using System;
using System.Collections.Concurrent;
using ErsatzTV.Core.Interfaces.Locking;

namespace ErsatzTV.Infrastructure.Locking
{
    public class EntityLocker : IEntityLocker
    {
        private readonly ConcurrentDictionary<int, byte> _lockedLibraries;
        private readonly ConcurrentDictionary<Type, byte> _lockedRemoteMediaSourceTypes;
        private bool _plex;

        public EntityLocker()
        {
            _lockedLibraries = new ConcurrentDictionary<int, byte>();
            _lockedRemoteMediaSourceTypes = new ConcurrentDictionary<Type, byte>();
        }

        public event EventHandler OnLibraryChanged;
        public event EventHandler OnPlexChanged;
        public event EventHandler<Type> OnRemoteMediaSourceChanged;

        public bool LockLibrary(int libraryId)
        {
            if (!_lockedLibraries.ContainsKey(libraryId) && _lockedLibraries.TryAdd(libraryId, 0))
            {
                OnLibraryChanged?.Invoke(this, EventArgs.Empty);
                return true;
            }

            return false;
        }

        public bool UnlockLibrary(int libraryId)
        {
            if (_lockedLibraries.TryRemove(libraryId, out byte _))
            {
                OnLibraryChanged?.Invoke(this, EventArgs.Empty);
                return true;
            }

            return false;
        }

        public bool IsLibraryLocked(int libraryId) =>
            _lockedLibraries.ContainsKey(libraryId);

        public bool LockPlex()
        {
            if (!_plex)
            {
                _plex = true;
                OnPlexChanged?.Invoke(this, EventArgs.Empty);
                return true;
            }

            return false;
        }

        public bool UnlockPlex()
        {
            if (_plex)
            {
                _plex = false;
                OnPlexChanged?.Invoke(this, EventArgs.Empty);
                return true;
            }

            return false;
        }

        public bool IsPlexLocked() => _plex;

        public bool LockRemoteMediaSource<TMediaSource>()
        {
            Type mediaSourceType = typeof(TMediaSource);

            if (!_lockedRemoteMediaSourceTypes.ContainsKey(mediaSourceType) &&
                _lockedRemoteMediaSourceTypes.TryAdd(mediaSourceType, 0))
            {
                OnRemoteMediaSourceChanged?.Invoke(this, mediaSourceType);
                return true;
            }

            return false;
        }

        public bool UnlockRemoteMediaSource<TMediaSource>()
        {
            Type mediaSourceType = typeof(TMediaSource);

            if (_lockedRemoteMediaSourceTypes.TryRemove(mediaSourceType, out byte _))
            {
                OnRemoteMediaSourceChanged?.Invoke(this, mediaSourceType);
                return true;
            }

            return false;
        }
    }
}