oopbattery

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace MobilePhoneDevice
{
    class Battery
    {
        //const double DefaultHoursIdle = 4.0;
        //const double DefaultHoursTalk = 0.5;
        private string model;
        private double? hoursIdle = 4.0;  // !
        private double? hoursTalk = 0.5;// !
        public BatteryType BatteryType { get; set; }

        //property for model
        public string Model
        {
            get
            {
                return this.model;
            }
             set // ????
            {
                this.model = value;
            }
        }
          //property for hours idle
        public double? HoursIdle
        {
            get { return this.hoursIdle; }
             set // ????
            {
                if (value==null)
                {
                    //value = DefaultHoursIdle;
                    value = hoursIdle;
                }
                this.hoursIdle = value;
                if (hoursIdle < 0)
                {
                    throw new ArgumentException();
                }
            }
        }
        public double? HoursTalk
        {
            get { return this.hoursTalk; }
            set // ????
            {
                if (value == null)
                {
                    //value = DefaultHoursTalk;
                    value = hoursTalk;
                }
                this.hoursTalk = value;
                if (hoursTalk < 0)
                {
                    throw new ArgumentException();
                }
            }
        }
        //public Battery()
        //{
        //}

        //constructor
        public Battery(string model)
            : this(model, null, null, BatteryType.Liion)
        {

        }

        //constructor
        //public Battery(string model, double hoursTalk):this(model,null,hoursTalk,BatteryType.Liion)
        //{
        //}
        //constructor
        public Battery(string model, double? hoursIdle, double? hoursTalk, BatteryType batteryType)
        {
            this.Model = model;
            this.HoursIdle = hoursIdle;
            this.HoursTalk = hoursTalk;
            this.BatteryType = batteryType;
        }
        static void Main()
        {

            Battery battery = new Battery("varta");
            Console.WriteLine(battery.model);
            Console.WriteLine(battery.HoursIdle);
            Console.WriteLine(battery.hoursTalk);
            Console.WriteLine("--");
            Console.WriteLine();
            Battery ba = new Battery("toshiba", 40, 49, BatteryType.NiCd);
            Console.WriteLine(ba.Model);
            Console.WriteLine(ba.HoursTalk);
            Console.WriteLine(ba.HoursIdle);
        }
    }
}