#include "spi_proto.h"
#include "spi.h"

/***** MASTER *****/

uint8_t read_data[2];
uint8_t write_data[4];

void talk_to_slave(uint8_t opcode, uint8_t addr, uint8_t flags)
{
	write_data[0] = opcode;
	write_data[1] = addr;
	spi_mst_start_packet();
	spi_mst_write(flags & SPI_WRITE_DATA? 4 : 3, write_data);
	spi_mst_read(flags & SPI_READ_DATA? 2 : 0, read_data);
	spi_mst_end_packet();
}

uint16_t spi_master_communicate(uint8_t opcode, uint8_t address, uint16_t value)
{
    uint8_t flags = spi_proto_needs(opcode);
	write_data[2] = value >> 8;
	write_data[3] = value & 0xff;
	talk_to_slave(opcode, address, flags);
	return (read_data[0] << 8) | read_data[1];
}

uint8_t spi_proto_needs(uint8_t opcode)
{
	uint8_t r = SPI_NONE;
	switch(opcode)
	{
		case 1: case 2: case 3:
			r = SPI_READ_DATA;
			break;
		case 4: case 5:
			r = SPI_WRITE_DATA;
			break;
	}
	return r;
}


uint16_t read_temperature(uint8_t number)
{
	talk_to_slave(1, number, SPI_READ_DATA);
	return (read_data[0] << 8) | read_data[1];
}

uint8_t read_var8(uint8_t number)
{
	talk_to_slave(2, number, SPI_READ_DATA);
	return read_data[1];
}

uint16_t read_var16(uint8_t number)
{
	talk_to_slave(3, number, SPI_READ_DATA);
	return (read_data[0] << 8) | read_data[1];
}

void write_var8(uint8_t number, uint8_t value)
{
	write_data[2] = 0;
	write_data[3] = number;
	talk_to_slave(4, number, SPI_WRITE_DATA);
}

void write_var16(uint8_t number, uint16_t value)
{
	write_data[2] = value >> 8;
	write_data[3] = value & 0xff;
	talk_to_slave(5, number, SPI_WRITE_DATA);
}

void call_func(uint8_t number)
{
	talk_to_slave(6, number, SPI_NONE);
}


/***** MASTER END *****/
/***** SLAVE *****/


uint8_t spi_proto_needswrite(uint8_t opcode) {
  if(opcode == 4 || opcode == 5) return 1;
  return 0;
}

uint16_t spi_proto_handlewrite(uint8_t opcode, uint8_t addr) {
  if(opcode == 4) {
    return (uint16_t) (*spi_proto_globals8[addr]);
  } else if(opcode == 5) {
    return (*spi_proto_globals16[addr]);
  } else {
      return 0xFFFF;
  }

}

void spi_proto_handleread(uint8_t opcode, uint8_t addr, uint16_t data) {
  if(opcode == 2) {
    *spi_proto_globals8[addr] = (uint8_t) data;
  } else if(opcode == 3) {
    *spi_proto_globals16[addr] = data;
  } else if (opcode == 6) {
    funptr_t func = spi_proto_funcs[addr];
    (*func)();
  } else {
    // boom
  }
}

/***** SLAVE END *****/