central2.h

// Copyright 2024 The Pigweed Authors
//
// 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.
#pragma once
 
#include <optional>
 
#include "pw_async2/once_sender.h"
#include "pw_bluetooth/internal/raii_ptr.h"
#include "pw_bluetooth/low_energy/connection2.h"
#include "pw_bluetooth/low_energy/phy.h"
#include "pw_bluetooth/types.h"
#include "pw_chrono/system_clock.h"
#include "pw_result/expected.h"
 
namespace pw::bluetooth::low_energy {
 
class Central2 {
 public:
  struct ScanFilter {
    std::optional<Uuid> service_uuid;
 
    std::optional<Uuid> service_data_uuid;
 
    std::optional<uint16_t> manufacturer_id;
 
    std::optional<bool> connectable;
 
    std::optional<std::string_view> name;
 
    std::optional<int8_t> max_path_loss;
 
    std::optional<Uuid> solicitation_uuid;
  };
 
  enum class ScanType : uint8_t {
    kPassive,
    kActiveUsePublicAddress,
    kActiveUseRandomAddress,
    kActiveUseResolvablePrivateAddress,
  };
 
  struct ScanOptions {
    pw::span<const ScanFilter> filters;
 
    uint16_t interval;
 
    uint16_t window;
 
    ScanType scan_type;
 
    Phy phys = Phy::k1Megabit;
  };
 
  struct ScanResult {
    PeerId peer_id;
 
    bool connectable;
 
    std::optional<uint8_t> rssi;
 
    pw::multibuf::MultiBuf data;
 
    std::optional<InlineString<22>> name;
 
    chrono::SystemClock::time_point last_updated;
  };
 
  class ScanHandle {
   public:
    virtual ~ScanHandle() = default;
 
    virtual async2::Poll<pw::Result<ScanResult>> PendResult(
        async2::Context& cx) = 0;
 
   private:
    virtual void Release() = 0;
 
   public:
    using Ptr = internal::RaiiPtr<ScanHandle, &ScanHandle::Release>;
  };
 
  enum class ConnectError : uint8_t {
    kUnknownPeer,
 
    kInvalidOptions,
 
    kAlreadyExists,
 
    kCouldNotBeEstablished,
  };
 
  enum class StartScanError : uint8_t {
    kScanInProgress,
    kInvalidParameters,
    kInternal,
  };
 
  using ConnectResult = pw::expected<Connection2::Ptr, ConnectError>;
 
  using ScanStartResult = pw::expected<ScanHandle::Ptr, StartScanError>;
 
  virtual ~Central2() = default;
 
  virtual async2::OnceReceiver<ConnectResult> Connect(
      PeerId peer_id, Connection2::ConnectionOptions options) = 0;
 
  virtual async2::OnceReceiver<ScanStartResult> Scan(
      const ScanOptions& options) = 0;
};
 
}  // namespace pw::bluetooth::low_energy