const ouputContainer = document.querySelector(`.output-value`);

const prevValueContainer = document.querySelector(`.prev-value`);

const getFormattedNum = (num) => {

if (num == "-") return "";

const n = Number(num);

const value = n.toLocaleString("en-IN");

return value;

};

const getUnFormattedNumber = (num) => {

return Number(num.replace(/,/g, ""));

};

const getOutputNum = () => {

return ouputContainer.innerText;

};

const getHistoryNum = () => {

return prevValueContainer.innerText;

};

const operatorsList = document.querySelectorAll(`.operator`);

Array.from(operatorsList).forEach((operator) =>

operator.addEventListener("click", function () {

if (this.id === "clear") {

prevValueContainer.innerText = "";

ouputContainer.innerText = "";

} else if (this.id === "backspace") {

const num = getUnFormattedNumber(ouputContainer.innerText);

ouputContainer.innerText = getFormattedNum(num.toString().slice(0, -1));

} else {

let output = getOutputNum();

let history = getHistoryNum();

if (output == "" && history != "") {

history = isNaN(history[history.length - 1])

? history.substr(0, history.length - 1)

: history;

}

if (output != "" || history != "") {

output = output === "" ? output : getUnFormattedNumber(output);

history += output;

if (this.id == "=") {

prevValueContainer.innerText = "";

ouputContainer.innerText = getFormattedNum(eval(history));

history = "";

} else {

history += this.id;

ouputContainer.innerText = "";

prevValueContainer.innerText = history;

}

}

}

})

);

const numbersList = document.querySelectorAll(`.number`);

Array.from(numbersList).forEach((operator) =>

operator.addEventListener("click", function () {

let outputVal = getUnFormattedNumber(getOutputNum());

if (outputVal !== NaN) {

const num = outputVal + this.id;

if (num.length > 9) ouputContainer.style.fontSize = "30px";

ouputContainer.innerText = getFormattedNum(num);

}

})

);