections[target];
    var offer = await connection.createOffer(offerOptions);
    
    await connection.setLocalDescription(offer);
    
    send({
        type: "video-offer",
        name: name,
        target: target,
        sdp: connection.localDescription
    });
}

function handleLeave() {
    connections.foreach( (connection) => {
        connection.close();
        connection.onicecandidate = null; 
        //connection.onaddstream = null; 
        connection = null; 
    });
    connections = {};
    
    remoteVideo.src = null; 
};

function handleUserlist(list) {
    console.log("GOT USER LIST");

}

async function handleVideoOffer(sdp, target) {
    console.log("GOT VIDEO OFFER FROM "+target);
    await createPeerConnection(target);
    var connection = connections[target];
    await connection.setRemoteDescription(new RTCSessionDescription(sdp))

    if (stream) {
        console.log("STREAM DETECTED");
        stream.getTracks().forEach((track) => {
            console.log("ADDED TRACK");
            connection.addTrack(track, stream);
        });
    }

    var answer = await connection.createAnswer();
    await connection.setLocalDescription(answer); 

    send({
        type: "video-answer",
        name: name,
        target: target,
        sdp: answer
    });    
}

async function handleVideoAnswer(sdp, target) {
    console.log("GOT VIDEO ANSWER FROM "+target);

    var connection = connections[target];
    await connection.setRemoteDescription(new RTCSessionDescription(sdp));
}

async function handleSignalingStateChangeEvent(connection) {
    console.log("STATE CHANGED TO : " + connection.signalingState);
    switch(connection.signalingState) {
        case "closed":
            await connection.close();
            break;
    }
}

function handleTrackEvent(event) {
    console.log("GOT TRACK");
    remoteVideo.srcObject = event.streams[0];
    //document.getElementById("hangup-button").disabled = false;
}

function getConnectionStats() {
    for ([connection, target] in connections) {
        console.log("[" + target + "] " + connection.connectionState);
    }
}