/*
 * CBus.c
 *
 *  Created on: Jun 14, 2021
 *      Author: angoosh
 */
#include "CBus.h"

void ReadRxBuffer();
void SendPacket();

uint8_t ptr = 0;
uint8_t RX[1];
uint8_t WholeRxBuffer[RX_BUFFER_SIZE];

CBusPacket RxPacket;
CBusPacket TxPacket;
uint8_t CBusBufTx[64];
uint8_t CBusBufTxSize;

void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart){
	WholeRxBuffer[ptr] = RX[0];
	ptr++;
	//CLEAR_BIT(huart->Instance->ISR,USART_ISR_RXNE);
	HAL_UART_Receive_IT(&huart3, RX, 1);
}

void CBusBA(uint8_t byte){
#ifdef PREFIXINPACKETACTION
	if(byte == PREFIX){
		CBusBufTx[CBusBufTxSize++] = 0xBB;
		CBusBufTx[CBusBufTxSize++] = 0xBC;
	}
	else if(byte == 0xBB){
		CBusBufTx[CBusBufTxSize++] = 0xBB;
		CBusBufTx[CBusBufTxSize++] = 0xBB;
	}
	else{
		CBusBufTx[CBusBufTxSize++] = byte;
	}
#else
	CBusBufTx[CBusBufTxSize++] = byte;
#endif
}

void ReadRxBuffer(){
	uint8_t packtStart = 0;

	for(int l = 0; l<sizeof(WholeRxBuffer); l++){
		if(packtStart){
			packtStart = 0;
			uint8_t PCrc = 0;

			PCrc ^= RxPacket.RxAddr;
			PCrc ^= RxPacket.Length = WholeRxBuffer[l+1];
			PCrc ^= RxPacket.Sender = WholeRxBuffer[l+2];
			PCrc ^= RxPacket.Command = WholeRxBuffer[l+3];
			for(int i = 0; i < RxPacket.Length-5; i++){
				PCrc ^= RxPacket.Data[i] = WholeRxBuffer[l+4+i];
			}
			RxPacket.Crc = WholeRxBuffer[l+RxPacket.Length-1];
			if(PCrc == RxPacket.Crc){
				if(RxPacket.Command == TEST_CMD){
					HAL_GPIO_WritePin(GPIOD,LED_ERROR_Pin,RxPacket.Data[0]);
					TxPacket.RxAddr = RxPacket.Sender;
					TxPacket.Length = 6;
					TxPacket.Sender = ADDRESS;
					TxPacket.Command = ACK;
					TxPacket.Data[0] = RxPacket.Command;
					SendPacket();
				}
				l += RxPacket.Length;
			}
		}

		if(WholeRxBuffer[l] == PREFIX){
			RxPacket.RxAddr = WholeRxBuffer[l+1];
			if(RxPacket.RxAddr == ADDRESS){
				packtStart = 1;
			}
		}
	}
	for(int k = 0; k<sizeof(WholeRxBuffer); k++){
		WholeRxBuffer[k] = 0;
	}
	ptr = 0;
}

void SendPacket(){
	CBusBufTx[CBusBufTxSize++] = PREFIX;
	CBusBA(TxPacket.RxAddr);TxPacket.Crc ^= TxPacket.RxAddr;
	CBusBA(TxPacket.Length);TxPacket.Crc ^= TxPacket.Length;
	CBusBA(TxPacket.Sender);TxPacket.Crc ^= TxPacket.Sender;
	CBusBA(TxPacket.Command);TxPacket.Crc ^= TxPacket.Command;
	for(int i = 0; i<TxPacket.Length-5; i++){
		CBusBA(TxPacket.Data[i]);TxPacket.Crc ^= TxPacket.Data[i];
	}
	CBusBA(TxPacket.Crc);

	HAL_UART_Transmit(&huart3, CBusBufTx, CBusBufTxSize, 0xFFFF);
	CBusBufTxSize = 0;
	for(int i = 0; i < sizeof(CBusBufTx); i++){
		CBusBufTx[i] = 0;
	}

	memset(&TxPacket, 0, sizeof(TxPacket));
	memset(&RxPacket, 0, sizeof(RxPacket));
}