03.Vacation

class Vacation {
    constructor(organizer, destination, budget) {
        this.organizer = organizer;
        this.destination = destination;
        this.budget = budget;
        this.kids = {};
    }

    get numberOfChildren() {
        //problem description changed during exam - new return value;
        let sumChildren = 0;
        //let empty = `No children are enrolled for the trip and the organization of ${this.organizer} falls out...`

        Object.values(this.kids).forEach( gr => {sumChildren += gr.length});

        //return sumChildren > 0 ? sumChildren : empty;
        return sumChildren;
    }

    registerChild(name, grade, budget){
        let kid = `${name}-${budget}`;
        if(budget < this.budget) {
            return `${name}\'s money is not enough to go on vacation to ${this.destination}.`;
        } else {
            if(this.kids.hasOwnProperty(grade)) {
                if(this.kids[grade].includes(kid)) {
                    return `${name} is already in the list for this ${this.destination} vacation.`
                } else {
                    this.kids[grade].push(kid);
                    return this.kids[grade];
                }
            } else {
                this.kids[grade] = [];
                this.kids[grade].push(kid);
                return this.kids[grade];
            }
        }
    }

    removeChild(name, grade) {
        if(this.kids.hasOwnProperty(grade)) {
            let gradeToSearch = this.kids[grade];

            for (let i = 0; i < gradeToSearch.length; i++) {
                if(gradeToSearch[i].startsWith(name)) {
                    gradeToSearch.splice(i, 1);
                    return gradeToSearch;
                }
            }
        }
        return `We couldn\'t find ${name} in ${grade} grade.`
    }

    toString() {
        let output = '';
        output += `No children are enrolled for the trip and the organization of ${this.organizer} falls out...`;

        if(this.numberOfChildren > 1) {
            output = `${this.organizer} will take ${this.numberOfChildren} children on trip to ${this.destination}\n`

            for (const gr of Object.keys(this.kids)) {
                output += `Grade: ${gr}\n`;
                let count = 1;
                for (const kid of this.kids[gr]) {
                    output += `${count++}. ${kid}\n`;
                }
            // output += '\n'
            //- incorrect problem description, judge zero tests failed;
            }
        }
        return output;
    }
}