Dependencies on comments settings?

The main problem with comment form is UX mess - you have to have the comment form at the bottom of comments list otherwise everything does not work! So there's no ability to use other values except COMMENT_FORM_BELOW

The proper ways to fix it is allow loading form for reply links and node link "Add new comment" and not depend of visibility of comment form. Also module should cares about existing comment form on the page but not the current way.

About $cid I mean that ajax_comments_reply() checks for reply in

  // If there is a cid this is a reply to a comment.
  if ($cid) {
    $edit = $edit + array('pid' => $cid);
  }

but all other code ignores it, suppose, this $cid is always none-empty because this function is called for reply link so CID is always has value

Great!

+++ b/ajax_comments.moduleundefined
@@ -296,7 +329,7 @@ function ajax_comments_reply($nid, $cid) {
+  if ($node->comment == COMMENT_NODE_OPEN) {
     $form_build = drupal_get_form("comment_node_{$node->type}_form", (object) $edit);    
     $form = drupal_render($form_build);
   }
@@ -305,7 +338,11 @@ function ajax_comments_reply($nid, $cid) {

@@ -305,7 +338,11 @@ function ajax_comments_reply($nid, $cid) {
   $commands[] = ajax_command_invoke('[id^=comment-wrapper-] form.comment-form', 'remove');
     
   // Add the new form
-  $commands[] = ajax_command_after('#comment-wrapper-' . $cid . ' >.comment', $form);
+  if ($cid) {
+    $commands[] = ajax_command_after('#comment-wrapper-' . $cid . ' >.comment', $form);
+  } else {    ¶
+    $commands[] = ajax_command_append('#comment-wrapper', $form);
+  }

last else should be elsif (isset($form)) {
because we need sure that comments open or admin (UID=1)

1278186-ajax-comment-form.patch

This patch fixes hook_menu to mimic more closely comment.module

Also optimizes loading entities by menu. Suppose ajax_comments_reply() should have more checks like http://dgo.to/a/comment_reply does

PS: sorry fro fuzz in patch, current code has a lot of trailing whitespace,

1278186-whitespace.patch cleans up a whitespace problems

1278186-interdiff.txt - contains only changes of code

Please take a look at 1278186-interdiff.txt I think return nothing is not a good idea but it works

Also what are you thinking about code-style? suppose module should pass Coder module review

I think user should get access denied, probably standard message. Currently users are confused by no-reaction from clicking a link

Make sense to split access thing into other issue except hook_menu()

1278186-interdiff.txt

+++ b/ajax_comments.moduleundefined
@@ -13,18 +13,18 @@
-  $items['ajax_comments/edit/%'] = array(
+  $items['ajax_comments/edit/%comment'] = array(
     'page callback' => 'ajax_comments_edit',
-    'access callback' => 'user_access',
-    'access arguments' => array('edit own comments'),
+    'access callback' => 'comment_access',

This part should be in patch

+++ b/ajax_comments.moduleundefined
@@ -316,19 +352,18 @@ function ajax_comments_reply($nid, $cid) {
 function ajax_comments_edit($cid) {
-  global $base_path;
-  global $user;
-  
-  // Load comment and related node  
   $comment = comment_load($cid);
-  $node = node_load($comment->nid);
-  if ( ( (user_access('edit own comments') && $comment->uid == $user->uid ) || user_access('administer comments') )
-      && $node->comment == COMMENT_NODE_OPEN
-      && (variable_get('comment_form_location_' . $node->type, COMMENT_FORM_BELOW) == COMMENT_FORM_BELOW)) {
-    $form_build = drupal_get_form("comment_node_{$node->type}_form", $comment);
-    $form = drupal_render($form_build);
+  ¶
+  if (!$comment) {
+    return;
   }

Why not just use %comment as menu wildcard as core's comment module does?

+++ b/ajax_comments.moduleundefined
@@ -316,19 +352,18 @@ function ajax_comments_reply($nid, $cid) {
+    ¶

Can you setup your editor to remove trailing whitespaces?

OK, but a bit of clean-up should be done in this issue

+++ b/ajax_comments.moduleundefined
@@ -13,11 +13,11 @@ function ajax_comments_init() {
-  $items['ajax_comments/reply/%/%'] = array(
+  $items['ajax_comments/reply/%'] = array(
     'page callback' => 'ajax_comments_reply',

This change should be reflected in ajax_comments_reply()

They should be $node (node object) and $pid = NULL (like core's comment)

Great! It works and code is much cleaner for now!

let's commit this one (#20) and proceed with white-space clean-up at #1286126: Cleanup code and respect code-style

Great! Now code looks more clean and sane, thanx for taking maintainership