So I managed to create my own function in the end. Thanks for help and inspiration though.
function replaceWithCase($source, $replacement, $string, $pos = 0) {
while (($pos = strpos(strtolower($string), strtolower($source), $pos))!== false) {
$substr = mb_substr($string, $pos, strlen($source));
$remaining = mb_substr($string, $pos + strlen($source));
if (ctype_upper($substr)) {
$string = substr_replace($string,strtoupper($replacement),$pos,strlen($source));
continue;
}
$substrParts = preg_split('//u', $substr, null, PREG_SPLIT_NO_EMPTY);
$replaceParts = preg_split('//u', $replacement, null, PREG_SPLIT_NO_EMPTY);
$newWord = '';
foreach ($replaceParts as $k => $rp) {
if (array_key_exists($k,$substrParts))
$newWord .= ctype_upper($substrParts[$k]) ? mb_strtoupper($rp) : mb_strtolower($rp);
else
$newWord .= $rp;
}
$string = substr_replace($string,$newWord,$pos,strlen($source));
$pos = $pos + strlen($source);
}
return $string;
}
echo replaceWithCase("place", "garden", "Potato is jumping all over the PLACE");
echo "<br>";
echo replaceWithCase("jumping", "running", "Potato is jumping all over the pLAcE");
echo "<br>";
echo replaceWithCase("jumping", "cry", "Potato is jumping all over the place");
echo "<br>";
echo replaceWithCase("all", "", "Potato is jumping all over the Place");
echo "<br>";
echo replaceWithCase(" ", ";", "Potato is jumping all over the Place", 10);
echo "<br>";
Output:
Potato is jumping all over the GARDEN
Potato is running all over the pLAcE
Potato is cry all over the place
Potato is jumping over the Place
Potato is jumping;all;over;the;Place