Nicer messages on /contact when there are no contact form categories

Ok, I understand the issue there, but the patch needs work.

contact_mail_page() is not a page callback but a form function. We should not exit() from there. My suggestion is to display a slightly different message if the user doesn't have the administer site-wide contact form permission. For example:

The contact form has not been configured by the administrator.

Revised patch:
1. If there are no categories:
1a. and the current user has the 'administer site-wide contact form' permission, will show a blank page with the message "'The contact form has not been configured. Add one or more categories to the form." (with link to add a category)
1b. otherwise, return drupal_not_found(), or a 404 error. This will help search engines to not index this page when it is not ready.
2. Cleans up some of the code in the site-wide contact form:

-  $result = db_select('contact')
-    ->fields('contact', array('cid', 'category', 'selected'))
-    ->orderby('weight')
-    ->orderby('category')
-    ->execute();
-
-  foreach ($result as $record) {
-    $categories[$record->cid] = $record->category;
-    if ($record->selected) {
-      $default_category = $record->cid;
-    }
-  }
+  $categories = db_query("SELECT cid, category FROM {contact} ORDER BY weight, category")->fetchAllKeyed();
+  $default_category = db_query("SELECT cid FROM {contact} WHERE selected = 1")->fetchField();

-    if (count($categories) > 1) {
-      // If there is more than one category available and no default category has been selected,
-      // prepend a default placeholder value.
-      if (!isset($default_category)) {
-        $default_category = t('- Please choose -');
-        $categories = array($default_category) + $categories;
-      }
-      $form['cid'] = array('#type' => 'select',
-        '#title' => t('Category'),
-        '#default_value' => $default_category,
-        '#options' => $categories,
-        '#required' => TRUE,
-      );
-    }
-    else {
-      // If there is only one category, store its cid.
-      $category_keys = array_keys($categories);
-      $form['cid'] = array('#type' => 'value',
-        '#value' => array_shift($category_keys),
-      );
-    }
+  // If there is more than one category available and no default category has been selected,
+  // prepend a default placeholder value.
+  if (!$default_category) {
+    if (count($categories) > 1) {
+      $categories = array(0 => t('- Please choose -')) + $categories;
+    }
+    else {
+      $default_category = key($categories);
+    }
+  }
+  $form['cid'] = array(
+    '#type' => 'select',
+    '#title' => t('Category'),
+    '#default_value' => $default_category,
+    '#options' => $categories,
+    '#required' => TRUE,
+    '#access' => count($categories) > 1,
+  );

-    // We do not allow anonymous users to send themselves a copy
-    // because it can be abused to spam people.
-    if ($user->uid) {
-      $form['copy'] = array('#type' => 'checkbox',
-        '#title' => t('Send yourself a copy.'),
-      );
-    }
-    else {
-      $form['copy'] = array('#type' => 'value', '#value' => FALSE);
-    }
+  // We do not allow anonymous users to send themselves a copy
+  // because it can be abused to spam people.
+  $form['copy'] = array(
+    '#type' => 'checkbox',
+    '#title' => t('Send yourself a copy.'),
+    '#access' => $user->uid,
+  );

Those are the only changes in the form code, and it really helps simplify the code while keeping the original functionality.

This one should pass all the tests.

Committed to CVS HEAD. Thanks.