nearby: snapshot of cl/304428753

Signed-off-by: Alexey Polyudov <apolyudov@google.com>
Change-Id: I0023ac6e40456fc4a8169c3173bcbff3b5ccc476

cpp/platform/api2/ble.h

@@ -0,0 +1,111 @@
+#ifndef PLATFORM_API2_BLE_H_
+#define PLATFORM_API2_BLE_H_
+
+#include "platform/api2/bluetooth_classic.h"
+#include "platform/api2/input_stream.h"
+#include "platform/api2/output_stream.h"
+#include "platform/byte_array.h"
+#include "absl/strings/string_view.h"
+
+namespace location {
+namespace nearby {
+
+// 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() {}
+
+  // The returned Ptr is not owned by the caller, and can be invalidated once
+  // the corresponding BLEPeripheral object is destroyed.
+  virtual BluetoothDevice& GetBluetoothDevice() = 0;
+};
+
+class BleSocket {
+ public:
+  virtual ~BleSocket() {}
+
+  // 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;
+
+  // The returned object is not owned by the caller, and can be invalidated once
+  // the BleSocket object is destroyed.
+  virtual BlePeripheral& GetRemotePeripheral() = 0;
+};
+
+// Container of operations that can be performed over the BLE medium.
+class BleMedium {
+ public:
+  virtual ~BleMedium() {}
+
+  virtual bool StartAdvertising(absl::string_view service_id,
+                                const ByteArray& advertisement) = 0;
+  virtual void StopAdvertising(absl::string_view service_id) = 0;
+
+  class DiscoveredPeripheralCallback {
+   public:
+    virtual ~DiscoveredPeripheralCallback() {}
+
+    // The BlePeripheral* is not owned by callbacks.
+    // It is passed to give access to its non-const methods.
+    // It is guaranteed to be valid for the duration of call.
+    virtual void OnPeripheralDiscovered(BlePeripheral* ble_peripheral,
+                                        absl::string_view service_id,
+                                        const ByteArray& advertisement) = 0;
+    virtual void OnPeripheralLost(BlePeripheral* ble_peripheral,
+                                  absl::string_view service_id) = 0;
+  };
+
+  // Returns true once the BLE scan has been initiated.
+  virtual bool StartScanning(
+      absl::string_view service_id,
+      const DiscoveredPeripheralCallback& discovered_peripheral_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 void StopScanning(absl::string_view service_id) = 0;
+
+  // Callback that is invoked when a new connection is accepted.
+  class AcceptedConnectionCallback {
+   public:
+    virtual ~AcceptedConnectionCallback() {}
+
+    virtual void OnConnectionAccepted(std::unique_ptr<BleSocket> socket,
+                                      absl::string_view service_id) = 0;
+  };
+
+  // Returns true once BLE socket connection requests to service_id can be
+  // accepted.
+  virtual bool StartAcceptingConnections(
+      absl::string_view service_id,
+      const AcceptedConnectionCallback& accepted_connection_callback) = 0;
+  virtual void StopAcceptingConnections(const std::string& service_id) = 0;
+
+  // BlePeripheral* is not owned by this call;
+  // it must remain valid for the duration of a call.
+  virtual std::unique_ptr<BleSocket> Connect(BlePeripheral* ble_peripheral,
+                                             absl::string_view service_id) = 0;
+};
+
+}  // namespace nearby
+}  // namespace location
+
+#endif  // PLATFORM_API2_BLE_H_