<?php
namespace Grav\Plugin;

use Grav\Common\Cache;
use Grav\Common\Plugin;
use Grav\Common\Uri;

class ProblemsPlugin extends Plugin
{
 protected $results = array();

 protected $check;

 /**
 * @return array
 */
 public static function getSubscribedEvents()
 {
 return [
 'onPluginsInitialized' => ['onPluginsInitialized', 100001],
 'onFatalException' => ['onFatalException', 0]
 ];
 }

 public function onFatalException()
 {
 if ($this->isAdmin()) {
 $this->active = false;
 return;
 }

 // Run through potential issues
 if ($this->problemChecker()) {
 $this->renderProblems();
 }
 }

 public function onPluginsInitialized()
 {
 if ($this->isAdmin()) {
 $this->active = false;
 return;
 }

 /** @var Cache $cache */
 $cache = $this->grav['cache'];
 $validated_prefix = 'problem-check-';

 $this->check = CACHE_DIR . $validated_prefix . $cache->getKey();

 if (!file_exists($this->check)) {
 // If no issues remain, save a state file in the cache
 if (!$this->problemChecker()) {
 // delete any existing validated files
 foreach (new \GlobIterator(CACHE_DIR . $validated_prefix . '*') as $fileInfo) {
 @unlink($fileInfo->getPathname());
 }

 // create a file in the cache dir so it only runs on cache changes
 touch($this->check);

 } else {
 $this->renderProblems();
 }

 }
 }

 protected function renderProblems()
 {
 $theme = 'antimatter';

 /** @var Uri $uri */
 $uri = $this->grav['uri'];
 $baseUrlRelative = $uri->rootUrl(false);
 $themeUrl = $baseUrlRelative . '/' . USER_PATH . basename(THEMES_DIR) . '/' . $theme;
 $problemsUrl = $baseUrlRelative . '/user/plugins/problems';

 $html = file_get_contents(__DIR__ . '/html/problems.html');

 /**
 * Process the results, ignore the statuses passed as $ignore_status
 *
 * @param $results
 * @param $ignore_status
 */
 $processResults = function ($results, $ignore_status) {
 $problems = '';

 foreach ($results as $key => $result) {
 if ($key == 'files' || $key == 'apache' || $key == 'execute') {
 foreach ($result as $key_text => $value_text) {
 foreach ($value_text as $status => $text) {
 if ($status == $ignore_status) continue;
 $problems .= $this->getListRow($status, '<b>' . $key_text . '</b> ' . $text);
 }
 }
 } else {
 foreach ($result as $status => $text) {
 if ($status == $ignore_status) continue;
 $problems .= $this->getListRow($status, $text);
 }
 }
 }

 return $problems;
 };

 // First render the errors
 $problems = $processResults($this->results, 'success');

 // Then render the successful checks
 $problems .= $processResults($this->results, 'error');

 $html = str_replace('%%BASE_URL%%', $baseUrlRelative, $html);
 $html = str_replace('%%THEME_URL%%', $themeUrl, $html);
 $html = str_replace('%%PROBLEMS_URL%%', $problemsUrl, $html);
 $html = str_replace('%%PROBLEMS%%', $problems, $html);

 echo $html;
 http_response_code(500);

 exit();


 }

 protected function getListRow($status, $text)
 {
 if ($status == 'error') {
 $icon = 'fa-times';
 } elseif ($status == 'info') {
 $icon = 'fa-info';
 } else {
 $icon = 'fa-check';
 }
 $output = "\n";
 $output .= '<li class="' . $status . ' clearfix"><i class="fa fa-fw '. $icon . '"></i><p>'. $text . '</p></li>';
 return $output;
 }

 protected function problemChecker()
 {
 $min_php_version = defined('GRAV_PHP_MIN') ? GRAV_PHP_MIN : '5.4.0';
 $problems_found = false;

 $essential_files = [
 'cache' => true,
 'logs' => true,
 'images' => true,
 'assets' => true,
 'system' => false,
 'user/data' => true,
 'user/pages' => false,
 'user/config' => false,
 'user/plugins/error' => false,
 'user/plugins' => false,
 'user/themes' => false,
 'vendor' => false
 ];

 if (version_compare(GRAV_VERSION, '0.9.27', ">=")) {
 $essential_files['backup'] = true;
 $backup_folder = ROOT_DIR . 'backup';
 // try to create backup folder if missing
 if (!file_exists($backup_folder)) {
 @mkdir($backup_folder, 0770);
 }
 }

 if (version_compare(GRAV_VERSION, '1.1.4', ">=")) {
 $essential_files['tmp'] = true;
 $tmp_folder = ROOT_DIR . 'tmp';
 // try to create tmp folder if missing
 if (!file_exists($tmp_folder)) {
 @mkdir($tmp_folder, 0770);
 }
 }

 // Perform some Apache checks
 if (strpos(php_sapi_name(), 'apache') !== false) {

 $require_apache_modules = ['mod_rewrite'];
 $apache_modules = apache_get_modules();

 $apache_status = [];

 foreach ($require_apache_modules as $module) {
 if (in_array($module, $apache_modules)) {
 $apache_module_adjective = ' Apache module is enabled';
 $apache_module_status = 'success';
 } else {
 $problems_found = true;
 $apache_module_adjective = ' Apache module is not installed or enabled';
 $apache_module_status = 'error';
 }
 $apache_status[$module] = [$apache_module_status => $apache_module_adjective];
 }

 if (sizeof($apache_status) > 0) {
 $this->results['apache'] = $apache_status;
 }
 }

 // Check PHP version
 if (version_compare(phpversion(), $min_php_version, '<')) {
 $problems_found = true;
 $php_version_adjective = 'lower';
 $php_version_status = 'error';

 } else {
 $php_version_adjective = 'greater';
 $php_version_status = 'success';
 }
 $this->results['php'] = [$php_version_status => 'Your PHP version (' . phpversion() . ') is '. $php_version_adjective . ' than the minimum required: <b>' . $min_php_version . '</b> - <a href="http://getgrav.org/blog/changing-php-requirements-to-5.5">Additional Information</a>'];

 // Check for GD library
 if (defined('GD_VERSION') && function_exists('gd_info')) {
 $gd_adjective = '';
 $gd_status = 'success';
 } else {
 $problems_found = true;
 $gd_adjective = 'not ';
 $gd_status = 'error';
 }
 $this->results['gd'] = [$gd_status => 'PHP GD (Image Manipulation Library) is '. $gd_adjective . 'installed'];

 // Check for PHP CURL library
 if (function_exists('curl_version')) {
 $curl_adjective = '';
 $curl_status = 'success';
 } else {
 $problems_found = true;
 $curl_adjective = 'not ';
 $curl_status = 'error';
 }
 $this->results['curl'] = [$curl_status => 'PHP Curl (Data Transfer Library) is '. $curl_adjective . 'installed'];

 // Check for PHP Open SSL library
 if (extension_loaded('openssl') && defined('OPENSSL_VERSION_TEXT')) {
 $ssl_adjective = '';
 $ssl_status = 'success';
 } else {
 $problems_found = true;
 $ssl_adjective = 'not ';
 $ssl_status = 'error';
 }
 $this->results['ssl'] = [$ssl_status => 'PHP OpenSSL (Secure Sockets Library) is '. $ssl_adjective . 'installed'];

 // Check for PHP XML library
 if (extension_loaded('xml')) {
 $xml_adjective = '';
 $xml_status = 'success';
 } else {
 $problems_found = true;
 $xml_adjective = 'not ';
 $xml_status = 'error';
 }
 $this->results['xml'] = [$xml_status => 'PHP XML Library is '. $xml_adjective . 'installed'];

 // Check for PHP MbString library
 if (extension_loaded('mbstring')) {
 $mbstring_adjective = '';
 $mbstring_status = 'success';
 } else {
 $problems_found = true;
 $mbstring_adjective = 'not ';
 $mbstring_status = 'error';
 }
 $this->results['mbstring'] = [$mbstring_status => 'PHP Mbstring (Multibyte String Library) is '. $mbstring_adjective . 'installed'];

 // Check Exif if enabled
 if ($this->grav['config']->get('system.media.auto_metadata_exif')) {
 if(extension_loaded('exif')) {
 $exif_adjective = '';
 $exif_status = 'success';
 } else {
 $problems_found = true;
 $exif_adjective = 'not ';
 $exif_status = 'error';
 }
 $this->results['exif'] = [$exif_status => 'PHP Exif (Exchangeable Image File Format) is '. $exif_adjective . 'installed'];
 }

 // Check for PHP Zip library
 if (extension_loaded('zip')) {
 $zip_adjective = '';
 $zip_status = 'success';
 } else {
 $problems_found = true;
 $zip_adjective = 'not ';
 $zip_status = 'error';
 }
 $this->results['zip'] = [$zip_status => 'PHP Zip extension is '. $zip_adjective . 'installed'];

 // Check for essential files & perms
 $file_problems = [];
 foreach ($essential_files as $file => $check_writable) {
 $file_path = ROOT_DIR . $file;
 $is_dir = false;
 if (!file_exists($file_path)) {
 $problems_found = true;
 $file_status = 'error';
 $file_adjective = 'does not exist';

 } else {
 $file_status = 'success';
 $file_adjective = 'exists';
 $is_writeable = is_writable($file_path);
 $is_dir = is_dir($file_path);

 if ($check_writable) {
 if (!$is_writeable) {
 $file_status = 'error';
 $problems_found = true;
 $file_adjective .= ' but is <b class="underline">not writeable</b>';
 } else {
 $file_adjective .= ' and <b class="underline">is writeable</b>';
 }
 }
 }

 $file_problems[$file_path] = [$file_status => $file_adjective];

 }
 if (sizeof($file_problems) > 0) {
 $this->results['files'] = $file_problems;
 }

 return $problems_found;
 }
}