How to implement an array grouping algorithm by value?

Question

PHP

There is an array with days of the week and hours of work

$openingHours = [
            ['day' => 'monday', 'time' => '08:00-20:00'],
            ['day' => 'tuesday', 'time' => '08:00-20:00'],
            ['day' => 'wednesday', 'time' => '08:00-20:00'],
            ['day' => 'thursday', 'time' => '10:00-20:00'],
            ['day' => 'friday', 'time' => '10:00-18:00'],
            ['day' => 'saturday', 'time' => '10:00-16:00'],
            ['day' => 'sunday', 'time' => '10:00-16:00'],
        ];

It is necessary to group it so that days with the same working hours are combined into one element. More or less like this

$result = [
            'monday - wednesday' => '08:00-20:00',
            'thursday' => '10:00-20:00',
            'friday' => '10:00-18:00',
            'saturday - sunday' => '10:00-16:00',
        ];

How can this be achieved? Thank you!

Answer 1

Assuming the days of the week are in ascending order, you could use something like this:

$openingHours = [
    ['day' => 'monday', 'time' => '08:00-20:00'],
    ['day' => 'tuesday', 'time' => '08:00-20:00'],
    ['day' => 'wednesday', 'time' => '08:00-23:59'],
    ['day' => 'thursday', 'time' => '08:00-20:00'],
    ['day' => 'friday', 'time' => '08:00-20:00'],
    ['day' => 'saturday', 'time' => '10:00-16:00'],
    ['day' => 'sunday', 'time' => '10:00-16:00'],
];

$result = $active = [];

$openingHours[] = ['day' => '', 'time' => '']; // empty value to simplify code

foreach ($openingHours as $openingHour) {
    if ($active) {
        if ($active['time'] === $openingHour['time']) {
            $active['end'] = $openingHour['day'];
        } else {
            $key          = $active['end'] ? $active['start'] . '-' . $active['end'] : $active['start'];
            $result[$key] = $active['time'];
            $active       = [];
        }
    }
    $active = $active ?: [
        'time'  => $openingHour['time'],
        'start' => $openingHour['day'],
        'end'   => null,
    ];
}

print_r($result);

Answer 2

Head-on solution: create an associative array, where the key is time, the value is an array of days of the week. And just go through each element of $openingHours, take time from it, check if it is in our created array, if not, create and add a day there, if there is, then just add a day there.
Well, then write a function that will transform our created array into the one you need. This is also quite simple, we look at the key, take its values, connect them through the separator -, and use it as a key in a new array.

Answer 3

If, according to the plan, Vladimir Proskurin

$openingHours = [
            ['day' => 'monday', 'time' => '08:00-20:00'],
            ['day' => 'tuesday', 'time' => '08:00-20:00'],
            ['day' => 'wednesday', 'time' => '08:00-20:00'],
            ['day' => 'thursday', 'time' => '10:00-20:00'],
            ['day' => 'friday', 'time' => '10:00-18:00'],
            ['day' => 'saturday', 'time' => '10:00-16:00'],
            ['day' => 'sunday', 'time' => '10:00-16:00'],
        ];
$temp = array();
$result = array();

foreach($openingHours as $key => $item) {
  $temp[$item['time']][] = $item['day']; 
}
foreach($temp as $key => $item){
  $count = count($item) -1;
  $count >= 1 ? $result[$item[0].'-'.$item[$count]] = $key : $result[$item[0]] = $key; 
}
print_r($result);

Array
(
    [monday-wednesday] => 08:00-20:00
    [thursday] => 10:00-20:00
    [friday] => 10:00-18:00
    [saturday-sunday] => 10:00-16:00
)

PS I'll be happy to look at other implementations or simplifications of the above

Answer 4

The result is an array with the days of the week in an ordered form. It remains only to come up with a function that will determine that the days go in a row without a break and put a "dash", otherwise a comma. I wrote it on the phone))) When I get to the computer, I’ll think it over

$openingHours = [
            ['day' => 'tuesday', 'time' => '08:00-20:00'],
            ['day' => 'wednesday', 'time' => '08:00-20:00'],
            ['day' => 'thursday', 'time' => '10:00-20:00'],
            ['day' => 'friday', 'time' => '10:00-18:00'],
            ['day' => 'saturday', 'time' => '10:00-16:00'],
            ['day' => 'sunday', 'time' => '10:00-16:00'],
            ['day' => 'monday', 'time' => '08:00-20:00'],
        ];
$template = ['sunday','monday','tuesday','wednesday','thursday','friday','saturday'];
$new = array();
foreach ($openingHours as $key => $value){
  $new[$value['time']][] = $value['day'];
  $new[$value['time']] = array_intersect($template,$new[$value['time']]);
}
print_r($new);

Array
(
    [08:00-20:00] => Array
        (
            [1] => monday
            [2] => tuesday
            [3] => wednesday
        )

    [10:00-20:00] => Array
        (
            [4] => thursday
        )

    [10:00-18:00] => Array
        (
            [5] => friday
        )

    [10:00-16:00] => Array
        (
            [0] => sunday
            [6] => saturday
        )
)

Well, the keys are saved for the names of the days, you can add keys from 1 to 7 in the sorting template, so that in the future, if necessary, get the day of the week by the key (the ordinal number of the day in the week)