PHP Code to write JSON file

JsonHelper.php

<?php
public function writeJsonFile($jsonFileNamePath, $jsonData)
{
    if (file_exists($jsonFileNamePath) ) {
        preg_match('/^\[(.+)\]$/', $jsonData, $removeBracket);
        $jsonFileHandle = fopen($jsonFileNamePath, 'c');
        // move back a byte
        fseek($jsonFileHandle, -1, SEEK_END);

        $pointerPosition = ftell($jsonFileHandle);
        if ($pointerPosition > 0) {
            // add the new json string
            fwrite($jsonFileHandle, ',' . $removeBracket[1] . ']');
        } else {
            fwrite($jsonFileHandle, $jsonData);
        }
    } else {
        $jsonFileHandle = fopen($jsonFileNamePath, 'w');
        // write the first string
        fwrite($jsonFileHandle, $jsonData);
    }
    fclose($jsonFileHandle);
}