// For local development, leave these variables empty
// For production, configure them with correct URLs depending on your deployment
var APPLICATION_SERVER_URL = "";
var LIVEKIT_URL = "";
configureUrls();

var LivekitClient = window.LivekitClient;
var room;

function configureUrls() {
	// If APPLICATION_SERVER_URL is not configured, use default value from local development
	if (!APPLICATION_SERVER_URL) {
		if (window.location.hostname === "localhost") {
			APPLICATION_SERVER_URL = "http://localhost:6080/";
		} else {
			APPLICATION_SERVER_URL = "https://" + window.location.hostname + ":6443/";
		}
	}

	// If LIVEKIT_URL is not configured, use default value from local development
	if (!LIVEKIT_URL) {
		if (window.location.hostname === "localhost") {
			LIVEKIT_URL = "ws://localhost:7880/";
		} else {
			LIVEKIT_URL = "wss://" + window.location.hostname + ":7443/";
		}
	}
}

function joinRoom() {
    var myRoomName = document.getElementById("roomName").value;
    var myUserName = document.getElementById("userName").value;

    // --- 1) Get a Room object ---
    room = new LivekitClient.Room();

    // --- 2) Specify the actions when events take place in the room ---
    // On every new Track received...
    room.on(LivekitClient.RoomEvent.TrackSubscribed, (track, publication, participant) => {
        const element = track.attach();
        element.id = track.sid;
        element.className = "removable";
        document.getElementById("video-container").appendChild(element);

        if (track.kind === "video") {
            appendUserData(element, participant.identity);
        }
    });

    // On every new Track destroyed...
    room.on(LivekitClient.RoomEvent.TrackUnsubscribed, (track, publication, participant) => {
        track.detach();
        document.getElementById(track.sid)?.remove();
		
        if (track.kind === "video") {
            removeUserData(participant);
        }
    });

    // --- 3) Connect to the room with a valid access token ---
    // Get a token from the application backend
    getToken(myRoomName, myUserName).then((token) => {
        // First param is the LiveKit server URL. Second param is the access token
        room.connect(LIVEKIT_URL, token)
            .then(() => {
                // --- 4) Set page layout for active call ---
                document.getElementById("room-title").innerText = myRoomName;
                document.getElementById("join").style.display = "none";
                document.getElementById("room").style.display = "block";

                // --- 5) Publish your local tracks ---
                room.localParticipant.setMicrophoneEnabled(true);
                room.localParticipant.setCameraEnabled(true).then((publication) => {
                    const element = publication.track.attach();
                    document.getElementById("video-container").appendChild(element);
                    initMainVideo(element, myUserName);
                    appendUserData(element, myUserName);
                    element.className = "removable";
                });
            })
            .catch((error) => {
                console.log("There was an error connecting to the room:", error.code, error.message);
            });
    });
}

function leaveRoom() {
    // --- 6) Leave the room by calling 'disconnect' method over the Room object ---
    room.disconnect();

    // Removing all HTML elements with user's nicknames.
    // HTML videos are automatically removed when leaving a Room
    removeAllUserData();

    // Back to 'Join room' page
    document.getElementById("join").style.display = "block";
    document.getElementById("room").style.display = "none";
}

window.onbeforeunload = function () {
    if (room) room.disconnect();
};

// APPLICATION SPECIFIC METHODS
window.addEventListener("load", function () {
    generateParticipantInfo();
});

function generateParticipantInfo() {
    document.getElementById("roomName").value = "RoomA";
    document.getElementById("userName").value = "Participant" + Math.floor(Math.random() * 100);
}

function appendUserData(videoElement, participantIdentity) {
    var dataNode = document.createElement("div");
    dataNode.className = "removable";
    dataNode.id = "data-" + participantIdentity;
    dataNode.innerHTML = "<p>" + participantIdentity + "</p>";
    videoElement.parentNode.insertBefore(dataNode, videoElement.nextSibling);
    addClickListener(videoElement, participantIdentity);
}

function removeUserData(participant) {
    var dataNode = document.getElementById("data-" + participant.identity);
    dataNode?.parentNode.removeChild(dataNode);
}

function removeAllUserData() {
    var elementsToRemove = document.getElementsByClassName("removable");
    while (elementsToRemove[0]) {
        elementsToRemove[0].parentNode.removeChild(elementsToRemove[0]);
    }
}

function addClickListener(videoElement, userData) {
    videoElement.addEventListener("click", function () {
        var mainVideo = $("#main-video video").get(0);
        if (mainVideo.srcObject !== videoElement.srcObject) {
            $("#main-video").fadeOut("fast", () => {
                $("#main-video p").html(userData);
                mainVideo.srcObject = videoElement.srcObject;
                $("#main-video").fadeIn("fast");
            });
        }
    });
}

function initMainVideo(videoElement, userData) {
    document.querySelector("#main-video video").srcObject = videoElement.srcObject;
    document.querySelector("#main-video p").innerHTML = userData;
    document.querySelector("#main-video video")["muted"] = true;
}

/**
 * --------------------------------------------
 * GETTING A TOKEN FROM YOUR APPLICATION SERVER
 * --------------------------------------------
 * The methods below request the creation of a Token to
 * your application server. This keeps your OpenVidu deployment secure.
 *
 * In this sample code, there is no user control at all. Anybody could
 * access your application server endpoints! In a real production
 * environment, your application server must identify the user to allow
 * access to the endpoints.
 */
function getToken(roomName, participantName) {
    return new Promise((resolve, reject) => {
        $.ajax({
            type: "POST",
            url: APPLICATION_SERVER_URL + "token",
            data: JSON.stringify({
                roomName,
                participantName,
            }),
            headers: { "Content-Type": "application/json" },
            success: (token) => resolve(token),
            error: (error) => reject(error),
        });
    });
}