PRV-Website/calculator.js

let operator;
let operatorSelected = false;
let displayMem;
let equalsPerformed = false;
let fresh = true;

const display = document.getElementById("display");
const operatorDivision = document.getElementById("division");
const operatorMultiplication = document.getElementById("multiplication");
const operatorMinus = document.getElementById("minus");
const operatorPlus = document.getElementById("plus");


function appendToDisplay(input){

    if(input=='.' && display.value.includes('.')){
        return;
    }

    if(operatorSelected){
        if(operator == '+'){
            operatorPlus.style.backgroundColor = "#ff9f0a";
            operatorPlus.style.color = "white";
            
        }else if(operator == '-'){
            operatorMinus.style.backgroundColor = "#ff9f0a";
            operatorMinus.style.color = "white";
            
        }else if(operator == '*'){
            operatorMultiplication.style.backgroundColor = "#ff9f0a";
            operatorMultiplication.style.color = "white";
            
        }else if(operator == '/'){
            operatorDivision.style.backgroundColor = "#ff9f0a";
            operatorDivision.style.color = "white";
            
        }
        
        displayMem = display.value;
        display.value = "";
        operatorSelected = false;
    }
    
    operatorSelected = false;
    display.value += input;
    equalsPerformed = false;
    fresh=false;
    


}

function setOperator(input){
    
    if(operatorSelected){

        operatorPlus.style.backgroundColor = "#ff9f0a";
        operatorPlus.style.color = "white";
    
        operatorMinus.style.backgroundColor = "#ff9f0a";
        operatorMinus.style.color = "white";
    
        operatorMultiplication.style.backgroundColor = "#ff9f0a";
        operatorMultiplication.style.color = "white";
    
        operatorDivision.style.backgroundColor = "#ff9f0a";
        operatorDivision.style.color = "white";

    }

    if(!fresh){
        if(input == '+'){
            operatorPlus.style.backgroundColor = "white";
            operatorPlus.style.color = "#ff9f0a";
        }else if(input == '-'){
            operatorMinus.style.backgroundColor = "white";
            operatorMinus.style.color = "#ff9f0a";
        }else if(input == '*'){
            operatorMultiplication.style.backgroundColor = "white";
            operatorMultiplication.style.color = "#ff9f0a";
        }else if(input == '/'){
            operatorDivision.style.backgroundColor = "white";
            operatorDivision.style.color = "#ff9f0a";
        }
    }
    if(displayMem != null && !operatorSelected && !equalsPerformed){
        if(operator == '+'){
            display.value = Number(displayMem) + Number(display.value);
        }else if(operator == '-'){
            display.value = Number(displayMem) - Number(display.value);
        }else if(operator == '*'){
            display.value = Number(displayMem) * Number(display.value);
        }else if(operator == '/'){
            display.value = Number(displayMem) / Number(display.value);
        }
    }
    
    equalsPerformed = false;
    
    if(display.value != ""){
        operator = input;
        operatorSelected = true;
    }    

}

function getPercentage(){

    if(display.value != ""){
    display.value = Number(display.value)/100;
    equalsPerformed = false;
    }
}

function clearDisplay(){

    
    operatorPlus.style.backgroundColor = "#ff9f0a";
    operatorPlus.style.color = "white";
    
    operatorMinus.style.backgroundColor = "#ff9f0a";
    operatorMinus.style.color = "white";
    
    operatorMultiplication.style.backgroundColor = "#ff9f0a";
    operatorMultiplication.style.color = "white";
    
    operatorDivision.style.backgroundColor = "#ff9f0a";
    operatorDivision.style.color = "white";
    
    
    operatorSelected = false;
    operator = "";
    display.value = "";
    displayMem = "";
    equalsPerformed = false;
    fresh = true;


}

function changeKeySignature(){

    if(display.value != ""){
    display.value = -1 * Number(display.value);
    equalsPerformed = false;
    }

}

function calculate(){

    if(displayMem != null && !operatorSelected){
        if(operator == '+'){
            display.value = Number(displayMem) + Number(display.value);
        }else if(operator == '-'){
            display.value = Number(displayMem) - Number(display.value);
        }else if(operator == '*'){
            display.value = Number(displayMem) * Number(display.value);
        }else if(operator == '/'){
            display.value = Number(displayMem) / Number(display.value);
        }
    }

    operatorSelected = false;
    equalsPerformed = true;

}