Implement syncplay backend

Emby.Server.Implementations/Syncplay/SyncplayManager.cs

@@ -0,0 +1,248 @@
+using System;
+using System.Collections.Concurrent;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading;
+using Microsoft.Extensions.Logging;
+using MediaBrowser.Controller.Library;
+using MediaBrowser.Controller.Session;
+using MediaBrowser.Controller.Syncplay;
+using MediaBrowser.Model.Syncplay;
+
+namespace Emby.Server.Implementations.Syncplay
+{
+    /// <summary>
+    /// Class SyncplayManager.
+    /// </summary>
+    public class SyncplayManager : ISyncplayManager, IDisposable
+    {
+        /// <summary>
+        /// The logger.
+        /// </summary>
+        private readonly ILogger _logger;
+
+        /// <summary>
+        /// The session manager.
+        /// </summary>
+        private readonly ISessionManager _sessionManager;
+
+        /// <summary>
+        /// The map between users and groups.
+        /// </summary>
+        private readonly ConcurrentDictionary<string, ISyncplayController> _userToGroupMap =
+            new ConcurrentDictionary<string, ISyncplayController>(StringComparer.OrdinalIgnoreCase);
+
+        /// <summary>
+        /// The groups.
+        /// </summary>
+        private readonly ConcurrentDictionary<string, ISyncplayController> _groups =
+        new ConcurrentDictionary<string, ISyncplayController>(StringComparer.OrdinalIgnoreCase);
+
+        private bool _disposed = false;
+
+        public SyncplayManager(
+            ILogger<SyncplayManager> logger,
+            ISessionManager sessionManager)
+        {
+            _logger = logger;
+            _sessionManager = sessionManager;
+
+            _sessionManager.SessionEnded += _sessionManager_SessionEnded;
+            _sessionManager.PlaybackStopped += _sessionManager_PlaybackStopped;
+        }
+
+        /// <summary>
+        /// Gets all groups.
+        /// </summary>
+        /// <value>All groups.</value>
+        public IEnumerable<ISyncplayController> Groups => _groups.Values;
+
+        /// <inheritdoc />
+        public void Dispose()
+        {
+            Dispose(true);
+            GC.SuppressFinalize(this);
+        }
+
+        /// <summary>
+        /// Releases unmanaged and optionally managed resources.
+        /// </summary>
+        /// <param name="disposing"><c>true</c> to release both managed and unmanaged resources; <c>false</c> to release only unmanaged resources.</param>
+        protected virtual void Dispose(bool disposing)
+        {
+            if (_disposed)
+            {
+                return;
+            }
+
+            _sessionManager.SessionEnded -= _sessionManager_SessionEnded;
+            _sessionManager.PlaybackStopped -= _sessionManager_PlaybackStopped;
+
+            _disposed = true;
+        }
+
+        private void CheckDisposed()
+        {
+            if (_disposed)
+            {
+                throw new ObjectDisposedException(GetType().Name);
+            }
+        }
+
+        void _sessionManager_SessionEnded(object sender, SessionEventArgs e)
+        {
+            LeaveGroup(e.SessionInfo);
+        }
+
+        void _sessionManager_PlaybackStopped(object sender, PlaybackStopEventArgs e)
+        {
+            LeaveGroup(e.Session);
+        }
+
+        private bool IsUserInGroup(SessionInfo user)
+        {
+            return _userToGroupMap.ContainsKey(user.Id);
+        }
+
+        private Guid? GetUserGroup(SessionInfo user)
+        {
+            ISyncplayController group;
+            _userToGroupMap.TryGetValue(user.Id, out group);
+            if (group != null)
+            {
+                return group.GetGroupId();
+            }
+            else
+            {
+                return null;
+            }
+        }
+
+        /// <inheritdoc />
+        public void NewGroup(SessionInfo user)
+        {
+            if (IsUserInGroup(user))
+            {
+                LeaveGroup(user);
+            }
+
+            var group = new SyncplayController(_logger, _sessionManager, this);
+            _groups[group.GetGroupId().ToString()] = group;
+
+            group.InitGroup(user);
+        }
+
+        /// <inheritdoc />
+        public void JoinGroup(SessionInfo user, string groupId)
+        {
+            if (IsUserInGroup(user))
+            {
+                if (GetUserGroup(user).Equals(groupId)) return;
+                LeaveGroup(user);
+            }
+
+            ISyncplayController group;
+            _groups.TryGetValue(groupId, out group);
+
+            if (group == null)
+            {
+                _logger.LogError("Syncplaymanager JoinGroup: " + groupId + " does not exist.");
+
+                var update = new SyncplayGroupUpdate<string>();
+                update.Type = SyncplayGroupUpdateType.NotInGroup;
+                _sessionManager.SendSyncplayGroupUpdate(user.Id.ToString(), update, CancellationToken.None);
+                return;
+            }
+            group.UserJoin(user);
+        }
+
+        /// <inheritdoc />
+        public void LeaveGroup(SessionInfo user)
+        {
+            ISyncplayController group;
+            _userToGroupMap.TryGetValue(user.Id, out group);
+
+            if (group == null)
+            {
+                _logger.LogWarning("Syncplaymanager HandleRequest: " + user.Id + " not in group.");
+
+                var update = new SyncplayGroupUpdate<string>();
+                update.Type = SyncplayGroupUpdateType.NotInGroup;
+                _sessionManager.SendSyncplayGroupUpdate(user.Id.ToString(), update, CancellationToken.None);
+                return;
+            }
+            group.UserLeave(user);
+
+            if (group.IsGroupEmpty())
+            {
+                _groups.Remove(group.GetGroupId().ToString(), out _);
+            }
+        }
+
+        /// <inheritdoc />
+        public List<GroupInfoView> ListGroups(SessionInfo user)
+        {
+            // Filter by playing item if the user is viewing something already
+            if (user.NowPlayingItem != null)
+            {
+                return _groups.Values.Where(
+                    group => group.GetPlayingItemId().Equals(user.FullNowPlayingItem.Id)
+                ).Select(
+                    group => group.GetInfo()
+                ).ToList();
+            }
+            // Otherwise show all available groups
+            else
+            {
+                return _groups.Values.Select(
+                    group => group.GetInfo()
+                ).ToList();
+            }
+        }
+
+        /// <inheritdoc />
+        public void HandleRequest(SessionInfo user, SyncplayRequestInfo request)
+        {
+            ISyncplayController group;
+            _userToGroupMap.TryGetValue(user.Id, out group);
+
+            if (group == null)
+            {
+                _logger.LogWarning("Syncplaymanager HandleRequest: " + user.Id + " not in group.");
+
+                var update = new SyncplayGroupUpdate<string>();
+                update.Type = SyncplayGroupUpdateType.NotInGroup;
+                _sessionManager.SendSyncplayGroupUpdate(user.Id.ToString(), update, CancellationToken.None);
+                return;
+            }
+            group.HandleRequest(user, request);
+        }
+        
+        /// <inheritdoc />
+        public void MapUserToGroup(SessionInfo user, ISyncplayController group)
+        {
+            if (IsUserInGroup(user))
+            {
+                throw new InvalidOperationException("User in other group already!");
+            }
+            _userToGroupMap[user.Id] = group;
+        }
+
+        /// <inheritdoc />
+        public void UnmapUserFromGroup(SessionInfo user, ISyncplayController group)
+        {
+            if (!IsUserInGroup(user))
+            {
+                throw new InvalidOperationException("User not in any group!");
+            }
+
+            ISyncplayController tempGroup;
+            _userToGroupMap.Remove(user.Id, out tempGroup);
+
+            if (!tempGroup.GetGroupId().Equals(group.GetGroupId()))
+            {
+                throw new InvalidOperationException("User was in wrong group!");
+            }
+        }
+    }
+}