dataframe/src/dataframe.h

/*
 * @file dataframe.h
 * @brief DataFrame interface
 *
 * @date: 31. 12. 2022
 * @author: juraj
 */

#ifndef __DATAFRAME_H__
#define __DATAFRAME_H__

#include "stdint.h"

#define HEADER_CHAR 0xCC

/**
 * @brief Class for representing data frame.
 */
class DataFrame{

private:
	uint8_t *_frame;
	uint8_t _length;
	uint8_t _capacity;

public:
	/**
	 * Constructor.
	 * @param frame pointer to existing byte array
	 * @param size size of buffer `frame`
	 */
	DataFrame(uint8_t *frame, uint8_t size);
	/**
	 * @brief Initialize packet
	 * - set the header of packet
	 * - reserver 1st byte to length of frame
	 */
	void Init(void);

	/**
	 * @brief Add one byte to data frame.
	 * @return true, if it is success
	 */
	bool AddUint8(uint8_t d);

	/**
	 * @brief add 2 Bytes length variable to dataframe
	 * @param d variable added to data frame
	 * @return true, if it is success
	 */
	bool AddUint16(uint16_t d);

	/**
	 * @brief add 4 Bytes long variable to dataframe
	 * @param d variable added to data frame
	 * @return true, if it is success
	 */
	bool AddUint32(uint32_t);

	/**
	 * @brief add one byte signed variable to data frame
	 * @param d variable added to data frame
	 * @return true, if it is success
	 */
	bool AddInt8(int8_t d);

	/**
	 * @brief add 2 bytes length signed variable to data frame
	 * @param d variable added to data frame
	 * @return true, if it is success
	 */
	bool AddInt16(int16_t);

	/**
	 * @brief add 4 bytes length signed variable to data frame
	 * @param d variable added to data frame
	 * @return true, if it is success
	 */
	bool AddInt32(int32_t);

	/**
	 * @brief add float value to data frame.
	 * Float value is encoded to 4 bytes according IEEE 754
	 * @param d variable added to data frame
	 * @return true, if it is success
	 */
	bool AddFloat(float);

	/**
	 * @brief Commit the creation of the packet.
	 * - add to second position (frame[1]) length of packet
	 * - compute CRC of packet
	 * @return real length of packet (including CRC byte)
	 */
	uint8_t Commit(void);

	/**
	 * @brief Return pointer to data frame.
	 * @return resulting packet
	 */
	uint8_t* GetFrame(void);
};

#ifdef __cplusplus
 extern "C" {
#endif

uint8_t crc8(uint8_t crc, uint8_t Size, uint8_t *Buffer);

#ifdef __cplusplus
}
#endif

#endif /* DATAFRAME_H_ */