<?php

/**
 * Implements hook_help().
 */
function mobile_theme_help($path, $arg) {
  $output = '';
  switch ($path) {
    // Main module help for the block module
    case 'admin/help#mobile_theme':
      $output .= '<p>' . t('Adds the ability to choose which theme is used when the user visits the site using a mobile device.') . '</p>';
      $output .= theme('item_list', array(
        'title' => t('Instructions'),
        'type' => 'ol',
        'items' => array(
          t('Visit the <a href="@appearance">Appearance settings</a>.', array('@appearance' => url('admin/appearance/settings'))),
          t('Choose the mobile theme that will be used when the user is on a mobile device.'),
          t('You might want to install one of the alternative device detection method as outlined below.'),
        ),
      ));
      $output .= theme('item_list', array(
        'title' => t('Alternative detection methods'),
        'items' => array(
          'Browscap' => array(
            'data' => t('Browscap'),
            'children' => array(
              t('Install the <a href="@browscap">Browscap</a> Drupal module.', array('@browscap' => 'http://drupal.org/project/browscap')),
              t('Select Browscap in the <a href="@appearance">Appearance settings</a>.', array('@appearance' => url('admin/appearance/settings'))),
            ),
          ),
          'Mobile Device Detect' => array(
            'data' => t('Mobile Device Detect'),
            'children' => array(
              t('Visit <a href="@detectmobilebrowsers">http://detectmobilebrowsers.mobi</a>.', array('@detectmobilebrowsers' => 'http://detectmobilebrowsers.mobi')),
              t('<a href="@download">Download the code</a> and extract it to the Mobile Theme module directory.', array('@download' => url('http://detectmobilebrowsers.mobi/?dl'))),
              t('You should end up with <code>@path</code>.', array('@path' => drupal_get_path('module', 'mobile_theme') . '/mobile_device_detect.php')),
              t('It is recommended you <a href="@upgrade">upgrade</a> if on a commercial site.', array('@upgrade' => drupal_get_path('module', 'mobile_theme') . '/upgrade.php')),
              t('Select Mobile Device Detect in the <a href="@appearance">Appearance settings</a>.', array('@appearance' => url('admin/appearance/settings'))),
            ),
          ),
        ),
      ));
  }
  return $output;
}

/**
 * Implements hook_custom_theme().
 */
function mobile_theme_custom_theme() {
  // Retrieve the detection method.
  $method = variable_get('mobile_theme_detection', 'mobile_theme_detect_php');

  // If the detection method cannot be found, revert to default
  if (!function_exists($method)) {
    $method = "mobile_theme_detect_php";
  }

  // Check if this is a mobile 
  $mobile_device = $method();
  if ($mobile_device) {
    $theme = variable_get('mobile_theme_selection', 'default');
    if ($theme != 'default') {
      return $theme;
    }
  }
}

/**
 * Implements hook_mobile_theme_detection().
 */
function mobile_theme_mobile_theme_detection() {
  // Provide get_browser by default.
  $detection_methods = array(
    'mobile_theme_detect_php' => t('PHP'),
    'mobile_theme_detect_getbrowser' => t('get_browser'),
  );

  // Support Browscap module if available.
  if (module_exists('browscap')) {
    $detection_methods['mobile_theme_detect_browscap']  = t('Browscap');
  }

  // Support for http://detectmobilebrowsers.mobi .
  if (file_exists(drupal_get_path('module', 'mobile_theme') . '/mobile_device_detect.php')) {
    $detection_methods['mobile_theme_detect_mobiledevicedetect']  = t('Mobile Device Detect');
  }
  return $detection_methods;
}

/**
 * Detect whether the user is on a mobile device by using get_browser.
 */
function mobile_theme_detect_getbrowser() {
  $browser = get_browser(NULL, TRUE);
  if (isset($browser['ismobiledevice'])) {
    return $browser['ismobiledevice'];
  }
}

/**
 * Detect whether the user is on a mobile device using straight PHP.
 */
function mobile_theme_detect_php() {
  $mobile_browser = 0;
  if (preg_match('/(up.browser|up.link|mmp|symbian|smartphone|midp|wap|phone|android)/i', strtolower($_SERVER['HTTP_USER_AGENT']))) {
    $mobile_browser++;
  }
  if ((isset($_SERVER['HTTP_ACCEPT']) && strpos(strtolower($_SERVER['HTTP_ACCEPT']),'application/vnd.wap.xhtml+xml') > 0) or ((isset($_SERVER['HTTP_X_WAP_PROFILE']) or isset($_SERVER['HTTP_PROFILE'])))) {
    $mobile_browser++;
  }
  $mobile_ua = strtolower(substr($_SERVER['HTTP_USER_AGENT'], 0, 4));
  $mobile_agents = array(
      'w3c ','acs-','alav','alca','amoi','audi','avan','benq','bird','blac',
      'blaz','brew','cell','cldc','cmd-','dang','doco','eric','hipt','inno',
      'ipaq','java','jigs','kddi','keji','leno','lg-c','lg-d','lg-g','lge-',
      'maui','maxo','midp','mits','mmef','mobi','mot-','moto','mwbp','nec-',
      'newt','noki','oper','palm','pana','pant','phil','play','port','prox',
      'qwap','sage','sams','sany','sch-','sec-','send','seri','sgh-','shar',
      'sie-','siem','smal','smar','sony','sph-','symb','t-mo','teli','tim-',
      'tosh','tsm-','upg1','upsi','vk-v','voda','wap-','wapa','wapi','wapp',
      'wapr','webc','winw','winw','xda ','xda-');
  if (in_array($mobile_ua,$mobile_agents)) {
    $mobile_browser++;
  }
  if (isset($_SERVER['ALL_HTTP']) && strpos(strtolower($_SERVER['ALL_HTTP']), 'OperaMini') > 0) {
    $mobile_browser++;
  }
  if (strpos(strtolower($_SERVER['HTTP_USER_AGENT']), 'windows') > 0) {
    $mobile_browser = 0;
  }
  return $mobile_browser > 0; 
}

/**
 * Detect whether the user is on a mobile device by using Browscap.
 */
function mobile_theme_detect_browscap() {
  $browser = browscap_get_browser(NULL);
  if (isset($browser['ismobiledevice'])) {
    return $browser['ismobiledevice'];
  }
}

/**
 * Detect whether the user is on a mobile device by using Mobile Device Detect.
 */
function mobile_theme_detect_mobiledevicedetect() {
  // Include mobile_device_detect.php so that we can use it.
  if (module_load_include('php', 'mobile_theme', 'mobile_device_detect') != FALSE) {
    return mobile_device_detect();
  }
  else {
    // Display a warning if the detection method was not found.
    drupal_set_message(t('<em>Mobile Device Detect</em> is not installed. Visit the <a href="@adminhelpmobiletheme">documentation on Mobile Theme</a> for more installation instructions.', array(
      '@adminhelpmobiletheme' => url('admin/help/mobile_theme'),
    )), 'warning');
    return FALSE;
  }
}

/**
 * Alter the system theme settings form to add the mobile theme settings.
 */
function mobile_theme_form_system_theme_settings_alter(&$form, $form_state, $form_id) {
  // Create the administration settings form on the Global Settings page.
  if ($form['var']['#value'] == 'theme_settings') {
    // Create the fieldset for the Mobile Theme settings.
    $form['mobile_theme'] = array(
      '#type' => 'fieldset',
      '#prefix' => '<div class="theme-settings-right">',
      '#suffix' => '</div>',
      '#title' => t('Mobile theme'),
      '#description' => t('Configure how the site reacts to a mobile device.'),
      '#weight' => -4,
    );
    // Select box for the detection method.
    $form['mobile_theme']['mobile_theme_detection'] = array(
      '#type' => 'select',
      '#title' => t('Detection method'),
      '#description' => t('Choose which method will be used to detect mobile devices. Visit the <a href="@help">help documentation</a> for information on how to add other device detection methods.', array(
        '@help' => url('admin/help/mobile_theme'),
      )),
      '#options' => module_invoke_all('mobile_theme_detection'),
      '#default_value' => variable_get('mobile_theme_detection', 'mobile_theme_detect_php'),
    );
    // Select box for the theme to be used for mobile devices.
    $themes = array('default' => t('Default'));
    $options = list_themes();
    foreach ($options as $name => $attr) {
      if ($attr->status) {
        $themes[$name] = $attr->info['name'];
      }
    }
    $form['mobile_theme']['mobile_theme_selection'] = array(
      '#type' => 'select',
      '#title' => 'Mobile theme',
      '#description' => t('The theme to use when serving a mobile device.'),
      '#options' => $themes,
      '#default_value' => variable_get('mobile_theme_selection', 'default'),
    );
    // The submit handler will save the variable.
    $form['#submit'][] = 'mobile_theme_settings_submit';
  }
}

/**
 * Submit handler on the theme settings to save the mobile theme.
 */
function mobile_theme_settings_submit($form, $form_state) {
  if (isset($form_state['values']['mobile_theme_selection'])) {
    variable_set('mobile_theme_selection', $form_state['values']['mobile_theme_selection']);
  }
  if (isset($form_state['values']['mobile_theme_detection'])) {
    variable_set('mobile_theme_detection', $form_state['values']['mobile_theme_detection']);
  }
}