Surveillance camera listening/speaking (#11640)

Content.Server/SurveillanceCamera/Systems/SurveillanceCameraMicrophoneSystem.cs

@@ -0,0 +1,48 @@
+using Content.Shared.IdentityManagement;
+using Content.Shared.Interaction;
+
+namespace Content.Server.SurveillanceCamera;
+
+public sealed class SurveillanceCameraMicrophoneSystem : EntitySystem
+{
+    [Dependency] private SharedInteractionSystem _interactionSystem = default!;
+
+    public bool CanListen(EntityUid source, EntityUid speaker, SurveillanceCameraMicrophoneComponent? microphone = null)
+    {
+        if (!Resolve(source, ref microphone))
+        {
+            return false;
+        }
+
+        return microphone.Enabled
+               && !microphone.BlacklistedComponents.IsValid(speaker)
+               && _interactionSystem.InRangeUnobstructed(source, speaker, range: microphone.ListenRange);
+    }
+    public void RelayEntityMessage(EntityUid source, EntityUid speaker, string message, SurveillanceCameraComponent? camera = null)
+    {
+        if (!Resolve(source, ref camera))
+        {
+            return;
+        }
+
+        var ev = new SurveillanceCameraSpeechSendEvent(speaker, message);
+
+        foreach (var monitor in camera.ActiveMonitors)
+        {
+            RaiseLocalEvent(monitor, ev);
+        }
+    }
+}
+
+public sealed class SurveillanceCameraSpeechSendEvent : EntityEventArgs
+{
+    public EntityUid Speaker { get; }
+    public string Message { get; }
+
+    public SurveillanceCameraSpeechSendEvent(EntityUid speaker, string message)
+    {
+        Speaker = speaker;
+        Message = message;
+    }
+}
+