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

namespace TeamsNetphoneLink.Communication
{
    public class TeamsGraphEventHandlers
    {
        private readonly object _lock = new object();
        private readonly List<EventHandler<PresenceChangedEventArgs>> _activityChangedHandlers = new List<EventHandler<PresenceChangedEventArgs>>();
        private readonly List<EventHandler<PresenceChangedEventArgs>> _availabilityChangedHandlers = new List<EventHandler<PresenceChangedEventArgs>>();

        public event EventHandler<PresenceChangedEventArgs> ActivityChanged
        {
            add
            {
                lock (_lock)
                {
                    _activityChangedHandlers.Add(value);
                }
            }
            remove
            {
                lock (_lock)
                {
                    _activityChangedHandlers.Remove(value);
                }
            }
        }

        public event EventHandler<PresenceChangedEventArgs> AvailabilityChanged
        {
            add
            {
                lock (_lock)
                {
                    _availabilityChangedHandlers.Add(value);
                }
            }
            remove
            {
                lock (_lock)
                {
                    _availabilityChangedHandlers.Remove(value);
                }
            }
        }

        protected void OnActivityChanged(Microsoft.Graph.Models.Presence presence)
        {
            lock (_lock)
            {
                var args = new PresenceChangedEventArgs(presence);
                foreach (var handler in _activityChangedHandlers)
                {
                    handler?.Invoke(this, args);
                }
            }
        }

        protected void OnAvailabilityChanged(Microsoft.Graph.Models.Presence presence)
        {
            lock (_lock)
            {
                var args = new PresenceChangedEventArgs(presence);
                foreach (var handler in _availabilityChangedHandlers)
                {
                    handler?.Invoke(this, args);
                }
            }
        }

        public void RemoveAllEventHandlers()
        {
            foreach (var handler in _activityChangedHandlers)
            {
                _availabilityChangedHandlers.Remove(handler);
            }
            foreach (var handler in _availabilityChangedHandlers)
            {
                _availabilityChangedHandlers.Remove(handler);
            }
        }
    }

    public class PresenceChangedEventArgs : EventArgs
    {
        public Microsoft.Graph.Models.Presence Presence { get; }

        public PresenceChangedEventArgs(Microsoft.Graph.Models.Presence presence)
        {
            Presence = presence;
        }
    }
}