// Set previous ticker
var previousTicker = [];

async function updateTicker(firstTime){
    
    firstTime = firstTime || null;
    
    var myDiv = document.getElementsByClassName('market-ticker');

    if(myDiv.length > 0) {

        var element;
        var image;
        var price;
        var difference = 0;
        
        var screenWidth = window.innerWidth;
        
        var myHeaders = new Headers();

        var myInit = { 
                    method: 'GET',
                    headers: myHeaders,
                    mode: 'cors',
                    cache: 'default'
                };

        fetch('https://www.binance.me/api/v3/ticker/price?symbols=["BTCUSDT","ETHUSDT","XRPUSDT","LTCUSDT","SOLUSDT","BNBUSDT"]',myInit)
        .then( response=>response.json() )
        .then( data=>{ 
            
            // Clean containers
            for(var a = 0; a < myDiv.length; a++) {
                
                myDiv[a].innerHTML = '';

                for(var z = 0; z < data.length; z++) {
                    
                    if(data[z]['symbol'] !== undefined) {
                        
                        // Create element
                        element = document.createElement('strong');
                        element.className = 'show-inline-block padding-small small';
                        
                        // Coin
                        coin = data[z]['symbol'].replace('USDT', '');
                        
                        // Image
                        image = document.createElement('img');
                        image.src = '/modules/market-reports/svg/' + coin + '.svg';
                        image.style.height = '15px';
                        image.style.width = '15px';
                        image.setAttribute('width', '15');
                        image.setAttribute('height', '15');
                        image.setAttribute('alt', 'Logo of cryptocurrency' + coin);
                        
                        // Price
                        price = document.createElement('span');
                        price.innerHTML = ' \$' + parseFloat(data[z]['price']);
                        
                        if(previousTicker[coin] !== 'undefined') {
                            difference = previousTicker[coin] - parseFloat(data[z]['price']);
                            if(difference < 0) {
                                price.className = 'text-green';
                                price.innerHTML = price.innerHTML + ' ↑'
                            } else if(difference > 0) {
                                price.className = 'text-red';
                                price.innerHTML = price.innerHTML + ' ↓'
                            } else {
                                price.innerHTML = price.innerHTML + ' ='
                            }
                        }
                        
                        // Append children to element
                        element.appendChild(image);
                        element.appendChild(price);
                        
                        // Stop loop at 3 pairs on small screens
                        if(screenWidth < 600) {
                            if(z == 2) {
                                z = 999;
                            }
                        }
                        
                    }
                    
                    // Append element to containers
                    myDiv[a].appendChild(element);
                    
                }
                
            }
            // Update previous ticker
            for(z = 0; z < data.length; z++) {
                if(data[z]['symbol'] !== undefined) {
                    // Coin
                    coin = data[z]['symbol'].replace('USDT', '');
                    previousTicker[coin] = parseFloat(data[z]['price']);
                }
            }
            
        } )
        .then( data=>{ 

            setTimeout(updateTicker, 3333);
            
            if(firstTime == 1) {
                scrollMenu();
            }
            
        });
    }
}

updateTicker(1);