<?php
// $Id: gallery_install.inc,v 1.1.2.29 2009-01-10 10:37:00 profix898 Exp $

/**
 * gallery.module : gallery_install.inc
 * Configure embedded Gallery install (directory options, etc.)
 */

define('GALLERY_INSTALL_STEP_PHPMEMORY',  1);
define('GALLERY_INSTALL_STEP_LOCATIONS',  2);
define('GALLERY_INSTALL_STEP_PLUGINS',    3);
define('GALLERY_INSTALL_STEP_URLREWRITE', 4);
define('GALLERY_INSTALL_STEP_USERSYNC',   5);

/**
 * Function _gallery_install().
 */
function _gallery_install($form_values = NULL) {
  $form['#multistep'] = TRUE;
  $form['#redirect'] = FALSE;
  $form['#submit']['_gallery_install_submit'] = array();
  
  $install_status = array(
    'phpmemory' => array(
      'title' => 'PHP Memory Limit',
      'severity' => GALLERY_SEVERITY_ERROR,
    ),
    'locations' => array(
      'title' => 'Gallery2 locations',
      'severity' => GALLERY_SEVERITY_ERROR,
    ),
    'plugins' => array(
      'title' => 'Drupal Modules / Gallery2 Plugins',
      'severity' => GALLERY_SEVERITY_WARNING,
    ),
    'cleanurls' => array(
      'title' => 'Clean URL / URL Rewrite',
      'severity' => GALLERY_SEVERITY_WARNING,
    ),
    'usersync' => array(
      'title' => 'Initial User Synchronization',
      'severity' => GALLERY_SEVERITY_ERROR,
    ),
  );

  if (!isset($form_values)) {
    $form_values = array();
    $form_values['step'] = GALLERY_INSTALL_STEP_PHPMEMORY;
    $form_values['gallery_valid'] = FALSE;
    $form_values['initial_check'] = TRUE;
    if (variable_get('gallery_config_reset', FALSE)) {
      $form_values['initial_check'] = FALSE;
      variable_del('gallery_config_reset');
    }
  }
  else {
    // Work around a D5 design flaw
    // manage $form_values to allow the same form to be submitted more than once
    $form_values = unserialize(variable_get('gallery_wizard_data', array()));
    $form_values['initial_check'] = FALSE;
  }
  
  $form['install_status'] = array(
    '#type' => 'fieldset',
    '#title' => t('Install status'),
    '#collapsible' => FALSE,
    '#collapsed' => FALSE,
    '#description' => t('Correct configuration of the following items is essential for the embedded gallery to function properly.'),
  );
  
  // Step 1: Check PHP Memory
  if ($form_values['step'] >= GALLERY_INSTALL_STEP_PHPMEMORY) {
    _gallery_install_step_php_memory($form, $form_values, $install_status);
  }

  // Step 2 : Gallery2 Locations
  if ($form_values['step'] >= GALLERY_INSTALL_STEP_LOCATIONS) {
    _gallery_install_step_locations($form, $form_values, $install_status);
  }
  
  // Step 3: Drupal Modules and Gallery2 Plugins check
  if ($form_values['step'] >= GALLERY_INSTALL_STEP_PLUGINS) {
    _gallery_install_step_plugins($form, $form_values, $install_status);
  }

  // Step 4: Clean URL configuration
  if ($form_values['step'] >= GALLERY_INSTALL_STEP_URLREWRITE) {
    _gallery_install_step_urlrewrite($form, $form_values, $install_status);
  }
  
  // Step 5: User Synchronization
  if ($form_values['step'] >= GALLERY_INSTALL_STEP_USERSYNC) {
    _gallery_install_step_usersync($form, $form_values, $install_status);
  }
  
  $form['initial_check'] = array(
    '#type' => 'hidden',
    '#value' => $form_values['initial_check'],
  );
  $form['gallery_valid'] = array(
    '#type' => 'hidden',
    '#value' => $form_values['gallery_valid'],
  );
  $form['plugins_valid'] = array(
    '#type' => 'hidden',
    '#value' => $form_values['plugins_valid'],
  );
  $form['step'] = array(
    '#type' => 'hidden',
    '#value' => $form_values['step'],
  );
  
  $form['buttons']['reset'] = array('#type' => 'submit', '#value' => t('Reset & Restart'));

  // Set the global status variable 'gallery_valid'
  gallery_set_status(array(
    'gallery_valid' => array(
      'title' => t('Overall Status (Installation)'),
      'severity' => $form_values['gallery_valid'] ? GALLERY_SEVERITY_SUCCESS : GALLERY_SEVERITY_ERROR,
    ),
  ));
  
  // Create install status table
  $error = FALSE;
  $rows = array();
  foreach ($install_status as $key => $step_status) {
    // Find the combination of status and severity of the plugin
    $severity = ($step_status['status'] <= 0) ? $step_status['severity'] : GALLERY_SEVERITY_SUCCESS; 
    if (!$step_status['status']) {
      $error = TRUE;
    }   
    $row = array();
    $row[] = array('data' => $step_status['title'], 'align' => 'left', 'width' => '20%');
    $row[] = array('data' => theme('gallery_severity_message', $severity), 'align' => 'center');
    $row[] = array('data' => $step_status['info'], 'class' => 'description', 'id' => 'gallery-install-status-'. $key);
    $rows[] = $row;
  }
  if ($error && !$form_values['initial_check']) {
    $rows[] = array(array(
      'data' => t('Critical errors are present. Your Gallery is not available.'), 
      'colspan' => '3', 
      'align' => 'center', 
      'class' => 'message')
    );
  }
  $header = array('Step', 'Status', 'Description');
  $form['install_status']['status']['#value'] = theme('table', $header, $rows, array('class' => 'package'));
  
  return $form;
}

/**
 * Function _gallery_install_step_php_memory().
 * Step 1: Check PHP Memory
 */ 
function _gallery_install_step_php_memory(&$form, &$form_values, &$install_status) {
  $phpmemory_info = _gallery_php_mem_check();
  $desc = $phpmemory_info['info'];
  if (!$phpmemory_info['status']) {
    $desc .= ' '. t('Until this is fixed your Gallery2 cannot be installed.');
    $form_values['step'] = GALLERY_INSTALL_STEP_PHPMEMORY;
  }
  else {
    $form_values['step']++;
  }
  
  $form['phpmemory'] = array(
    '#type' => 'fieldset',
    '#title' => t('Step 1: PHP Memory Test') . ($phpmemory_info['status'] ? ' '. t('(OK)') : ''),
    '#description' => $desc,
    '#collapsible' => ($form_values['step'] > GALLERY_INSTALL_STEP_PHPMEMORY),
    '#collapsed' => $phpmemory_info['status'],
  );
  if (!$phpmemory_info['status']) {
    $form['phpmemory']['check'] = array('#type' => 'submit', '#value' => t('Check PHP memory again'));      
  }
  
  $install_status['phpmemory']['status'] = $phpmemory_info['status'];
  $install_status['phpmemory']['info'] = $phpmemory_info['info'];
}

/**
 * Function _gallery_install_step_locations().
 * Step 2: Gallery2 Locations
 */ 
function _gallery_install_step_locations(&$form, &$form_values, &$install_status) {
  if ($form_values['step'] > GALLERY_INSTALL_STEP_LOCATIONS || $form_values['initial_check']) {
    _gallery_install_locations($form, $form_values, $install_status);
  }
  // Check was not successful. Don't proceed with step 3
  if (!$form_values['gallery_valid']) {
    $form_values['step'] = GALLERY_INSTALL_STEP_LOCATIONS;
  }
  else {
    $form_values['step']++;
  }

  $autodetect_dir = variable_get('gallery_autodetect_dir', 1);
  $extra = $autodetect_dir ? t('- Auto Configuration') : t('- Manual Configuration');
  // If 'initial_check' = True then this is the first time the user has come through this
  // step (or the wizard has been restarted). Allow the field to be edited EVEN IF VALID.
  // If 'initial_check' = False then this step has been completed already, so make read-only.
  if (!$form_values['gallery_valid']) {
    $desc = $autodetect_dir ?
      t('Enter the \'Gallery2 URL or URI\' and click \'Test location settings\'
        to automatically configure the settings needed for embedding Gallery2 into Drupal. Note that
        the auto-config will not work for all host configurations. If you have tried it with a value 
        you know is correct and it did not work then just use the manual configuration instead.') :
      t('Enter the \'Gallery2 URL or URI\' and \'Gallery2 filesystem path\' and then click 
        \'Test location settings\'. This will check and configure the settings needed for embedding
        Gallery2 into Drupal.');
  }
  else {
    $desc = '';
  }
  
  $form['install'] = array(
    '#type' => 'fieldset',
    '#title' => t('Step 2: Gallery2 location settings') .' '. $extra . ($form_values['gallery_valid'] ? ' '. t('(OK)') : ''),
    '#description' => isset($form['install']['#description']) ? ($desc .'<p>'. $form['install']['#description'] .'</p>') : $desc,
    '#collapsible' => ($form_values['step'] > GALLERY_INSTALL_STEP_LOCATIONS),
    '#collapsed' => $form_values['gallery_valid'],
  ); 
  
  // Only provide these values when autoconfig has been set. Otherwise the user might think
  // that these had been automatically figured out even though manual config was done.
  if ($autodetect_dir) {
    $gallery_uri = isset($form_values['gallery_uri_auto']) ? 
      $form_values['gallery_uri_auto'] : ($form_values['gallery_valid'] ? 
      variable_get('gallery_uri', '/gallery2/') : '');

    $gallery_dir = isset($form_values['gallery_dir_auto']) ? 
      $form_values['gallery_dir_auto'] : ($form_values['gallery_valid'] ? 
      variable_get('gallery_dir', './gallery2/') : '');
      
    $embed_uri = isset($form_values['gallery_embed_uri_auto']) ? 
      $form_values['gallery_embed_uri_auto'] : ($form_values['gallery_valid'] ? 
      variable_get('gallery_embed_uri', '?q=gallery') : '');
    $form['install']['gallery_uri_auto'] = array(
      '#type' => 'textfield',
      '#title' => t('Gallery2 URL or URI'),
      '#default_value' => $gallery_uri,
      '#size' => 64,
      '#maxlength' => 128,
      '#description' => t('URL or URI of the G2 standalone location. This can be either the full
        URL to Gallery2 (e.g. http://www.example.com/gallery2) or the path from docroot to the
        Gallery2 directory (e.g. /gallery2). If using a URI the protocol/hostname are both
        optional.'),
      '#disabled' => $form_values['gallery_valid'],
    );

    if (!empty($gallery_dir)) {
      $form['install']['gallery_dir_auto_item'] = array(
        '#title' => t('Gallery2 filesystem path'),
        '#type' => 'item',
        '#value' => $gallery_dir,
      );
    }
    $form['install']['gallery_dir_auto'] = array(
      '#type' => 'value',
      '#value' => $gallery_dir,
    );
    
    if (!empty($gallery_dir)) {
      $form['install']['gallery_embed_uri_auto_item'] = array(
        '#title' => t('Embed URI'),
        '#type' => 'item',
        '#value' => $embed_uri,
      );
    }
    $form['install']['gallery_embed_uri_auto'] = array(
      '#type' => 'value',
      '#value' => $embed_uri,
    );
  }
  else {
    $gallery_uri = isset($form_values['gallery_uri_man']) ? 
      $form_values['gallery_uri_man'] : ($form_values['gallery_valid'] ? 
      variable_get('gallery_uri', '/gallery2/') : '');
      
    $gallery_dir = isset($form_values['gallery_dir_man']) ? 
      $form_values['gallery_dir_man'] : ($form_values['gallery_valid'] ? 
      variable_get('gallery_dir', './gallery2/') : '');
      
    $embed_uri = isset($form_values['gallery_embed_uri_man']) ? 
      $form_values['gallery_embed_uri_man'] : ($form_values['gallery_valid'] ? 
      variable_get('gallery_embed_uri', '?q=gallery') : '');
      
    $form['install']['gallery_uri_man'] = array(
      '#type' => 'textfield',
      '#title' => t('Gallery2 URL or URI'),
      '#default_value' => $gallery_uri,
      '#size' => 64,
      '#maxlength' => 128,
      '#description' => t('URL or URI of the G2 standalone location. This can be either the full
        URL to Gallery2 (e.g. http://www.example.com/gallery2) or the path from docroot to the
        Gallery2 directory (e.g. /gallery2). If using a URI the protocol/hostname are both
        optional.'),
      '#disabled' => $form_values['gallery_valid'],
    );
    
    $form['install']['gallery_dir_man'] = array(
      '#type' => 'textfield',
      '#title' => t('Gallery2 filesystem path'),
      '#default_value' => $gallery_dir,
      '#size' => 64,
      '#maxlength' => 128,
      '#description' => t('The filesystem path of your Gallery2 directory. This can be either an
        absolute path (e.g. /home/mysite/htdocs/gallery2) or relative to the root directory of your
        Drupal installation (e.g. ../gallery2).'),
      '#disabled' => $form_values['gallery_valid'],
    );
  
    $form['install']['gallery_embed_uri_man'] = array(
      '#type' => 'textfield',
      '#title' => t('Embed URI'),
      '#default_value' => $embed_uri,
      '#size' => 64,
      '#maxlength' => 128,
      '#description' => t('URI to access G2 via Drupal. Don\'t worry if you are using clean urls in Drupal and this still ends in \'index.php?q=gallery\'. This is needed to get the Gallery2 URL rewrite module to work correctly and will not be visible.'),
      '#disabled' => $form_values['gallery_valid'],
    );
  }
  
  if (!$form_values['gallery_valid']) {
    $form['install']['location_button'] = array(
      '#type' => 'submit',
      '#value' => t('Test location settings'),
    );
    if ($autodetect_dir) {
      $form['install']['manual_config_button'] = array(
        '#type' => 'submit',
        '#value' => t('Use Manual Configuration'),
      );
    }
    else {
      $form['install']['auto_config_button'] = array(
        '#type' => 'submit',
        '#value' => t('Use Auto Configuration'),
      );
    }
  }
}

/**
 * Function _gallery_install_step_plugins().
 * Step 3: Drupal Modules / Gallery2 Plugins
 */ 
function _gallery_install_step_plugins(&$form, &$form_values, &$install_status) {  
  $form['plugins'] = array(
    '#type' => 'fieldset',
    '#title' => t('Step 3: Drupal Modules / Gallery2 Plugins'),
    '#collapsible' => ($form_values['step'] > GALLERY_INSTALL_STEP_PLUGINS),
    '#collapsed' => FALSE,
  );
  
  $header = array('Name', 'Status', 'Description');
  $overall_plugin_severity = GALLERY_SEVERITY_UNKNOWN - 1;
  $overall_plugin_status = GALLERY_PLUGIN_ENABLED;
  // Wanted (required) G2 plugins 
  $wanted_g2_plugins = gallery_wanted_plugin_info();
  $rows = array();
  foreach ($wanted_g2_plugins as $key => $module) {
    // Find the combination of status and severity of the plugin
    $severity = ($module['status'] != GALLERY_PLUGIN_ENABLED) ? $module['severity'] : GALLERY_SEVERITY_SUCCESS;
    $row = array();
    $row[] = array('data' => $module['title'], 'align' => 'left', 'width' => '15%');
    $row[] = array('data' => theme('gallery_severity_status_message', $severity, $module['status']), 'align' => 'center');
    $row[] = array('data' => $module['info'], 'class' => 'description', 'id' => 'gallery-install-plugin-'. $key);
    $rows[] = $row;
    if ($module['status'] != GALLERY_PLUGIN_ENABLED && $severity > $overall_plugin_severity) {
      $overall_plugin_severity = $severity;
      $overall_plugin_status = $module['status'];
    }
  }
  $form['plugins']['wanted_g2_plugins'] = array(
    '#type' => 'fieldset',
    '#title' => t('Recommended Gallery2 plugins'),
    '#collapsible' => FALSE,
    '#collapsed' => FALSE,
    '#value' => theme('table', $header, $rows, array('class' => 'package')),
    '#description' => t('These Gallery2 plugins support much of the functionality that the Drupal Gallery module provides.
                         None of them are strictly required, but you will almost certainly want to activate at least some
                         of them (particularly the Image Block plugin).'),
  );  
     
  // Unwanted (interfering) G2 plugins  
  $unwanted_g2_plugins = gallery_unwanted_plugin_info();
  $rows = array();
  foreach ($unwanted_g2_plugins as $key => $module) {
    // Find the combination of status and severity of the plugin
    $severity = ($module['status'] == GALLERY_PLUGIN_ENABLED) ? 
      $module['severity'] : GALLERY_SEVERITY_SUCCESS;    
    $row = array();
    $row[] = array('data' => $module['title'], 'align' => 'left', 'width' => '15%');
    $row[] = array('data' => theme('gallery_severity_status_message', $severity, $module['status'], TRUE, TRUE), 'align' => 'center');
    $row[] = array('data' => $module['info'], 'class' => 'description', 'id' => 'gallery-install-plugin-'. $key);
    $rows[] = $row;
    if ($module['status'] == GALLERY_PLUGIN_ENABLED && $severity > $overall_plugin_severity) {
      $overall_plugin_severity = $severity;
      $overall_plugin_status = $module['status'];
    }
  }
  $form['plugins']['unwanted_g2_plugins'] = array(
    '#type' => 'fieldset',
    '#title' =>  t('Gallery2 plugins which should not be installed'),
    '#collapsible' => FALSE,
    '#collapsed' => FALSE,
    '#value' => theme('table', $header, $rows, array('class' => 'package')),
    '#description' => t('These Gallery2 plugins should not be used when Gallery2 is
                         embedded into Drupal as they may cause problems.'),
  );  
    
  // Wanted (optional) Drupal modules
  $wanted_modules = gallery_wanted_module_info();
  $rows = array();
  foreach ($wanted_modules as $key => $module) {
    // Find the combination of status and severity of the plugin
    $severity = (!$module['status']) ? $module['severity'] : GALLERY_SEVERITY_SUCCESS;    
    $row = array();
    $row[] = array('data' => $module['title'], 'align' => 'left', 'width' => '15%');
    $row[] = array('data' => theme('gallery_severity_status_message', $severity, $module['status']), 'align' => 'center');
    $row[] = array('data' => $module['info'], 'class' => 'description', 'id' => 'gallery-install-plugin-'. $key);
    $rows[] = $row;
    if ($module['status'] != GALLERY_PLUGIN_ENABLED && $severity > $overall_plugin_severity) {
      $overall_plugin_severity = $severity;
      $overall_plugin_status = $module['status'];
    }
  }
  $form['plugins']['wanted_modules'] = array(
    '#type' => 'fieldset',
    '#title' =>  t('Optional Drupal modules'),
    '#collapsible' => FALSE,
    '#collapsed' => FALSE,
    '#value' => theme('table', $header, $rows, array('class' => 'package')),
    '#description' => t('These Drupal modules can optionally be used to enhance the functionality of the Gallery module.'),
  );

  // Check if no issue was found.
  if ($overall_plugin_severity < GALLERY_SEVERITY_UNKNOWN) {
    $overall_plugin_severity = GALLERY_SEVERITY_SUCCESS;
  }

  $install_status['plugins']['status'] = $overall_plugin_status;
  $install_status['plugins']['severity'] = $overall_plugin_severity;
  
  if ($overall_plugin_status <= 0) {
    // There is a problem with at least one module/plugin
    $form_values['plugins_valid'] = FALSE;   
    $form['plugins']['#title'] .= ' ('. strip_tags(theme('gallery_severity_message', $overall_plugin_severity)) .')';       
    $install_status['plugins']['info'] = t('You may have some loss in functionality in your embedded Gallery2 (see below
                                            for details). You should check the details and if the functionality is not
                                            important for your site you can just ignore this.');
    $form['plugins']['#collapsed'] = !$form_values['initial_check'];
    if ($form_values['initial_check']) {
      $form_values['step']++;
    }
  }
  else {
    $form_values['step']++;
    $form_values['plugins_valid'] = TRUE;
    $form['plugins']['#collapsible'] = TRUE;
    $form['plugins']['#collapsed'] = TRUE;
    $form['plugins']['#title'] .= ' '. t('(OK)');       
    $install_status['plugins']['info'] = t('The status of all Drupal modules and Gallery2 plugins
                                            is optimal for your embedded Gallery2.');
  }
}

/**
 * Function _gallery_install_step_urlrewrite().
 * Step 4: Clean URL configuration
 */
function _gallery_install_step_urlrewrite(&$form, &$form_values, &$install_status) {
  $form['rewrite'] = array('#type' => 'fieldset');
  
  $clean_urls_status = variable_get('clean_url', 0);
  $rewrite_status = gallery_single_plugin_status('rewrite');

  if ($clean_urls_status) {
    if ($rewrite_status == GALLERY_PLUGIN_ENABLED) {
      _gallery_install_urlrewrite($public_path, $htaccess_path, TRUE);
      $public_path = isset($form_values['htaccess_public_path']) ? $form_values['htaccess_public_path'] : $public_path;
      $htaccess_path = isset($form_values['htaccess_filesystem_path']) ? $form_values['htaccess_filesystem_path'] : $htaccess_path;
      // Check for writable .htaccess file
      if (file_exists($htaccess_path .'.htaccess')) {
        if (is_writable($htaccess_path .'.htaccess')) {
          $form_values['rewrite_valid'] = ($form_values['initial_check'] || $form_values['step'] > GALLERY_INSTALL_STEP_URLREWRITE);
          $result = t('There is a writable .htaccess file in your defined Drupal directory (@dir).',
                        array('@dir' => $htaccess_path));
          // Check syntax of the 'Show Item' rule (must start with 'gallery/')
          list ($ret, $rules) = GalleryCoreApi::getPluginParameter('module', 'rewrite', 'activeRules');
          if (!$ret) {
            $rules = unserialize($rules);
            if (isset($rules['rewrite'][0]['pattern']) && substr($rules['rewrite'][0]['pattern'], 0, 7) != 'gallery') {
              $result .= ' <strong>'. t('Your \'Show Item\' rule should start with \'gallery/\'.
                                         Make sure to change the URL Rewrite rule(s) accordingly.') .'</strong>';
            }
          }
        }
        else {
          $form_values['rewrite_valid'] = FALSE;
          $result = t('The .htaccess file in your defined Drupal directory (@dir) is not writable. Please CHMOD it to 644
                       (or 666 if 644 does not work).', array('@dir' => $htaccess_path));
        }
      }
      else {
        $form_values['rewrite_valid'] = FALSE;
        $result = t('There is no .htaccess file in your defined Drupal directory (@dir) or the directory does not exist.',
                      array('@dir' => $htaccess_path));
      }
    }
    else {
      $form_values['rewrite_valid'] = FALSE;
      $result = t('Clean URLs are enabled in Drupal, but the Gallery2 URL Rewrite plugin is unavailable.');
    }
  }
  else {
    $form_values['rewrite_valid'] = TRUE;
    $result = t('Clean URLs are disabled in Drupal and the URL Rewrite plugin will not be configured.');
    $form['rewrite']['#description'] = t('Clean URLs are disabled in Drupal and the URL Rewrite plugin will not be configured.
                                          If you want to use the URL Rewrite plugin please enable clean URLs in Drupal and
                                          install and activate the plugin in Gallery2.');
  }
  
  // User selected to skip the URLRewrite step
  if (variable_get('gallery_rewrite_disable', 0)) {
    $form_values['rewrite_valid'] = TRUE;
    $clean_urls_status = FALSE;
    $result = $form['rewrite']['#description'] = t('URL Rewrite has been disabled manually.');
    $form['rewrite']['#description'] .= ' '. t('\'Reset & Restart\' your configuration to change these settings.');
  }
  
  if ($form_values['rewrite_valid']) {
    $form_values['step']++;
  }
  
  $form['rewrite']['#title'] = t('Step 4: Clean URLs / URL Rewrite settings') . ($form_values['rewrite_valid'] ? ' '. t('(OK)') : '');
  $form['rewrite']['#collapsible'] = ($form_values['step'] > GALLERY_INSTALL_STEP_URLREWRITE);
  $form['rewrite']['#collapsed'] = $form_values['rewrite_valid'];

  if ($clean_urls_status) {
    if ($rewrite_status < GALLERY_PLUGIN_ENABLED) {
      $form['rewrite']['#description'] = t('Clean URLs are enabled in Drupal, but the Gallery2 URL Rewrite plugin is unavailable
                                            (!status).', array('!status' => theme('gallery_plugin_status_message', $rewrite_status)));
      if (!$form_values['initial_check'] && !$form_values['rewrite_valid']) {
        $form_values['step'] = GALLERY_INSTALL_STEP_URLREWRITE;
        $form['rewrite']['check'] = array('#type' => 'submit', '#value' => t('Check URL Rewrite status again'));
      }
    }
    else {
      // CleanURL and URLRewrite are both enabled
      $form['rewrite']['#description'] = t('Clean URLs are !clean_url_status in Drupal and the Gallery2 URL Rewrite plugin is
                                            !rewrite_status. It is possible to automatically configure the URL Rewrite plugin.
                                            The configuration assumes that the rules should be placed in your Drupal .htaccess
                                            file (it will add them to the beginning) which works in most applications. If you
                                            need a special configuration, enter the desired values manually.',
        array(
          '!clean_url_status' => theme('gallery_module_status_message', $clean_urls_status),
          '!rewrite_status' => theme('gallery_plugin_status_message', $rewrite_status)
        )
      );
      $form['rewrite']['#description'] .= $form_values['rewrite_valid'] ? '' : ('<p>'. $result .'</p>');
      
      $form['rewrite']['htaccess_public_path'] = array(
        '#type' => 'textfield',
        '#title' => t('Public path to your .htaccess file'),
        '#size' => 64,
        '#maxlength' => 255,
        '#default_value' => $public_path,
        '#description' => t('This is the location of your Drupal .htaccess file relative to your webserver document root.'),
        '#disabled' => $form_values['rewrite_valid'],
      );
      $form['rewrite']['htaccess_filesystem_path'] = array(
        '#type' => 'textfield',
        '#title' => t('Filesystem path to your .htaccess file'),
        '#size' => 100,
        '#maxlength' => 255,
        '#default_value' => $htaccess_path,
        '#description' => t('This is the absolute directory path of your Drupal .htaccess file.'),
        '#disabled' => $form_values['rewrite_valid'],
      );
      if (!$form_values['initial_check'] && !$form_values['rewrite_valid']) {
        $form['rewrite']['config'] = array('#type' => 'submit', '#value' => t('Configure URL Rewrite plugin'));
      }
    }
    
    if (!$form_values['initial_check'] && !$form_values['rewrite_valid']) {
      $form['rewrite']['skip'] = array('#type' => 'submit', '#value' => t('Skip URL Rewrite Config'));
    }
  }

  $install_status['cleanurls']['status'] = $form_values['rewrite_valid'];
  $install_status['cleanurls']['info'] = $result;
}

/**
 * Function _gallery_install_step_usersync().
 * Step 5: User Synchronization
 */ 
function _gallery_install_step_usersync(&$form, &$form_values, &$install_status) {
  $form_values['gallery_valid'] = variable_get('gallery_valid', 0);
  
  if ($form_values['gallery_valid']) {
    $form_values['step']++;
  }
  
  $form['usersync'] = array(
    '#type' => 'fieldset',
    '#title' => t('Step 5: Initial User Synchronization') . ($form_values['gallery_valid'] ? ' '. t('(OK)') : ''),
    '#collapsible' => ($form_values['step'] > GALLERY_INSTALL_STEP_USERSYNC),
    '#collapsed' => ($form_values['gallery_valid']),
  );
  
  $install_status['usersync']['status'] = $form_values['gallery_valid'];
  if ($form_values['gallery_valid']) {
    $install_status['usersync']['info'] = $form['usersync']['#description'] = t('Your initial user synchronization has been
        completed already.<br />If you want to resync all your users or you want to import users from an existing Gallery2
        setup, you can always use the <a href= "@gallery-usersync">Advanced Sync</a> options in the Gallery user administration.',
        array('@gallery-usersync' => url('admin/user/gallery/advanced')));
  }
  else {
    $install_status['usersync']['info'] = $form['usersync']['#description'] = t('User synchronization is essential for the
        embedded Gallery to work correctly. Drupal users/groups are usually synced with their Gallery counterparts when a
        user/group is modified in Drupal. Missing user mappings will cause errors in your embedded Gallery.');
    $form['usersync']['#description'] .= '<br /><br />'. t('It is recommended that you sync your users now. However there
        can be reasons to skip this step, e.g. if you have a working Gallery with many users and a fresh Drupal installation.
        Note that the current user and the Drupal superuser (uid=1) will always be sync.');
    
    $form['usersync']['sync'] = array('#type' => 'submit', '#value' => t('Sync users/groups'));
    $form['usersync']['skip'] = array('#type' => 'submit', '#value' => t('Skip sync'));
  }
}

/**
 * Function _gallery_install_submit().
 */
function _gallery_install_submit($form_id, $form_values) {
  switch ($form_values['op']) {
    case t('Sync users/groups'):
    case t('Skip sync'):
      $autodetect = variable_get('gallery_autodetect_dir', 1);
      if ($autodetect) {
        variable_set('gallery_uri', $form_values['gallery_uri_auto']);
        variable_set('gallery_dir', $form_values['gallery_dir_auto']);
        variable_set('gallery_embed_uri', $form_values['gallery_embed_uri_auto']);
      }
      else {
        variable_set('gallery_uri', $form_values['gallery_uri_man']);
        variable_set('gallery_dir', $form_values['gallery_dir_man']);
        variable_set('gallery_embed_uri', $form_values['gallery_embed_uri_man']);
      }
      variable_del('gallery_wizard_data');
      
      // This is the last step: gallery_valid will be TRUE even
      // if the admin decides to skip the user/group sync step
      $form_values['gallery_valid'] = TRUE;
      
      // Always sync (at least) the current user to avoid
      // errors (unknown user) during GalleryEmbed::init()
      require_once(drupal_get_path('module', 'gallery') .'/gallery_user.inc');
      global $user;
      gallery_user_modify($user, 'update', TRUE, $form_values);
      // Make sure the Drupal superuser (uid=1) always gets admin access
      if ($user->uid != 1) {
        gallery_user_modify(user_load(array('uid' => 1)), 'update', FALSE, $form_values);
      }
      
      // Set gallery_valid variable and rebuild the menu so that
      // the user sync callback is available for the next step
      variable_set('gallery_valid', $form_values['gallery_valid']);
      // Clear cache and rebuild menu
      cache_clear_all('gallery', 'cache', TRUE);
      menu_rebuild();
      
      // Trigger bulk user/group sync
      if ($form_values['op'] != t('Skip sync')) {
        require_once(drupal_get_path('module', 'gallery') .'/gallery_user_admin.inc');
        _gallery_user_advanced_start(array('sync'), 'admin/settings/gallery/install');
      }
      drupal_get_messages();
      drupal_goto('admin/settings/gallery/install');
      break;
    case t('Use Manual Configuration'):
      variable_set('gallery_autodetect_dir', 0);
      $form_values['step'] = GALLERY_INSTALL_STEP_LOCATIONS;
      break;
    case t('Use Auto Configuration'):
      variable_set('gallery_autodetect_dir', 1);
      $form_values['step'] = GALLERY_INSTALL_STEP_LOCATIONS;
      break;
    case t('Configure URL Rewrite plugin'):
      if (!_gallery_install_urlrewrite($form_values['htaccess_public_path'], $form_values['htaccess_filesystem_path'])) {
        $form_values['step'] = GALLERY_INSTALL_STEP_URLREWRITE;
      }
      break;
    case t('Skip URL Rewrite Config'):
      variable_set('gallery_rewrite_disable', 1);
      break;
    case t('Reset & Restart'):
      // Reset configuration
      variable_del('gallery_autodetect_dir');
      variable_del('gallery_uri');
      variable_del('gallery_dir');
      variable_del('gallery_embed_uri');
      variable_del('gallery_valid');
      variable_del('gallery_rewrite_disable');
      variable_del('gallery_wizard_data');
      menu_rebuild();
      variable_set('gallery_config_reset', TRUE);
      drupal_get_messages();
      drupal_goto('admin/settings/gallery/install');
      break;
  }
  
  variable_set('gallery_wizard_data', serialize($form_values));
}

/**
 * Function _gallery_install_locations().
 */
function _gallery_install_locations(&$form, &$form_values, &$install_status) {
  include_once(drupal_get_path('module', 'gallery') .'/G2EmbedDiscoveryUtilities.class');

  $autodetect = variable_get('gallery_autodetect_dir', 1);
  if ($form_values['initial_check']) {
    $orig_values['g2_uri'] = variable_get('gallery_uri', '/gallery2/');
    $orig_values['g2_embed_path'] = variable_get('gallery_dir', './gallery2/');
    $orig_values['embed_uri'] = variable_get('gallery_embed_uri', '?q=gallery');
  }
  else {
    if ($autodetect) {
      $orig_values['g2_uri'] = $form_values['gallery_uri_auto'];
    }
    else {
      $orig_values['g2_uri'] = $form_values['gallery_uri_man'];
      $orig_values['g2_embed_path'] = $form_values['gallery_dir_man'];
      $orig_values['embed_uri'] = $form_values['gallery_embed_uri_man'];
    }
  }

  list($gallery_valid, $detect_values, $result) = _gallery_install_locations_check($orig_values, $autodetect);
  if (!$gallery_valid) {
    $form['install']['#description'] = gallery_format_status($result, t('Errors in your current Gallery2 location settings:'));
  }

  if ($autodetect) {
    $form_values['gallery_uri_auto'] = $detect_values['g2_uri'];
    $form_values['gallery_dir_auto'] = $detect_values['g2_embed_path'];
    $form_values['gallery_embed_uri_auto'] = $detect_values['embed_uri'];
  }
  else {
    $form_values['gallery_uri_man'] = $detect_values['g2_uri'];
    $form_values['gallery_dir_man'] = $detect_values['g2_embed_path'];
    $form_values['gallery_embed_uri_man'] = $detect_values['embed_uri'];
  }
  $form_values['gallery_valid'] = $gallery_valid;

  $install_status['locations']['status'] = $gallery_valid;
  $install_status['locations']['info'] = $gallery_valid ?
    t('The Gallery2 location settings appear to be correct.') :
    t('There is a problem with the Gallery2 location settings. Please check below and retest.
       Remember that the auto-config will not work for all hosts.');
}

/**
 * Function _gallery_install_locations_check().
 */
function _gallery_install_locations_check($orig, $autodetect) {
  // Set up the result status array. The rest gets filled in later.
  $result = array(
    'g2_uri' => array(
          'title' => t('URI of Gallery2'),
          'severity' => GALLERY_SEVERITY_ERROR,
    ),
    'g2_embed_path' => array(
          'title' => t('Location of Gallery2'),
          'severity' => GALLERY_SEVERITY_ERROR,
    ),
    'init' => array(
          'title' => t('Gallery Init'),
          'severity' => GALLERY_SEVERITY_ERROR,
    ),
  );
  
  $vars = array();
  $vars['gallery_valid'] = TRUE;
  
  // Strip the end /gallery if present and replace with index.php?q=gallery to avoid any 
  // url rewrite issues. See http://gallery.menalto.com/node/46181
  // Note the use of index.php in all cases. Not needed for Apache, but for IIS
  
  $embed_uri = $orig['embed_uri'];
  if ($autodetect || empty($embed_uri)) {
    $embed_uri = url('gallery', NULL, NULL, FALSE);
    // i18n overrides the link to gallery to include a ?q=en or something
    if (module_exists('i18n')) {
      i18n_get_lang_prefix($embed_uri, TRUE);
    }
    if (substr($embed_uri, -8) == '/gallery') {
      $embed_uri = substr($embed_uri, 0, -7) .'index.php?q=gallery';
    }
  }
  
  // Normalise the Embed Application URI
  $embed_uri = G2EmbedDiscoveryUtilities::normalizeEmbedUri($embed_uri); 
  $vars['embed_uri'] = $embed_uri;     
     
  // Normalise the G2 URI
  $g2_uri = G2EmbedDiscoveryUtilities::normalizeG2Uri($orig['g2_uri']);
  $vars['g2_uri'] = $g2_uri;

    // Find the Gallery Directory and Embed URI
  if ($autodetect) {
    // Auto-Detect the G2 embed path 
    list($success, $embed_php_path, $error_string) = 
      G2EmbedDiscoveryUtilities::getG2EmbedPathByG2Uri($g2_uri); 
    if ($success) {
      // G2 Embed Path is found OK
      $vars['g2_embed_path'] = rtrim($embed_php_path, 'embed.php'); 
    }
    else {
      // Something is wrong with the G2 URI given as the G2 embed path is not found
      // Try getG2EmbedPathByG2UriEmbedUriAndLocation instead
      $drupal_path = realpath(".") .'/';  
      list($success, $embed_php_path, $error_string) =
        G2EmbedDiscoveryUtilities::getG2EmbedPathByG2UriEmbedUriAndLocation($g2_uri, $embed_uri, $drupal_path);
      if ($success) {
        // G2 Embed Path is found OK
        $vars['g2_embed_path'] = rtrim($embed_php_path, 'embed.php'); 
      }
      else {
        $result['g2_uri']['status'] = FALSE;
        $result['g2_uri']['info'] = $error_string;
        $vars['g2_embed_path'] = '';
        $vars['gallery_valid'] = FALSE;
      } 
    }
    // Check for config.php in the embed_path (not existing => invalid path)
    //  e.g. this is the path to the G2 codebase, but we have a multisite configuration
    if (!empty($vars['g2_embed_path'])) {
      list($ok, $error_string) = G2EmbedDiscoveryUtilities::isFileReadable($vars['g2_embed_path'] .'config.php');
      if (!$ok) {
        $result['g2_embed_path']['status'] = FALSE;
        $result['g2_embed_path']['info'] = $error_string;
        $vars['g2_embed_path'] = '';
        $vars['gallery_valid'] = FALSE;
      }
    }
  } 
  else {
    // Do not autodetect the variables, but check the manually entered ones.
    $embed_php_path = $orig['g2_embed_path'];
    $embed_php_path .= (substr($embed_php_path, -1) != '/') ? '/' : '';
    // Check path can be read, adding embed.php if needed
    list($ok, $error_string) = G2EmbedDiscoveryUtilities::isFileReadable($embed_php_path .'embed.php');
    $vars['g2_embed_path'] = $embed_php_path;
    if (!$ok) {
      $result['g2_embed_path']['status'] = FALSE;
      $result['g2_embed_path']['info'] = $error_string;
      $vars['gallery_valid'] = FALSE;
    }
    else {
      // Check for config.php in the embed_path (not existing => invalid path)
      //  e.g. this is the path to the G2 codebase, but we have a multisite configuration
      list($ok, $error_string) = G2EmbedDiscoveryUtilities::isFileReadable($embed_php_path .'config.php');
      if (!$ok) {
        $result['g2_embed_path']['status'] = FALSE;
        $result['g2_embed_path']['info'] = $error_string;
        $vars['gallery_valid'] = FALSE;
      }
    }
  }
  
  // If the filepaths seem correct then check Gallery2 works and has the correct module configs
  if ($vars['gallery_valid']) {
    // Gallery install is thought valid, so init it.
    $vars['gallery_dir'] = $vars['g2_embed_path'];
    if (!_gallery_init(TRUE, $vars, FALSE)) {
      // Gallery install was supposed to be valid, but it still failed. Something is wrong.
      $result['init']['status'] = FALSE;
      $result['init']['info'] = t('Everything seemed OK, but the Gallery could still not be initialised.
                                   Perhaps a manually entered value is incorrect.');
      $vars['gallery_valid'] = FALSE;
    }
    else {
      // Is Gallery2 installed inside the Drupal root directory?
      _gallery_install_in_drupal_folder($vars['g2_embed_path']);
      // Update version info
      gallery_version();       
      GalleryEmbed::done();
    }
  }

  // Only return items where status has been set
  foreach ($result as $key => $value) {
    if (!isset($value['status'])) {
      unset($result[$key]);
    }
  }
  
  return array($vars['gallery_valid'], $vars, $result);
}

/**
 * Function _gallery_install_in_drupal_folder().
 */
function _gallery_install_in_drupal_folder($embed_path) {
  global $base_url;
  static $warn = TRUE;
  
  // Dont proceed if G2 was not initialized
  if (!isset($GLOBALS['gallery'])) {
    return;
  }
  
  if (!empty($embed_path)) {
    // Reset 'gallery_outside' state
    variable_del('gallery_outside');
    // Get location of Drupal, Gallery2, etc.
    $docroot = strtolower(str_replace('/', '\\' , $_SERVER['DOCUMENT_ROOT']));
    $base_path = strtolower(str_replace('/', '\\' , base_path()));
    $g2_base = strtolower($GLOBALS['gallery']->getConfig('galleryBaseUrl'));
    if ((strpos(strtolower($embed_path), $base_path) === FALSE && strpos(strtolower($embed_path), $docroot) !== FALSE)
        || (!empty($g2_base) && strpos($g2_base, $base_url) === FALSE) || strpos(strtolower($embed_path), '../') !== FALSE) {
      // G2 is installed outside the Drupal root directory
      variable_set('gallery_outside', TRUE);
      if ($warn) {
        // Avoid duplicate warning
        $warn = FALSE;
        drupal_set_message(t('Your location settings are valid, but your Gallery2 is installed outside the Drupal
                              root directory. It is highly advisable to move G2 into the Drupal folder or to create
                              a symbolic link in the Drupal directory pointing to your G2 installation (see
                              instructions on <a href="@codex">codex.gallery2.org</a>).',
                              array('@codex' => url('http://codex.gallery2.org/Integration:Drupal:Installation'))), 'error');
      }
    }
  }
}

/**
 * Function _gallery_install_urlrewrite().
 */
function _gallery_install_urlrewrite(&$public_path, &$htaccess_path, $load_config = FALSE) {
  list($ret, $rewrite_api) = GalleryCoreApi::newFactoryInstance('RewriteApi');
  if ($ret || !isset($rewrite_api)) {
    gallery_error(t('Error trying to create URL Rewrite plugin instance.'), $ret);
    if (!$ret) {
      drupal_set_message(t('URL Rewrite plugin could not be instantiated.
                            Please check its configuration in standalone Gallery2.'), 'error');
    }
    return FALSE;
  }
  
  list($ret, $params) = $rewrite_api->fetchEmbedConfig();
  if ($ret) {
    gallery_error(t('Error trying to fetch Embedded URL Rewrite configuration.'), $ret);
    return FALSE;
  }
  
  // Load the configuration from G2 (or derive from Drupal path)
  if ($load_config) {
    if (empty($params['embeddedHtaccess'])) {
      $http = 'http'. (isset($_SERVER['HTTPS']) ? (($_SERVER['HTTPS'] == 'on') ? 's' : '') : '');
      $public_path = str_replace($http .'://'. $_SERVER['HTTP_HOST'], '', base_path());
      $htaccess_path = realpath(".") .'/';
    }
    else {
      $public_path = $params['embeddedLocation'];
      $htaccess_path = $params['embeddedHtaccess'];
    }
  }
  
  // Check for trailing slash
  $public_path .= (substr($public_path, -1) != '/') ? '/' : '';
  $htaccess_path .= (substr($htaccess_path, -1) != '/') ? '/' : '';
  
  if (!$load_config) {
    if (!file_exists($htaccess_path .'.htaccess')) {
      // File .htaccess does not exist
      if (is_writable($htaccess_path .'.htaccess')) {
        // Directory exists and is writable => try to create .htaccess
        $f = fopen($htaccess_path .'.htaccess', 'w');
        fclose($f);
      }
      else {
        return FALSE;
      }
    }
    // Save the G2 rewrite values
    $params['embeddedLocation'] = $public_path;
    $params['embeddedHtaccess'] = $htaccess_path;
    list($ret, $code, $errstr) = $rewrite_api->saveEmbedConfig($params);
    if ($ret) {
      gallery_error(t('Error trying to save Embedded URL Rewrite configuration.'), $ret);
      return FALSE;
    }
    if ($code) {
      $errstr =  $code .' - '. (is_array($errstr) ? $errstr[1] : $errstr);
      drupal_set_message(t('The Gallery2 URL Rewrite plugin returned the following error:') .'<br /><pre>'. $errstr .'</pre>', 'error');
      return FALSE;
    }
  }
  
  return TRUE;
}