将JIRA时间日志#h #m #s格式的持续时间转换为00:00:00

I want to convert my time duration from 1h 20m 53s into 01:20:53 format. My time duration may only have 20m 53s or 25m or 1h or 23s. I need to convert that into time format of 00:00:00.

You can use a regex of ^(?:(?<hours>\d+)h\s*)?(?:(?<minutes>\d+)m\s*)?(?:(?<seconds>\d+)s\s*)?$ and sprintf to make sure that zeroes are prepended:

<?php

function translateTime($timeString) {
    if (preg_match('/^(?:(?<hours>\d+)h\s*)?(?:(?<minutes>\d+)m\s*)?(?:(?<seconds>\d+)s\s*)?$/', $timeString, $matches)) {
        return sprintf(
            '%02s:%02s:%02s',
            (!empty($matches['hours'])   ? $matches['hours']   : '00'),
            (!empty($matches['minutes']) ? $matches['minutes'] : '00'),
            (!empty($matches['seconds']) ? $matches['seconds'] : '00')
        );
    }

    return '00:00:00';
}

var_dump( translateTime('1h 20m 53s') ); //string(8) "01:20:53"
var_dump( translateTime('20m 53s') );    //string(8) "00:20:53"
var_dump( translateTime('53s') );        //string(8) "00:00:53"
var_dump( translateTime('1h 30s') );     //string(8) "01:00:30"
var_dump( translateTime('2h 3m') );      //string(8) "02:03:00"

DEMO

While looking scary the regex is just a bunch of named capture groups:

\s is a white space character (space, tab, , , \f)
\d is a digit (0, 1, 2, 3, 4, 5, 6, 7, 8, 9)

first make the string compatible with php DateTime object

$time = preg_split( "/(h|m|s)/i", " 1H 20m 53s " , null, PREG_SPLIT_DELIM_CAPTURE);

$h = 0;
$m = 0;
$s = 0;

$count = count($time);

if ($count == 7)
{
    ${strtolower($time[1])} = $time[0];
    ${strtolower($time[3])} = $time[2];
    ${strtolower($time[5])} = $time[4];
}
else if ($count == 5)
{
    ${strtolower($time[1])} = $time[0];
    ${strtolower($time[3])} = $time[2];
}
else if ($count == 3)
{
    ${strtolower($time[1])} = $time[0];
}

$date = new \DateTime();
$date->setTime($h, $m, $s);
echo $date->format('H:i:s');

you can now post it in any format php DateTime supports