using System.IO.Ports;
using System.Text;

namespace RGBController2.Boards
{
    /// <summary>
    /// ArduinoBoard used for communicating with a sigle Arduino device.
    /// </summary>
    public class ArduinoBoard : IBoard
    {
        /// <summary>
        /// True is communication has been established with the Arduino, false otherwise.
        /// </summary>
        public bool Connected { get; }

        /// <summary>
        /// The serial port object for communicating with the Arduino.
        /// </summary>
        private SerialPort _serialPort;

        /// <summary>
        /// Constructs an ArduinoBoard object for controlling the Arduino.
        /// </summary>
        /// <param name="portName">The COM port name of the arduino.</param>
        /// <param name="baudRate">The baud rate at which to communicate with the arduion. Default 9600.</param>
        public ArduinoBoard(string portName, int baudRate = 9600)
        {
            Connected = false;
            _serialPort = new SerialPort();
            _serialPort.PortName = portName;
            _serialPort.BaudRate = baudRate;
            _serialPort.Open();
            if (_serialPort.IsOpen)
                Connected = true;
        }

        /// <summary>
        /// Sets all of the LEDs to the chosen RGB colour.
        /// </summary>
        /// <param name="red">The red value</param>
        /// <param name="green">The green value</param>
        /// <param name="blue">The blue value</param>
        public void SetAllLeds(byte red, byte green, byte blue)
        {
            string command = "a";
            command += ByteToHexString(red);
            command += ByteToHexString(green);
            command += ByteToHexString(blue);
            command += ';';
            _serialPort.WriteLine(command);
        }

        /// <summary>
        /// Turns off all of the LEDs connected to the board. 
        /// </summary>
        public void TurnOffAllLeds()
        {
            string command = "a000000;";
            _serialPort.WriteLine(command);
        }

        /// <summary>
        /// Helper function to convert as byte to a hex string used by the arduino.
        ///     e.g: 255 would become FF
        /// </summary>
        /// <param name="b">The byte to be converted.</param>
        /// <returns></returns>
        private static string ByteToHexString(byte b)
        {
            StringBuilder hex = new StringBuilder(2);
            hex.AppendFormat("{0:x2}", b);
            return hex.ToString();
        }
    }
}