Add manufacturer data filtering (#23)

* Add manufacturer data filtering

* Implement manufacturer data filter in windows

* Fix manufacturerData filtering on windows

* Fix linux

* Clean comments

---------

Co-authored-by: Foti Dim <fdimanidis@gmail.com>

darwin/Classes/UniversalBle.g.swift

@@ -129,20 +129,52 @@ struct UniversalBleCharacteristic {
   }
 }
 
+/// Scan Filters
+///
 /// Generated class from Pigeon that represents data sent in messages.
 struct UniversalScanFilter {
   var withServices: [String?]
+  var withManufacturerData: [UniversalManufacturerDataFilter?]
 
   static func fromList(_ list: [Any?]) -> UniversalScanFilter? {
     let withServices = list[0] as! [String?]
+    let withManufacturerData = list[1] as! [UniversalManufacturerDataFilter?]
 
     return UniversalScanFilter(
-      withServices: withServices
+      withServices: withServices,
+      withManufacturerData: withManufacturerData
     )
   }
   func toList() -> [Any?] {
     return [
-      withServices
+      withServices,
+      withManufacturerData,
+    ]
+  }
+}
+
+/// Generated class from Pigeon that represents data sent in messages.
+struct UniversalManufacturerDataFilter {
+  var companyIdentifier: Int64? = nil
+  var data: FlutterStandardTypedData? = nil
+  var mask: FlutterStandardTypedData? = nil
+
+  static func fromList(_ list: [Any?]) -> UniversalManufacturerDataFilter? {
+    let companyIdentifier: Int64? = isNullish(list[0]) ? nil : (list[0] is Int64? ? list[0] as! Int64? : Int64(list[0] as! Int32))
+    let data: FlutterStandardTypedData? = nilOrValue(list[1])
+    let mask: FlutterStandardTypedData? = nilOrValue(list[2])
+
+    return UniversalManufacturerDataFilter(
+      companyIdentifier: companyIdentifier,
+      data: data,
+      mask: mask
+    )
+  }
+  func toList() -> [Any?] {
+    return [
+      companyIdentifier,
+      data,
+      mask,
     ]
   }
 }
@@ -157,6 +189,8 @@ private class UniversalBlePlatformChannelCodecReader: FlutterStandardReader {
     case 130:
       return UniversalBleService.fromList(self.readValue() as! [Any?])
     case 131:
+      return UniversalManufacturerDataFilter.fromList(self.readValue() as! [Any?])
+    case 132:
       return UniversalScanFilter.fromList(self.readValue() as! [Any?])
     default:
       return super.readValue(ofType: type)
@@ -175,9 +209,12 @@ private class UniversalBlePlatformChannelCodecWriter: FlutterStandardWriter {
     } else if let value = value as? UniversalBleService {
       super.writeByte(130)
       super.writeValue(value.toList())
-    } else if let value = value as? UniversalScanFilter {
+    } else if let value = value as? UniversalManufacturerDataFilter {
       super.writeByte(131)
       super.writeValue(value.toList())
+    } else if let value = value as? UniversalScanFilter {
+      super.writeByte(132)
+      super.writeValue(value.toList())
     } else {
       super.writeValue(value)
     }

darwin/Classes/UniversalBleHelper.swift

@@ -143,11 +143,11 @@ public extension CBPeripheral {
 
 extension String {
     var validFullUUID: String {
-        let uuidLength = self.count
+        let uuidLength = count
         if uuidLength == 4 || uuidLength == 8 {
             let baseUuid = "00000000-0000-1000-8000-00805F9B34FB"
             let start = baseUuid.startIndex
-            let range = baseUuid.index(start, offsetBy: 4-uuidLength)..<baseUuid.index(start, offsetBy: 4)
+            let range = baseUuid.index(start, offsetBy: 4 - uuidLength) ..< baseUuid.index(start, offsetBy: 4)
             return baseUuid.replacingCharacters(in: range, with: self)
         } else {
             return self
@@ -155,6 +155,49 @@ extension String {
     }
 }
 
+extension FlutterStandardTypedData {
+    func toData() -> Data {
+        return Data(data)
+    }
+}
+
+func isManufacturerDataMatchingFilters(filters: [UniversalManufacturerDataFilter], msd: Data?) -> Bool {
+    guard let msd = msd, !msd.isEmpty else {
+        return false
+    }
+    for filter in filters {
+        guard let companyIdentifier: Int64 = filter.companyIdentifier else {
+            continue
+        }
+        let manufacturerId = msd.subdata(in: 0 ..< 2).withUnsafeBytes { $0.load(as: UInt16.self) }
+        let manufacturerData = msd.subdata(in: 2 ..< msd.count)
+        if manufacturerId == companyIdentifier && findData(find: filter.data?.toData(), inData: manufacturerData, usingMask: filter.mask?.toData()) {
+            return true
+        }
+    }
+    return false
+}
+
+func findData(find: Data?, inData data: Data, usingMask mask: Data?) -> Bool {
+    if let find = find {
+        // If mask is null, use a default mask of all 1s
+        let mask = mask ?? Data(repeating: 0xFF, count: find.count)
+
+        // Ensure find & mask are same length
+        guard find.count == mask.count else {
+            return false
+        }
+
+        for i in 0 ..< find.count {
+            // Perform bitwise AND with mask and then compare
+            if (find[i] & mask[i]) != (data[i] & mask[i]) {
+                return false
+            }
+        }
+    }
+    return true
+}
+
 // Future classes
 class CharacteristicReadFuture {
     let deviceId: String

darwin/Classes/UniversalBlePlugin.swift

@@ -27,6 +27,7 @@ private var discoveredPeripherals = [String: CBPeripheral]()
 private class BleCentralDarwin: NSObject, UniversalBlePlatformChannel, CBCentralManagerDelegate, CBPeripheralDelegate {
   var callbackChannel: UniversalBleCallbackChannel
   private lazy var manager: CBCentralManager = .init(delegate: self, queue: nil)
+  private var scanFilter: UniversalScanFilter? = nil
   private var discoveredServicesProgressMap: [String: [UniversalBleService]] = [:]
   private var characteristicReadFutures = [CharacteristicReadFuture]()
   private var characteristicWriteFutures = [CharacteristicWriteFuture]()
@@ -57,18 +58,20 @@ private class BleCentralDarwin: NSObject, UniversalBlePlatformChannel, CBCentral
   }
 
   func startScan(filter: UniversalScanFilter?) throws {
-    
     // Apply services filter
     var withServices: [CBUUID] = []
     for service in filter?.withServices ?? [] {
       if let service = service {
-          if UUID(uuidString: service.validFullUUID) == nil {
+        if UUID(uuidString: service.validFullUUID) == nil {
           throw FlutterError(code: "IllegalArgument", message: "Invalid service UUID:\(service)", details: nil)
         }
         withServices.append(CBUUID(string: service))
       }
     }
 
+    // Save scanFilter for later user
+    scanFilter = filter
+
     manager.scanForPeripherals(withServices: withServices)
   }
 
@@ -241,6 +244,16 @@ private class BleCentralDarwin: NSObject, UniversalBlePlatformChannel, CBCentral
     discoveredPeripherals[peripheral.uuid.uuidString] = peripheral
     let manufacturerData = advertisementData[CBAdvertisementDataManufacturerDataKey] as? Data
     let services = advertisementData[CBAdvertisementDataServiceUUIDsKey] as? [CBUUID]
+
+    // Handle ScanFilters
+    if let filter = scanFilter {
+      let manufacturerFilter = filter.withManufacturerData.compactMap { $0 }
+      // If scan filters are not empty, check if manufacturer data matches filters
+      if !manufacturerFilter.isEmpty, !isManufacturerDataMatchingFilters(filters: manufacturerFilter, msd: manufacturerData) {
+        return
+      }
+    }
+
     callbackChannel.onScanResult(result: UniversalBleScanResult(
       deviceId: peripheral.uuid.uuidString,
       name: peripheral.name,