feat(voice): support per-client conversation mode state

packages/server/src/plugins/voice-mode.ts

@@ -0,0 +1,96 @@
+import type { Logger } from "../logger"
+import type { ClientConnectionManager, ClientConnectionRef } from "../clients/connection-manager"
+import type { PluginChannelManager } from "./channel"
+
+interface VoiceModeManagerOptions {
+  connections: ClientConnectionManager
+  channel: PluginChannelManager
+  logger: Logger
+}
+
+export class VoiceModeManager {
+  private readonly enabledConnectionsByInstance = new Map<string, Set<string>>()
+  private readonly aggregateByInstance = new Map<string, boolean>()
+
+  constructor(private readonly options: VoiceModeManagerOptions) {
+    this.options.connections.subscribe((event) => {
+      if (event.type !== "disconnected") return
+      this.clearConnection(event.connection)
+    })
+  }
+
+  setEnabled(instanceId: string, connection: ClientConnectionRef, enabled: boolean): void {
+    if (enabled && !this.options.connections.isConnected(connection)) {
+      this.options.logger.debug(
+        { instanceId, clientId: connection.clientId, connectionId: connection.connectionId },
+        "Ignoring voice mode enable for disconnected client connection",
+      )
+      return
+    }
+
+    const key = getConnectionKey(connection)
+    const current = this.enabledConnectionsByInstance.get(instanceId) ?? new Set<string>()
+
+    if (enabled) {
+      current.add(key)
+      this.enabledConnectionsByInstance.set(instanceId, current)
+    } else if (current.delete(key)) {
+      if (current.size === 0) {
+        this.enabledConnectionsByInstance.delete(instanceId)
+      } else {
+        this.enabledConnectionsByInstance.set(instanceId, current)
+      }
+    }
+
+    this.options.logger.debug({ instanceId, clientId: connection.clientId, connectionId: connection.connectionId, enabled }, "Voice mode updated for client connection")
+    this.publishIfChanged(instanceId)
+  }
+
+  syncInstance(instanceId: string): void {
+    this.options.channel.send(instanceId, buildVoiceModeEvent(this.isEnabled(instanceId)))
+  }
+
+  isEnabled(instanceId: string): boolean {
+    return this.aggregateByInstance.get(instanceId) === true
+  }
+
+  private clearConnection(connection: ClientConnectionRef): void {
+    const key = getConnectionKey(connection)
+    for (const [instanceId, enabledConnections] of Array.from(this.enabledConnectionsByInstance.entries())) {
+      if (!enabledConnections.delete(key)) continue
+      if (enabledConnections.size === 0) {
+        this.enabledConnectionsByInstance.delete(instanceId)
+      }
+      this.publishIfChanged(instanceId)
+    }
+  }
+
+  private publishIfChanged(instanceId: string): void {
+    const enabled = (this.enabledConnectionsByInstance.get(instanceId)?.size ?? 0) > 0
+    const previous = this.aggregateByInstance.get(instanceId) === true
+    if (enabled === previous) return
+
+    if (enabled) {
+      this.aggregateByInstance.set(instanceId, true)
+    } else {
+      this.aggregateByInstance.delete(instanceId)
+    }
+
+    this.options.logger.debug({ instanceId, enabled }, "Broadcasting aggregate voice mode")
+    this.options.channel.send(instanceId, buildVoiceModeEvent(enabled))
+  }
+}
+
+function buildVoiceModeEvent(enabled: boolean) {
+  return {
+    type: "codenomad.voiceMode",
+    properties: {
+      enabled,
+      formatVersion: "v1",
+    },
+  }
+}
+
+function getConnectionKey(connection: ClientConnectionRef): string {
+  return `${connection.clientId}:${connection.connectionId}`
+}