ios: add a connectionState enum for the frontend

We are either scanning, connecting/pairing, or connected. This should
help the frontend display everything appropriately.

Author: benma

backend/devices/bluetooth/bluetooth.go

@@ -21,6 +21,18 @@ import (
 	"github.com/sirupsen/logrus"
 )
 
+// ConnectionState represents the current Bluetooth connection state.
+type ConnectionState string
+
+const (
+	// ConnectionStateScanning means actively searching for devices.
+	ConnectionStateScanning ConnectionState = "scanning"
+	// ConnectionStateConnecting means a connection & pairing attempt is in progress.
+	ConnectionStateConnecting ConnectionState = "connecting"
+	// ConnectionStateConnected means successfully connected and paired.
+	ConnectionStateConnected ConnectionState = "connected"
+)
+
 // Peripheral is a bluetooth peripheral.
 type Peripheral struct {
 	Identifier      string  `json:"identifier"`
@@ -33,9 +45,8 @@ type State struct {
 	// BluetoothAvailable is false if bluetooth is powered off or otherwise unavailable.
 	BluetoothAvailable bool          `json:"bluetoothAvailable"`
 	Peripherals        []*Peripheral `json:"peripherals"`
-	// Connecting is true from the moment we try to connect until after we are paired (or until
-	// either step fails).
-	Connecting bool `json:"connecting"`
+	// ConnectionState shows the current bluetooth connection phase
+	ConnectionState ConnectionState `json:"connectionState"`
 }
 
 // Bluetooth manages a list of peripherals.
@@ -52,7 +63,8 @@ type Bluetooth struct {
 func New(log *logrus.Entry) *Bluetooth {
 	b := &Bluetooth{
 		state: &State{
-			Peripherals: []*Peripheral{},
+			Peripherals:     []*Peripheral{},
+			ConnectionState: ConnectionStateScanning,
 		},
 		log: log,
 	}

frontends/ios/BitBoxApp/BitBoxApp/Bluetooth.swift

@@ -19,11 +19,18 @@ struct ProductInfo: Codable {
     }
 }
 
+enum ConnectionState: String, Codable {
+    // we are scanning for peripherals by default
+    case scanning
+    // from the moment we try to connect until after we are paired (or until either step fails).
+    case connecting
+    case connected
+}
+
 struct State {
     var bluetoothAvailable: Bool
     var discoveredPeripherals: [UUID: PeripheralMetadata]
-    // true from the moment we try to connect until after we are paired (or until either step fails).
-    var connecting: Bool
+    var connectionState: ConnectionState
 }
 
 struct PeripheralMetadata {
@@ -43,14 +50,18 @@ var pairedDeviceIdentifiers: Set<String> {
 }
 
 class BluetoothManager: NSObject, ObservableObject, CBCentralManagerDelegate, CBPeripheralDelegate {
-    private var state: State = State(bluetoothAvailable: false, discoveredPeripherals: [:], connecting: false)
+    private var state: State = State(
+        bluetoothAvailable: false,
+        discoveredPeripherals: [:],
+        connectionState: .scanning // Initial state
+    )
 
     var centralManager: CBCentralManager!
     var connectedPeripheral: CBPeripheral?
     var pWriter: CBCharacteristic?
     var pReader: CBCharacteristic?
     var pProduct: CBCharacteristic?
-    
+
     private var isPaired: Bool = false
 
     // Peripherals in this set will not be auto-connected even if previously paired.
@@ -76,7 +87,7 @@ class BluetoothManager: NSObject, ObservableObject, CBCentralManagerDelegate, CB
         guard let metadata = state.discoveredPeripherals[peripheralID] else { return }
         centralManager.stopScan()
         state.discoveredPeripherals[peripheralID]?.connectionError = nil
-        state.connecting = true
+        state.connectionState = .connecting
         updateBackendState()
         centralManager.connect(metadata.peripheral, options: nil)
     }
@@ -86,6 +97,7 @@ class BluetoothManager: NSObject, ObservableObject, CBCentralManagerDelegate, CB
               !centralManager.isScanning,
               connectedPeripheral == nil else { return }
         state.discoveredPeripherals.removeAll()
+        state.connectionState = .scanning
         updateBackendState()
         centralManager.scanForPeripherals(
           withServices: [CBUUID(string: "e1511a45-f3db-44c0-82b8-6c880790d1f1")],
@@ -150,10 +162,10 @@ class BluetoothManager: NSObject, ObservableObject, CBCentralManagerDelegate, CB
     func centralManager(_ central: CBCentralManager, didFailToConnect peripheral: CBPeripheral, error: Error?) {
         let errorMessage = error?.localizedDescription ?? "unknown error"
         state.discoveredPeripherals[peripheral.identifier]?.connectionError = errorMessage
-        state.connecting = false
-        dontAutoConnectSet.insert(peripheral.identifier)
         updateBackendState()
+        dontAutoConnectSet.insert(peripheral.identifier)
         print("BLE: connection failed to \(peripheral.name ?? "unknown device"): \(errorMessage)")
+        restartScan()
     }
 
     func peripheral(_ peripheral: CBPeripheral, didDiscoverServices error: Error?) {
@@ -240,29 +252,29 @@ class BluetoothManager: NSObject, ObservableObject, CBCentralManagerDelegate, CB
                 // Add to paired devices
                 pairedDeviceIdentifiers.insert(peripheral.identifier.uuidString)
             }
-            state.connecting = false
+            state.connectionState = .connected
             updateBackendState()
             // Invoke device manager to scan now, which will make it detect the device being connected
             // (or disconnected, in case the product string indicates that) now instead of waiting for
             // the next scan.
             MobileserverUsbUpdate()
         }
     }
-    
+
     func handleDisconnect() {
         connectedPeripheral = nil
         pReader = nil
         pWriter = nil
         pProduct = nil
         state.discoveredPeripherals.removeAll()
-        state.connecting = false
+        state.connectionState = .scanning
         isPaired = false
         updateBackendState()
-        
+
         // Have the backend scan right away, which will make it detect that we disconnected.
         // Otherwise there would be up to a second of delay (the backend device manager scan interval).
         MobileserverUsbUpdate()
-        
+
         restartScan()
     }
 
@@ -299,7 +311,7 @@ class BluetoothManager: NSObject, ObservableObject, CBCentralManagerDelegate, CB
               let value = pProduct.value else {
             return nil
         }
-        
+
         if value.isEmpty {
             return nil
         }
@@ -326,7 +338,7 @@ class BluetoothManager: NSObject, ObservableObject, CBCentralManagerDelegate, CB
         struct StateJSON: Codable {
             let bluetoothAvailable: Bool
             let peripherals: [PeripheralJSON]
-            let connecting: Bool
+            let connectionState: ConnectionState
         }
 
         // Convert discoveredPeripherals to the JSON structure
@@ -338,7 +350,11 @@ class BluetoothManager: NSObject, ObservableObject, CBCentralManagerDelegate, CB
             )
         }
 
-        let state = StateJSON(bluetoothAvailable: state.bluetoothAvailable, peripherals: peripherals, connecting: state.connecting)
+        let state = StateJSON(
+            bluetoothAvailable: state.bluetoothAvailable,
+            peripherals: peripherals,
+            connectionState: state.connectionState
+        )
 
         do {
             let encoder = JSONEncoder()

frontends/web/src/api/bluetooth.ts

@@ -26,7 +26,7 @@ export type TPeripheral = {
 export type TState = {
   bluetoothAvailable: boolean;
   peripherals: TPeripheral[];
-  connecting: boolean;
+  connectionState: 'scanning' | 'connecting' | 'connected';
 };
 
 export const getState = (): Promise<TState> => {

frontends/web/src/components/bluetooth/bluetooth.tsx

@@ -37,7 +37,7 @@ const _Bluetooth = () => {
         {t('bluetooth.select')}
       </div>
       <div className={styles.container}>
-        { state.connecting ? <p>connecting</p> : null }
+        State: { state.connectionState }
         {state.peripherals.map(peripheral => {
           return (
             <ActionableItem