/home/shenghao/eclipse-workspace/EV3UartProtocolParserSensorSide/EV3UartProtocolParserSensorSide.hpp

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#ifndef EV3UARTPROTOCOLPARSERSENSORSIDE_HPP_
#define EV3UARTPROTOCOLPARSERSENSORSIDE_HPP_

#include <magics.hpp>
#include <framing.hpp>

namespace EV3UartProtocolParserSensorSide {

constexpr uint8_t BUFFER_LEN { EV3UartGenerator::Framing::BUFFER_MIN };

constexpr uint8_t two_pow(uint8_t val) {
    return (0x01 << val);
}

enum class State : uint8_t {
    STATE_START = 0,    
    WAIT_HEADER = 0,    
    WAIT_CHECKSUM = 1,  
    STATE_END = 1,      
};

constexpr State next_state(State st) {
    if ((static_cast<uint8_t>(st))
            != (static_cast<uint8_t>(State::STATE_END)))
        return static_cast<State>(static_cast<uint8_t>(st) + 1);
    else
        return State::STATE_START;
}

enum class ParseResult : uint8_t {
    INSUFFICIENT_DATA,
    RECEIVED_INVALID_HEADER,
    RECEIVED_SYS_ACK,
    RECEIVED_SYS_NACK,
    RECEIVED_CMD_SELECT,
    RECEIVED_CMD_WRITE,
    RECEIVED_CMD_INVALID_FCS,
};

struct ParserReturn {
    ParseResult res; 
    uint8_t hdr;     
    uint8_t len;     
};

class Parser {
private:
    uint8_t buffer[BUFFER_LEN];
    uint8_t message_payload_length = 0;
    uint8_t message_pending_bytes = 0;
    State current_state = State::STATE_START;

    uint8_t payload_length(const uint8_t hdr);

    struct HeaderInformation {
        bool header_valid;
        uint8_t header_sanitized;
        uint8_t payload_length;
    };
    HeaderInformation analyze_header(const uint8_t hdr);
public:

    // We use the default constructor, because we don't really need to do
    // anything

    Parser();
    Parser(const Parser&) = delete;

    ParserReturn update(uint8_t input);

    uint8_t* data();

    const uint8_t* data() const;

    void reset_state();
};
}




#endif /* EV3UARTPROTOCOLPARSERSENSORSIDE_HPP_ */