Extract agent components (#693)

Author: pblazej

Sources/LiveKit/Types/AgentState.swift renamed to Sources/LiveKit/Agent/AgentState.swift

@@ -0,0 +1,48 @@
+/*
+ * Copyright 2025 LiveKit
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import Foundation
+
+public extension Participant {
+    @objc
+    var isAgent: Bool {
+        switch kind {
+        case .agent: return true
+        default: return false
+        }
+    }
+
+    @objc
+    var agentState: AgentState {
+        guard isAgent else { return .unknown }
+        guard let attrString = attributes[agentStateAttributeKey] else { return .unknown }
+        guard let state = AgentState.fromString(attrString) else { return .unknown }
+        return state
+    }
+}
+
+public extension Participant {
+    private var publishingOnBehalf: [Participant.Identity: Participant] {
+        guard let _room else { return [:] }
+        return _room.allParticipants.filter { $0.value.attributes[publishOnBehalfAttributeKey] == identity?.stringValue }
+    }
+
+    /// The avatar worker participant associated with the agent.
+    @objc
+    var avatarWorker: Participant? {
+        publishingOnBehalf.values.first
+    }
+}

Sources/LiveKit/Agent/Participant+Agent.swift

@@ -0,0 +1,36 @@
+/*
+ * Copyright 2025 LiveKit
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import Foundation
+
+let publishOnBehalfAttributeKey = "lk.publish_on_behalf"
+
+public extension Room {
+    /// A dictionary containing all agent participants.
+    ///
+    /// - Note: This will not include participants that are publishing on behalf of another participant
+    /// e.g. avatar workers. To access them directly use ``Participant/avatarWorker`` property of `agentParticipant`.
+    @objc
+    var agentParticipants: [Participant.Identity: Participant] {
+        allParticipants.filter { $0.value.isAgent && $0.value.attributes[publishOnBehalfAttributeKey] == nil }
+    }
+
+    /// The first agent participant.
+    @objc
+    var agentParticipant: Participant? {
+        agentParticipants.values.first
+    }
+}

Sources/LiveKit/Agent/Room+Agent.swift

@@ -134,7 +134,7 @@ public extension Sequence where Iterator.Element == AudioLevel {
     }
 }
 
-public class AudioVisualizeProcessor {
+public actor AudioVisualizeProcessor {
     static let bufferSize = 1024
 
     // MARK: - Public

Sources/LiveKit/Convenience/AudioProcessing.swift

@@ -75,14 +75,6 @@ public class Participant: NSObject, @unchecked Sendable, ObservableObject, Logga
         _state.trackPublications.values.filter { $0.kind == .video }
     }
 
-    @objc
-    public var agentState: AgentState {
-        guard case .agent = kind else { return .unknown }
-        guard let attrString = _state.attributes[agentStateAttributeKey] else { return .connecting }
-        guard let state = AgentState.fromString(attrString) else { return .connecting }
-        return state
-    }
-
     var info: Livekit_ParticipantInfo?
 
     // Reference to the Room this Participant belongs to