Auto-detection DSLR: bascule automatique quand branche/rebranche

- Verification toutes les 5s si un DSLR est disponible
- Bascule auto de webcam/simulation vers DSLR
- Reconnexion auto si le DSLR est deconnecte

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

backend/main.py

@@ -13,7 +13,11 @@ from backend.config import (
     RACINE, DOSSIER_PHOTOS, DOSSIER_EXPORTS, DOSSIER_OVERLAYS, DOSSIER_FONDS, DOSSIER_ANIMATIONS,
     charger_config, sauvegarder_config, mettre_a_jour_config,
 )
-from backend.camera import camera
+from backend.camera import camera, GPHOTO2_DISPONIBLE
+try:
+    import gphoto2 as gp
+except ImportError:
+    gp = None
 from backend.gallery import lister_photos, compter_photos, supprimer_photo, vider_galerie
 from backend.effects import appliquer_filtre, appliquer_overlay, chroma_key, lister_overlays, lister_fonds, FILTRES
 from backend.collage import creer_strip, creer_collage, creer_impression_strip
@@ -29,12 +33,35 @@ log = logging.getLogger("photobooth")
 clients_ws: list[WebSocket] = []
 
 
+async def surveiller_dslr():
+    """Verifie periodiquement si un DSLR est branche et bascule dessus."""
+    while True:
+        await asyncio.sleep(5)
+        try:
+            if camera.mode != "gphoto2" and GPHOTO2_DISPONIBLE:
+                dslrs = gp.Camera.autodetect()
+                if len(dslrs) > 0:
+                    log.info(f"DSLR detecte : {dslrs[0][0]}, bascule automatique")
+                    camera.connecter(source="gphoto2")
+            elif camera.mode == "gphoto2":
+                # Verifier que le DSLR repond encore
+                try:
+                    camera.camera.get_summary()
+                except Exception:
+                    log.warning("DSLR deconnecte, reconnexion...")
+                    camera.connecter()
+        except Exception:
+            pass
+
+
 @asynccontextmanager
 async def lifespan(app: FastAPI):
     """Demarrage et arret de l'application."""
     log.info("Demarrage du photobooth")
     camera.connecter()
+    task = asyncio.create_task(surveiller_dslr())
     yield
+    task.cancel()
     log.info("Arret du photobooth")
     camera.deconnecter()