Return suggestions only for the first word in a comment line

As apiDoc tags are first words in comment lines, it is useless to provide apiDoc
auto completion suggestions in the middle of the line. So, now apiDoc suggestions
are provided only for the first word in a comment line.

Author: DWand

apiDocAutocompletion.py

@@ -5,9 +5,25 @@
 
 import sublime
 import sublime_plugin
+import re
 
 SETTINGS_FILENAME = 'apiDocAutocompletion.sublime-settings'
 
+
+def is_line_start(view, location):
+    """
+    Determines whether the given location is situated on beginning of the comment line
+    Returns:
+        bool: True if the location is situated in the beginning of the comment line,
+              False otherwise
+    """
+    word_bounds = view.word(location)
+    line_bounds = view.line(location)
+    prefix_bounds = sublime.Region(line_bounds.begin(), word_bounds.begin())
+    prefix = view.substr(prefix_bounds)
+    return re.search('\w', prefix) == None
+
+
 class apiDocAutocompletion(sublime_plugin.EventListener):
     _suggestions = [
         ("@api\tapiDoc", "@api {${1:method}} ${2:path} ${3:[title]}"),
@@ -91,6 +107,7 @@ def on_query_completions(self, view, prefix, locations):
         current_scope = view.scope_name(location)
 
         if any(scope in current_scope for scope in target_scopes) == True:
-            return apiDocAutocompletion._suggestions
-        else:
-            return None
+            if is_line_start(view, location):
+                return apiDocAutocompletion._suggestions
+
+        return None