feat: Add --new flag to UI with prefill options for title, template, participants, context

Opens new discussion dialog on launch with optional pre-filled values.
Enables integration with development-hub for launching discussions from todos.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/discussions/cli.py

@@ -372,6 +372,15 @@ def cmd_ui(args) -> int:
         else:
             directory = path
 
+    # Parse prefill options
+    show_new = getattr(args, 'new', False)
+    prefill_title = getattr(args, 'title', None)
+    prefill_template = getattr(args, 'template', None)
+    prefill_context = getattr(args, 'context', None)
+    prefill_participants = None
+    if getattr(args, 'participants', None):
+        prefill_participants = [p.strip().lstrip('@') for p in args.participants.split(',')]
+
     if args.tui:
         # Launch TUI (urwid-based)
         try:
@@ -380,6 +389,7 @@ def cmd_ui(args) -> int:
             print("Error: TUI requires urwid. Install with: pip install urwid")
             print(f"Details: {e}")
             return 1
+        # TUI doesn't support --new yet, just launch normally
         tui_main(directory, open_file=open_file)
     else:
         # Launch GUI (Dear PyGui-based)
@@ -395,7 +405,15 @@ def cmd_ui(args) -> int:
                 print(f"TUI also unavailable: {e2}")
                 return 1
             return 0
-        gui_main(directory, open_file=open_file)
+        gui_main(
+            directory,
+            open_file=open_file,
+            show_new_dialog=show_new,
+            prefill_title=prefill_title,
+            prefill_template=prefill_template,
+            prefill_participants=prefill_participants,
+            prefill_context=prefill_context,
+        )
     return 0
 
 
@@ -461,6 +479,11 @@ def main(argv: list[str] = None) -> int:
     p_ui = subparsers.add_parser("ui", help="Launch interactive UI")
     p_ui.add_argument("path", nargs="?", help="Discussion file (.md) or directory to browse")
     p_ui.add_argument("--tui", action="store_true", help="Use terminal UI instead of graphical UI")
+    p_ui.add_argument("--new", "-n", action="store_true", help="Open new discussion dialog on launch")
+    p_ui.add_argument("--title", help="Pre-fill title in new discussion dialog (requires --new)")
+    p_ui.add_argument("--template", help="Pre-select template in new discussion dialog (requires --new)")
+    p_ui.add_argument("--participants", help="Pre-select participants, comma-separated (requires --new)")
+    p_ui.add_argument("--context", help="Pre-fill context/description in new discussion dialog (requires --new)")
     p_ui.set_defaults(func=cmd_ui)
 
     args = parser.parse_args(argv)

src/discussions/ui/gui.py

@@ -2454,8 +2454,16 @@ class DiscussionGUI:
             ("pragmatist", "AI-Pragmatist")
         ]
 
-    def _show_new_discussion_dialog(self):
+    def _show_new_discussion_dialog(self, prefill_title: str = None, prefill_template: str = None,
-        """Show dialog for creating a new discussion."""
+                                       prefill_participants: list[str] = None, prefill_context: str = None):
+        """Show dialog for creating a new discussion.
+
+        Args:
+            prefill_title: Pre-fill title field
+            prefill_template: Pre-select template
+            prefill_participants: Pre-select participants (list of aliases)
+            prefill_context: Pre-fill context/description field
+        """
         window_tag = "new_discussion_dialog"
         if dpg.does_item_exist(window_tag):
             dpg.delete_item(window_tag)
@@ -2463,9 +2471,10 @@ class DiscussionGUI:
         templates = self._get_templates()
         participants = self._get_participants()
 
-        # State for the dialog
+        # State for the dialog - use prefill if provided, otherwise defaults
+        default_participants = prefill_participants if prefill_participants else ["architect", "security", "pragmatist"]
         dialog_state = {
-            'selected_participants': ["architect", "security", "pragmatist"],
+            'selected_participants': list(default_participants),
         }
 
         def toggle_participant(sender, app_data, user_data):
@@ -2545,7 +2554,8 @@ class DiscussionGUI:
                        width=550, height=550, pos=[400, 150], no_collapse=True):
 
             dpg.add_text("Title:", color=(150, 200, 255))
-            dpg.add_input_text(tag="new_disc_title", width=-1, hint="Enter discussion title")
+            dpg.add_input_text(tag="new_disc_title", width=-1, hint="Enter discussion title",
+                              default_value=prefill_title or "")
 
             dpg.add_spacer(height=5)
             dpg.add_text("Location:", color=(150, 200, 255))
@@ -2561,10 +2571,15 @@ class DiscussionGUI:
             dpg.add_spacer(height=10)
             dpg.add_text("Template:", color=(150, 200, 255))
             template_items = templates + ["+ Create New Template..."]
+            # Use prefill template if valid, otherwise first template or 'feature'
+            if prefill_template and prefill_template in templates:
+                default_template = prefill_template
+            else:
+                default_template = templates[0] if templates else "feature"
             dpg.add_combo(
                 items=template_items,
                 tag="new_disc_template",
-                default_value=templates[0] if templates else "feature",
+                default_value=default_template,
                 width=-1,
                 callback=on_template_change
             )
@@ -2582,10 +2597,10 @@ class DiscussionGUI:
 
             with dpg.child_window(height=150, border=True):
                 for alias, display_name in participants:
-                    is_default = alias in ["architect", "security", "pragmatist"]
+                    is_selected = alias in dialog_state['selected_participants']
                     dpg.add_checkbox(
                         label=f"@{alias} ({display_name})",
-                        default_value=is_default,
+                        default_value=is_selected,
                         callback=toggle_participant,
                         user_data=alias
                     )
@@ -2597,7 +2612,8 @@ class DiscussionGUI:
                 multiline=True,
                 width=-1,
                 height=100,
-                hint="Describe what this discussion is about..."
+                hint="Describe what this discussion is about...",
+                default_value=prefill_context or ""
             )
 
             dpg.add_spacer(height=15)
@@ -4139,6 +4155,17 @@ final = json.dumps(parsed)''',
             self._open_discussion(self._pending_open_file)
             self._pending_open_file = None
 
+        # Show new discussion dialog if requested
+        if getattr(self, '_pending_new_dialog', None):
+            prefill = self._pending_new_dialog
+            self._show_new_discussion_dialog(
+                prefill_title=prefill.get('title'),
+                prefill_template=prefill.get('template'),
+                prefill_participants=prefill.get('participants'),
+                prefill_context=prefill.get('context'),
+            )
+            self._pending_new_dialog = None
+
         # Manual render loop with background task polling
         while dpg.is_dearpygui_running():
             # Poll for updates from background threads (output, turn completion)
@@ -4150,12 +4177,19 @@ final = json.dumps(parsed)''',
         dpg.destroy_context()
 
 
-def main(discussions_dir: str = None, open_file: str = None):
+def main(discussions_dir: str = None, open_file: str = None, show_new_dialog: bool = False,
+         prefill_title: str = None, prefill_template: str = None,
+         prefill_participants: list[str] = None, prefill_context: str = None):
     """Entry point for GUI.
 
     Args:
         discussions_dir: Directory to browse for discussions
         open_file: Specific discussion file to open immediately
+        show_new_dialog: Show new discussion dialog on launch
+        prefill_title: Pre-fill title in new discussion dialog
+        prefill_template: Pre-select template in new discussion dialog
+        prefill_participants: Pre-select participants in new discussion dialog
+        prefill_context: Pre-fill context in new discussion dialog
     """
     dir_path = Path(discussions_dir) if discussions_dir else None
     app = DiscussionGUI(dir_path)
@@ -4166,6 +4200,17 @@ def main(discussions_dir: str = None, open_file: str = None):
     else:
         app._pending_open_file = None
 
+    # If new dialog was requested, store prefill data
+    if show_new_dialog:
+        app._pending_new_dialog = {
+            'title': prefill_title,
+            'template': prefill_template,
+            'participants': prefill_participants,
+            'context': prefill_context,
+        }
+    else:
+        app._pending_new_dialog = None
+
     app.run()