// 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_HCI_ADVERTISING_REPORT_PARSER_H_
#define SRC_CONNECTIVITY_BLUETOOTH_CORE_BT_HOST_HCI_ADVERTISING_REPORT_PARSER_H_

#include <fbl/macros.h>

#include "src/connectivity/bluetooth/core/bt-host/hci-spec/protocol.h"
#include "src/connectivity/bluetooth/core/bt-host/hci/control_packets.h"

namespace bt::hci {

// Convenience class for extracting the contents of a HCI LE Advertising Report
// Event.
class AdvertisingReportParser final {
 public:
  // |event| must represent a LE Meta Event containing a LE Advertising Report
  // sub-event. The buffer that backs |event| must remain valid for the duration
  // in which this parser instance will be used.
  explicit AdvertisingReportParser(const EventPacket& event);

  // Returns the next LE Advertising report contained in this event in
  // |out_data| and the RSSI in |out_rssi|. Returns false if there were no
  // more reports to return or if a report is malformed.
  bool GetNextReport(const LEAdvertisingReportData** out_data, int8_t* out_rssi);

  // Returns true if there are more reports to process.
  bool HasMoreReports();

  // Returns true if the parsing stopped due to malformed packet contents. This
  // is only possible in the very rare scenario in which the controller sent us
  // a payload that could not be parsed correctly.
  //
  // Users should check this after iterating through the reports to make sure
  // there was no error and avoid any further processing if necessary. This flag
  // will be lazily set if-and-only-if GetNextReport() or HasMoreReports()
  // returns false due to a parse error.
  bool encountered_error() const { return encountered_error_; }

 private:
  // True if we encountered an error while parsing the report.
  bool encountered_error_;

  // The number remaining reports that have not been processed via a call to
  // GetNextReport.
  uint8_t remaining_reports_;

  // Number of unprocessed bytes left in the report.
  size_t remaining_bytes_;

  // Pointer to the beginning of the next advertising report segment.
  const uint8_t* ptr_;

  DISALLOW_COPY_AND_ASSIGN_ALLOW_MOVE(AdvertisingReportParser);
};

}  // namespace bt::hci

#endif  // SRC_CONNECTIVITY_BLUETOOTH_CORE_BT_HOST_HCI_ADVERTISING_REPORT_PARSER_H_