src/string-functions.php ➔ vnsprintf()

Complexity

Conditions	5
Paths	5

Size

Total Lines	52
Code Lines	22

Duplication

Lines	0
Ratio	0 %

Importance

Changes	1
Bugs	0	Features	1

<?php
function vnsprintf($format, $args)
{
    // we need to find all of the named parameters to expand
    $regex = "|(?<!%)(?:%)([^0-9].+)(?:\\\$)|U";

    $matches = [];
    $matchCount = preg_match_all($regex, $format, $matches, PREG_OFFSET_CAPTURE);
    if ($matchCount === 0) {
        // nothing to do
        return vsprintf($format, $args);
    }

    // if we get here, then we have some matches to expand
    // we're going to add them to the end of this array
    $messageData = $args;

    // this will keep track of where we've added the data
    $nextData = count($messageData);
    $paramKeys = array_fill_keys(array_keys($args), -1);

    // this will keep track of how we've shrunk the format string
    $formatChange = 0;

    // transform the named parameters into offset parameters
    foreach ($matches[1] as $match) {
        // what is the named parameter?
        $paramName = $match[0];

        // make sure the named parameter exists in our original data
        if (!isset($paramKeys[$paramName])) {
            throw new InvalidArgumentException("vnsprintf: named format-string parameter " . $paramName . " is not provided in \$args array");
        }
        // have we already assigned it a place in $messageData?
        // in case a named parameter appears multiple times in the format string
        if ($paramKeys[$paramName] === -1) {
            // no - it needs a home
            $messageData[$nextData] =& $args[$paramName];
            $paramKeys[$paramName] = $nextData;
            $nextData++;
        }
        // convert the named parameter in the format string into a positional
        // parameter into $messageData
        $paramOffset = $paramKeys[$paramName] + 1;
        $format = substr_replace($format, $paramOffset, $formatChange + $match[1], strlen($paramName));

        // how much did we shrink / grow the format string by?
        $formatChange = $formatChange - strlen($paramName) + strlen($paramOffset);
    }

    // all done
    return vsprintf($format, $messageData);
}