Bitcoin Mining a(ExamTask)

function mining(arr) {
    let oneBitcoinPrice = 11949.16;
    let oneGramGoldPrice = 67.51;
    let firstBitcoinBought = 0;
    let boughtBitcoins = 0;
    let totalMoney = 0;
    let diggedGold = 0;
    let totalBitcoinsBought = 0;
    let day = 0;
    for (let i = 0; i < arr.length; i++) {
        day++;
        if (day % 3 !== 0) {
            diggedGold += Number(arr[i]);
            totalMoney += diggedGold * oneGramGoldPrice;
            if (totalMoney >= oneBitcoinPrice) {
                boughtBitcoins = Math.floor(totalMoney / oneBitcoinPrice );
                if (totalMoney >= oneBitcoinPrice * boughtBitcoins) {
                    totalBitcoinsBought += boughtBitcoins;
                    totalMoney = totalMoney - (oneBitcoinPrice * Math.floor(totalMoney / oneBitcoinPrice));
                    if (firstBitcoinBought === 0) {
                        firstBitcoinBought = day;
                    }
                }
            }
            diggedGold = 0;
            boughtBitcoins = 0;
        }
        else {
            diggedGold += (Number(arr[i]) * 0.7);
            totalMoney += diggedGold * oneGramGoldPrice;
            if (totalMoney >= oneBitcoinPrice) {
                boughtBitcoins = Math.floor(totalMoney / oneBitcoinPrice );
                if (totalMoney >= oneBitcoinPrice * boughtBitcoins) {
                    totalBitcoinsBought += boughtBitcoins;
                    totalMoney = totalMoney - (oneBitcoinPrice * Math.floor(totalMoney / oneBitcoinPrice));
                    if (firstBitcoinBought === 0) {
                        firstBitcoinBought = day;
                    }
                }
            }
            diggedGold = 0;
            boughtBitcoins = 0;
        }
    }
    console.log(`Bought bitcoins: ${totalBitcoinsBought}`);
    if (firstBitcoinBought > 0) {
        console.log(`Day of the first purchased bitcoin: ${firstBitcoinBought}`);
    }
    console.log(`Left money: ${totalMoney.toFixed(2)} lv.`);
}