script.js

const calculatorScreen=document.querySelector('.calculator-screen')

const updateScreen=(number)=>{
    calculatorScreen.value = number
}
const numbers=document.querySelectorAll(".number")

numbers.forEach((number)=>{
    number.addEventListener("click",(event)=>{
        inputNumber(event.target.value)
        updateScreen(currentInput)
    })
})

let prevInput='0'
let calculationOperator=''
let currentInput='0'

const inputNumber=(number)=>{
    if(currentInput === '0'){
        currentInput=number
    }else{
        currentInput+=number
    }
}

const inputOperator=(operator)=>{
    prevInput=currentInput
    calculationOperator=operator
    currentInput='0'
}

const operators=document.querySelectorAll(".operator")

operators.forEach((operator)=>{
    operator.addEventListener("click",(event)=>{
        inputOperator(event.target.value)
        // currentInput='0'
    })
})

const equalSign = document.querySelector('.equal-sign')
equalSign.addEventListener('click',()=>{
    calculate()
    updateScreen(currentInput)
    
})

const calculate = ()=>{
    console.log(1)
    let result=0
    
    switch(calculationOperator){
        case '+':
            result=parseInt(prevInput)+parseInt(currentInput)
            break
        case '-':
            result=parseInt(prevInput)-parseInt(currentInput)
            break
        case '*':
            result=parseInt(prevInput)*parseInt(currentInput)
            break
        case '/':
            result=parseInt(prevInput)/parseInt(currentInput)
            break
        default:
            
            return
    }
    currentInput=result.toString()
    calculationOperator=''

}

const clearBtn = document.querySelector('.all-clear')

clearBtn.addEventListener("click",()=>{
 clearAll()
 updateScreen(currentInput)
})

const clearAll=()=>{
    prevInput='0'
    calculationOperator=''
    currentInput='0'
}