feat: implement fine-tune state and complete inter-panel signal wiring

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/app/main_window.py

@@ -47,6 +47,10 @@ class MainWindow(QMainWindow):
     # ------------------------------------------------------------------
 
     def _build_ui(self):
+        # Fine-tune state: track which queue item is currently being edited
+        self._active_queue_item = None
+        self._loading_queue_item = False  # suppress fine-tune marking during item load
+
         root = QWidget()
         root.setObjectName("root")
         layout = QVBoxLayout(root)
@@ -246,20 +250,96 @@ class MainWindow(QMainWindow):
     # ------------------------------------------------------------------
 
     def _connect_signals(self):
-        """Connect inter-panel signals needed for the queue workflow."""
-        # Asset lists → queue rebuilds automatically
+        # ── Asset lists ────────────────────────────────────────────────────
         self.image_list_panel.garments_changed.connect(self.queue_panel.set_garments)
         self.image_list_panel.prints_changed.connect(self.queue_panel.set_prints)
-        # Queue row selection → preview canvas
+        # Direct preview clicks → canvas (outside of queue flow)
+        self.image_list_panel.garment_preview_changed.connect(self._on_garment_preview)
+        self.image_list_panel.print_preview_changed.connect(self._on_print_preview)
+
+        # ── Queue ──────────────────────────────────────────────────────────
         self.queue_panel.item_activated.connect(self._on_queue_item_activated)
 
+        # ── Canvas ↔ TransformPanel bidirectional sync ─────────────────────
+        # set_transform() on either side does NOT re-emit → no signal loop
+        self.image_canvas.transform_changed.connect(self.transform_panel.set_transform)
+        self.transform_panel.transform_changed.connect(self.image_canvas.set_transform)
+
+        # Both change paths feed fine-tune detection
+        self.image_canvas.transform_changed.connect(self._on_transform_changed)
+        self.transform_panel.transform_changed.connect(self._on_transform_changed)
+
+        # ── Template panel ─────────────────────────────────────────────────
+        # Template selection updates canvas, param panel, and queue template
+        self.template_panel.template_applied.connect(self.image_canvas.set_transform)
+        self.template_panel.template_applied.connect(self.transform_panel.set_transform)
+        self.template_panel.template_applied.connect(self.queue_panel.set_transform)
+
+        # ── Export panel secondary buttons → template panel ────────────────
+        self.export_panel.apply_as_template.connect(self.template_panel._save_as_template)
+        self.export_panel.reset_to_template.connect(self.template_panel._reset_to_template)
+
+    def _on_garment_preview(self, asset):
+        """Load a garment from the asset list into the canvas for direct preview."""
+        self._active_queue_item = None   # leave queue mode
+        if not asset:
+            self.export_panel.set_garment(None)
+            return
+        path = str(asset.path)
+        self.image_canvas.load_garment(path)
+        self.export_panel.set_garment(path)
+        # Tell template panel the garment dimensions so ratio→pixel conversion works
+        try:
+            from PIL import Image as _PilImage
+            with _PilImage.open(path) as img:
+                self.template_panel.set_garment_size(img.width, img.height)
+        except Exception:
+            pass
+
+    def _on_print_preview(self, asset):
+        """Load a print from the asset list into the canvas for direct preview."""
+        self._active_queue_item = None
+        if not asset:
+            self.export_panel.set_print(None)
+            return
+        path = str(asset.path)
+        self.image_canvas.load_print(path)
+        self.export_panel.set_print(path)
+
     def _on_queue_item_activated(self, item):
-        """Load garment and print from a selected queue item into the canvas."""
-        self.image_canvas.load_garment(str(item.garment.path))
-        self.image_canvas.load_print(str(item.print_asset.path))
-        if item.transform:
-            self.image_canvas.set_transform(item.transform)
-            self.transform_panel.set_transform(item.transform)
+        """Load a queue item into the canvas and arm fine-tune tracking."""
+        self._active_queue_item = item
+        self._loading_queue_item = True
+        try:
+            garment_path = str(item.garment.path)
+            print_path = str(item.print_asset.path)
+            self.image_canvas.load_garment(garment_path)
+            self.image_canvas.load_print(print_path)
+            self.export_panel.set_garment(garment_path)
+            self.export_panel.set_print(print_path)
+            # If the item already has a fine-tuned transform, restore it
+            if item.transform:
+                self.image_canvas.set_transform(item.transform)
+                self.transform_panel.set_transform(item.transform)
+            # Keep template panel garment size in sync
+            try:
+                from PIL import Image as _PilImage
+                with _PilImage.open(garment_path) as img:
+                    self.template_panel.set_garment_size(img.width, img.height)
+            except Exception:
+                pass
+        finally:
+            self._loading_queue_item = False
+
+    def _on_transform_changed(self, state):
+        """Route transform changes to panels and mark the active queue item fine-tuned."""
+        # Keep template panel and export panel up to date for save/export actions
+        self.template_panel.set_transform(state)
+        self.export_panel.set_transform(state)
+        # Mark the active queue item as fine-tuned (suppressed during item load)
+        if self._loading_queue_item or self._active_queue_item is None:
+            return
+        self.queue_panel.mark_item_fine_tuned(self._active_queue_item, state)
 
     # ------------------------------------------------------------------
     # Style  (ref: docs/07-ui-design.md §10)