<?php

define('DRUPAL_ROOT', getcwd());

$_SERVER['REMOTE_ADDR'] = '127.0.0.1';
error_reporting(E_ALL | E_STRICT);

require_once DRUPAL_ROOT . '/core/includes/bootstrap.inc';
// DRUPAL_BOOTSTRAP_PAGE_CACHE calls into config() already.
drupal_bootstrap(DRUPAL_BOOTSTRAP_CONFIGURATION);
require_once DRUPAL_ROOT . '/core/includes/file.inc';
require_once DRUPAL_ROOT . '/core/includes/common.inc';

// Note: Not required for new version, but loaded in both cases for equality.
require_once DRUPAL_ROOT . '/core/includes/database.inc';

//$loader = drupal_classloader();
//$loader->registerNamespace('Symfony\Component\Finder', dirname(__DIR__) . '\symfony\src');

function no_op($text) {
  return $text;
}

function format_kb($size, $previous_size = NULL) {
  $out = '';
  if (isset($previous_size)) {
    $size = $size - $previous_size;
    $out = ($size > 0 ? '+' : '');
  }
  $out .= number_format($size / 1024, 2) . ' KB';
  return $out;
}

/**
 * Initialization.
 */
if (file_exists(DRUPAL_ROOT . '/.git/HEAD')) {
  readfile(DRUPAL_ROOT . '/.git/HEAD');
}

const ITERATIONS = 10;
$data = 'text is the argument';

// Default initialization.
$memory_peak_init = memory_get_peak_usage();
echo 'Peak memory before test: ' . format_kb($memory_peak_init) . PHP_EOL;
echo 'Iterations: ' . ITERATIONS . PHP_EOL;
echo PHP_EOL;

$start = microtime(true);
for ($i=0; $i < ITERATIONS; ++$i) {
}
$stop = microtime(true);
echo 'nothing: ' . round($stop - $start, 4) . ' seconds' . PHP_EOL;

$start = microtime(true);
for ($i=0; $i < ITERATIONS; ++$i) {
  $text = no_op($data);
}
$stop = microtime(true);
echo 'function no_op(): ' . round($stop - $start, 4) . ' seconds' . PHP_EOL;

/**
 * Test cases.
 */

$dir = 'core/modules';
$mask = '/^' . DRUPAL_PHP_FUNCTION_PATTERN . '\.module$/';

$start = microtime(true);
for ($i=0; $i < ITERATIONS; ++$i) {
    $files_to_add = file_scan_directory($dir, $mask, array(
      'key' => 'name',
      'min_depth' => 1,
      // Do not recurse into ./lib directories; they cannot contain extensions.
      // We also skip templates, css, and js directories.
      // @todo Find a way to skip ./config directories (but not modules/config).
      'nomask' => '/^(CVS|lib|templates|css|js)$/',
    ));
}
$stop = microtime(true);
echo 'drupal_system_listing()' . ': ' . round($stop - $start, 4) . ' seconds' . PHP_EOL;

$skip_dirs = array('config', 'lib', 'templates', 'js', 'css');
$skip_dirs = array_combine($skip_dirs, $skip_dirs);

$start = microtime(true);
for ($i=0; $i < ITERATIONS; ++$i) {
  $flags = FilesystemIterator::UNIX_PATHS | FilesystemIterator::SKIP_DOTS;
  $flags |= FilesystemIterator::CURRENT_AS_SELF;
  $flags |= FilesystemIterator::KEY_AS_FILENAME;

  $directory = new RecursiveDirectoryIterator($dir, $flags);
  $filter = new SystemListRecursiveFilterIterator($directory, $mask, $skip_dirs);
  $iterator = new RecursiveIteratorIterator($filter);
  $files = array();
  foreach ($iterator as $filename => $file) {
    $file->uri = $file->getPathName();
    $file->filename = $file->getFileName();
    $file->name = pathinfo($file->filename, PATHINFO_FILENAME);
    $files[$file->name] = $file;
  }
}
$stop = microtime(true);
echo 'SystemListRecursiveFilterIterator' . ': ' . round($stop - $start, 4) . ' seconds' . PHP_EOL;


/*
$start = microtime(true);
for ($i=0; $i < ITERATIONS; ++$i) {
  $extension = 'module';
  $finder = new Symfony\Component\Finder\Finder();
  $finder
    ->files()
    ->depth('> 1')
    ->name($mask)
    ->exclude(array('lib', 'templates', 'js', 'css', 'config'))
    ->in('core/modules');
  
  $files = array();
  foreach ($finder as $file) {
    $file->uri = $file->getPathName();
    $file->filename = $file->getFileName();
    $file->name = pathinfo($file->filename, PATHINFO_FILENAME);
    $files[$file->name] = $file;
  }
}
$stop = microtime(true);
echo 'Finder' . ': ' . round($stop - $start, 4) . ' seconds' . PHP_EOL;
*/

# This is what Finder is doing under the hood:

/*
$mask = '/\/' . DRUPAL_PHP_FUNCTION_PATTERN . '\.module$/';

$start = microtime(true);
for ($i=0; $i < ITERATIONS; ++$i) {
  $flags = FilesystemIterator::UNIX_PATHS | FilesystemIterator::SKIP_DOTS;
  $flags |= FilesystemIterator::CURRENT_AS_FILEINFO;
  
  $flags |= FilesystemIterator::KEY_AS_FILENAME;
  
  $results = new RecursiveDirectoryIterator($dir, $flags);
  $flattened = new RecursiveIteratorIterator($results);
  $filtered = new RegexIterator($flattened, $mask);
  $files = array();
  foreach ($filtered as $filename => $file) {
    $file->uri = $file->getPathName();
    $file->filename = $file->getFileName();
    $file->name = pathinfo($file->filename, PATHINFO_FILENAME);
    $files[$file->name] = $file;
  }
}
$stop = microtime(true);
echo 'DirectoryIterator' . ': ' . round($stop - $start, 4) . ' seconds' . PHP_EOL;
*/

/**
 * Tear down.
 */
echo PHP_EOL;

$memory_peak_end = memory_get_peak_usage();
echo 'Peak memory after test: ' . format_kb($memory_peak_end) . PHP_EOL;
echo 'Memory difference: ' . format_kb($memory_peak_end, $memory_peak_init) . PHP_EOL;


class SystemListRecursiveFilterIterator extends RecursiveFilterIterator {
  protected $regex;
  protected $hasExtension;
  protected $skipExtensionDirs;

  public function __construct(RecursiveIterator $iterator, $regex, array $skip_dirs, $has_extension = FALSE) {
    $this->hasExtension = $has_extension;
    $this->regex = $regex;
    $this->skipExtensionDirs = $skip_dirs;
    parent::__construct($iterator);
  }

  public function getChildren() {
    return new self($this->getInnerIterator()->getChildren(), $this->regex, $this->skipExtensionDirs, $this->hasExtension);
  }

  public function accept() {
    if ($this->isDir()) {
      if (!$this->hasExtension) {
        return TRUE;
      }
      // If the directory name does not appear in the names to skip, accept it.
      return !isset($this->skipExtensionDirs[$this->current()->getFilename()]);
    }
    else {
      $is_extension = preg_match($this->regex, $this->current()->getFilename());
      if ($is_extension) {
        $this->hasExtension = TRUE;
      }
      return $is_extension;
    }
  }
}