class PhpExtensions

class PhpExtensions {
  protected $extensions;
  protected $phpVersion;
  protected $iniPath;
  public function __construct() {
    $this->phpVersion = phpversion();
    $this->iniPath = php_ini_loaded_file();
    $this->extensions = array(
      'memcache' => array(
        'url' => 'http://pecl.php.net/get/memcache-2.2.6.tgz',
        'php_version' => array(),
        'cfg' => array(
          '--enable-memcache',
        ),
        'ini' => array(
          'extension=memcache.so',
        ),
      ),
      'memcached' => array(
        'url' => 'http://pecl.php.net/get/memcached-1.0.2.tgz',
        'php_version' => array(
          // memcached 1.0.2 does not build on PHP 5.4
          array(
            '<',
            '5.4',
          ),
        ),
        'cfg' => array(),
        'ini' => array(
          'extension=memcached.so',
        ),
      ),
      'apc' => array(
        'url' => 'http://pecl.php.net/get/APC-3.1.9.tgz',
        'php_version' => array(
          // apc 3.1.9 causes a segfault on PHP 5.4
          array(
            '<',
            '5.4',
          ),
        ),
        'cfg' => array(),
        'ini' => array(
          'extension=apc.so',
          'apc.enabled=1',
          'apc.enable_cli=1',
        ),
      ),
      'xcache' => array(
        'url' => 'http://xcache.lighttpd.net/pub/Releases/1.2.2/xcache-1.2.2.tar.gz',
        'php_version' => array(
          // xcache does not build with Travis CI (as of 2012-01-09)
          array(
            '<',
            '5',
          ),
        ),
        'cfg' => array(
          '--enable-xcache',
        ),
        'ini' => array(
          'extension=xcache.so',
          'xcache.cacher=false',
          'xcache.admin.enable_auth=0',
          'xcache.var_size=1M',
        ),
      ),
    );
  }
  public function install($name) {
    if (array_key_exists($name, $this->extensions)) {
      $extension = $this->extensions[$name];
      echo "== extension: {$name} ==\n";
      foreach ($extension['php_version'] as $version) {
        if (!version_compare($this->phpVersion, $version[1], $version[0])) {
          printf("=> not installed, requires a PHP version %s %s (%s installed)\n", $version[0], $version[1], $this->phpVersion);
          return;
        }
      }
      $this
        ->system(sprintf("wget %s > /dev/null 2>&1", $extension['url']));
      $file = basename($extension['url']);
      $this
        ->system(sprintf("tar -xzf %s > /dev/null 2>&1", $file));
      $folder = basename($file, ".tgz");
      $folder = basename($folder, ".tar.gz");
      $this
        ->system(sprintf('sh -c "cd %s && phpize && ./configure %s && make && sudo make install" > /dev/null 2>&1', $folder, implode(' ', $extension['cfg'])));
      foreach ($extension['ini'] as $ini) {
        $this
          ->system(sprintf("echo %s >> %s", $ini, $this->iniPath));
      }
      printf("=> installed (%s)\n", $folder);
    }
  }
  private function system($cmd) {
    $ret = 0;
    system($cmd, $ret);
    if (0 !== $ret) {
      printf("=> Command '%s' failed !", $cmd);
      exit($ret);
    }
  }

}