using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Tango.Core;
using Tango.PMR.Power;

namespace Tango.Integration.Operation
{
    public class PowerDownHandler : ExtendedObject
    {
        private Task _abortTask;

        public event EventHandler<PowerDownStatusChangedEventArgs> StatusChanged;
        public event EventHandler<Exception> Failed;
        public event EventHandler Completed;

        private StartPowerDownResponse _status;
        public StartPowerDownResponse Status
        {
            get { return _status; }
            set { _status = value; RaisePropertyChangedAuto(); }
        }

        internal PowerDownHandler(Task abortTask)
        {
            _abortTask = abortTask;

            Status = new StartPowerDownResponse()
            {
                Message = "Powering down...",
                State = PowerDownState.None,
            };
        }

        internal void RaiseStatusChanged(StartPowerDownResponse status)
        {
            OnStatusChanged(status);
        }

        internal void RaiseFailed(Exception ex)
        {
            OnFailed(ex);
        }

        internal void RaiseCompleted()
        {
            OnCompleted();
        }

        private void OnStatusChanged(StartPowerDownResponse status)
        {
            Status = status;
            StatusChanged?.Invoke(this, new PowerDownStatusChangedEventArgs()
            {
                Status = status
            });
        }

        private void OnCompleted()
        {
            Completed?.Invoke(this, new EventArgs());
        }

        private void OnFailed(Exception ex)
        {
            Failed?.Invoke(this, ex);
        }

        public async Task Abort()
        {
            _abortTask.Start();
            await _abortTask;
        }
    }
}