abu sofian challenge

index.php

<?php
require '../vendor/autoload.php';

use Carbon\Carbon;

const DATE_FORMAT = 'd/m/Y';
const TIME_FORMAT = 'H:i:s';

Carbon::setWeekStartsAt(Carbon::SATURDAY);

$user = [
    "workHours" => [
        ["from" => "08:00:00", "to" => "16:00:00"],
        ["from" => "08:00:00", "to" => "16:00:00"],

        ["from" => "08:00:00", "to" => "16:00:00"],
        ["from" => "08:00:00", "to" => "16:00:00"],

        ["from" => "08:00:00", "to" => "16:00:00"],
        ["from" => "08:00:00", "to" => "16:00:00"],
        ["from" => "08:00:00", "to" => "16:00:00"],
        ["from" => "08:00:00", "to" => "16:00:00"],

        ["from" => "08:00:00", "to" => "16:00:00"],
    ],
    "sessions" => [
        [
            "date" => "17/6/2017", "status" => "approved",
            "from" => "09:00:00", "end" => "11:00:00",
        ],
        [
            "date" => "17/6/2017", "status" => "new",
            "from" => "12:00:00", "end" => "02:00:00",
        ],
    ],
];


function freeAt($user, $newSession)
{
    //the wrapping  should be done in data postprocessing and not within the function
    //wrap work hours times into carbon objects
    $user['workHours'] = collect($user['workHours'])->map(function ($item) {
        $item['from'] = Carbon::createFromFormat(TIME_FORMAT, ($item['from']));
        $item['to'] = Carbon::createFromFormat(TIME_FORMAT, ($item['to']));
        return $item;
    });
    //wrap sessions date and times into carbon objects
    $user['sessions'] = collect($user['sessions'])->map(function ($item) {
        return [
            'date' => Carbon::createFromFormat(DATE_FORMAT, ($item['date'])),
            'from' => Carbon::createFromFormat(TIME_FORMAT, ($item['from'])),
            'end' => Carbon::createFromFormat(TIME_FORMAT, ($item['end'])),
            'status' => $item['status']
        ];
    });
    //wrap newSession date and times into carbon objects
    $newSession['date'] = Carbon::createFromFormat(DATE_FORMAT, ($newSession['date']));
    $newSession['from'] = Carbon::createFromFormat(TIME_FORMAT, ($newSession['from']));
    $newSession['end'] = Carbon::createFromFormat(TIME_FORMAT, ($newSession['end']));

    //saturday index is 6 , monday is 0  , map workHours array to 7 days of week
    $index = ($newSession['date']->dayOfWeek) % 6;


    $withinWorkHrs = !empty($user['workHours'][$index]) && // week day has working hours
        // check if the proposed date is within the working hours of that day
        ($newSession['from']->between(
                $user['workHours'][$index]['from']->subMinutes(30),
                $user['workHours'][$index]['to']->addMinutes(30))
            &&
            $newSession['end']->between(
                $user['workHours'][$index]['from']->subMinutes(30),
                $user['workHours'][$index]['to']->addMinutes(30)
            ));


    if (!$withinWorkHrs) return false; // chosen day doesn't have working hours


    return collect($user['sessions'])
        ->where('date', $newSession['date'])
        ->where('status', 'approved')
        ->pipe(function ($result) use ($newSession) {
            //if proposed day isn't in approved sessions , then that appointment is free
            return $result->isEmpty() ? true :
                //check each session for intersections in time intervals
                $result->filter(function ($item) use ($newSession) {

                    return
                        !($newSession['from']->between(
                            $item['from']->subMinutes(30),
                            $item['end']->addMinutes(30)))
                        &&
                        !($newSession['end']->between(
                            $item['from']->subMinutes(30),
                            $item['end']->addMinutes(30)
                        ));
                });
        })->isEmpty();
}

var_dump(freeAt($user, [
    "date" => "17/6/2017", "status" => "new",
    "from" => "10:30:00", "end" => "11:00:00",
]));