1 files changed, 169 insertions, 0 deletions
diff --git a/MediaBrowser.Controller/SyncPlay/GroupInfo.cs b/MediaBrowser.Controller/SyncPlay/GroupInfo.cs
new file mode 100644
index 000000000..28a3ac505
--- /dev/null
+++ b/MediaBrowser.Controller/SyncPlay/GroupInfo.cs
@@ -0,0 +1,169 @@
+using System;
+using System.Collections.Generic;
+using MediaBrowser.Controller.Entities;
+using MediaBrowser.Controller.Session;
+
+namespace MediaBrowser.Controller.SyncPlay
+{
+    /// <summary>
+    /// Class GroupInfo.
+    /// </summary>
+    /// <remarks>
+    /// Class is not thread-safe, external locking is required when accessing methods.
+    /// </remarks>
+    public class GroupInfo
+    {
+        /// <summary>
+        /// Default ping value used for sessions.
+        /// </summary>
+        public long DefaulPing { get; } = 500;
+
+        /// <summary>
+        /// Gets or sets the group identifier.
+        /// </summary>
+        /// <value>The group identifier.</value>
+        public Guid GroupId { get; } = Guid.NewGuid();
+
+        /// <summary>
+        /// Gets or sets the playing item.
+        /// </summary>
+        /// <value>The playing item.</value>
+        public BaseItem PlayingItem { get; set; }
+
+        /// <summary>
+        /// Gets or sets whether playback is paused.
+        /// </summary>
+        /// <value>Playback is paused.</value>
+        public bool IsPaused { get; set; }
+
+        /// <summary>
+        /// Gets or sets the position ticks.
+        /// </summary>
+        /// <value>The position ticks.</value>
+        public long PositionTicks { get; set; }
+
+        /// <summary>
+        /// Gets or sets the last activity.
+        /// </summary>
+        /// <value>The last activity.</value>
+        public DateTime LastActivity { get; set; }
+
+        /// <summary>
+        /// Gets the participants.
+        /// </summary>
+        /// <value>The participants, or members of the group.</value>
+        public Dictionary<string, GroupMember> Participants { get; } =
+            new Dictionary<string, GroupMember>(StringComparer.OrdinalIgnoreCase);
+
+        /// <summary>
+        /// Checks if a session is in this group.
+        /// </summary>
+        /// <value><c>true</c> if the session is in this group; <c>false</c> otherwise.</value>
+        public bool ContainsSession(string sessionId)
+        {
+            return Participants.ContainsKey(sessionId);
+        }
+
+        /// <summary>
+        /// Adds the session to the group.
+        /// </summary>
+        /// <param name="session">The session.</param>
+        public void AddSession(SessionInfo session)
+        {
+            if (ContainsSession(session.Id.ToString()))
+            {
+                return;
+            }
+
+            var member = new GroupMember();
+            member.Session = session;
+            member.Ping = DefaulPing;
+            member.IsBuffering = false;
+            Participants[session.Id.ToString()] = member;
+        }
+
+        /// <summary>
+        /// Removes the session from the group.
+        /// </summary>
+        /// <param name="session">The session.</param>
+        public void RemoveSession(SessionInfo session)
+        {
+            if (!ContainsSession(session.Id.ToString()))
+            {
+                return;
+            }
+
+            Participants.Remove(session.Id.ToString(), out _);
+        }
+
+        /// <summary>
+        /// Updates the ping of a session.
+        /// </summary>
+        /// <param name="session">The session.</param>
+        /// <param name="ping">The ping.</param>
+        public void UpdatePing(SessionInfo session, long ping)
+        {
+            if (!ContainsSession(session.Id.ToString()))
+            {
+                return;
+            }
+
+            Participants[session.Id.ToString()].Ping = ping;
+        }
+
+        /// <summary>
+        /// Gets the highest ping in the group.
+        /// </summary>
+        /// <value name="session">The highest ping in the group.</value>
+        public long GetHighestPing()
+        {
+            long max = Int64.MinValue;
+            foreach (var session in Participants.Values)
+            {
+                max = Math.Max(max, session.Ping);
+            }
+            return max;
+        }
+
+        /// <summary>
+        /// Sets the session's buffering state.
+        /// </summary>
+        /// <param name="session">The session.</param>
+        /// <param name="isBuffering">The state.</param>
+        public void SetBuffering(SessionInfo session, bool isBuffering)
+        {
+            if (!ContainsSession(session.Id.ToString()))
+            {
+                return;
+            }
+
+            Participants[session.Id.ToString()].IsBuffering = isBuffering;
+        }
+
+        /// <summary>
+        /// Gets the group buffering state.
+        /// </summary>
+        /// <value><c>true</c> if there is a session buffering in the group; <c>false</c> otherwise.</value>
+        public bool IsBuffering()
+        {
+            foreach (var session in Participants.Values)
+            {
+                if (session.IsBuffering)
+                {
+                    return true;
+                }
+            }
+
+            return false;
+        }
+
+        /// <summary>
+        /// Checks if the group is empty.
+        /// </summary>
+        /// <value><c>true</c> if the group is empty; <c>false</c> otherwise.</value>
+        public bool IsEmpty()
+        {
+            return Participants.Count == 0;
+        }
+    }
+}