#include <Wire.h>
#include "Pca9554.h"

enum class Pca9554_Registers : uint8_t {
  INPUT_PORT         = 0x00,
  OUTPUT_PORT        = 0x01,
  POLARITY_INVERSION = 0x02,
  CONFIGURATION      = 0x03,
};

Pca9554::Pca9554(uint8_t slaveAddress) :
  outputValues { 0 }, slaveAddress { slaveAddress }, inputMask { 0 }
{

}

Pca9554::~Pca9554()
{

}

void Pca9554::begin(uint8_t inputMask, uint8_t outputs)
{
  SetInputPins(inputMask);
  SendOutputValues(outputValues = outputs);
}

void Pca9554::SetInputPins(uint8_t inputMask)
{
  this->inputMask = inputMask;
  Wire.beginTransmission(slaveAddress | 0x00);
  Wire.write((uint8_t) Pca9554_Registers::CONFIGURATION);
  Wire.write(inputMask);
  Wire.endTransmission();
}

uint8_t Pca9554::ReadInputs()
{
  Wire.beginTransmission(slaveAddress | 0x01);
  int result = Wire.read() & inputMask;
  Wire.endTransmission();
  return (uint8_t) result;
}

void Pca9554::SendOutputValues()
{
  SendOutputValues(outputValues);
}

void Pca9554::SendOutputValues(uint8_t values)
{
  Wire.beginTransmission(slaveAddress | 0x00);
  Wire.write((uint8_t) Pca9554_Registers::OUTPUT_PORT);
  Wire.write(values & ~inputMask);
  Wire.endTransmission();
}