Drupal 7 port of Region Visibility

Also, here is an alternative, based off core Drupal 7 block code. It has no dependencies and comes in at a mere 200 lines of code. Maybe 300 after some UI improvements, 400 with some more comments.

The module that I implemented this in was iwd, for the 3 hooks used.

hook_form_block_admin_display_form_alter() makes the region title a link in the list regions / blocks page.
hook_block_list_alter() removes the blocks on the list before they are rendered.

function iwd_menu() {
  $items['admin/structure/block/regions/%/%'] = array(
    'title' => 'Region visibility',
    'page arguments' => array('region_visibility_form', 4,5),
    'page callback' => 'drupal_get_form',
    'type' => MENU_VISIBLE_IN_BREADCRUMB,
    'access arguments' => array('administer blocks'),
  );

  return $items;
}

function iwd_form_block_admin_display_form_alter(&$form, $form_state) {
  $current_theme = $form['edited_theme']['#value'];
  if (empty($current_theme)) {
    return;
  }
  foreach ($form['block_regions']['#value'] as $key => $title) {
    $settings = region_visibility_theme_settings($current_theme, $key);
    $title = l($title, 'admin/structure/block/regions/' . $current_theme . '/' . $key, array('html' => TRUE));
    if (!empty($settings['roles']) && !empty($settings['pages'])) {
      $title = t('!title - <em>restricted by user role and to certain pages</em>.', array('!title' => $title));
    }
    elseif (!empty($settings['roles'])) {
      $title = t('!title - <em>restricted by user role</em>.', array('!title' => $title));
    }
    elseif (!empty($settings['pages'])) {
      $title = t('!title - <em>restricted to certain pages</em>.', array('!title' => $title));
    }
    $form['block_regions']['#value'][$key] = $title;
  }
}

function iwd_block_list_alter(&$blocks) {
  global $user, $theme_key;
  foreach ($blocks as $key => $block) {
    if (!isset($block->theme) || $block->theme != $theme_key) {
      continue;
    }

    $settings = region_visibility_theme_settings($block->theme, $block->region);

    // If a block has no roles associated, it is displayed for every role.
    if (!empty($settings['roles']) && !array_intersect($settings['roles'], array_keys($user->roles))) {
      unset($blocks[$key]);
      continue;
    }

    // Match path if necessary.
    if ($settings['pages']) {
      $pages = drupal_strtolower($settings['pages']);
      if ($block->visibility < BLOCK_VISIBILITY_PHP) {
        $path = drupal_strtolower(drupal_get_path_alias($_GET['q']));
        $page_match = drupal_match_path($path, $pages);
        if ($path != $_GET['q']) {
          $page_match = $page_match || drupal_match_path($_GET['q'], $pages);
        }
        $page_match = !($block->visibility xor $page_match);
      }
      elseif (module_exists('php')) {
        $page_match = php_eval($settings['pages']);
      }
      else {
        $page_match = FALSE;
      }
    }
    else {
      $page_match = TRUE;
    }
    if (!$page_match) {
      unset($blocks[$key]);
    }
  }
}

function region_visibility_theme_settings($theme, $region = NULL) {
  static $settings = array();
  if (!isset($settings[$theme])) {
    $settings[$theme] = variable_get('region_visibility_' . $theme, array());
  };
  if ($region != NULL) {
    if (!isset($settings[$theme][$region])) {
      $settings[$theme][$region] = array(
        'pages' => '',
        'visibility' => BLOCK_VISIBILITY_NOTLISTED,
        'roles' => array(),
      );
    }
    $settings[$theme][$region]['roles'] = array_filter($settings[$theme][$region]['roles']);
    return $settings[$theme][$region];
  }
  return $settings[$theme];
}

function region_visibility_form($form, $form_state, $theme, $region) {
  $settings = variable_get('region_visibility_' . $theme, array());
  $settings += array($region => array(
    'pages' => '',
    'visibility' => BLOCK_VISIBILITY_NOTLISTED,
    'roles' => array(),
  ));

  $form['#settings'] = $settings;
  $form['#theme'] = $theme;
  $form['#region'] = $region;

  $form['visibility'] = array(
    '#type' => 'vertical_tabs',
    '#attached' => array(
      'js' => array(drupal_get_path('module', 'block') . '/block.js'),
    ),
  );

  // Per-path visibility.
  $form['visibility']['path'] = array(
    '#type' => 'fieldset',
    '#title' => t('Pages'),
    '#collapsible' => TRUE,
    '#collapsed' => TRUE,
    '#group' => 'visibility',
    '#weight' => 0,
  );

  $access = user_access('use PHP for settings');
  if (isset($settings[$region]['visibility']) && $settings[$region]['visibility'] == BLOCK_VISIBILITY_PHP && !$access) {
    $form['visibility']['path']['visibility'] = array(
      '#type' => 'value',
      '#value' => BLOCK_VISIBILITY_PHP,
    );
    $form['visibility']['path']['pages'] = array(
      '#type' => 'value',
      '#value' => isset($settings[$region]['pages']) ? $settings[$region]['pages'] : '',
    );
  }
  else {
    $options = array(
      BLOCK_VISIBILITY_NOTLISTED => t('All pages except those listed'),
      BLOCK_VISIBILITY_LISTED => t('Only the listed pages'),
    );
    $description = t("Specify pages by using their paths. Enter one path per line. The '*' character is a wildcard. Example paths are %blog for the blog page and %blog-wildcard for every personal blog. %front is the front page.", array('%blog' => 'blog', '%blog-wildcard' => 'blog/*', '%front' => '<front>'));

    if (module_exists('php') && $access) {
      $options += array(BLOCK_VISIBILITY_PHP => t('Pages on which this PHP code returns TRUE (experts only)'));
      $title = t('Pages or PHP code');
      $description .= ' ' . t('If the PHP option is chosen, enter PHP code between %php. Note that executing incorrect PHP code can break your Drupal site.', array('%php' => '< ?php ? >'));
    }
    else {
      $title = t('Pages');
    }
    $form['visibility']['path']['visibility'] = array(
      '#type' => 'radios',
      '#title' => t('Show block on specific pages'),
      '#options' => $options,
      '#default_value' => isset($settings[$region]['visibility']) ? $settings[$region]['visibility'] : BLOCK_VISIBILITY_NOTLISTED,
    );
    $form['visibility']['path']['pages'] = array(
      '#type' => 'textarea',
      '#title' => '<span class="element-invisible">' . $title . '</span>',
      '#default_value' => isset($settings[$region]['pages']) ? $settings[$region]['pages'] : '',
      '#description' => $description,
    );
  }

  // Per-role visibility.
  $role_options = array_map('check_plain', user_roles());
  $form['visibility']['role'] = array(
    '#type' => 'fieldset',
    '#title' => t('Roles'),
    '#collapsible' => TRUE,
    '#collapsed' => TRUE,
    '#group' => 'visibility',
    '#weight' => 10,
  );
  $form['visibility']['role']['roles'] = array(
    '#type' => 'checkboxes',
    '#title' => t('Show block for specific roles'),
    '#default_value' => $settings[$region]['roles'],
    '#options' => $role_options,
    '#description' => t('Show this block only for the selected role(s). If you select no roles, the block will be visible to all users.'),
  );

  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Submit'),
  );
  return $form;
}

I would have really thought that this module would have a higher rate of usage. Dropping the dependency may help it usage stats.

Removing myself from the task.

The d6 to d7 upgrades were like small molehills in comparison to the d7 to d8 upgrades that are looking like huge mountains at this point in time, so my other projects will be getting all of my free time.

@klonos - the dependency was dropped as I personally saw no reason for it, although q0rban may object to this. I have always hated enabling 2 modules for this functionality. I must admit that I usually just manually nuke regions in code as required now, meaning zero additional modules ;)