#include "stm32f0xx_hal.h"

#include "config.h"
#include "stringhelpers.h"
#include "states.h"
#include "gpio.h"

// Grab temperature reading from MAX31865
void max31865_readtemp(SPI_HandleTypeDef* hspi1, therm_settings_t* set, therm_status_t* status)
{
    // ** FIXME ** FIXME ** FIXME ** //
    // This is duplicated from MAX31855, update for MAX31865 registers/etc
    /////////////////////////////////// 

    // Assert CS
    HAL_GPIO_WritePin(MAX_CS, 0);

    uint8_t rxdatah[1] = {0x00};
    uint8_t rxdatal[1] = {0x00};

    HAL_SPI_Receive(hspi1, rxdatah, 1, 100);
    HAL_SPI_Receive(hspi1, rxdatal, 1, 100);

    // Release CS
    HAL_GPIO_WritePin(MAX_CS, 1);

    // Assemble data array into one var
    uint16_t temp_pre = rxdatal[0] | (rxdatah[0]<<8);
    if(temp_pre & 0b001 && !set->ignore_tc_error) {
        status->tc_errno = 1;
        HAL_Delay(400); // FIXME: remove?
        status->state_resume = status->state;
        status->state = STATE_TC_ERROR;
        status->temp = 0;
        status->temp_frac = 0;
    }
    else 
    {
        uint8_t sign = status->temp >> 15;// top bit is sign
        temp_pre = temp_pre >> 2; // Drop 2 lowest bits
        status->temp_frac = temp_pre & 0b11; // get fractional part
        status->temp_frac *= 25; // each bit is .25 a degree, up to fixed point
        temp_pre = temp_pre >> 2; // Drop 2 fractional bits 

        int8_t signint;

        if(sign) {
            signint = -1;
        }
        else {
            signint = 1;
        }

        // Convert to Fahrenheit
        if(set->temp_units == TEMP_UNITS_FAHRENHEIT)
        {
            status->temp = signint * ((temp_pre*100) + status->temp_frac);
            status->temp = status->temp * 1.8;
            status->temp += 3200;
            status->temp_frac = status->temp % 100;
            status->temp /= 100;
            status->temp += set->temp_offset;
        }

        // Use Celsius values
        else
        {
            status->temp = temp_pre * signint;
            status->temp += set->temp_offset;
        }
    }
}

// vim:softtabstop=4 shiftwidth=4 expandtab