feat: Add initial implementation of CI/CD workflows, documentation, and testing framework

src/EchoHub.Tests/PresenceTrackerTests.cs

@@ -0,0 +1,68 @@
+using EchoHub.Server.Services;
+using Xunit;
+
+namespace EchoHub.Tests;
+
+public class PresenceTrackerTests
+{
+    [Fact]
+    public void UserConnected_IsOnline_ReturnsTrue()
+    {
+        var tracker = new PresenceTracker();
+        tracker.UserConnected("conn1", Guid.NewGuid(), "alice");
+        Assert.True(tracker.IsOnline("alice"));
+    }
+
+    [Fact]
+    public void UserDisconnected_LastConnection_IsOnlineReturnsFalse()
+    {
+        var tracker = new PresenceTracker();
+        tracker.UserConnected("conn1", Guid.NewGuid(), "alice");
+        tracker.UserDisconnected("conn1");
+        Assert.False(tracker.IsOnline("alice"));
+    }
+
+    [Fact]
+    public void MultipleConnections_DisconnectOne_StillOnline()
+    {
+        var tracker = new PresenceTracker();
+        var userId = Guid.NewGuid();
+        tracker.UserConnected("conn1", userId, "alice");
+        tracker.UserConnected("conn2", userId, "alice");
+        tracker.UserDisconnected("conn1");
+        Assert.True(tracker.IsOnline("alice"));
+    }
+
+    [Fact]
+    public void JoinChannel_GetOnlineUsersInChannel_ReturnsUser()
+    {
+        var tracker = new PresenceTracker();
+        tracker.UserConnected("conn1", Guid.NewGuid(), "alice");
+        tracker.JoinChannel("alice", "general");
+        var users = tracker.GetOnlineUsersInChannel("general");
+        Assert.Contains("alice", users);
+    }
+
+    [Fact]
+    public void LeaveChannel_UserNoLongerInChannel()
+    {
+        var tracker = new PresenceTracker();
+        tracker.UserConnected("conn1", Guid.NewGuid(), "alice");
+        tracker.JoinChannel("alice", "general");
+        tracker.LeaveChannel("alice", "general");
+        var users = tracker.GetOnlineUsersInChannel("general");
+        Assert.DoesNotContain("alice", users);
+    }
+
+    [Fact]
+    public void GetChannelsForUser_ReturnsJoinedChannels()
+    {
+        var tracker = new PresenceTracker();
+        tracker.UserConnected("conn1", Guid.NewGuid(), "alice");
+        tracker.JoinChannel("alice", "general");
+        tracker.JoinChannel("alice", "random");
+        var channels = tracker.GetChannelsForUser("alice");
+        Assert.Contains("general", channels);
+        Assert.Contains("random", channels);
+    }
+}