Example: Answering an incoming call

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VoxEngine.sendMediaBetween(call, geminiLiveAPIClient);

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geminiLiveAPIClient.sendRealtimeInput({
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  text: GREETING_TRIGGER,
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});

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if (payload.interrupted) {
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  geminiLiveAPIClient.clearMediaBuffer();
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}

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geminiLiveAPIClient.addEventListener(Gemini.LiveAPIEvents.ServerContent, (event) => {
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  const payload = event?.data?.payload || {};
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  if (payload.inputTranscription?.text) Logger.write(payload.inputTranscription.text);
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  if (payload.outputTranscription?.text) Logger.write(payload.outputTranscription.text);
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});

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/**
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 * Voximplant + Gemini Live API connector demo
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 * Scenario: answer an incoming call and bridge it to Gemini Live API.
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 */
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require(Modules.Gemini);
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require(Modules.ApplicationStorage);
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const SYSTEM_PROMPT = `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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// -------------------- Gemini Live API settings --------------------
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const CONNECT_CONFIG = {
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    responseModalities: ["AUDIO"],
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    thinkingConfig: {thinkingLevel: "minimal"},
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    speechConfig: {
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        voiceConfig: {
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            prebuiltVoiceConfig: {voiceName: "Aoede"},
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        },
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    },
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    systemInstruction: {
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        parts: [{text: SYSTEM_PROMPT}],
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    },
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    inputAudioTranscription: {},
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    outputAudioTranscription: {},
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};
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VoxEngine.addEventListener(AppEvents.CallAlerting, async ({call}) => {
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    let voiceAIClient;
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    // Termination functions - add cleanup and logging as needed
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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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        // Create client and connect to Gemini Live API
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        voiceAIClient = await Gemini.createLiveAPIClient({
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            apiKey: (await ApplicationStorage.get("GEMINI_API_KEY")).value,
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            model: "gemini-3.1-flash-live-preview",
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            backend: Gemini.Backend.GEMINI_API,
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            connectConfig: CONNECT_CONFIG,
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            onWebSocketClose: (event) => {
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                Logger.write("===Gemini.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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        // Wait for Gemini setup, then bridge audio and trigger the greeting
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        voiceAIClient.addEventListener(Gemini.LiveAPIEvents.SetupComplete, () => {
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            VoxEngine.sendMediaBetween(call, voiceAIClient);
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            voiceAIClient.sendRealtimeInput({
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                text: "Say hello and ask how you can help.",
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            });
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        });
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        // Capture transcripts + handle barge-in
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        voiceAIClient.addEventListener(Gemini.LiveAPIEvents.ServerContent, (event) => {
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            const payload = event?.data?.payload || {};
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            if (payload.inputTranscription?.text) {
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                Logger.write(`===USER=== ${payload.inputTranscription.text}`);
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            }
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            if (payload.outputTranscription?.text) {
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                Logger.write(`===AGENT=== ${payload.outputTranscription.text}`);
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            }
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            if (payload.interrupted) {
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                Logger.write("===BARGE-IN=== Gemini.LiveAPIEvents.ServerContent");
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                voiceAIClient.clearMediaBuffer();
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            }
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        });
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        // Log all Gemini events for illustration/debugging
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        [
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            Gemini.LiveAPIEvents.SetupComplete,
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            Gemini.LiveAPIEvents.ServerContent,
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            Gemini.LiveAPIEvents.ToolCall,
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            Gemini.LiveAPIEvents.ToolCallCancellation,
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            Gemini.LiveAPIEvents.ConnectorInformation,
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            Gemini.LiveAPIEvents.Unknown,
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            Gemini.Events.WebSocketMediaStarted,
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            Gemini.Events.WebSocketMediaEnded,
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        ].forEach((eventName) => {
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            voiceAIClient.addEventListener(eventName, (event) => {
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                Logger.write(`===${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("===SOMETHING_WENT_WRONG===");
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        Logger.write(error);
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        voiceAIClient?.close();
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        VoxEngine.terminate();    }
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});