taskman_version/version.inc.php

<?php
namespace taskman;
use Exception;

task('version', function() 
{
  echo "Version: " . game_version() . "\n";
  echo "Version code:" . game_version_code() . "\n";
});

task('inc_game_version', function()
{     
  $path_to_version = get_path_to_version_file();
  ensure_write($path_to_version, get_inc_game_version());    
  git_try_commit($path_to_version, "inc version");      
});     

function game_version_full_str()
{
  return trim(file(get_path_to_version_file())[0]);
}

function game_version()
{
  $full_str = game_version_full_str();
  $has_patch_code = substr_count($full_str, '.') > 2;
  if(!$has_patch_code)
    return $full_str;
  return substr($full_str, 0, strrpos($full_str, '.'));
}

function game_version_code($str = null)
{
  $str = $str === null ? game_version() : $str;
  $items = explode('.', $str);
  if(sizeof($items) < 2)
    throw new Exception("Bad version format: $str");

  $maj = $items[0];
  $min = $items[1];
  $pat = isset($items[2]) ? $items[2] : 0;

  $num = $pat + $min*100 + $maj*1000000;
  return $num;
}

function game_patch_code()
{
  $full_str = game_version_full_str();
  $has_patch_code = substr_count($full_str, '.') > 2;
  if(!$has_patch_code)
    return 0;

  $code = substr($full_str, strrpos($full_str, '.')+1);
  if($code > 9)
    throw new Exception("Patch code must be <= 9");
  return $code;
}

function get_path_to_version_file()
{
  global $GAME_ROOT;
  return $GAME_ROOT . '/' . getor('VERSION_FILE_NAME', "VERSION");
}

function get_inc_game_version()     
{     
  $string = game_version();     

  for($i = strlen($string) - 1; $i >= 0; $i--)       
  {     
    if(is_numeric($string[$i]))      
    {     
      $most_significant_number = $i;      
      if($string[$i] < 9)      
      {     
        $string[$i] = $string[$i] + 1;      
        break;      
      }     
      // The number was a 9, set it to zero and continue.     
      $string[$i] = 0;      
    }     
  }     

  // If the most significant number was set to a zero it has overflowed so we     
  // need to prefix it with a '1'.      
  if($string[$most_significant_number] === '0')      
    $string = substr_replace($string, '1', $most_significant_number, 0);      

  return $string;     
}

function get_version_file_lifetime()
{
  exec("git log --follow --format=%ad --date=format:\"%Y-%m-%d %H:%M:%S\" " . get_path_to_version_file() , $out, $ret);
  if($ret != 0)
    throw new Exception("git error");
  $minutes = (time() - strtotime($out[0])) / 60;
 
  return ceil($minutes);
}