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#ifndef MaximInterfaceDevices_DS18B20
#define MaximInterfaceDevices_DS18B20

#include <MaximInterfaceCore/array_span.hpp>
#include <MaximInterfaceCore/SelectRom.hpp>
#include <MaximInterfaceCore/Sleep.hpp>
#include "Config.hpp"

namespace MaximInterfaceDevices {

/// @brief DS18B20 Programmable Resolution 1-Wire Digital Thermometer
/// @details The DS18B20 digital thermometer provides 9-bit to 12-bit
/// Celsius temperature measurements and has an alarm function with
/// nonvolatile user-programmable upper and lower trigger points. The
/// DS18B20 communicates over a 1-Wire bus that by definition requires
/// only one data line (and ground) for communication with a central
/// microprocessor. In addition, the DS18B20 can derive power directly
/// from the data line ("parasite power"), eliminating the need for an
/// external power supply.
class DS18B20 {
public:
  enum ErrorValue { CrcError = 1, DataError };

  static const uint_least8_t nineBitResolution = 0x1F;
  static const uint_least8_t tenBitResolution = 0x3F;
  static const uint_least8_t elevenBitResolution = 0x5F;
  static const uint_least8_t twelveBitResolution = 0x7F;

  /// Holds the contents of the device scratchpad.
  typedef Core::array_span<uint_least8_t, 8> Scratchpad;

  DS18B20(Core::Sleep & sleep, Core::OneWireMaster & master,
          const Core::SelectRom & selectRom)
      : selectRom(selectRom), master(&master), sleep(&sleep), resolution(0) {}

  void setSleep(Core::Sleep & sleep) { this->sleep = &sleep; }

  void setMaster(Core::OneWireMaster & master) { this->master = &master; }

  void setSelectRom(const Core::SelectRom & selectRom) {
    this->selectRom = selectRom;
  }

  /// Initializes the device for first time use.
  MaximInterfaceDevices_EXPORT Core::error_code initialize();

  /// @brief Write Scratchpad Command
  /// @details If the result of a temperature measurement is higher
  /// than TH or lower than TL, an alarm flag inside the device is
  /// set. This flag is updated with every temperature measurement.
  /// As long as the alarm flag is set, the DS1920 will respond to
  /// the alarm search command.
  /// @param[in] th 8-bit upper temperature threshold, MSB indicates sign.
  /// @param[in] tl 8-bit lower temperature threshold, LSB indicates sign.
  /// @param[in] res Resolution of the DS18B20.
  MaximInterfaceDevices_EXPORT Core::error_code
  writeScratchpad(uint_least8_t th, uint_least8_t tl, uint_least8_t res);

  /// @brief Read Scratchpad Command
  /// @param[out] scratchpad Contents of scratchpad.
  MaximInterfaceDevices_EXPORT Core::error_code
  readScratchpad(Scratchpad::span scratchpad);

  /// @brief Copy Scratchpad Command
  /// @details This command copies from the scratchpad into the
  /// EEPROM of the DS18B20, storing the temperature trigger bytes
  /// and resolution in nonvolatile memory.
  MaximInterfaceDevices_EXPORT Core::error_code copyScratchpad();

  /// @brief Read Power Supply command
  /// @details This command determines if the DS18B20 is parasite
  /// powered or has a local supply
  /// @param[out] localPower
  /// True if the device is powered by a local power supply, or false if the
  /// device is parasitically powered.
  MaximInterfaceDevices_EXPORT Core::error_code
  readPowerSupply(bool & localPower);

  /// @brief Convert Temperature Command
  /// @details This command begins a temperature conversion.
  MaximInterfaceDevices_EXPORT Core::error_code convertTemperature();

  /// @brief Recall Command
  /// @details This command recalls the temperature trigger values
  /// and resolution stored in EEPROM to the scratchpad.
  MaximInterfaceDevices_EXPORT Core::error_code recallEeprom();

  MaximInterfaceDevices_EXPORT static const Core::error_category &
  errorCategory();

private:
  Core::SelectRom selectRom;
  Core::OneWireMaster * master;
  const Core::Sleep * sleep;
  uint_least8_t resolution;
};

/// @brief Reads the current temperature as an integer value with decimal.
/// @param ds18b20 Device to read.
/// @param[out] temperature Temperature in degrees Celsius multiplied by 16.
MaximInterfaceDevices_EXPORT Core::error_code
readTemperature(DS18B20 & ds18b20, int & temperature);

inline Core::error_code make_error_code(DS18B20::ErrorValue e) {
  return Core::error_code(e, DS18B20::errorCategory());
}

} // namespace MaximInterfaceDevices

#endif