call-sdk/packages/adapter-ameyo/lib/assets/js/ajaxClient.ts

// eslint-disable-next-line @typescript-eslint/ban-ts-comment
//@ts-nocheck

import {extractAndProcessEvents} from "../../callStateManager.ts";

export enum MessagingType {
    ON_AMEYO_CALL_INCOMING = 'onAmeyoCallIncoming',
    ON_AMEYO_CALL_ACCEPTED = 'onAmeyoCallAccepted',
    ON_AMEYO_CALL_DISCONNECTED = 'onAmeyoCallDisconnected',
    ON_AMEYO_AGENT_ON_BREAK = 'onAmeyoAgentOnBreak',
    ON_AMEYO_FORCED_LOGOUT = 'onAmeyoForcedLogout',
    ON_AMEYO_CALL_TRANSFER = 'onAmeyoCallTransfer',
}


let pushConnectionIndex = 0;
const pushHistory = [];
let sizeOfHistory = 5;

let isConnectionEstablished = false;
let shouldStopConnection = false;

let isAttempting = false;

let connStart;
let connEnd;
let conAttemptFailed = 0;

let reConnectionCount = 0;

let baseUrl;
let sessionId;

let pushConnectionHealthTimer = null;
let lastPushReceivedTime = '';
const monitorPushTime = 60 * 1000;

//call the above function to create the XMLHttpRequest object
let http = createRequestObject();


function createRequestObject() {
    let tmpXmlHttpObject;

    // depending on what the browser supports, use the right way to create the
    // XMLHttpRequest object
    if (window.XMLHttpRequest) {
        // Mozilla, Safari would use this method ...
        tmpXmlHttpObject = new XMLHttpRequest();
    } else if (window.ActiveXObject) {
        // IE would use this method ...
        tmpXmlHttpObject = new ActiveXObject('Microsoft.XMLHTTP');
    }

    return tmpXmlHttpObject;
}

//This is called after login to start attempting push connection through post request
export function establishPushConnection(url, session) {
    baseUrl = url;
    sessionId = session;
    makePostRequest(baseUrl, sessionId);
}

//This should be after logout to stop re-establishing push connection
function stopPushConnection() {
    shouldStopConnection = true;
    if (http) {
        http.abort();
    }
}

function reset() {
    pushConnectionIndex = 0;
    sizeOfHistory = 5;
    isConnectionEstablished = false;
    shouldStopConnection = false;
    isAttempting = false;
    conAttemptFailed = 0;
    reConnectionCount = 0;
}

function processResponse() {
    // check if the response has been received from the server
    if (http.readyState == 3 || http.readyState == 4) {
        reConnectionCount = 0;

        if (http.status == 200) {
            changeConnectionEstablishState(true);
        }
        // read and assign the response from the server
        const pushResponse = http.responseText.substring(pushConnectionIndex, http.responseText.length);
        pushConnectionIndex = http.responseText.length;

        // process push received one at a time
        processPush(pushResponse);

        // in this case simply assign the response to the contents of the <div>
        // on the page.
        // document.getElementById('description').innerHTML = http.responseText;

        const currentTime = new Date();
        lastPushReceivedTime = currentTime.getTime();
    }

    // Note :This sample does not consider content boundary in the multipart
    // response
}

function processPush(pushResponse) {
    extractAndProcessEvents(pushResponse);
}

function makePostRequest(url, session) {
    if (shouldStopConnection == true) {
        console.log('should stop connection');
        return;
    }

    reConnectionCount++;
    if (reConnectionCount > 10) {
        console.log('reconnection count reached not reconnecting');
        return;
    }

    if (isConnectionEstablished) {
        console.log('connection is already established , so not establishing a connection');
        return;
    }

    if (conAttemptFailed > 5) {
        console.log('continous attempt failed limit reached');
        console.error('Unable to connect to the server. Please login after some time.');
        return;
    }

    if (isAttempting) {
        return;
    } else {
        isAttempting = true;
    }

    connStart = new Date();

    http = createRequestObject();

    const listenerName = `webcore_${Date.now()}`; //window.listenerName ;
    window.listenerName = listenerName;
    let lastProcessedSeq = -1; //window.lastProcessedPush;

    let finalUrl = url;
    const tempSession = session;

    if (typeof lastProcessedSeq == 'undefined' || lastProcessedSeq == null) {
        lastProcessedSeq = -1;
    }

    if (typeof pushConnectionHealthTimer != 'undefined' && pushConnectionHealthTimer != null) {
        clearInterval(pushConnectionHealthTimer);
        pushConnectionHealthTimer = null;
    }

    finalUrl = finalUrl + '&listener-name=' + listenerName + '&lastProcessedPush=' + lastProcessedSeq;
    console.log(
        'going to create push connection with seq:- ' +
        lastProcessedSeq +
        ' listener name:- ' +
        listenerName
    );
    console.log('final url ', finalUrl);
    // make a connection to the server ... specifying that you intend to make a
    // GET request
    // to the server. Specifiy the page name and the URL parameters to send
    http.open('POST', finalUrl, true);
    http.setRequestHeader('sessionId', tempSession);
    pushConnectionIndex = 0;
    // assign a handler for the response Origin null is not allowed by
    // Access-Control-Allow-Origin.
    http.onreadystatechange = processResponse;

    http.addEventListener('loadend', function checkPushEventHealth(e) {
        connEnd = new Date();
        const seconds = (connEnd.getTime() - connStart.getTime()) / 1000;

        if (seconds < 5) {
            conAttemptFailed++;
        } else {
            conAttemptFailed = 0;
        }

        isAttempting = false;
        changeConnectionEstablishState(false);
        makePostRequest(baseUrl, sessionId);
    });
    http.addEventListener('loadstart', function createCheckPushHealthTimer() {
        if (typeof pushConnectionHealthTimer == 'undefined' || pushConnectionHealthTimer == null) {
            pushConnectionHealthTimer = window.setInterval(
                function () {
                    checkAjaxPushConnectionHealth();
                },
                3 * 1000 // 3 seconds
            );
        }
    });
    // actually send the request to the server
    http.send();
}

function checkAjaxPushConnectionHealth() {
    if (typeof http == 'undefined' || http == null) {
        return;
    }
    const time = new Date();
    const timeDiff = time.getTime() - lastPushReceivedTime;
    if (timeDiff >= monitorPushTime) {
        resetConn();
    }
}

function resetConn() {
    console.log('going to reset connection');
    if (http) {
        http.abort();
    }
}

function makeConnectionEstablishHistory(isEstablished) {
    const connectionRecord = new Object();
    connectionRecord.state = isEstablished;
    connectionRecord.dateAdded = new Date();

    console.log(
        'push connection state changed to ' +
        connectionRecord.state +
        ' at ' +
        connectionRecord.dateAdded
    );
    addRecordInHistory(connectionRecord);
}

function addRecordInHistory(record) {
    if (pushHistory != null && record != null) {
        if (pushHistory.length > sizeOfHistory) {
            pushHistory.pop(0);
        }
        pushHistory.push(record);
    }
}

function getPushConnectionHistory() {
    let pushConnectionString = '';
    if (pushHistory != null) {
        for (index = 0; index < pushHistory.length; index++) {
            const connectionRecord = pushHistory[index];
            pushConnectionString =
                pushConnectionString +
                'push connection state changed to ' +
                connectionRecord.state +
                ' at ' +
                connectionRecord.dateAdded +
                ' \n ';
        }
    }
    return pushConnectionString;
}

/**
 * change state of the connection establish. ignore if same state event came.
 *
 * @param isEstablished
 */
function changeConnectionEstablishState(isEstablished) {
    try {
        if (isConnectionEstablished == isEstablished) {
        } else {
            isConnectionEstablished = isEstablished;
            makeConnectionEstablishHistory(isEstablished);
        }
    } catch (err) {
        console.log('unable to log connection establish history');
    }
}