portapack-mayhem/firmware/common/tpms_packet.hpp

/*
 * Copyright (C) 2015 Jared Boone, ShareBrained Technology, Inc.
 * Copyright (C) 2023 Mark Thompson
 *
 * This file is part of PortaPack.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street,
 * Boston, MA 02110-1301, USA.
 */

#ifndef __TPMS_PACKET_H__
#define __TPMS_PACKET_H__

#include <cstdint>
#include <cstddef>

#include "optional.hpp"

#include "units.hpp"
using units::Pressure;
using units::Temperature;

#include "baseband_packet.hpp"
#include "manchester.hpp"
#include "field_reader.hpp"

namespace tpms {

using Flags = uint8_t;

enum SignalType {
    FSK_19k2_Schrader = 1,
    OOK_8k192_Schrader = 2,
    OOK_8k4_Schrader = 3,
};

class TransponderID {
   public:
    constexpr TransponderID()
        : id_{0} {
    }

    constexpr TransponderID(
        const uint32_t id)
        : id_{id} {
    }

    constexpr uint32_t value() const {
        return id_;
    }

    constexpr bool operator==(const TransponderID& other) const {
        return id_ == other.id_;
    }

   private:
    uint32_t id_;
};

class Reading {
   public:
    enum Type {
        None = 0,
        FLM_64 = 1,
        FLM_72 = 2,
        FLM_80 = 3,
        Schrader = 4,
        GMC_96 = 5,
    };

    constexpr Reading()
        : type_{Type::None} {
    }

    constexpr Reading(
        Type type,
        TransponderID id)
        : type_{type},
          id_{id} {
    }

    constexpr Reading(
        Type type,
        TransponderID id,
        Optional<Pressure> pressure = {},
        Optional<Temperature> temperature = {},
        Optional<Flags> flags = {})
        : type_{type},
          id_{id},
          pressure_{pressure},
          temperature_{temperature},
          flags_{flags} {
    }

    Type type() const {
        return type_;
    }

    TransponderID id() const {
        return id_;
    }

    Optional<Pressure> pressure() const {
        return pressure_;
    }

    Optional<Temperature> temperature() const {
        return temperature_;
    }

    Optional<Flags> flags() const {
        return flags_;
    }

   private:
    Type type_{Type::None};
    TransponderID id_{0};
    Optional<Pressure> pressure_{};
    Optional<Temperature> temperature_{};
    Optional<Flags> flags_{};
};

class Packet {
   public:
    constexpr Packet(
        const baseband::Packet& packet,
        const SignalType signal_type)
        : packet_{packet},
          signal_type_{signal_type},
          decoder_{packet_, 0},
          reader_{decoder_} {
    }

    SignalType signal_type() const { return signal_type_; }
    Timestamp received_at() const;

    FormattedSymbols symbols_formatted() const;

    Optional<Reading> reading() const;

   private:
    using Reader = FieldReader<ManchesterDecoder, BitRemapNone>;

    const baseband::Packet packet_;
    const SignalType signal_type_;
    const ManchesterDecoder decoder_;

    const Reader reader_;

    Optional<Reading> reading_fsk_19k2_schrader() const;
    Optional<Reading> reading_ook_8k192_schrader() const;
    Optional<Reading> reading_ook_8k4_schrader() const;

    size_t crc_valid_length() const;
};

} /* namespace tpms */

#endif /*__TPMS_PACKET_H__*/