Example: Answering an incoming call

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voiceAIClient.sessionUpdate({
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  session: {
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    type: "realtime",
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    instructions: SYSTEM_PROMPT,
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    voice: "alloy",
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    output_modalities: ["audio"],
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    turn_detection: { type: "server_vad", interrupt_response: true },
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  },
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});

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VoxEngine.sendMediaBetween(call, voiceAIClient);

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voiceAIClient.addEventListener(OpenAI.RealtimeAPIEvents.InputAudioBufferSpeechStarted, () => {
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  voiceAIClient.clearMediaBuffer();
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});

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/**
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 * Voximplant + OpenAI Realtime API connector demo
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 * Scenario: answer an incoming call and bridge it to OpenAI Realtime.
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 */
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require(Modules.OpenAI);
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const SYSTEM_PROMPT = `
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You are Voxi, a helpful voice assistant for phone callers.
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Keep responses short and telephony-friendly (usually 1-2 sentences).
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`;
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const SESSION_CONFIG = {
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    session: {
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        type: "realtime",
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        instructions: SYSTEM_PROMPT,
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        voice: "alloy",
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        output_modalities: ["audio"],
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        turn_detection: {type: "server_vad", interrupt_response: true},
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    },
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};
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VoxEngine.addEventListener(AppEvents.CallAlerting, async ({call}) => {
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    let voiceAIClient;
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    call.addEventListener(CallEvents.Disconnected, () => VoxEngine.terminate());
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    call.addEventListener(CallEvents.Failed, () => VoxEngine.terminate());
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    try {
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        call.answer();
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        // call.record({hd_audio: true, stereo: true}); // Optional: record the call
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        voiceAIClient = await OpenAI.createRealtimeAPIClient({
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            apiKey: VoxEngine.getSecretValue('OPENAI_API_KEY'),
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            model: "gpt-realtime-1.5",
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            onWebSocketClose: (event) => {
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                Logger.write("===OpenAI.WebSocket.Close===");
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                if (event) Logger.write(JSON.stringify(event));
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                VoxEngine.terminate();
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            },
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        });
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        //---------------------- Event handlers -----------------------
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        voiceAIClient.addEventListener(OpenAI.RealtimeAPIEvents.SessionCreated, () => {
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            voiceAIClient.sessionUpdate(SESSION_CONFIG);
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        });
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        voiceAIClient.addEventListener(OpenAI.RealtimeAPIEvents.SessionUpdated, () => {
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            VoxEngine.sendMediaBetween(call, voiceAIClient);
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            voiceAIClient.responseCreate({instructions: "Hello! How can I help today?"});
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        });
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        // Barge-in: clear buffered audio when the caller starts speaking
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        voiceAIClient.addEventListener(OpenAI.RealtimeAPIEvents.InputAudioBufferSpeechStarted, () => {
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            Logger.write("===BARGE-IN: OpenAI.InputAudioBufferSpeechStarted===");
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            voiceAIClient.clearMediaBuffer();
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        });
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        voiceAIClient.addEventListener(
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            OpenAI.RealtimeAPIEvents.ConversationItemInputAudioTranscriptionCompleted,
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            (event) => {
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                const payload = event?.data?.payload || event?.data || {};
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                const transcript = payload.transcript || payload.text || payload.delta;
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                if (transcript) Logger.write(`===USER=== ${transcript}`);
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            }
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        );
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        voiceAIClient.addEventListener(
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            OpenAI.RealtimeAPIEvents.ResponseOutputAudioTranscriptDelta,
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            (event) => {
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                const payload = event?.data?.payload || event?.data || {};
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                if (payload.delta) Logger.write(`===AGENT_DELTA=== ${payload.delta}`);
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            }
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        );
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        voiceAIClient.addEventListener(
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            OpenAI.RealtimeAPIEvents.ResponseOutputAudioTranscriptDone,
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            (event) => {
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                const payload = event?.data?.payload || event?.data || {};
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                const transcript = payload.transcript || payload.text;
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                if (transcript) Logger.write(`===AGENT=== ${transcript}`);
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            }
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        );
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        // Consolidated "log-only" handlers - key OpenAI/VoxEngine debugging events
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        [
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            OpenAI.RealtimeAPIEvents.ResponseCreated,
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            OpenAI.RealtimeAPIEvents.ResponseDone,
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            OpenAI.RealtimeAPIEvents.ResponseOutputAudioDone,
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            OpenAI.RealtimeAPIEvents.ConnectorInformation,
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            OpenAI.RealtimeAPIEvents.HTTPResponse,
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            OpenAI.RealtimeAPIEvents.WebSocketError,
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            OpenAI.RealtimeAPIEvents.Unknown,
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            OpenAI.Events.WebSocketMediaStarted,
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            OpenAI.Events.WebSocketMediaEnded,
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        ].forEach((eventName) => {
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            voiceAIClient.addEventListener(eventName, (event) => {
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                Logger.write(`===${event.name}===`);
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                if (event?.data) Logger.write(JSON.stringify(event.data));
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            });
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        });
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    } catch (error) {
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        Logger.write("===UNHANDLED_ERROR===");
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        Logger.write(error);
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        voiceAIClient?.close();
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        VoxEngine.terminate();
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    }
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});