Extract data from a multidimensional array where a given date string in found in the delimited string of a deep subarray

Question

I have this array containing my bookings:

$bookings[] = array(
    'booking_id' => '1', 
    'client_firstname' => 'Gareth', 
    'days' => array(
        array('day_id' => '2016-11-23,2016-11-24', 'room_id' => '2'),
        array('day_id' => '2016-11-25', 'room_id' => '4'),
        array('day_id' => '2016-11-26,2016-11-27,2016-11-28', 'room_id' => '2'),
    )
);
$bookings[] = array(
    'booking_id' => '2', 
    'client_firstname' => 'James', 
    'days' => array(
        array('day_id' => '2016-11-25,2016-11-26,2016-11-27,2016-11-28', 'room_id' => '5')
    )
);
$bookings[] = array(
    'booking_id' => '2', 
    'client_firstname' => 'Marco', 
    'days' => array(
        array('day_id' => '2016-11-24', 'room_id' => '5')
    )
);

---

Explication of the array:

- The array shows the `booking_id` and the `client_name`. - The array `days` contains the schedule of the client in the hotel. Each array in this `days` array explains which days and in which room the client is. If I have more than one line, the client change room.

---

The wish

For a date I give, I need to get the bookings where into the `days array` the first date correspond to the date I give.

---

Example

- Date I give is `2016-11-25`. - I need to get:

`$bookings[] = array(
    'booking_id' => '1', 
    'client_firstname' => 'Gareth', 
    'days' => array(
        array('day_id' => '2016-11-25', 'room_id' => '4')
    )
);
$bookings[] = array(
    'booking_id' => '2', 
    'client_firstname' => 'James', 
    'days' => array(
        array('day_id' => '2016-11-25,2016-11-26,2016-11-27,2016-11-28', 'room_id' => '5')
    )
);`

---

What I have try

$day_value = '2016-11-23';
$bookings_ = array();
foreach($bookings as $b){
    foreach($b['days'] as $day){
       if(in_array($day_value,explode(',',$day['day_id'][0]))){
         $bookings_[]  = $b;
       }
    }
}
print_r($bookings_); 

But it returns me all the results into the bookings.

Answer 1

What do you think is $day['day_id'][0]?

It's the first symbol of $day['day_id'] as latter is a string. So, nothing will be exploded by , in $day['day_id'][0]. And solution is to remove [0]:

foreach($bookings as $b){
    foreach($b['days'] as $day){
        if(in_array($day_value,explode(',',$day['day_id']))){
            // this string added:
            $b['days'] = $day;

            $bookings_[]  = $b;

            // btw, if your `$b['days']` has several elements
            // and in a couple of them there's a required date
            // then `$b` will be added to `$bookings_` several 
            // times, so probably you need `break`
            // break;
        }
    }
}