improve selection of audio source

src/auracast/server/multicast_frontend.py

@@ -203,8 +203,21 @@ else:
     # Input device selection for USB mode
     if audio_mode == "USB/Network":
         resp = requests.get(f"{BACKEND_URL}/audio_inputs")
-        input_options = [f"{d['id']}:{d['name']}" for d in resp.json().get('inputs', [])]
+        device_list = resp.json().get('inputs', [])
+        # Display "name [id]" but use name as value
+        input_options = [f"{d['name']} [{d['id']}]" for d in device_list]
+        option_name_map = {f"{d['name']} [{d['id']}]": d['name'] for d in device_list}
+        device_names = [d['name'] for d in device_list]
 
+        # Determine default input by name
+        default_input_name = saved_settings.get('input_device')
+        if default_input_name not in device_names and device_names:
+            default_input_name = device_names[0]
+        default_input_label = None
+        for label, name in option_name_map.items():
+            if name == default_input_name:
+                default_input_label = label
+                break
         if not input_options:
             st.warning("No hardware audio input devices found. Plug in a USB input device and click Refresh.")
             if st.button("Refresh"):
@@ -215,11 +228,13 @@ else:
                 st.rerun()
             input_device = None
         else:
-            if default_input not in input_options:
-                default_input = input_options[0]
             col1, col2 = st.columns([3, 1], vertical_alignment="bottom")
             with col1:
-                selected_option = st.selectbox("Input Device", input_options, index=input_options.index(default_input))
+                selected_option = st.selectbox(
+                    "Input Device",
+                    input_options,
+                    index=input_options.index(default_input_label) if default_input_label in input_options else 0
+                )
             with col2:
                 if st.button("Refresh"):
                     try:
@@ -227,8 +242,8 @@ else:
                     except Exception as e:
                         st.error(f"Failed to refresh devices: {e}")
                     st.rerun()
-            # We send only the numeric/card identifier (before :) or 'default'
-            input_device = selected_option.split(":", 1)[0] if ":" in selected_option else selected_option
+            # Send only the device name to backend
+            input_device = option_name_map[selected_option] if selected_option in option_name_map else None
     else:
         input_device = None