const people = ["Alice", "Bob", "Carly", "Dan", "Ed", "Ferdinand", "Ginny"]

function generateSecretSantaPairs(arr) {
    // let pairs = {};
    // let copy = [...arr]; 

    // for(let i = 0; i < arr.length; i++) {
    //     let person = arr[i];
    //     let index;
    //     if(copy.length === 1) {
    //         pairs[person] = copy[0];
    //         pairs[copy[0]] = person;
    //         break;
    //     }

    //     do {
    //         index = Math.floor(Math.random() * copy.length);
    //     } while(copy[index] === person && copy.length > 1)

    //     pairs[person] = copy[index];
    //     copy.splice(index, 1);
    // }
    // console.log(pairs)
    // return pairs;
    
    let pairs = {};
    let copy = [...arr]; 

    for(let i = 0; i < arr.length; i++) {
        let person = arr[i];
        let index;
        if(copy.length === 1) {
            pairs[person] = copy[0];
            pairs[copy[0]] = person;
            break;
        }

        do {
            index = Math.floor(Math.random() * copy.length);
        } while(copy[index] === person || Object.values(pairs).includes(copy[index]) && copy.length > 1)

        pairs[person] = copy[index];
        copy.splice(index, 1);
    }
    console.log(pairs)
    return pairs;   
}

generateSecretSantaPairs(people);

/**
Example output:
{
    Alice: "Dan",
    Bob: "Ferdinand",
    Carly: "Ed",
    Dan: "Alice",
    Ed: "Ginny",
    Ferdinand: "Bob",
    Ginny: "Carly"
}
 */