Merge pull request #5473 from woocommerce/issue/5333-battery-level-updating

[Mobile Payments] Implement didReportBatteryLevel delegate to get battery level updates from readers

Author: allendav

Hardware/Hardware/CardReader/CardReader.swift

@@ -1,6 +1,6 @@
 /// Models a Card Reader. This is the public struct that clients of
 /// Hardware are expected to consume.
-/// CardReader is meant to be inmutable. 
+/// CardReader is meant to be immutable.
 public struct CardReader {
 
     /// The CardReader serial number

Hardware/Hardware/CardReader/StripeCardReader/StripeCardReaderService.swift

@@ -521,6 +521,31 @@ extension StripeCardReaderService: BluetoothReaderDelegate {
             break
         }
     }
+
+    /// Receive changes in the reader battery level. Note that the SDK will call this delegate
+    /// not more frequently than every 10 minutes and will not report battery level during payment collection.
+    /// See `https://github.com/stripe/stripe-terminal-ios/issues/121#issuecomment-966589886`
+    ///
+    public func reader(_ reader: Reader, didReportBatteryLevel batteryLevel: Float, status: BatteryStatus, isCharging: Bool) {
+        let connectedReaders = connectedReadersSubject.value
+
+        guard let connectedReader = connectedReaders.first else {
+            return
+        }
+
+        let connectedReaderWithUpdatedBatteryLevel = CardReader(
+            serial: connectedReader.serial,
+            vendorIdentifier: connectedReader.vendorIdentifier,
+            name: connectedReader.name,
+            status: connectedReader.status,
+            softwareVersion: connectedReader.softwareVersion,
+            batteryLevel: batteryLevel,
+            readerType: connectedReader.readerType,
+            locationId: connectedReader.locationId
+        )
+
+        connectedReadersSubject.send([connectedReaderWithUpdatedBatteryLevel])
+    }
 }
 
 // MARK: - Terminal delegate

WooCommerce/Classes/ViewRelated/Dashboard/Settings/CardReadersV2/CardReaderSettingsConnectedViewModel.swift

@@ -102,6 +102,7 @@ final class CardReaderSettingsConnectedViewModel: CardReaderSettingsPresentedVie
         updateReaderID()
         updateBatteryLevel()
         updateSoftwareVersion()
+        didUpdate?()
     }
 
     private func updateReaderID() {