PHP get next day name in array if current day name is not exists-CodePudding

Please help me, I have $repeatdays array $repeatdays = ['sunday', 'monday', 'tuesday', 'wednesday', 'thursday', 'friday', 'saturday'],

I do this to get next day name:

$current = 'wednesday';
$keys = array_values($repeatdays);
$ordinal = (array_search($current,$keys) 1)%count($keys);
$nextreccurence = strtolower($keys[$ordinal]);
echo $nextreccurence; // will return 'thursday'

but what if 'wednesday' is not exist in $repeatdays? for example $repeatdays = ['sunday', 'monday', 'tuesday', 'thursday', 'friday', 'saturday'] I do this again:

$current = 'wednesday';
$keys = array_values($repeatdays);
$ordinal = (array_search($current,$keys) 1)%count($keys);
$nextreccurence = strtolower($keys[$ordinal]);
echo $nextreccurence; // but now only return 'monday', my expected result 'thursday'

how I can get expected 'thursday' result if 'wednesday' is not exist in that array?

====
by the way, $repeatdays is dynamic by user selected day that stored into $repeatdays. for example if today is 'wednesday' then user selected is ['sunday', 'friday'], then I want system to get 'friday',

AND if today is 'friday' then user selected is ['sunday', 'friday'], then I want system to get 'sunday',

CodePudding user response：

If you can use the php functions, then you can do this:

$dayoftheweek = "wednesday"; // or however you populate it
$timestampday = strtotime($dayoftheweek);

echo date('l', strtotime(" 1 day", $timestampday));

CodePudding user response：

One solution would be to have a second, reference array with all the days, where you could look up next days until you'll find one that is available also in $repeatdays.

One not perfect implementation would be:

<?php

function get_next_day($current)
{
    $reference = ['sunday', 'monday', 'tuesday', 'wednesday', 'thursday', 'friday', 'saturday'];
    $current_key = array_search($current, $reference);
    $next_key = ($current_key   1) % count($reference);
    return $reference[$next_key];
}

function search_for_available_next_day($current, $repeatdays)
{
    $next = $current;
    do {
        $next = get_next_day($next);
    }
    while (!in_array($next, $repeatdays));
    return $next;
}

var_dump(search_for_available_next_day('wednesday', ['sunday', 'friday']));
var_dump(search_for_available_next_day('friday', ['sunday', 'friday']));
var_dump(search_for_available_next_day('thursday', ['sunday', 'friday']));
var_dump(search_for_available_next_day('saturday', ['sunday', 'friday']));