<?php

use Fhaculty\Graph\Uml\ClassDiagramBuilder;
use Fhaculty\Graph\GraphViz;
use Fhaculty\Graph\Graph;
use Symfony\Component\Finder\Finder;
use Drupal\graphapi_class\Plugin\Filter\FilterTrivialGraphFormat;

/**
 * Implements hook_menu().
 */
function graphapi_class_menu() {
  $items['admin/config/system/graphapi/uml'] = array(
    'title' => 'UML Diagrams',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('graphapi_class_form'),
    'route_name' => 'graphapi_class.select',
    'access arguments' => array('access devel information'),
  );
  return $items;
}

function graphapi_class_form($form, &$form_state) {
  $request = drupal_container()->get('request');
  $types = $request->query->get('ids');
  if (empty($types)) {
    $types = array('stdClass');
  }
  $types = array_combine($types, $types);
  ksort($types);
  graphapi_loader();
  $classes = get_declared_classes();
  asort($classes);
  $classes = array_combine($classes, $classes);
  $interfaces = get_declared_interfaces();
  asort($interfaces);
  $interfaces = array_combine($interfaces, $interfaces);
  $kinds = array(
    'services' => _graphapi_class_services(),
    'classes' => $classes,
    'interfaces' => $interfaces,
  );
  $form['class'] = array(
    '#type' => 'select',
    '#title' => 'Select your class or interface',
    '#description' => 'This class will be displayed as part of a Class Diagram.',
    '#options' => $kinds,
    '#required' => TRUE,
    '#multiple' => TRUE,
    '#size' => 20,
    '#default_value' => $types,
  );
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => 'Submit',
  );
  $form['result'] = array(
    '#title' => 'Classes',
    '#prefix' => '<div>',
    '#markup' => graphapi_class_build($types),
    '#suffix' => '</div>',
  );
  return $form;
}

function graphapi_class_form_submit(&$form, &$form_state) {
  $class = $form_state['values']['class'];
  $list = join('+', $class);
  $options = array(
    'absolute' => TRUE,
    'query' => array(
      'ids' => array_keys($class),
    ),
  );
  $url = url('admin/config/system/graphapi/uml', $options);
  $form_state['redirect'] = array(
    $url,
    $options,
  );
  drupal_redirect_form($form_state);
}

/**
 * Generate a hopefully consistent cache id
 *
 * We assume $item when recursive is properly sorted
 *
 * @param array $item
 * @return string
 */
function _graphapi_class_get_cid(array $item) {
  ksort($item);
  $cid = serialize($item);
  $cid = md5($cid);
  return $cid;
}

function _graphapi_class_get_cache($cid) {
  return cache()->get($cid);
}

function _graphapi_class_cache_set($cid, $data) {
  return cache()->set($cid, $data);
}

function _graphapi_class_services() {
  $yaml_discovery = new \Drupal\Component\Discovery\YamlDiscovery('services', \Drupal::moduleHandler()->getModuleDirectories());
  $yaml = $yaml_discovery->findAll();
  $classes = array();
  foreach ($yaml as $module => $services) {
    //dsm($services, $module);
    foreach ($services['services'] as $key => $value) {
      $classes[$value['class']] = "$module:$key";
    }
  }
  //dsm($classes, __FUNCTION__);
  return array_keys($classes);
}

/**
 * Generates a UML CLass Diagram for the given format.
 *
 * @param array $classes
 *   List of class and interface names
 * @param array $config
 *   Settings for both builder as the rendering
 *     generate-script : the dot textual output
 *     generate-image: generate and svg or other image format
 *     only-self : see ClassDiagramBuilder for more info
 *     only-public : see ClassDiagramBuilder
 *     show-constants : see ClassDiagramBuilder
 *     add-parents : see ClassDiagramBuilder
 *
 * @return string
 *   The output is rendered as a group of classes seperated by a HR
 *   TODO: is a HR the best seperation.
 *
 * @see ClassDiagramBuilder
 */
function graphapi_class_build_class(array $classes = array(), array $config = array()) {
  graphapi_loader();

  $config += array(
    'generate-script' => FALSE,
    'generate-image' => TRUE,
//    'type' => 'svg',
  );
  $options = array(
    'script' => $config['generate-script'],
    'render' => $config['generate-image'],
  );
  unset($config['generate-script']);
  unset($config['generate-image']);

//  $cid = _graphapi_class_get_cid($classes, $script_only);
//  if ($o = _graphapi_class_get_cache($cid)) {
//    return $o->data;
//  }
  $result = array();

  $g = new Graph();
  $loader = new ClassDiagramBuilder($g);
  foreach ($config as $option => $value) {
    $loader->setOption($option, $value);
  }
  // Reduce output.
  //$loader->setOption('only-self', TRUE);
  //$loader->setOption('only-public', TRUE);
  //$loader->setOption('show-constants', FALSE);
  $messages[] = array();
  try {
    $i=0;
    foreach ($classes as $class) {
      if ($i++ % 100 == 0) {
        watchdog("graphapi_class", "Progressing to $i items.");
      }
      // Do not try to add an already added class (through reflection)
      if (!$g->hasVertex($class)) {
        try {
          $loader->createVertexClass($class);
        }
        catch (Exception $exc) {
          $message = $exc->getMessage();
          $messages[$class] = $message;
        }
      }
    }
  }
  catch (Exception $exc) {
    return $exc->getMessage();
  }

  $render_options = array(
    'graphapi' => $options,
  );
//    $options = array(
//      'graphapi' => array(
//        'script' => FALSE,
//        'render' => TRUE,
//      )
//    );
  foreach ($loader->createGraphsComponents() as $graph) {
    $result[] = graphapi_render($graph, $render_options);
  }
  $total = join("<hr />", $result);
  //_graphapi_class_cache_set($cid, $total);
  return $total;
}

function graphapi_class_cron() {
  $last_run = _graphapi_class_get_cache(__FUNCTION__);
  // Only generate every hour
  if ($last_run && $last_run->data + 3600 > time()) {
    return;
  }
  _graphapi_class_cache_set(__FUNCTION__, time());
  _graphapi_class_generate_run();
}

function _graphapi_class_generate_run() {
  graphapi_loader();
  $queue = Drupal::queue('graphapi_class_generator');
  $classes = graphapi_class_get_all();
  $count = count($classes);
  $scheduled = 0;
  $options = array(
    'add-parents' => 1,
  );

  foreach ($classes as $path => $class) {
    $item = array(
      'classes' => array($class),
      'path' => $path,
      'options' => $options,
    );

    $cid = _graphapi_class_get_cid($item);
    $cached_item = _graphapi_class_get_cache($cid);
    if ($cached_item === FALSE) {
      $scheduled++;
      $queue->createItem($item);
    }
  }
  watchdog('graphapi_class', 'Scheduled %scheduled out of %count classes and interfaces.', array('%scheduled' => $scheduled, '%count' => $count));
}

/**
 * Implements hook_queue_info().
 */
function graphapi_class_queue_info() {
  $queues['graphapi_class_generator'] = array(
    'title' => t('Generate all UML Graphs'),
    'worker callback' => 'graphapi_class_generator_worker',
    'cron' => array(
      'time' => 60,
    ),
  );
  return $queues;
}

/**
 * Queue worker callback.
 */
function graphapi_class_generator_worker($item) {
  $path_prefix = "graphapi/uml/classdiagrams/";
  if (isset($item['classes'])) {
    $classes = $item['classes'];
  }
  else {
    $classes = array($item['class']);
  }
  $path = 'public://' . $path_prefix . $item['path'] . '.html';

  $options = $item['options'];

  $result = graphapi_class_build_class($classes, $options);

  $cid = _graphapi_class_get_cid($classes);
  _graphapi_class_cache_set($cid, $result);

  @drupal_mkdir(dirname($path), null, TRUE);
  file_put_contents($path, $result);
}

function graphapi_class_get_all() {
  static $classes;
  if (!isset($classes)) {
    $classes = &drupal_static(__FUNCTION__, array());
  }
  else {
    return $classes;
  }
  graphapi_loader();
  $loader = drupal_classloader();
  // Directories to look for
  $prefixes = $loader->getPrefixes();

  $root = $_SERVER["DOCUMENT_ROOT"];

  $skip_prefixes = array(
    'Zend',
    'Symfony',
    'Twig', // Generates error: Class Twig/Autoloader.php does not exist
  );
  foreach ($prefixes as $prefix => $dirs) {
    $skip = FALSE;
    foreach ($skip_prefixes as $test_prefix) {
      if (strpos($prefix, $test_prefix) === 0) {
        $skip = TRUE;
      }
    }
    if ($skip) {
      watchdog('graphapi_class', "Skipping from exclude listfor '%prefix'", array('%prefix' => $prefix), WATCHDOG_NOTICE);
      continue;
    }

    foreach ($dirs as $dir) {

      $class_finder = new Finder();
      try {
        // @see http://symfony.com/doc/current/components/finder.html
        // We scan each directory individually due to
        // - https://drupal.org/node/2176683 : We register invalid components to composer.json and in other ways
        $class_finder->files()->name('*.php')->in($dir);
      }
      catch (Exception $exc) {
        watchdog('graphapi_class', "Exception while scanning for '%prefix' directory '%dir'", array('%prefix' => $prefix, '%dir' => $dir), WATCHDOG_WARNING);
        continue;
      }
      foreach ($class_finder as $file) {
        // Path relative to it's scan dir
        $real_path = $file->getRealPath();
        $path = str_replace($root, '', $real_path);
        $class = $file->getRelativePathname();
        // scrub .php and toggle /
        $class = preg_replace("/.php$/", '', $class);
        $class = str_replace('/', '\\', $class);
        $classes[$path] = $class;
      }
    }
  }

  watchdog('graphapi_class', "Found %count classes and interfaces", array('%count' => count($classes)), WATCHDOG_INFO);

  return $classes;
}

/**
 * Implements hook_help().
 */
function graphapi_class_help($path, $arg) {
  if ($path == 'admin/help#graphapi_class') {
    $output = '';
    $output .= '<h3>' . t('About') . '</h3>';
    $output .= '<p>' . t('The Graph API sub module graphapi_class generates UML Diagrams') . '</p>';
    $output .= '<h3>' . t('Uses') . '</h3>';
    $output .= '<dl>';
    $output .= '<dt>' . t('Using input filter Class Diagram') . '</dt>';
    $output .= '<dd>' . 'FilterTrivialGraphFormat::help(TRUE)' . '</dd>';
    $output .= '</dl>';
    return $output;
  }
}