/* RS232/TTL/RS485 communication
 * comport.c
 *
 *  Created on: Feb 15, 2023
 *      Author: Think
 */

#include "comport.h"
#include "miscdev.h"

//#define CONFIG_COMPORT_DEBUG

#ifdef  CONFIG_COMPORT_DEBUG
#define com_print(format,args...) printf(format, ##args)
#else
#define com_print(format,args...) do{} while(0)
#endif

#define ARRAY_SIZE(x)   sizeof(x)/sizeof(x[0])

comport_t  comports[] = {
		{.fd=-1, .devname="WiFi",  .huart=&huart2   }, // ESP8266(WiFi)/ESP32(WiFi/BLE)
		{.fd=-1, .devname="RS232", .huart=&huart3   }, // RS232/TTL/MikroBUS
		{.fd=-1, .devname="RS485", .huart=&hlpuart1 }, // RS485
};


static inline comport_t *comport_find(UART_HandleTypeDef *huart)
{
	comport_t              *comport = NULL;
	int                     i;

	for(i=0; i<ARRAY_SIZE(comports); i++)
	{
		if( huart==comports[i].huart )
		{
			comport = &comports[i];
		}
	}

	return comport;
}

comport_t *comport_init(UART_HandleTypeDef *huart, uint8_t *rxch, uint8_t *rxbuf, size_t size)
{
	comport_t              *comport = NULL;

	if( !huart )
		return NULL;

	/* Find the corresponding comport in the array */
	comport = comport_find(huart);
	if( !comport )
		return NULL;

	comport->fd = 1;
	comport->huart = huart;
	comport->rxch = rxch;
	rb_init(&comport->rb, rxbuf, size);

	return comport;
}


/* +----------------------------------------+
 * | printf and interrupt receive functions |
 * +----------------------------------------+*/

/* printf callback function on USART1 */
int __io_putchar(int ch)
{
	HAL_UART_Transmit(&huart1 , (uint8_t *)&ch, 1, 0xFFFF);
	return ch;
}

/* USART interrupt receive callback funciton */
void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)
{
	comport_t              *comport = NULL;
	uint8_t                 byte;

	/* Find the corresponding comport in the array */
	comport = comport_find(huart);
	if( !comport )
	{
		goto cleanup;
	}

	/* Check comport receive ring buffer */
	if( comport->fd<0 || !comport->rb.buffer || ! rb_free_size(&comport->rb) )
	{
		goto cleanup;
	}

	/* Receive and put the byte into receive ring buffer */
	HAL_UART_Receive_IT(comport->huart, comport->rxch, 1);
	rb_write(&comport->rb, comport->rxch, 1);

	return ;

cleanup:
	HAL_UART_Receive_IT(huart, &byte, 1);
	return ;
}

/* +------------------------+
 * | UART/TTL API functions |
 * +------------------------+*/

comport_t *comport_open(UART_HandleTypeDef *huart)
{
	comport_t              *comport = NULL;

	if( !huart )
		return NULL;

	/* Find the corresponding comport in the array */
	comport = comport_find(huart);
	if( comport )
		comport->fd = 1;

	return comport;
}

void comport_flush(comport_t *comport)
{
	if( !comport || !comport->huart)
		return;

	if( comport->rb.buffer )
	{
		rb_clear( &comport->rb );
	}

	return;
}

void comport_term(comport_t *comport)
{
	if( !comport || !comport->huart)
		return;

	comport->fd = -1;

	if( comport->rb.buffer )
	{
		rb_clear( &comport->rb );
	}

	return;
}

int comport_send(comport_t *comport, char *data, int bytes)
{
	if( !comport || !data || bytes<=0 )
		return -1;

	com_print("Send %d bytes data: %s\r\n", bytes, data);
	HAL_UART_Transmit(comport->huart, (uint8_t *)data, bytes, 0xFFFF);

	return bytes;
}

int comport_recv(comport_t *comport, char *buf, int size, uint32_t timeout)
{
	uint32_t          tickstart = 0;
	size_t            bytes = 0; 

	if( !comport || !buf || size<=0 )
		return -1;

	if( !comport->rb.buffer )
		return -2;

	tickstart = HAL_GetTick();

	while((HAL_GetTick() - tickstart) < timeout)
	{
		bytes = rb_data_size(&comport->rb);

		HAL_Delay( 10 );

		/* comport received data before but not receive in 10ms now, maybe data receive over */
		if( bytes>0 && rb_data_size(&comport->rb)==bytes )
		{
			break;
		}
	}

	bytes = rb_data_size(&comport->rb);
	if( !bytes )
	{
		return 0;
	}

	bytes = bytes>size ? size : bytes;
	rb_read(&comport->rb, (uint8_t *)buf, bytes);
	com_print("Receive %d bytes data: %s\r\n", bytes, buf);

	return bytes;
}


/* +------------------------+
 * |   RS485 API functions  |
 * +------------------------+*/

/* Direction Pin set to be high level will be send mode, and low level will be receive mode */
#define rs485_set_dirTx()   HAL_GPIO_WritePin(RS485_Dir_GPIO_Port, RS485_Dir_Pin, GPIO_PIN_SET)
#define rs485_set_dirRx()   HAL_GPIO_WritePin(RS485_Dir_GPIO_Port, RS485_Dir_Pin, GPIO_PIN_RESET)

comport_t *rs485_open(UART_HandleTypeDef *huart)
{
	return comport_find(huart);
}

void rs485_term(comport_t *comport)
{
	return comport_term(comport);
}

int rs485_send(comport_t *comport, char *data, int bytes)
{
	int             rv;

	rs485_set_dirTx();
	rv = comport_send(comport, data, bytes);

	rs485_set_dirRx();
	return rv;
}

int rs485_recv(comport_t *comport, char *buf, int size, uint32_t timeout)
{
	rs485_set_dirRx();

	return comport_recv(comport, buf, size, timeout);
}