#include "spi.h"
#include "registers.h"

void spi_init(spi_t* spi, SPI_TypeDef* peripheral, uint8_t idx) {
  spi->periph = peripheral;
  spi->idx = idx;
}

void spi_master_configure_speed(spi_t *spi,
                                uint8_t divider) {
  reg_write_bits(&spi->periph->CR1, divider << SPI_CR1_BR_Pos, SPI_CR1_BR_Msk);
}

void spi_master_configure(spi_t *spi, bool sw_nss, bool clock_polarity,
                          bool clock_phase, spi_frame_orientation_t orientation, spi_frame_format_t format) {
  reg_write_bits(&spi->periph->CR1,
                 (sw_nss << SPI_CR1_SSM_Pos) | (format << SPI_CR1_DFF_Pos) |
                     (orientation << SPI_CR1_LSBFIRST_Pos) |
                     (1 << SPI_CR1_BIDIMODE_Pos) | (1 << SPI_CR1_MSTR_Msk) |
                 (clock_polarity << SPI_CR1_CPOL_Msk) | (clock_phase << SPI_CR1_CPHA_Msk),
                 SPI_CR1_SSM_Msk | SPI_CR1_DFF_Msk | SPI_CR1_LSBFIRST_Msk | SPI_CR1_BIDIMODE_Msk | SPI_CR1_MSTR_Msk | SPI_CR1_CPOL_Msk | SPI_CR1_CPHA_Msk);
}
void spi_master_enable(spi_t *spi, bool enable) {
  reg_set_bits(&spi->periph->CR1, SPI_CR1_SPE);
}

uint16_t spi_transmit(spi_t *spi, uint16_t *data, uint16_t size) {
  for (int16_t i = 0; i < size; i++) {
    char byte = *(data++);

    while (!(spi->periph->SR & USART_SR_TXE));
    spi->periph->DR = byte;
  }

  return size;
}
uint16_t spi_receive(spi_t *spi, uint16_t *buffer, uint16_t max_size) {
  uint16_t size = 0;

  while (size < max_size - 1 && (spi->periph->SR & USART_SR_RXNE)) {
    *(buffer + (size++)) = (char)(spi->periph->DR & USART_DR_DR_Msk);
  }

  return size;

}

bool spi_can_transmit(spi_t *spi) {
  return (spi->periph->SR & SPI_SR_TXE) != 0;
}
bool spi_can_receive(spi_t *spi) {
  return (spi->periph->SR & SPI_SR_RXNE) != 0;

}