// Copyright 2017 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef SRC_CONNECTIVITY_BLUETOOTH_CORE_BT_HOST_TESTING_FAKE_PEER_H_
#define SRC_CONNECTIVITY_BLUETOOTH_CORE_BT_HOST_TESTING_FAKE_PEER_H_

#include <unordered_set>

#include <fbl/macros.h>

#include "src/connectivity/bluetooth/core/bt-host/common/byte_buffer.h"
#include "src/connectivity/bluetooth/core/bt-host/common/device_address.h"
#include "src/connectivity/bluetooth/core/bt-host/hci-spec/le_connection_parameters.h"
#include "src/connectivity/bluetooth/core/bt-host/hci-spec/protocol.h"
#include "src/connectivity/bluetooth/core/bt-host/hci/connection.h"
#include "src/connectivity/bluetooth/core/bt-host/testing/fake_gatt_server.h"
#include "src/connectivity/bluetooth/core/bt-host/testing/fake_l2cap.h"
#include "src/connectivity/bluetooth/core/bt-host/testing/fake_sdp_server.h"
#include "src/connectivity/bluetooth/core/bt-host/testing/fake_signaling_server.h"

namespace bt::testing {

class FakeController;

// FakePeer is used to emulate a remote Bluetooth device.
class FakePeer {
 public:
  // NOTE: Setting |connectable| to true will result in a "Connectable and
  // Scannable Advertisement" (i.e. ADV_IND) even if |scannable| is set to
  // false. This is OK since we use |scannable| to drive the receipt of Scan
  // Response PDUs: we use this to test the condition in which the advertisement
  // is scannable but the host never receives a scan response.
  explicit FakePeer(const DeviceAddress& address, bool connectable = true, bool scannable = true);

  void SetAdvertisingData(const ByteBuffer& data);

  void set_advertising_enabled(bool enabled) { advertising_enabled_ = enabled; }

  // Mark this device for directed advertising. CreateAdvertisingReportEvent
  // will return directed advertisements only.
  void enable_directed_advertising(bool enable) { directed_ = enable; }

  // Toggles whether the address of this device represents a resolved RPA.
  void set_address_resolved(bool value) { address_resolved_ = value; }

  // TODO(armansito): Come up with a better scheme to determine supported transport type instead of
  // relying on address type, which doesn't translate well to dual-mode.
  bool supports_bredr() const {
    // All BR/EDR devices have inquiry responses.
    return address().type() == DeviceAddress::Type::kBREDR;
  }

  // TODO(armansito): Come up with a better scheme to determine supported transport type instead of
  // relying on address type, which doesn't translate well to dual-mode.
  bool supports_le() const { return address().type() != DeviceAddress::Type::kBREDR; }

  // |should_batch_reports| indicates to the FakeController that the SCAN_IND
  // report should be included in the same HCI LE Advertising Report Event
  // payload that includes the original advertising data (see comments for
  // should_batch_reports()).
  void SetScanResponse(bool should_batch_reports, const ByteBuffer& data);

  // Generates and returns a LE Advertising Report Event payload. If
  // |include_scan_rsp| is true, then the returned PDU will contain two reports
  // including the SCAN_IND report.
  DynamicByteBuffer CreateAdvertisingReportEvent(bool include_scan_rsp) const;

  // Generates a LE Advertising Report Event payload containing the scan
  // response.
  DynamicByteBuffer CreateScanResponseReportEvent() const;

  // Generates a Inquiry Response Event payload containing a inquiry result
  // response.
  DynamicByteBuffer CreateInquiryResponseEvent(hci::InquiryMode mode) const;

  const DeviceAddress& address() const { return address_; }

  // The local name of the device. Used in HCI Remote Name Request event.
  std::string name() const { return name_; }

  void set_name(std::string name) { name_ = name; }

  // Indicates whether or not this device should include the scan response and
  // the advertising data in the same HCI LE Advertising Report Event. This is
  // used to test that the host stack can correctly consolidate advertising
  // reports when the payloads are spread across events and when they are
  // batched together in the same event.
  //
  // This isn't used by FakePeer directly to generated batched reports. Rather
  // it is a hint to the corresponding FakeController which decides how the
  // reports should be generated.
  bool should_batch_reports() const { return should_batch_reports_; }

  // Returns true if this device should send advertisements.
  bool advertising_enabled() const { return advertising_enabled_; }

  // Returns true if this device is scannable. We use this to tell
  // FakeController whether or not it should send scan response PDUs.
  bool scannable() const { return scannable_; }

  bool connectable() const { return connectable_; }

  bool connected() const { return connected_; }
  void set_connected(bool connected) { connected_ = connected; }

  void set_class_of_device(DeviceClass class_of_device) { class_of_device_ = class_of_device; }

  const hci::LEConnectionParameters& le_params() const { return le_params_; }
  void set_le_params(const hci::LEConnectionParameters& value) { le_params_ = value; }

  bool supports_ll_conn_update_procedure() const { return supports_ll_conn_update_procedure_; }
  void set_supports_ll_conn_update_procedure(bool supports) {
    supports_ll_conn_update_procedure_ = supports;
  }

  hci::LESupportedFeatures le_features() const { return le_features_; }
  void set_le_features(hci::LESupportedFeatures le_features) { le_features_ = le_features; }

  // The response status that will be returned when this device receives a LE
  // Create Connection command.
  hci::StatusCode connect_response() const { return connect_response_; }
  void set_connect_response(hci::StatusCode response) { connect_response_ = response; }

  // The status that will be returned in the Command Status event in response to
  // a LE Create Connection command. If this is set to anything other than
  // hci::StatusCode::kSuccess, then connect_response() will have no effect.
  hci::StatusCode connect_status() const { return connect_status_; }
  void set_connect_status(hci::StatusCode status) { connect_status_ = status; }

  bool force_pending_connect() const { return force_pending_connect_; }
  void set_force_pending_connect(bool value) { force_pending_connect_ = value; }

  void AddLink(hci::ConnectionHandle handle);
  void RemoveLink(hci::ConnectionHandle handle);
  bool HasLink(hci::ConnectionHandle handle) const;

  using HandleSet = std::unordered_set<hci::ConnectionHandle>;
  const HandleSet& logical_links() const { return logical_links_; }

  // Marks this device as disconnected. Clears and returns all logical link
  // handles.
  HandleSet Disconnect();

  // Returns the FakeController that has been assigned to this device.
  FakeController* ctrl() const { return ctrl_; }

  // Returns the FakeSdpServer associated with this device.
  FakeSdpServer* sdp_server() { return &sdp_server_; }

 private:
  friend class FakeController;

  // Called by a FakeController when a FakePeer is registered with it.
  void set_ctrl(FakeController* ctrl) { ctrl_ = ctrl; }

  void WriteScanResponseReport(hci::LEAdvertisingReportData* report) const;

  // Validate received L2CAP packets and then route them to the FakeL2cap
  // instance owned by the device. The FakeL2cap instance will process the
  // packet and route it to the appropriate packet handler.
  void OnRxL2CAP(hci::ConnectionHandle conn, const ByteBuffer& pdu);

  // Sends packets over channel ID |cid| and handle |conn| using the
  // FakeController's SendL2CapBFrame function. Assumes that input buffer
  // |packet| has signaling packet header intact but does not have an L2CAP
  //  packet header.
  void SendPacket(hci::ConnectionHandle conn, l2cap::ChannelId cid, const ByteBuffer& packet);

  // The FakeController that this FakePeer has been assigned to.
  FakeController* ctrl_;  // weak

  DeviceAddress address_;
  std::string name_;
  bool connected_;
  bool connectable_;
  bool scannable_;
  bool advertising_enabled_;
  bool directed_;
  bool address_resolved_;

  hci::StatusCode connect_status_;
  hci::StatusCode connect_response_;
  bool force_pending_connect_;  // Causes connection requests to remain pending.

  hci::LEConnectionParameters le_params_;

  // If false, FakeController will send LE Connection Update complete events with status
  // kRemoteFeatureNotSupported.
  bool supports_ll_conn_update_procedure_;

  hci::LESupportedFeatures le_features_;

  bool should_batch_reports_;
  DynamicByteBuffer adv_data_;
  DynamicByteBuffer scan_rsp_;

  // Open connection handles.
  HandleSet logical_links_;

  // Class of device
  DeviceClass class_of_device_;

  FakeL2cap l2cap_;
  FakeGattServer gatt_server_;
  FakeSignalingServer signaling_server_;
  FakeSdpServer sdp_server_;
  DISALLOW_COPY_AND_ASSIGN_ALLOW_MOVE(FakePeer);
};

}  // namespace bt::testing

#endif  // SRC_CONNECTIVITY_BLUETOOTH_CORE_BT_HOST_TESTING_FAKE_PEER_H_