nearby sdk refactor

PiperOrigin-RevId: 425434260

internal/platform/implementation/ble.h

@@ -0,0 +1,125 @@
+// Copyright 2020 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef PLATFORM_API_BLE_H_
+#define PLATFORM_API_BLE_H_
+
+#include "internal/platform/implementation/bluetooth_classic.h"
+#include "internal/platform/byte_array.h"
+#include "internal/platform/cancellation_flag.h"
+#include "internal/platform/input_stream.h"
+#include "internal/platform/output_stream.h"
+
+namespace location {
+namespace nearby {
+namespace api {
+
+// Opaque wrapper over a BLE peripheral. Must contain enough data about a
+// particular BLE device to connect to its GATT server.
+class BlePeripheral {
+ public:
+  virtual ~BlePeripheral() = default;
+
+  virtual std::string GetName() const = 0;
+
+  virtual ByteArray GetAdvertisementBytes(
+      const std::string& service_id) const = 0;
+};
+
+class BleSocket {
+ public:
+  virtual ~BleSocket() = default;
+
+  // Returns the InputStream of the BleSocket.
+  // On error, returned stream will report Exception::kIo on any operation.
+  //
+  // The returned object is not owned by the caller, and can be invalidated once
+  // the BleSocket object is destroyed.
+  virtual InputStream& GetInputStream() = 0;
+
+  // Returns the OutputStream of the BleSocket.
+  // On error, returned stream will report Exception::kIo on any operation.
+  //
+  // The returned object is not owned by the caller, and can be invalidated once
+  // the BleSocket object is destroyed.
+  virtual OutputStream& GetOutputStream() = 0;
+
+  // Conforms to the same contract as
+  // https://developer.android.com/reference/android/bluetooth/BluetoothSocket.html#close().
+  //
+  // Returns Exception::kIo on error, Exception::kSuccess otherwise.
+  virtual Exception Close() = 0;
+
+  // Returns valid BlePeripheral pointer if there is a connection, and
+  // nullptr otherwise.
+  virtual BlePeripheral* GetRemotePeripheral() = 0;
+};
+
+// Container of operations that can be performed over the BLE medium.
+class BleMedium {
+ public:
+  virtual ~BleMedium() = default;
+
+  virtual bool StartAdvertising(
+      const std::string& service_id, const ByteArray& advertisement_bytes,
+      const std::string& fast_advertisement_service_uuid) = 0;
+  virtual bool StopAdvertising(const std::string& service_id) = 0;
+
+  // Callback that is invoked when a discovered peripheral is found or lost.
+  struct DiscoveredPeripheralCallback {
+    std::function<void(BlePeripheral& peripheral, const std::string& service_id,
+                       bool fast_advertisement)>
+        peripheral_discovered_cb =
+            DefaultCallback<BlePeripheral&, const std::string&, bool>();
+    std::function<void(BlePeripheral& peripheral,
+                       const std::string& service_id)>
+        peripheral_lost_cb =
+            DefaultCallback<BlePeripheral&, const std::string&>();
+  };
+
+  // Returns true once the BLE scan has been initiated.
+  virtual bool StartScanning(const std::string& service_id,
+                             const std::string& fast_advertisement_service_uuid,
+                             DiscoveredPeripheralCallback callback) = 0;
+
+  // Returns true once BLE scanning for service_id is well and truly stopped;
+  // after this returns, there must be no more invocations of the
+  // DiscoveredPeripheralCallback passed in to StartScanning() for service_id.
+  virtual bool StopScanning(const std::string& service_id) = 0;
+
+  // Callback that is invoked when a new connection is accepted.
+  struct AcceptedConnectionCallback {
+    std::function<void(BleSocket& socket, const std::string& service_id)>
+        accepted_cb = DefaultCallback<BleSocket&, const std::string&>();
+  };
+
+  // Returns true once BLE socket connection requests to service_id can be
+  // accepted.
+  virtual bool StartAcceptingConnections(
+      const std::string& service_id, AcceptedConnectionCallback callback) = 0;
+  virtual bool StopAcceptingConnections(const std::string& service_id) = 0;
+
+  // Connects to a BLE peripheral.
+  // On success, returns a new BleSocket.
+  // On error, returns nullptr.
+  virtual std::unique_ptr<BleSocket> Connect(
+      BlePeripheral& peripheral, const std::string& service_id,
+      CancellationFlag* cancellation_flag) = 0;
+};
+
+}  // namespace api
+}  // namespace nearby
+}  // namespace location
+
+#endif  // PLATFORM_API_BLE_H_