//*****************************************************************************
// uart.c
//*****************************************************************************

#include <pic.h>
#include "uart.h"
#include "motor_control.h"
#include "lcd.h"

uint8_t rx_data[RX_BUFF_SIZE];
uint8_t rx_timeout = 0;
uint8_t rx_cnt = 0;
uint8_t rx_done_flag = 0;
uint8_t rx_cnt_en = 0;
uint8_t tx_data[16];

const uint8_t event_set[] = "SET";
const uint8_t event_get[] = "GET";
const uint8_t param_spd[] = "SPD";
const uint8_t param_dir[] = "DIR";
const uint8_t param_run[] = "RUN";

#define EVENT_SET   2
#define EVENT_GET   1
#define PARAM_SPD   1
#define PARAM_DIR   2
#define PARAM_RUN   3

//called every 23.4ms
void uart_task(void)
{
    if(rx_cnt_en)
    {
        rx_timeout++;
    }
    if(rx_timeout > 1) //about 25-50ms
    {
        //rx done
        rx_timeout = 0;
        rx_done_flag = 1;
        rx_cnt_en = 0;
        rx_cnt = 0;
    }

    //process received data
    if(rx_done_flag)
    {
        uart_parse();
        rx_done_flag = 0;
    }
}

void uart_parse(void)
{
  /*  uint8_t events[32];
    uint8_t parameters[64];
    int parameter_tmp[2];
    sscanf(rx_data, "[%[^]]]{%[^}]}", &events, &parameters);*/

    //had to write very simple parser, as XC8 compiler sucks
    uint8_t str_pointer = 0;
    uint8_t event = 0;
    uint8_t param = 0;
    uint16_t value = 0;
    uint8_t tx_lenght = 0;

    uint8_t parse_lock = 2;

    //parse event type
    while(str_pointer < 4)
    {
        if(rx_data[str_pointer] == event_set[str_pointer] && parse_lock >= EVENT_SET)
        {
            parse_lock = EVENT_SET;
            if(str_pointer == 2) //if pointer goes thru all 3 chars, then event is valid
            {
                event = EVENT_SET;
                break;
            }
        }
        else if (rx_data[str_pointer] == event_get[str_pointer] && parse_lock >= EVENT_GET)
        {
            parse_lock = EVENT_GET;
            if(str_pointer == 2)
            {
                event = EVENT_GET;
                break;
            }
        }
        str_pointer++;
    }
    //event not valid, parsing failed
    if(event == 0)
        return;

    str_pointer = 0;

    //parse param
    while(str_pointer < 4)
    {
        if(rx_data[str_pointer+4] == param_spd[str_pointer])
        {
            if(str_pointer == 2) //if pointer goes thru all 3 chars, then event is valid
            {
                param = PARAM_SPD;
                break;
            }
        }
        else if (rx_data[str_pointer+4] == param_dir[str_pointer])
        {
            if(str_pointer == 2)
            {
                param = PARAM_DIR;
                break;
            }
        }
        else if (rx_data[str_pointer+4] == param_run[str_pointer])
        {
            if(str_pointer == 2)
            {
                param = PARAM_RUN;
                break;
            }
        }
        str_pointer++;
    }

    //param not valid, parsing failed
    if(event == 0)
        return;

    str_pointer = 0;

    //parse value
    value = atoi(rx_data + 8);

    //send back info
    if(event == EVENT_GET)
    {
        switch(param)
        {
            case PARAM_SPD:
                tx_lenght = sprintf(tx_data, "PUSH.SPD:%d\n", motor1.rpm * 10);
                uart_sendString(tx_data, tx_lenght);
                break;
            case PARAM_DIR:
                if(motor1.direction == DIR_FW)
                    tx_lenght = sprintf(tx_data, "PUSH.DIR:FW\n");
                else
                    tx_lenght = sprintf(tx_data, "PUSH.DIR:RW\n");
                uart_sendString(tx_data, tx_lenght);
                break;
            case PARAM_RUN:
                tx_lenght = sprintf(tx_data, "PUSH.RUN:%d\n", motor1.running);
                uart_sendString(tx_data, tx_lenght);
                break;
            default:
                tx_lenght = sprintf(tx_data, "UNRECOGNIZED\n", motor1.running);
                uart_sendString(tx_data, tx_lenght);
        }
    }
    else if (event == EVENT_SET)
    {
        switch(param)
        {
            case PARAM_SPD:
                motor1.pwm = map(value,0,1000,120,1023);
                break;
            case PARAM_DIR:
                motor1.direction = value;
                break;
            case PARAM_RUN:
                motor1.running = value;
                break;
        }
        motor1.st_change = 1;
    }

}

void uart_callback(void)
{
    rx_cnt_en = 1; //start timeout counter
    rx_timeout = 0;
    rx_data[rx_cnt] = RCREG;
    rx_cnt++;
    //if(rx_cnt > 31) //TODO
        //buffer overflow
}

// init UART for 8MHz
void uart_init(void)
{
    SPBRG = 12; //9600bps, 8MHz
    TXSTAbits.BRGH = 0;
    TXSTAbits.SYNC = 0;
    RCSTAbits.SPEN = 1;
    TXSTAbits.TX9 = 0;
    TXSTAbits.TXEN = 1;
    PIE1bits.RCIE = 1; //enable interrupt for receiver
    RCSTAbits.CREN = 1;

}

// send one byte by UART
void  uart_putChar(char data)
{
    while(!TXSTAbits.TRMT); //wait if transimt register is full
    TXREG = data;
}

void uart_sendString(char* string, int lenght)
{
    int i = 0;
    for (i; i < lenght; i++)
    {
        uart_putChar(*string);
        *string++;
    }
}