// Capitalise keys

function capitaliseKeys(obj) {
    let newObj;
    let entries = Object.entries(obj);
    let mapEntries = entries.map((keyValue) => [
        keyValue[0].toUpperCase(), keyValue[1]
    ]);
    newObj = Object.fromEntries(mapEntries); 
    return newObj; 
}

console.log(capitaliseKeys({ a: 1, b: 2, c: 3 }));
console.log(capitaliseKeys({ Hello: "hi" }));
console.log(capitaliseKeys({}));
        

// String to object

function stringToObject(str) {
    let obj = {};
    if (str.length === 0) {
        return obj;
    }
    else {
        let splitStr = str.split(",");
        for (let i = 0; i < splitStr.length; i++) {
            let parts = splitStr[i].split(':');
            obj[parts[0]] = parts[1];
        }
        return obj;
    }
}
        
console.log(stringToObject(""));
console.log(stringToObject("a:1,b:2,c:3"));
console.log(stringToObject("one:-1,two:hi there,three:what's that?"))
        

// Going shopping

function shoppingList(str) {
    let obj = {};
    if (str.length === 0) {
        return obj;
    }
    else {
        let splitStr = str.split(",")
        for (let i = 0; i < splitStr.length; i++) {
            let parts = splitStr[i].split(" ").reverse();
            if (parts[1] == 0) {
                splitStr.pop(splitStr[i]);
            }
            else {
                obj[parts[0]] = Number(parts[1]);
            }
        } 
        return obj;
    }
}
        
console.log(shoppingList("2 tomatoes, 1 egg, 3 pumpkins"));
console.log(shoppingList(""));
console.log(shoppingList("2 tomatoes, 1 egg, 0 pumpkins"));
        

// Map Object

function mapObject(obj, fn) {
    let newObj;
    let entries = Object.entries(obj);
    let mapEntries = entries.map((keyValue) => 
        [keyValue[0], fn(keyValue[1])]
        );
    newObj = Object.fromEntries(mapEntries);
    return newObj;
    }   
    
console.log(mapObject({ a: 1, b: 2 }, (n) => n + 2));
console.log(mapObject(
    { greeting: 'hi there, ', goodbye: 'see you later, ' }, 
    (s) => s + 'Yvonne'));