<?php

/**
 * @file
 * Provides Browser Class settings form, permission, and browser detection.
 */

define('BROWSERCLASS_OPERATION_WITHOUT_JS', 0);
define('BROWSERCLASS_OPERATION_WITH_JS', 1);

/**
 * Class masks - defines the kind of the classes.
 */
define('BROWSERCLASS_BROWSER', 1);
define('BROWSERCLASS_PLATFORM', 2);
define('BROWSERCLASS_MOBILE', 4);
define('BROWSERCLASS_OTHER_CLASSES', 8);
define('BROWSERCLASS_ALL',
  BROWSERCLASS_BROWSER |
  BROWSERCLASS_PLATFORM |
  BROWSERCLASS_MOBILE |
  BROWSERCLASS_OTHER_CLASSES
);

/**
 * Implements hook_menu().
 */
function browserclass_menu() {
  $items = [];

  $items['admin/config/user-interface/browserclass'] = [
    'title'            => 'Browser class',
    'page callback'    => 'drupal_get_form',
    'page arguments'   => ['browserclass_settings_form'],
    'access arguments' => ['administer browser class'],
  ];

  return $items;
}

/**
 * Implements hook_permission().
 */
function browserclass_permission() {
  return [
    'administer browser class' => [
      'title'           => 'Administer browser class',
      'description'     => 'Configure Browser class module, set JavaScript operation.',
      'restrict access' => TRUE,
    ],
  ];
}

/**
 * Implements hook_page_build().
 */
function browserclass_page_build(&$page) {

  if (((variable_get('browserclass_operation', BROWSERCLASS_OPERATION_WITHOUT_JS) == BROWSERCLASS_OPERATION_WITH_JS)
      || variable_get('cache', 0) != 0) && (browserclass_get_classes())) {

    $page['page_bottom']['#attached']['js'] = [
      drupal_get_path('module', 'browserclass') . '/js/browserclass.js' => [
        'type'  => 'file',
        'scope' => 'footer',
      ],
    ];
  }
}

/**
 * Implements hook_preprocess_HOOK().
 */
function browserclass_preprocess_html(&$variables) {

  if ((variable_get('browserclass_operation', BROWSERCLASS_OPERATION_WITHOUT_JS) == BROWSERCLASS_OPERATION_WITHOUT_JS) &&
    (variable_get('cache', 0) == 0) && ($browser_classes = browserclass_get_classes())) {

    $variables['classes_array'] = array_merge($variables['classes_array'], $browser_classes);
    $variables['browser_classes'] = $browser_classes;
  }
}

/**
 * Provide Browser Class settings form.
 */
function browserclass_settings_form() {

  $form = [];

  $form['browserclass_operation'] = [
    '#type'          => 'radios',
    '#title'         => t('Operation'),
    '#options'       => [
      BROWSERCLASS_OPERATION_WITH_JS    => t('Always add the class with JavaScript'),
      BROWSERCLASS_OPERATION_WITHOUT_JS => t('Only use JavaScript if page cache is enabled'),
    ],
    '#default_value' => variable_get('browserclass_operation', BROWSERCLASS_OPERATION_WITHOUT_JS),
  ];

  return system_settings_form($form);
}

/**
 * Get classes.
 *
 * @return array
 *   An array of browser classes.
 */
function browserclass_get_classes($types = BROWSERCLASS_ALL) {
  $classes = [];

  // User agent doesn't set always, for example on rss readers.
  if (isset($_SERVER['HTTP_USER_AGENT'])) {
    $agent = strtolower($_SERVER['HTTP_USER_AGENT']);

    if ($types & BROWSERCLASS_BROWSER) {
      $classes = array_merge($classes, browserclass_check_browser($agent));
    }

    if ($types & BROWSERCLASS_PLATFORM) {
      $classes = array_merge($classes, browserclass_check_platform($agent));
    }

    if ($types & BROWSERCLASS_OTHER_CLASSES) {
      // Merge other modules classes.
      $classes = array_merge($classes, module_invoke_all('browserclass_classes', $agent));
    }

    if ($types & BROWSERCLASS_MOBILE) {
      $classes[] = browserclass_is_mobile_devide($agent, $classes) ? 'mobile' : 'desktop';
    }
  }

  return $classes;
}

/**
 * Detect browser.
 *
 * @param string $agent
 *   Lowercase version of user agent.
 *
 * @return array
 *   An array of detected platforms.
 */
function browserclass_check_browser($agent) {
  $classes = [];

  // Add IE extra class with the version number.
  $ie_pattern = '/(?:\b(ms)?ie\s+|\btrident\/7\.0;.*\s+rv:)(\d+)/';
  $ie_matches = [];
  $ie_m = preg_match($ie_pattern, $agent, $ie_matches);

  if ($ie_m === 1) {
    $classes[] = 'ie';

    if (isset($ie_matches[2])) {
      $classes[] = 'ie' . $ie_matches[2];
    }
  }

  if (stristr($agent, 'opera') !== FALSE) {
    $classes[] = 'opera';
    $aresult = explode('/', stristr($agent, 'version'));
    if (isset($aresult[1])) {
      $aversion = explode(' ', $aresult[1]);
      $classes[] = 'opera' . _browserclass_clear_version($aversion[0]);
    }
  }

  // Check for chrome desktop first, then chrome mobile, lastly check for
  // safari, as these are mutually exclusive.
  if (stristr($agent, 'chrome') !== FALSE) {
    $classes[] = 'chrome';
    $aresult = explode('/', stristr($agent, 'chrome'));
    $aversion = explode(' ', $aresult[1]);
    $classes[] = 'chrome' . _browserclass_clear_version($aversion[0]);
  }
  elseif (stristr($agent, 'crios') !== FALSE) {
    $classes[] = 'chrome';

    $aresult = explode('/', stristr($agent, 'crios'));
    if (isset($aresult[1])) {
      $aversion = explode(' ', $aresult[1]);
      $classes[] = 'chrome' . _browserclass_clear_version($aversion[0]);
    }
  }
  elseif (stristr($agent, 'safari') !== FALSE) {
    $classes[] = 'safari';

    $aresult = explode('/', stristr($agent, 'version'));
    if (isset($aresult[1])) {
      $aversion = explode(' ', $aresult[1]);
      $classes[] = 'safari' . _browserclass_clear_version($aversion[0]);
    }
  }

  if (stristr($agent, 'netscape') !== FALSE) {
    $classes[] = 'netscape';
    if (preg_match('/navigator\/([^ ]*)/', $agent, $matches)) {
      $classes[] = 'netscape' . _browserclass_clear_version($matches[1]);
    }
    elseif (preg_match('/netscape6?\/([^ ]*)/', $agent, $matches)) {
      $classes[] = 'netscape' . _browserclass_clear_version($matches[1]);
    }
  }

  if (stristr($agent, 'firefox') !== FALSE) {
    $classes[] = 'ff';

    if (preg_match("/firefox[\/ \(]([^ ;\)]+)/", $agent, $matches)) {
      $classes[] = 'ff' . _browserclass_clear_version($matches[1]);
    }
  }

  if (stristr($agent, 'konqueror') !== FALSE) {
    $classes[] = 'konqueror';
    $aresult = explode(' ', stristr($agent, 'konqueror'));
    $aversion = explode('/', $aresult[0]);
    $classes[] = 'konqueror' . _browserclass_clear_version($aversion[1]);
  }

  if (stristr($agent, 'dillo') !== FALSE) {
    $classes[] = 'dillo';
  }

  if (stristr($agent, 'chimera') !== FALSE) {
    $classes[] = 'chimera';
  }

  if (stristr($agent, 'beonex') !== FALSE) {
    $classes[] = 'beonex';
  }

  if (stristr($agent, 'aweb') !== FALSE) {
    $classes[] = 'aweb';
  }

  if (stristr($agent, 'amaya') !== FALSE) {
    $classes[] = 'amaya';
  }

  if (stristr($agent, 'icab') !== FALSE) {
    $classes[] = 'icab';
  }

  if (stristr($agent, 'lynx') !== FALSE) {
    $classes[] = 'lynx';
  }

  if (stristr($agent, 'galeon') !== FALSE) {
    $classes[] = 'galeon';
  }

  if (stristr($agent, 'opera mini') !== FALSE) {
    $classes[] = 'operamini';

    $resultant = stristr($agent, 'opera mini');
    if (preg_match('/\//', $resultant)) {
      $aresult = explode('/', $resultant);
      $aversion = explode(' ', $aresult[1]);
      $classes[] = 'operamini' . _browserclass_clear_version($aversion[0]);
    }
    else {
      $aversion = explode(' ', stristr($resultant, 'opera mini'));
      $classes[] = 'operamini' . _browserclass_clear_version($aversion[1]);
    }
  }

  return $classes;
}

/**
 * Detect platform.
 *
 * @param string $agent
 *   Lowercase version of user agent.
 *
 * @return array
 *   An array of detected platforms.
 */
function browserclass_check_platform($agent) {
  $classes = [];

  if (stristr($agent, 'windows') !== FALSE) {
    $classes[] = 'win';
  }
  elseif (stristr($agent, 'ipad') !== FALSE) {
    $classes[] = 'ipad';
  }
  elseif (stristr($agent, 'ipod') !== FALSE) {
    $classes[] = 'ipod';
  }
  elseif (stristr($agent, 'iphone') !== FALSE) {
    $classes[] = 'iphone';
  }
  elseif (stristr($agent, 'mac') !== FALSE) {
    $classes[] = 'mac';
  }
  elseif (stristr($agent, 'android') !== FALSE) {
    $classes[] = 'android';
  }
  elseif (stristr($agent, 'linux') !== FALSE) {
    $classes[] = 'linux';
  }
  elseif (stristr($agent, 'nokia') !== FALSE) {
    $classes[] = 'nokia';
  }
  elseif (stristr($agent, 'blackberry') !== FALSE) {
    $classes[] = 'blackberry';
  }
  elseif (stristr($agent, 'freebsd') !== FALSE) {
    $classes[] = 'freebsd';
  }
  elseif (stristr($agent, 'openbsd') !== FALSE) {
    $classes[] = 'openbsd';
  }
  elseif (stristr($agent, 'netbsd') !== FALSE) {
    $classes[] = 'netbsd';
  }

  return $classes;
}

/**
 * Check if device is a mobile device.
 *
 * @return bool
 *   TRUE if mobile device, FALSE otherwise.
 */
function browserclass_is_mobile_devide($agent, $classes) {
  $mobile_devices = [
    'ipad',
    'ipod',
    'iphone',
    'android',
    'blackberry',
    'operamini',
  ];

  foreach ($mobile_devices as $mobile) {
    if (in_array($mobile, $classes)) {
      return TRUE;
    }
  }

  if (isset($_SERVER['HTTP_X_WAP_PROFILE']) || isset($_SERVER['HTTP_PROFILE'])) {
    return TRUE;
  }

  if (preg_match('/(up.browser|up.link|mmp|symbian|smartphone|midp|wap|vodafone|o2|pocket|kindle|mobile|pda|psp|treo)/', $agent)) {
    return TRUE;
  }

  return FALSE;
}

/**
 * Remove unsupported characters from version.
 *
 * @param string $version
 *   A version string.
 *
 * @return string
 *   Sanitized version string.
 */
function _browserclass_clear_version($version) {
  $version = preg_replace('/[^0-9,.,a-z,A-Z-]/', '', $version);
  return substr($version, 0, strpos($version, '.'));
}