feat: Add character names to scenarios and UI

Introduces `characterName` to the `Scenario` type, enabling AI personas to be explicitly named. This change also updates the `ScenarioCard` component to display the character name and adds foundational support for potential future scenario deletion functionality. The README has been updated with a new AI Studio link.

App.tsx

@@ -1,5 +1,5 @@
 
-import React, { useState, useEffect } from 'react';
+import React, { useState, useEffect, useCallback } from 'react';
 import { SCENARIOS } from './constants';
 import { Scenario, SessionMode, UserSettings } from './types';
 import ScenarioCard from './components/ScenarioCard';
@@ -17,26 +17,44 @@ const DEFAULT_SETTINGS: UserSettings = {
   genderPreference: 'Neutral'
 };
 
+const CUSTOM_SCENARIOS_KEY = 'cognitive-clarity-custom-scenarios';
+const SETTINGS_KEY = 'cognitive-clarity-settings';
+
 const App: React.FC = () => {
   const [activeScenario, setActiveScenario] = useState<Scenario | null>(null);
   const [sessionMode, setSessionMode] = useState<SessionMode>('text');
   const [selectedDifficulty, setSelectedDifficulty] = useState<string>('All');
   const [isPreparing, setIsPreparing] = useState(false);
   
-  // Custom Scenarios State
-  const [customScenarios, setCustomScenarios] = useState<Scenario[]>([]);
+  // Custom Scenarios State with LocalStorage persistence
+  const [customScenarios, setCustomScenarios] = useState<Scenario[]>(() => {
+    try {
+      const saved = localStorage.getItem(CUSTOM_SCENARIOS_KEY);
+      return saved ? JSON.parse(saved) : [];
+    } catch (e) {
+      console.error("Failed to load custom scenarios", e);
+      return [];
+    }
+  });
+
   const [showGenerator, setShowGenerator] = useState(false);
   const [showReference, setShowReference] = useState(false);
   const [showSettings, setShowSettings] = useState(false);
 
   // User Settings State
   const [userSettings, setUserSettings] = useState<UserSettings>(() => {
-    const saved = localStorage.getItem('cognitive-clarity-settings');
+    const saved = localStorage.getItem(SETTINGS_KEY);
     return saved ? JSON.parse(saved) : DEFAULT_SETTINGS;
   });
 
+  // Save scenarios whenever they change
   useEffect(() => {
-    localStorage.setItem('cognitive-clarity-settings', JSON.stringify(userSettings));
+    localStorage.setItem(CUSTOM_SCENARIOS_KEY, JSON.stringify(customScenarios));
+  }, [customScenarios]);
+
+  // Save settings whenever they change
+  useEffect(() => {
+    localStorage.setItem(SETTINGS_KEY, JSON.stringify(userSettings));
   }, [userSettings]);
 
   const handleSelectScenario = (scenario: Scenario, mode: SessionMode) => {
@@ -57,6 +75,10 @@ const App: React.FC = () => {
     setShowGenerator(false);
   };
 
+  const handleDeleteScenario = useCallback((id: string) => {
+    setCustomScenarios(prev => prev.filter(s => s.id !== id));
+  }, []);
+
   const allScenarios = [...customScenarios, ...SCENARIOS];
   const filteredScenarios = allScenarios.filter(scenario => 
     selectedDifficulty === 'All' || scenario.difficulty === selectedDifficulty
@@ -125,6 +147,7 @@ const App: React.FC = () => {
                scenario={activeScenario} 
                onExit={handleExitSession} 
                voiceSettings={userSettings} 
+               onUpdateSettings={setUserSettings}
              />
           </div>
         )}
@@ -233,7 +256,12 @@ const App: React.FC = () => {
 
         <div className="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-3 gap-6">
           {filteredScenarios.map(scenario => (
-            <ScenarioCard key={scenario.id} scenario={scenario} onSelect={handleSelectScenario} />
+            <ScenarioCard 
+              key={scenario.id} 
+              scenario={scenario} 
+              onSelect={handleSelectScenario} 
+              onDelete={scenario.id.startsWith('custom-') ? handleDeleteScenario : undefined}
+            />
           ))}
           <button 
             onClick={() => setShowGenerator(true)}

README.md

@@ -6,7 +6,7 @@
 
 This contains everything you need to run your app locally.
 
-View your app in AI Studio: https://ai.studio/apps/drive/1MTS72LTsm0ZY5GzQzl-a8Rpt72k1csd9
+View your app in AI Studio: https://ai.studio/apps/56e6d01a-b890-4a16-b7c2-fc7b3e52f59a
 
 ## Run Locally
 

components/AudioDeviceSelector.tsx

@@ -0,0 +1,91 @@
+
+import React, { useEffect, useState } from 'react';
+import { Mic, Check, AlertCircle } from 'lucide-react';
+
+interface AudioDeviceSelectorProps {
+  selectedDeviceId?: string;
+  onSelect: (deviceId: string) => void;
+  className?: string;
+}
+
+const AudioDeviceSelector: React.FC<AudioDeviceSelectorProps> = ({ 
+  selectedDeviceId, 
+  onSelect,
+  className = ""
+}) => {
+  const [devices, setDevices] = useState<MediaDeviceInfo[]>([]);
+  const [error, setError] = useState<string | null>(null);
+
+  const getDevices = async () => {
+    try {
+      // Request permission first to get labels
+      await navigator.mediaDevices.getUserMedia({ audio: true });
+      const allDevices = await navigator.mediaDevices.enumerateDevices();
+      const audioInputs = allDevices.filter(device => device.kind === 'audioinput');
+      setDevices(audioInputs);
+      
+      // If no device is selected but we have devices, select the first one
+      if (!selectedDeviceId && audioInputs.length > 0) {
+        onSelect(audioInputs[0].deviceId);
+      }
+    } catch (err) {
+      console.error("Error accessing audio devices:", err);
+      setError("Microphone access denied. Please check your browser permissions.");
+    }
+  };
+
+  useEffect(() => {
+    getDevices();
+    
+    // Listen for device changes (e.g., plugging in a new mic)
+    navigator.mediaDevices.addEventListener('devicechange', getDevices);
+    return () => {
+      navigator.mediaDevices.removeEventListener('devicechange', getDevices);
+    };
+  }, []);
+
+  if (error) {
+    return (
+      <div className="flex items-center gap-2 p-3 bg-red-50 border border-red-100 rounded-xl text-red-600 text-xs">
+        <AlertCircle size={14} />
+        <span>{error}</span>
+      </div>
+    );
+  }
+
+  return (
+    <div className={`space-y-2 ${className}`}>
+      <label className="text-[10px] font-black text-slate-400 uppercase tracking-widest flex items-center gap-2 mb-1">
+        <Mic size={12} />
+        Input Device
+      </label>
+      <div className="grid grid-cols-1 gap-2">
+        {devices.length === 0 ? (
+          <p className="text-xs text-slate-400 italic p-2">Searching for devices...</p>
+        ) : (
+          devices.map((device) => (
+            <button
+              key={device.deviceId}
+              onClick={() => onSelect(device.deviceId)}
+              className={`flex items-center justify-between p-3 rounded-xl border transition-all text-left text-xs ${
+                selectedDeviceId === device.deviceId || (device.deviceId === 'default' && !selectedDeviceId)
+                  ? 'bg-teal-50 border-teal-500 text-teal-900'
+                  : 'bg-white border-slate-100 hover:border-slate-200 text-slate-600'
+              }`}
+            >
+              <div className="flex items-center gap-3 truncate">
+                <Mic size={14} className={selectedDeviceId === device.deviceId ? 'text-teal-600' : 'text-slate-400'} />
+                <span className="truncate font-medium">{device.label || `Microphone ${device.deviceId.slice(0, 5)}...`}</span>
+              </div>
+              {(selectedDeviceId === device.deviceId || (device.deviceId === 'default' && !selectedDeviceId)) && (
+                <Check size={14} className="text-teal-600 flex-shrink-0" />
+              )}
+            </button>
+          ))
+        )}
+      </div>
+    </div>
+  );
+};
+
+export default AudioDeviceSelector;

components/ScenarioCard.tsx

@@ -1,15 +1,16 @@
 
 import React from 'react';
 import { Scenario } from '../types';
-import { Mic, MessageSquare, Info } from 'lucide-react';
+import { Mic, MessageSquare, Trash2 } from 'lucide-react';
 import Tooltip from './Tooltip';
 
 interface ScenarioCardProps {
   scenario: Scenario;
   onSelect: (scenario: Scenario, mode: 'text' | 'voice') => void;
+  onDelete?: (id: string) => void;
 }
 
-const ScenarioCard: React.FC<ScenarioCardProps> = ({ scenario, onSelect }) => {
+const ScenarioCard: React.FC<ScenarioCardProps> = ({ scenario, onSelect, onDelete }) => {
   const getDifficultyColor = (diff: string) => {
     switch (diff) {
       case 'Beginner': return 'bg-teal-50 text-teal-800 border-teal-100';
@@ -26,19 +27,34 @@ const ScenarioCard: React.FC<ScenarioCardProps> = ({ scenario, onSelect }) => {
   };
 
   return (
-    <div className="bg-white rounded-xl p-6 shadow-sm border border-slate-200 hover:border-teal-200 hover:shadow-md transition-all flex flex-col h-full group">
+    <div className="bg-white rounded-xl p-6 shadow-sm border border-slate-200 hover:border-teal-200 hover:shadow-md transition-all flex flex-col h-full group relative">
+      {onDelete && (
+        <button 
+          onClick={(e) => {
+            e.stopPropagation();
+            onDelete(scenario.id);
+          }}
+          className="absolute top-4 right-4 p-2 text-slate-300 hover:text-rose-500 hover:bg-rose-50 rounded-lg transition-all opacity-0 group-hover:opacity-100"
+          title="Delete custom scenario"
+        >
+          <Trash2 size={16} />
+        </button>
+      )}
+
       <div className="flex justify-between items-start mb-4">
         <Tooltip content={difficultyExplanations[scenario.difficulty]}>
           <span className={`px-2.5 py-0.5 rounded-full text-[10px] font-bold uppercase tracking-wider border cursor-help ${getDifficultyColor(scenario.difficulty)}`}>
             {scenario.difficulty}
           </span>
         </Tooltip>
+        {!onDelete && (
           <span className="text-[10px] font-bold text-slate-400 uppercase tracking-widest">
             {scenario.category}
           </span>
+        )}
       </div>
       
-      <h3 className="text-lg font-bold text-slate-800 mb-2 group-hover:text-teal-700 transition-colors">{scenario.title}</h3>
+      <h3 className="text-lg font-bold text-slate-800 mb-2 group-hover:text-teal-700 transition-colors pr-6">{scenario.title}</h3>
       <p className="text-slate-600 text-sm mb-5 flex-grow leading-relaxed font-light">{scenario.description}</p>
       
       <div className="mb-6">

components/ScenarioGenerator.tsx

@@ -1,8 +1,9 @@
+
 import React, { useState } from 'react';
 import { GoogleGenAI, Type } from "@google/genai";
 import { Scenario } from '../types';
 import { CBT_GLOSSARY } from '../constants';
-import { Sparkles, X, Loader2, AlertCircle, Info, Target, UserCircle2, BrainCircuit, Check } from 'lucide-react';
+import { Sparkles, X, Loader2, AlertCircle, Info, Target, UserCircle2, BrainCircuit, Check, BarChart } from 'lucide-react';
 
 interface ScenarioGeneratorProps {
   onGenerate: (scenario: Scenario) => void;
@@ -12,6 +13,7 @@ interface ScenarioGeneratorProps {
 const ScenarioGenerator: React.FC<ScenarioGeneratorProps> = ({ onGenerate, onCancel }) => {
   const [prompt, setPrompt] = useState('');
   const [selectedConcepts, setSelectedConcepts] = useState<string[]>([]);
+  const [selectedDifficulty, setSelectedDifficulty] = useState<Scenario['difficulty']>('Intermediate');
   const [isLoading, setIsLoading] = useState(false);
   const [error, setError] = useState<string | null>(null);
 
@@ -35,6 +37,7 @@ const ScenarioGenerator: React.FC<ScenarioGeneratorProps> = ({ onGenerate, onCan
         properties: {
           id: { type: Type.STRING },
           title: { type: Type.STRING },
+          characterName: { type: Type.STRING },
           description: { type: Type.STRING },
           category: { 
             type: Type.STRING, 
@@ -51,7 +54,7 @@ const ScenarioGenerator: React.FC<ScenarioGeneratorProps> = ({ onGenerate, onCan
             items: { type: Type.STRING } 
           }
         },
-        required: ['id', 'title', 'description', 'category', 'difficulty', 'systemInstruction', 'initialMessage', 'cbtFocus']
+        required: ['id', 'title', 'characterName', 'description', 'category', 'difficulty', 'systemInstruction', 'initialMessage', 'cbtFocus']
       };
 
       const selectedContext = selectedConcepts.length > 0 
@@ -69,17 +72,18 @@ const ScenarioGenerator: React.FC<ScenarioGeneratorProps> = ({ onGenerate, onCan
             
             CORE INSTRUCTIONS:
             1. CLINICAL FOCUS: ${selectedContext}
-            2. CATEGORIZATION: You MUST assign the scenario to exactly one of the following categories based on its primary context:
+            2. CATEGORIZATION: Based on the user's input, you MUST suggest the most appropriate category for the scenario:
                - 'Social Anxiety': Situations involving social performance, fear of judgment, or networking.
                - 'Workplace': Scenarios involving colleagues, supervisors, career growth, or professional conflict.
                - 'Relationships': Dynamics with family, friends, or romantic partners; boundary setting.
                - 'Self-Talk': Purely internal cognitive restructuring, rumination, or self-compassion work.
-            3. DIFFICULTY CALIBRATION: Assign a level based on cognitive load:
-               - 'Beginner': Low stakes, high support, clear-cut distortions.
-               - 'Intermediate': Ambiguous stakes, moderate social friction, subtle distortions.
-               - 'Advanced': High emotional triggers, persistent clinical resistance from AI character, deep-seated patterns.
-            4. INTERNAL LOGIC: The 'systemInstruction' must include a detailed "INTERNAL CBT LOGIC" section. This tells the AI how to react to the user's progress or cognitive lapses.
-            5. CONSISTENCY: Ensure 'cbtFocus' includes the selected concepts.
+            3. DIFFICULTY CALIBRATION: The user has explicitly requested a '${selectedDifficulty}' level. 
+               Generate the scenario content and the AI character's behavior to match this complexity:
+               - 'Beginner': Low stakes, high support, clear-cut distortions, AI character is cooperative.
+               - 'Intermediate': Ambiguous stakes, moderate social friction, subtle distortions, AI character has specific needs/points.
+               - 'Advanced': High emotional triggers, persistent clinical resistance from AI character, complex deep-seated cognitive patterns.
+            4. INTERNAL LOGIC: The 'systemInstruction' for the character MUST include a detailed "INTERNAL CBT LOGIC" section. This instructs the AI character how to react to the user's progress or cognitive lapses.
+            5. CHARACTER VOICE: Define a realistic voice profile for the character, including their likely emotional state (frustrated, busy, anxious, etc.).
           `
         },
         contents: [
@@ -89,6 +93,8 @@ const ScenarioGenerator: React.FC<ScenarioGeneratorProps> = ({ onGenerate, onCan
 
       if (result.text) {
         const scenario = JSON.parse(result.text) as Scenario;
+        // Enforce the user-selected difficulty in the final object
+        scenario.difficulty = selectedDifficulty;
         scenario.id = `custom-${Date.now()}-${scenario.id}`;
         onGenerate(scenario);
       } else {
@@ -162,6 +168,29 @@ const ScenarioGenerator: React.FC<ScenarioGeneratorProps> = ({ onGenerate, onCan
             </div>
           </div>
 
+          {/* Difficulty Selection */}
+          <div className="space-y-3">
+            <label className="block text-[10px] font-black text-slate-400 uppercase tracking-widest">
+              Communication Difficulty
+            </label>
+            <div className="grid grid-cols-3 gap-2">
+              {(['Beginner', 'Intermediate', 'Advanced'] as const).map((level) => (
+                <button
+                  key={level}
+                  onClick={() => setSelectedDifficulty(level)}
+                  className={`flex items-center justify-center gap-2 py-2.5 rounded-xl border-2 transition-all text-[11px] font-bold ${
+                    selectedDifficulty === level
+                      ? 'bg-teal-50 border-teal-600 text-teal-700 shadow-sm shadow-teal-50'
+                      : 'bg-white border-slate-100 text-slate-400 hover:border-slate-200'
+                  }`}
+                >
+                  <BarChart size={14} className={selectedDifficulty === level ? 'text-teal-600' : 'text-slate-300'} />
+                  {level}
+                </button>
+              ))}
+            </div>
+          </div>
+
           {/* Clinical Targets (Selection) */}
           <div className="space-y-3">
             <label className="block text-[10px] font-black text-slate-400 uppercase tracking-widest">

components/SettingsModal.tsx

@@ -1,8 +1,9 @@
 
 import React from 'react';
 import { UserSettings } from '../types';
-import { X, Volume2, Check, Info, Mic2 } from 'lucide-react';
+import { X, Volume2, Check, Info, Mic2, Settings2 } from 'lucide-react';
 import Tooltip from './Tooltip';
+import AudioDeviceSelector from './AudioDeviceSelector';
 
 interface SettingsModalProps {
   settings: UserSettings;
@@ -29,8 +30,8 @@ const VOICE_OPTIONS: VoiceOption[] = [
 const SettingsModal: React.FC<SettingsModalProps> = ({ settings, onUpdate, onClose }) => {
   return (
     <div className="fixed inset-0 z-[100] flex items-center justify-center p-4 bg-slate-900/60 backdrop-blur-md">
-      <div className="bg-white rounded-3xl shadow-2xl w-full max-w-xl overflow-hidden animate-in fade-in zoom-in duration-300 border border-slate-100">
-        <div className="p-6 bg-slate-50 border-b border-slate-200 flex justify-between items-center">
+      <div className="bg-white rounded-3xl shadow-2xl w-full max-w-xl overflow-hidden animate-in fade-in zoom-in duration-300 border border-slate-100 max-h-[90vh] flex flex-col">
+        <div className="p-6 bg-slate-50 border-b border-slate-200 flex justify-between items-center flex-shrink-0">
           <div className="flex items-center gap-3">
             <div className="bg-slate-800 p-2 rounded-xl text-white">
               <Volume2 size={20} />
@@ -45,7 +46,7 @@ const SettingsModal: React.FC<SettingsModalProps> = ({ settings, onUpdate, onClo
           </button>
         </div>
 
-        <div className="p-8 space-y-8">
+        <div className="p-8 space-y-8 overflow-y-auto">
           <section className="space-y-4">
             <div className="flex items-center justify-between">
               <h3 className="text-xs font-black text-slate-400 uppercase tracking-widest flex items-center gap-2">
@@ -94,6 +95,20 @@ const SettingsModal: React.FC<SettingsModalProps> = ({ settings, onUpdate, onClo
             </div>
           </section>
 
+          <section className="space-y-4">
+            <div className="flex items-center justify-between">
+              <h3 className="text-xs font-black text-slate-400 uppercase tracking-widest flex items-center gap-2">
+                <Settings2 size={14} className="text-teal-600" />
+                Hardware Configuration
+              </h3>
+            </div>
+            
+            <AudioDeviceSelector 
+              selectedDeviceId={settings.preferredAudioDeviceId}
+              onSelect={(deviceId) => onUpdate({ ...settings, preferredAudioDeviceId: deviceId })}
+            />
+          </section>
+
           <div className="bg-amber-50 border border-amber-100 rounded-2xl p-4 flex gap-3">
             <div className="text-amber-600 mt-0.5">
               <Info size={18} />
@@ -104,7 +119,7 @@ const SettingsModal: React.FC<SettingsModalProps> = ({ settings, onUpdate, onClo
           </div>
         </div>
 
-        <div className="p-6 bg-slate-50 border-t border-slate-200 flex justify-end">
+        <div className="p-6 bg-slate-50 border-t border-slate-200 flex justify-end flex-shrink-0">
           <button
             onClick={onClose}
             className="bg-slate-800 text-white px-8 py-3 rounded-2xl font-bold hover:bg-slate-900 shadow-lg shadow-slate-200 transition-all uppercase tracking-widest text-[10px]"

components/VoiceSession.tsx

@@ -1,81 +1,62 @@
 
-import React, { useState, useRef, useEffect, useCallback } from 'react';
-import { Scenario, UserSettings, Message, AnalysisResult } from '../types';
-import { GoogleGenAI, LiveServerMessage, Modality } from '@google/genai';
-import { Mic, MicOff, PhoneOff, MessageSquare, BrainCircuit, Flag, Loader2 } from 'lucide-react';
-import { SYSTEM_ANALYSIS_PROMPT, SYSTEM_SUMMARY_ANALYSIS_PROMPT, CBT_ANALYSIS_SCHEMA } from '../constants';
-import { floatTo16BitPCM, arrayBufferToBase64, base64ToUint8Array, decodeAudioData } from '../services/audioUtils';
+import React, { useState, useCallback } from 'react';
+import { Scenario, UserSettings, AnalysisResult } from '../types';
+import { GoogleGenAI } from '@google/genai';
+import { SYSTEM_SUMMARY_ANALYSIS_PROMPT, CBT_ANALYSIS_SCHEMA } from '../constants';
+import { useLiveSession } from '../hooks/useLiveSession';
+import { AlertCircle, Settings2, X, BrainCircuit, Zap, Info } from 'lucide-react';
 
 // Sub-components
 import AudioVisualizer from './AudioVisualizer';
 import TranscriptPanel from './TranscriptPanel';
 import LiveInsightPanel from './LiveInsightPanel';
 import SessionReport from './SessionReport';
+import ConnectionState from './VoiceSession/ConnectionState';
+import AnalyzingState from './VoiceSession/AnalyzingState';
+import VoiceHeader from './VoiceSession/VoiceHeader';
+import VoiceControls from './VoiceSession/VoiceControls';
+import AudioDeviceSelector from './AudioDeviceSelector';
 
 interface VoiceSessionProps {
   scenario: Scenario;
   onExit: () => void;
   voiceSettings: UserSettings;
+  onUpdateSettings: (settings: UserSettings) => void;
 }
 
-// Manual encoding helper as per guidelines
-function encode(bytes: Uint8Array) {
-  let binary = '';
-  const len = bytes.byteLength;
-  for (let i = 0; i < len; i++) {
-    binary += String.fromCharCode(bytes[i]);
-  }
-  return btoa(binary);
-}
-
-// Manual decoding helper as per guidelines
-function decode(base64: string) {
-  const binaryString = atob(base64);
-  const len = binaryString.length;
-  const bytes = new Uint8Array(len);
-  for (let i = 0; i < len; i++) {
-    bytes[i] = binaryString.charCodeAt(i);
-  }
-  return bytes;
-}
-
-const VoiceSession: React.FC<VoiceSessionProps> = ({ scenario, onExit, voiceSettings }) => {
-  const [isMuted, setIsMuted] = useState(false);
+const VoiceSession: React.FC<VoiceSessionProps> = ({ scenario, onExit, voiceSettings, onUpdateSettings }) => {
   const [showTranscript, setShowTranscript] = useState(false);
-  const [messages, setMessages] = useState<Message[]>([]);
-  const [status, setStatus] = useState<'connecting' | 'active' | 'analyzing' | 'finished'>('connecting');
-  const [audioLevel, setAudioLevel] = useState(0);
-  const [isAiSpeaking, setIsAiSpeaking] = useState(false);
-
-  // Analysis States
-  const [liveInsight, setLiveInsight] = useState<AnalysisResult | null>(null);
-  const [isAnalyzingTurn, setIsAnalyzingTurn] = useState(false);
+  const [showDeviceSelector, setShowDeviceSelector] = useState(false);
+  const [hasStarted, setHasStarted] = useState(false);
   const [finalReport, setFinalReport] = useState<AnalysisResult | null>(null);
 
-  // Refs for Audio & Live API
-  const sessionPromiseRef = useRef<Promise<any> | null>(null);
-  const inputAudioCtxRef = useRef<AudioContext | null>(null);
-  const outputAudioCtxRef = useRef<AudioContext | null>(null);
-  const nextStartTimeRef = useRef<number>(0);
-  const audioSourcesRef = useRef<Set<AudioBufferSourceNode>>(new Set());
-  const streamRef = useRef<MediaStream | null>(null);
-  const analysisChatRef = useRef<any>(null);
+  const {
+    status,
+    setStatus,
+    isMuted,
+    toggleMute,
+    audioLevel,
+    aiAudioLevel,
+    isAiSpeaking,
+    isUserSpeaking,
+    messages,
+    liveInsight,
+    isAnalyzingTurn,
+    isSilenceDetected,
+    sessionPromiseRef,
+    startSession
+  } = useLiveSession(scenario, voiceSettings);
 
-  // Transcription buffers
-  const currentInputTranscription = useRef('');
-  const currentOutputTranscription = useRef('');
+  const activeLevel = isAiSpeaking ? aiAudioLevel : audioLevel;
 
-  const stopAllAudio = useCallback(() => {
-    audioSourcesRef.current.forEach(source => {
-      try { source.stop(); } catch (e) {}
-    });
-    audioSourcesRef.current.clear();
-    nextStartTimeRef.current = 0;
-  }, []);
+  const handleStart = useCallback(() => {
+    setHasStarted(true);
+    startSession();
+  }, [startSession]);
 
-  const handleFinishSession = async () => {
+  const handleFinishSession = useCallback(async () => {
     setStatus('analyzing');
-    // Close live session
+    
     if (sessionPromiseRef.current) {
       sessionPromiseRef.current.then(session => session.close());
     }
@@ -107,182 +88,10 @@ SCENARIO CONTEXT: ${scenario.title} - ${scenario.description}`;
       console.error("Post-session analysis failure", err);
       onExit();
     }
-  };
-
-  useEffect(() => {
-    const ai = new GoogleGenAI({ apiKey: process.env.API_KEY });
-
-    // Setup Analysis Model for Live Insights
-    analysisChatRef.current = ai.chats.create({
-      model: 'gemini-3-flash-preview',
-      config: {
-        systemInstruction: `${SYSTEM_ANALYSIS_PROMPT}\nSCENARIO: ${scenario.title}\nFOCUS: ${scenario.cbtFocus.join(', ')}`,
-        responseMimeType: 'application/json',
-        responseSchema: CBT_ANALYSIS_SCHEMA,
-      }
-    });
-
-    const init = async () => {
-      try {
-        inputAudioCtxRef.current = new (window.AudioContext || (window as any).webkitAudioContext)({ sampleRate: 16000 });
-        outputAudioCtxRef.current = new (window.AudioContext || (window as any).webkitAudioContext)({ sampleRate: 24000 });
-        
-        const stream = await navigator.mediaDevices.getUserMedia({ audio: true });
-        streamRef.current = stream;
-
-        const sessionPromise = ai.live.connect({
-          model: 'gemini-2.5-flash-native-audio-preview-09-2025',
-          callbacks: {
-            onopen: () => {
-              setStatus('active');
-              const source = inputAudioCtxRef.current!.createMediaStreamSource(stream);
-              const scriptProcessor = inputAudioCtxRef.current!.createScriptProcessor(4096, 1, 1);
-              
-              scriptProcessor.onaudioprocess = (e) => {
-                const inputData = e.inputBuffer.getChannelData(0);
-                
-                // Calculate simple audio level for visualizer
-                let sum = 0;
-                for (let i = 0; i < inputData.length; i++) sum += inputData[i] * inputData[i];
-                setAudioLevel(Math.sqrt(sum / inputData.length) * 100);
-
-                if (isMuted) return;
-
-                const pcm16 = floatTo16BitPCM(inputData);
-                const base64 = encode(new Uint8Array(pcm16));
-                
-                sessionPromise.then(session => {
-                  session.sendRealtimeInput({ 
-                    media: { data: base64, mimeType: 'audio/pcm;rate=16000' } 
-                  });
-                });
-              };
-
-              source.connect(scriptProcessor);
-              scriptProcessor.connect(inputAudioCtxRef.current!.destination);
-            },
-            onmessage: async (message: LiveServerMessage) => {
-              // Handle Transcriptions
-              if (message.serverContent?.outputTranscription) {
-                currentOutputTranscription.current += message.serverContent.outputTranscription.text;
-              } else if (message.serverContent?.inputTranscription) {
-                currentInputTranscription.current += message.serverContent.inputTranscription.text;
-              }
-
-              if (message.serverContent?.turnComplete) {
-                const userText = currentInputTranscription.current;
-                const modelText = currentOutputTranscription.current;
-
-                if (userText) {
-                  const userMsg: Message = { id: Date.now().toString(), role: 'user', text: userText, timestamp: new Date() };
-                  setMessages(prev => [...prev, userMsg]);
-                  
-                  // Trigger Analysis
-                  if (analysisChatRef.current && modelText) {
-                    setIsAnalyzingTurn(true);
-                    analysisChatRef.current.sendMessage({ message: `User: "${userText}"\nAI: "${modelText}"` })
-                      .then((res: any) => {
-                        try { if (res.text) setLiveInsight(JSON.parse(res.text)); }
-                        catch(e) {} finally { setIsAnalyzingTurn(false); }
-                      });
-                  }
-                }
-                
-                if (modelText) {
-                  setMessages(prev => [...prev, { id: (Date.now()+1).toString(), role: 'model', text: modelText, timestamp: new Date() }]);
-                }
-
-                currentInputTranscription.current = '';
-                currentOutputTranscription.current = '';
-              }
-
-              // Handle Audio Output
-              const audioBase64 = message.serverContent?.modelTurn?.parts[0]?.inlineData?.data;
-              if (audioBase64) {
-                setIsAiSpeaking(true);
-                const audioCtx = outputAudioCtxRef.current!;
-                nextStartTimeRef.current = Math.max(nextStartTimeRef.current, audioCtx.currentTime);
-                
-                const buffer = await decodeAudioData(decode(audioBase64), audioCtx, 24000, 1);
-                const source = audioCtx.createBufferSource();
-                source.buffer = buffer;
-                source.connect(audioCtx.destination);
-                
-                source.onended = () => {
-                  audioSourcesRef.current.delete(source);
-                  if (audioSourcesRef.current.size === 0) setIsAiSpeaking(false);
-                };
-                
-                source.start(nextStartTimeRef.current);
-                nextStartTimeRef.current += buffer.duration;
-                audioSourcesRef.current.add(source);
-              }
-
-              if (message.serverContent?.interrupted) {
-                stopAllAudio();
-                setIsAiSpeaking(false);
-              }
-            },
-            onclose: () => console.log("Live session closed"),
-            onerror: (e) => console.error("Live API error", e)
-          },
-          config: {
-            responseModalities: [Modality.AUDIO],
-            speechConfig: {
-              voiceConfig: { prebuiltVoiceConfig: { voiceName: voiceSettings.voiceName } }
-            },
-            systemInstruction: `
-              ${scenario.systemInstruction}
-              
-              VIRTUAL REALITY ROLEPLAY PROTOCOL:
-              1. Stay strictly in character.
-              2. DO NOT provide advice or analysis within the conversation.
-              3. React naturally to the user's voice and emotional tone.
-            `,
-            inputAudioTranscription: {},
-            outputAudioTranscription: {}
-          }
-        });
-
-        sessionPromiseRef.current = sessionPromise;
-      } catch (err) {
-        console.error("Initialization failed", err);
-      }
-    };
-
-    init();
-
-    return () => {
-      stopAllAudio();
-      if (streamRef.current) streamRef.current.getTracks().forEach(t => t.stop());
-      if (inputAudioCtxRef.current) inputAudioCtxRef.current.close();
-      if (outputAudioCtxRef.current) outputAudioCtxRef.current.close();
-      if (sessionPromiseRef.current) sessionPromiseRef.current.then(s => s.close());
-    };
-  }, [scenario, voiceSettings, stopAllAudio, isMuted]);
-
-  if (status === 'connecting') {
-    return (
-      <div className="flex flex-col items-center justify-center h-full text-slate-800 animate-pulse">
-        <Loader2 size={48} className="animate-spin text-teal-600 mb-4" />
-        <p className="font-bold uppercase tracking-widest text-xs">Opening Neural Bridge...</p>
-      </div>
-    );
-  }
-
-  if (status === 'analyzing') {
-    return (
-      <div className="flex flex-col items-center justify-center h-full text-slate-800">
-        <div className="bg-white p-12 rounded-full shadow-lg border border-teal-100 mb-8 relative">
-           <BrainCircuit size={64} className="text-teal-600 animate-pulse" />
-           <div className="absolute inset-0 border-4 border-teal-500 border-t-transparent rounded-full animate-spin"></div>
-        </div>
-        <h2 className="text-2xl font-bold mb-2">Generating Report</h2>
-        <p className="text-slate-500 text-center max-w-sm">Synthesizing vocal patterns and cognitive restructuring evidence...</p>
-      </div>
-    );
-  }
+  }, [messages, scenario, setStatus, sessionPromiseRef, onExit]);
 
+  if (status === 'connecting') return <ConnectionState />;
+  if (status === 'analyzing') return <AnalyzingState />;
   if (status === 'finished' && finalReport) {
     return <SessionReport analysis={finalReport} onExit={onExit} />;
   }
@@ -291,27 +100,85 @@ SCENARIO CONTEXT: ${scenario.title} - ${scenario.description}`;
     <div className="flex flex-col lg:flex-row h-full gap-4 relative overflow-hidden">
       {/* Main Interaction Area */}
       <div className="flex-grow bg-slate-900 rounded-3xl overflow-hidden flex flex-col relative shadow-2xl border border-white/5">
+        {/* Animated Background Aura */}
         <div className="absolute inset-0 overflow-hidden pointer-events-none opacity-20">
           <div className={`absolute top-1/2 left-1/2 -translate-x-1/2 -translate-y-1/2 w-[80%] h-[80%] rounded-full blur-[100px] transition-all duration-1000 ${isAiSpeaking ? 'bg-blue-500 scale-110' : 'bg-teal-500 scale-100'}`}></div>
         </div>
 
-        <div className="p-8 flex justify-between items-center relative z-10">
-          <div className="flex items-center gap-4">
-            <button onClick={onExit} className="p-3 bg-white/5 hover:bg-white/10 rounded-2xl text-white/50 hover:text-white transition-all">
-              <PhoneOff size={20} />
-            </button>
-            <div>
-              <h2 className="text-white font-bold text-lg">{scenario.title}</h2>
-              <p className="text-teal-400 text-[10px] font-black uppercase tracking-widest">Active Roleplay Session</p>
-            </div>
-          </div>
-          <button onClick={handleFinishSession} className="bg-teal-600 hover:bg-teal-700 text-white px-6 py-2.5 rounded-xl text-[10px] font-black uppercase tracking-widest transition-all shadow-lg shadow-teal-900/40 flex items-center gap-2">
-            <Flag size={14} /> Finish
-          </button>
-        </div>
+        <VoiceHeader 
+          title={scenario.title} 
+          onExit={onExit} 
+          onFinish={handleFinishSession} 
+        />
 
         <div className="flex-grow flex flex-col items-center justify-center p-12 relative z-10">
-          <AudioVisualizer level={audioLevel} active={true} isAiSpeaking={isAiSpeaking} />
+          {!hasStarted && status === 'active' ? (
+            <div className="flex flex-col items-center animate-in fade-in zoom-in duration-700">
+              <div className="w-24 h-24 bg-teal-500/10 rounded-full flex items-center justify-center mb-8 border border-teal-500/20 relative">
+                <div className="absolute inset-0 bg-teal-500/20 rounded-full animate-ping"></div>
+                <BrainCircuit size={40} className="text-teal-400 relative z-10" />
+              </div>
+              <h3 className="text-2xl font-bold text-white mb-2">Neural Link Established</h3>
+              <p className="text-slate-400 text-sm mb-8 max-w-xs text-center leading-relaxed">
+                The simulation is ready. Press start to begin your interaction with <strong>{scenario.characterName}</strong>.
+              </p>
+              
+              <div className="bg-white/5 border border-white/10 rounded-2xl p-4 mb-8 flex items-center gap-3 max-w-sm">
+                <div className="bg-teal-500/20 p-2 rounded-lg">
+                  <Info size={16} className="text-teal-400" />
+                </div>
+                <p className="text-[11px] text-slate-300 leading-relaxed">
+                  <strong>Greeting Hint:</strong> Say "Hello {scenario.characterName}" or just wait for them to speak first.
+                </p>
+              </div>
+
+              <button 
+                onClick={handleStart}
+                className="bg-teal-600 hover:bg-teal-500 text-white px-12 py-4 rounded-2xl font-bold transition-all shadow-xl shadow-teal-900/20 uppercase tracking-widest text-sm flex items-center gap-3"
+              >
+                <Zap size={18} fill="currentColor" />
+                Start Session
+              </button>
+            </div>
+          ) : (
+            <>
+              {isSilenceDetected && !isMuted && (
+                <div className="absolute top-8 left-1/2 -translate-x-1/2 w-full max-w-md animate-in slide-in-from-top-4 duration-500">
+                  <div className="bg-amber-500/90 backdrop-blur-md border border-amber-400 text-white p-4 rounded-2xl shadow-xl flex items-start gap-4">
+                    <div className="bg-white/20 p-2 rounded-xl">
+                      <AlertCircle size={20} />
+                    </div>
+                    <div className="flex-grow">
+                      <h4 className="text-sm font-bold">No Audio Detected</h4>
+                      <p className="text-xs text-white/80 mt-1 leading-relaxed">We can't hear you. Please check your microphone or select a different input device.</p>
+                      <button 
+                        onClick={() => setShowDeviceSelector(true)}
+                        className="mt-3 bg-white text-amber-600 px-4 py-1.5 rounded-lg text-[10px] font-black uppercase tracking-widest hover:bg-amber-50 transition-colors"
+                      >
+                        Change Input Device
+                      </button>
+                    </div>
+                  </div>
+                </div>
+              )}
+
+              {/* Speaker Indicator Badge */}
+              <div className="mb-8 flex flex-col items-center">
+                <div className={`px-4 py-1.5 rounded-full border transition-all duration-500 flex items-center gap-2 ${
+                  isAiSpeaking 
+                    ? 'bg-blue-500/20 border-blue-400/30 text-blue-300' 
+                    : (isUserSpeaking ? 'bg-teal-500/20 border-teal-400/30 text-teal-300' : 'bg-white/5 border-white/10 text-white/40')
+                }`}>
+                  <div className={`w-2 h-2 rounded-full ${
+                    isAiSpeaking ? 'bg-blue-400 animate-pulse' : (isUserSpeaking ? 'bg-teal-400 animate-pulse' : 'bg-white/20')
+                  }`} />
+                  <span className="text-[10px] font-black uppercase tracking-widest">
+                    {isAiSpeaking ? 'AI Speaking' : (isUserSpeaking ? 'You Speaking' : 'Waiting...')}
+                  </span>
+                </div>
+              </div>
+
+              <AudioVisualizer level={activeLevel} active={true} isAiSpeaking={isAiSpeaking} />
               
               <div className="mt-12 text-center">
                 <p className={`text-sm transition-all duration-500 font-light ${isAiSpeaking ? 'text-blue-300' : 'text-teal-300'}`}>
@@ -319,23 +186,49 @@ SCENARIO CONTEXT: ${scenario.title} - ${scenario.description}`;
                 </p>
                 <p className="text-[10px] text-white/30 uppercase font-bold tracking-[0.3em] mt-4">Clinical Fidelity Level: 99.8%</p>
               </div>
+            </>
+          )}
         </div>
 
-        <div className="p-8 flex justify-center gap-6 relative z-10 bg-black/20 backdrop-blur-md">
-          <button 
-            onClick={() => setIsMuted(!isMuted)}
-            className={`p-5 rounded-full transition-all ${isMuted ? 'bg-rose-600 text-white' : 'bg-white/10 text-white hover:bg-white/20'}`}
-          >
-            {isMuted ? <MicOff size={24} /> : <Mic size={24} />}
-          </button>
-          <button 
-            onClick={() => setShowTranscript(!showTranscript)}
-            className={`p-5 rounded-full transition-all ${showTranscript ? 'bg-teal-600 text-white' : 'bg-white/10 text-white hover:bg-white/20'}`}
-          >
-            <MessageSquare size={24} />
+        {/* Device Selector Overlay */}
+        {showDeviceSelector && (
+          <div className="absolute inset-0 z-50 bg-slate-900/80 backdrop-blur-sm flex items-center justify-center p-6 animate-in fade-in duration-300">
+            <div className="bg-white rounded-3xl p-6 w-full max-w-sm shadow-2xl border border-slate-100">
+              <div className="flex justify-between items-center mb-6">
+                <div className="flex items-center gap-3">
+                  <div className="bg-slate-800 p-2 rounded-xl text-white">
+                    <Settings2 size={18} />
+                  </div>
+                  <h3 className="font-bold text-slate-800">Audio Input</h3>
+                </div>
+                <button onClick={() => setShowDeviceSelector(false)} className="p-2 hover:bg-slate-100 rounded-xl transition-colors text-slate-400">
+                  <X size={20} />
                 </button>
               </div>
               
+              <AudioDeviceSelector 
+                selectedDeviceId={voiceSettings.preferredAudioDeviceId}
+                onSelect={(deviceId) => {
+                  onUpdateSettings({ ...voiceSettings, preferredAudioDeviceId: deviceId });
+                  // Don't close immediately so user sees the checkmark
+                  setTimeout(() => setShowDeviceSelector(false), 300);
+                }}
+              />
+              
+              <p className="text-[10px] text-slate-400 mt-6 leading-relaxed italic">
+                Changing your input device will restart the current neural link.
+              </p>
+            </div>
+          </div>
+        )}
+
+        <VoiceControls 
+          isMuted={isMuted} 
+          onToggleMute={toggleMute} 
+          showTranscript={showTranscript} 
+          onToggleTranscript={() => setShowTranscript(prev => !prev)} 
+        />
+
         {showTranscript && <TranscriptPanel messages={messages} onClose={() => setShowTranscript(false)} />}
       </div>
 

components/VoiceSession/AnalyzingState.tsx

@@ -0,0 +1,16 @@
+
+import React from 'react';
+import { BrainCircuit } from 'lucide-react';
+
+const AnalyzingState: React.FC = () => (
+  <div className="flex flex-col items-center justify-center h-full text-slate-800">
+    <div className="bg-white p-12 rounded-full shadow-lg border border-teal-100 mb-8 relative">
+       <BrainCircuit size={64} className="text-teal-600 animate-pulse" />
+       <div className="absolute inset-0 border-4 border-teal-500 border-t-transparent rounded-full animate-spin"></div>
+    </div>
+    <h2 className="text-2xl font-bold mb-2">Generating Report</h2>
+    <p className="text-slate-500 text-center max-w-sm">Synthesizing vocal patterns and cognitive restructuring evidence...</p>
+  </div>
+);
+
+export default React.memo(AnalyzingState);

components/VoiceSession/ConnectionState.tsx

@@ -0,0 +1,12 @@
+
+import React from 'react';
+import { Loader2 } from 'lucide-react';
+
+const ConnectionState: React.FC = () => (
+  <div className="flex flex-col items-center justify-center h-full text-slate-800 animate-pulse">
+    <Loader2 size={48} className="animate-spin text-teal-600 mb-4" />
+    <p className="font-bold uppercase tracking-widest text-xs">Opening Neural Bridge...</p>
+  </div>
+);
+
+export default React.memo(ConnectionState);

components/VoiceSession/VoiceControls.tsx

@@ -0,0 +1,34 @@
+
+import React from 'react';
+import { Mic, MicOff, MessageSquare } from 'lucide-react';
+
+interface VoiceControlsProps {
+  isMuted: boolean;
+  onToggleMute: () => void;
+  showTranscript: boolean;
+  onToggleTranscript: () => void;
+}
+
+const VoiceControls: React.FC<VoiceControlsProps> = ({ 
+  isMuted, 
+  onToggleMute, 
+  showTranscript, 
+  onToggleTranscript 
+}) => (
+  <div className="p-8 flex justify-center gap-6 relative z-10 bg-black/20 backdrop-blur-md">
+    <button 
+      onClick={onToggleMute}
+      className={`p-5 rounded-full transition-all ${isMuted ? 'bg-rose-600 text-white' : 'bg-white/10 text-white hover:bg-white/20'}`}
+    >
+      {isMuted ? <MicOff size={24} /> : <Mic size={24} />}
+    </button>
+    <button 
+      onClick={onToggleTranscript}
+      className={`p-5 rounded-full transition-all ${showTranscript ? 'bg-teal-600 text-white' : 'bg-white/10 text-white hover:bg-white/20'}`}
+    >
+      <MessageSquare size={24} />
+    </button>
+  </div>
+);
+
+export default React.memo(VoiceControls);

components/VoiceSession/VoiceHeader.tsx

@@ -0,0 +1,28 @@
+
+import React from 'react';
+import { PhoneOff, Flag } from 'lucide-react';
+
+interface VoiceHeaderProps {
+  title: string;
+  onExit: () => void;
+  onFinish: () => void;
+}
+
+const VoiceHeader: React.FC<VoiceHeaderProps> = ({ title, onExit, onFinish }) => (
+  <div className="p-8 flex justify-between items-center relative z-10">
+    <div className="flex items-center gap-4">
+      <button onClick={onExit} className="p-3 bg-white/5 hover:bg-white/10 rounded-2xl text-white/50 hover:text-white transition-all">
+        <PhoneOff size={20} />
+      </button>
+      <div>
+        <h2 className="text-white font-bold text-lg">{title}</h2>
+        <p className="text-teal-400 text-[10px] font-black uppercase tracking-widest">Active Roleplay Session</p>
+      </div>
+    </div>
+    <button onClick={onFinish} className="bg-teal-600 hover:bg-teal-700 text-white px-6 py-2.5 rounded-xl text-[10px] font-black uppercase tracking-widest transition-all shadow-lg shadow-teal-900/40 flex items-center gap-2">
+      <Flag size={14} /> Finish
+    </button>
+  </div>
+);
+
+export default React.memo(VoiceHeader);

constants.ts

@@ -112,36 +112,40 @@ export const SCENARIOS: Scenario[] = [
   {
     id: 's1',
     title: "The Silent Friend",
+    characterName: "Alex",
     description: "You sent a text to a close friend hours ago and haven't heard back. You're starting to imagine they're angry with you or that you've done something wrong.",
     category: 'Relationships',
     difficulty: 'Beginner',
-    systemInstruction: "You are a busy friend who just hasn't had a chance to reply yet. You are friendly and non-confrontational. If asked, you explain you were just preoccupied with chores.",
+    systemInstruction: "You are Alex, a busy friend who just hasn't had a chance to reply yet. You are friendly and non-confrontational. If asked, you explain you were just preoccupied with chores.",
     initialMessage: "Hey! Sorry I'm just getting back to you, it's been a crazy day. What's up?",
     cbtFocus: ["Mind Reading", "Fortune Telling"]
   },
   {
     id: 's2',
     title: "Critical Feedback",
+    characterName: "Sarah",
     description: "Your manager asks for a quick sync. You immediately assume the worst about your performance and upcoming review.",
     category: 'Workplace',
     difficulty: 'Intermediate',
-    systemInstruction: "You are a professional manager. You have one piece of constructive feedback regarding a recent report, but overall you're happy with the user's performance. INTERNAL CBT LOGIC: If the user catastrophizes, reassure them professionally but maintain your feedback.",
+    systemInstruction: "You are Sarah, a professional manager. You have one piece of constructive feedback regarding a recent report, but overall you're happy with the user's performance. INTERNAL CBT LOGIC: If the user catastrophizes, reassure them professionally but maintain your feedback.",
     initialMessage: "Hi there, thanks for jumping on. I wanted to chat briefly about the Q3 project report.",
     cbtFocus: ["Catastrophizing", "All-or-Nothing Thinking"]
   },
   {
     id: 's3',
     title: "The Social Spotlight",
+    characterName: "David",
     description: "You're at a networking event and you just made a small slip-up in a conversation. You feel like everyone noticed and is judging you.",
     category: 'Social Anxiety',
     difficulty: 'Advanced',
-    systemInstruction: "You are an attendee at a networking event. You are polite and didn't even notice the user's minor slip-up. You are focused on professional exchange.",
+    systemInstruction: "You are David, an attendee at a networking event. You are polite and didn't even notice the user's minor slip-up. You are focused on professional exchange.",
     initialMessage: "That's an interesting point about the industry trends. So, how did you get started in this field?",
     cbtFocus: ["Spotlight Effect", "Emotional Reasoning"]
   },
   {
     id: 's4',
     title: "Inner Critic Echo",
+    characterName: "The Critic",
     description: "A minor mistake at home triggers a spiral of self-deprecating thoughts. Practice internal cognitive restructuring by talking back to your personified inner critic.",
     category: 'Self-Talk',
     difficulty: 'Beginner',
@@ -152,6 +156,7 @@ export const SCENARIOS: Scenario[] = [
   {
     id: 's5',
     title: "Booking an Appointment",
+    characterName: "Receptionist",
     description: "You need to call a busy medical clinic to book a follow-up. You're worried about being a nuisance or stuttering during the call.",
     category: 'Social Anxiety',
     difficulty: 'Beginner',
@@ -162,6 +167,7 @@ export const SCENARIOS: Scenario[] = [
   {
     id: 's6',
     title: "The Defective Return",
+    characterName: "Store Clerk",
     description: "You bought an expensive espresso machine that is leaking. You're at the store to return it, but you're afraid the clerk will be dismissive or think you're lying.",
     category: 'Social Anxiety',
     difficulty: 'Intermediate',
@@ -172,76 +178,84 @@ export const SCENARIOS: Scenario[] = [
   {
     id: 's7',
     title: "The Unpaid Debt",
+    characterName: "Jordan",
     description: "A close friend borrowed $200 three months ago and hasn't mentioned it since. You need the money for bills but feel guilty for asking.",
     category: 'Relationships',
     difficulty: 'Advanced',
-    systemInstruction: "You are a well-meaning but somewhat forgetful friend. You value the friendship and haven't intentionally avoided the debt; you just genuinely forgot. INTERNAL CBT LOGIC: If the user uses 'Should Statements' about themselves (I shouldn't have to ask), don't get defensive, but wait for them to express the need directly.",
+    systemInstruction: "You are Jordan, a well-meaning but somewhat forgetful friend. You value the friendship and haven't intentionally avoided the debt; you just genuinely forgot. INTERNAL CBT LOGIC: If the user uses 'Should Statements' about themselves (I shouldn't have to ask), don't get defensive, but wait for them to express the need directly.",
     initialMessage: "Hey! It was so good to see you at brunch last week. What's on your mind today?",
     cbtFocus: ["Maladaptive Guilt", "Should Statements"]
   },
   {
     id: 's8',
     title: "The Salary Discussion",
+    characterName: "Mr. Henderson",
     description: "You've been exceeding all your targets for a year. You've prepared a case for a raise, but you're battling thoughts that you're being 'greedy' or 'ungrateful'.",
     category: 'Workplace',
     difficulty: 'Advanced',
-    systemInstruction: "You are a firm but fair Department Head. You have a limited budget but respect high performance. INTERNAL CBT LOGIC: If the user sounds apologetic or uses 'Shoulds', push back slightly on the budget. If they use objective evidence and stay regulated, be more collaborative.",
+    systemInstruction: "You are Mr. Henderson, a firm but fair Department Head. You have a limited budget but respect high performance. INTERNAL CBT LOGIC: If the user sounds apologetic or uses 'Shoulds', push back slightly on the budget. If they use objective evidence and stay regulated, be more collaborative.",
     initialMessage: "Thanks for coming in. I know you wanted to discuss your compensation. What's your proposal?",
     cbtFocus: ["Should Statements", "All-or-Nothing Thinking"]
   },
   {
     id: 's9',
     title: "The Deadline Slip",
+    characterName: "Marcus",
     description: "You missed a major deadline because you were waiting on a partner's input. You feel like a total failure and are sure your boss will fire you.",
     category: 'Workplace',
     difficulty: 'Intermediate',
-    systemInstruction: "You are a result-oriented Team Lead. You are disappointed the deadline was missed but want to solve the problem and prevent a recurrence. INTERNAL CBT LOGIC: If the user uses 'Labeling' (I am a failure), focus them back on the specific behavior and the external variables.",
+    systemInstruction: "You are Marcus, a result-oriented Team Lead. You are disappointed the deadline was missed but want to solve the problem and prevent a recurrence. INTERNAL CBT LOGIC: If the user uses 'Labeling' (I am a failure), focus them back on the specific behavior and the external variables.",
     initialMessage: "The client is asking where the Q1 projection is. We missed the 9 AM cutoff. What happened?",
     cbtFocus: ["Labeling", "Overgeneralization"]
   },
   {
     id: 's10',
     title: "The Social 'No'",
+    characterName: "Chloe",
     description: "A friend has invited you to a high-energy party. You are exhausted and need rest, but you're sure they will stop liking you if you don't attend.",
     category: 'Social Anxiety',
     difficulty: 'Intermediate',
-    systemInstruction: "You are an extroverted friend who is excited about a party. You want the user to come because you enjoy their company, but you aren't trying to be manipulative. INTERNAL CBT LOGIC: If the user 'Mind Reads' (You're going to be mad at me), respond with slight confusion about why they'd think that.",
+    systemInstruction: "You are Chloe, an extroverted friend who is excited about a party. You want the user to come because you enjoy their company, but you aren't trying to be manipulative. INTERNAL CBT LOGIC: If the user 'Mind Reads' (You're going to be mad at me), respond with slight confusion about why they'd think that.",
     initialMessage: "You are definitely coming to Sarah's party tonight, right? Everyone is going to be there!",
     cbtFocus: ["Mind Reading", "Fortune Telling"]
   },
   {
     id: 's11',
     title: "Intrusive Relative",
+    characterName: "Aunt Martha",
     description: "A relative is making critical comments about your career choices during a family dinner. Practice setting a boundary without spiraling into anger.",
     category: 'Relationships',
     difficulty: 'Advanced',
-    systemInstruction: "You are a critical, traditional-minded aunt/uncle. You think you're 'just being helpful' with your advice. INTERNAL CBT LOGIC: If the user sets a clear boundary, try to guilt-trip them slightly to see if they can maintain it.",
+    systemInstruction: "You are Aunt Martha, a critical, traditional-minded relative. You think you're 'just being helpful' with your advice. INTERNAL CBT LOGIC: If the user sets a clear boundary, try to guilt-trip them slightly to see if they can maintain it.",
     initialMessage: "I saw your latest post. Are you still doing that freelance work? It's been a while, shouldn't you look for something more... stable?",
     cbtFocus: ["Healthy Boundaries", "Gray Rock Method"]
   },
   {
     id: 's12',
     title: "The Job Interview",
+    characterName: "Ms. Sterling",
     description: "You're in the waiting room for a job you really want. Your mind is already 'Fortune Telling' that you will stutter and look incompetent.",
     category: 'Social Anxiety',
     difficulty: 'Advanced',
-    systemInstruction: "You are an HR Director at a top firm. You are professional, observant, and asking standard but probing questions. INTERNAL CBT LOGIC: If the user shows 'Fortune Telling' behaviors (pre-apologizing), maintain a neutral professional stance.",
+    systemInstruction: "You are Ms. Sterling, an HR Director at a top firm. You are professional, observant, and asking standard but probing questions. INTERNAL CBT LOGIC: If the user shows 'Fortune Telling' behaviors (pre-apologizing), maintain a neutral professional stance.",
     initialMessage: "Welcome. Please, have a seat. Why don't we start by you telling me about a time you handled a difficult conflict at work?",
     cbtFocus: ["Fortune Telling", "Catastrophizing"]
   },
   {
     id: 's13',
     title: "The Friend's Criticism",
+    characterName: "Leo",
     description: "A friend tells you that you've been 'acting distant' lately. Your immediate reaction is to take it as a personal attack on your character.",
     category: 'Relationships',
     difficulty: 'Intermediate',
-    systemInstruction: "You are a friend who feels a bit neglected and is expressing their feelings. You aren't attacking the user, just sharing your perspective. INTERNAL CBT LOGIC: If the user 'Personalizes' (I'm a bad friend), re-center the conversation on the specific dynamic.",
+    systemInstruction: "You are Leo, a friend who feels a bit neglected and is expressing their feelings. You aren't attacking the user, just sharing your perspective. INTERNAL CBT LOGIC: If the user 'Personalizes' (I'm a bad friend), re-center the conversation on the specific dynamic.",
     initialMessage: "I feel like we haven't really talked in weeks. Is everything okay? It feels like you've been avoiding my calls.",
     cbtFocus: ["Personalization", "Emotional Reasoning"]
   },
   {
     id: 's14',
     title: "The Unexpected Health Symptom",
+    characterName: "Anxiety",
     description: "You've noticed a small rash on your arm. Your mind has already jumped to a terminal illness. Practice radical acceptance and de-catastrophizing.",
     category: 'Self-Talk',
     difficulty: 'Advanced',

hooks/useLiveSession.ts

@@ -0,0 +1,276 @@
+
+import { useState, useRef, useEffect, useCallback } from 'react';
+import { GoogleGenAI, LiveServerMessage, Modality } from '@google/genai';
+import { Scenario, UserSettings, Message, AnalysisResult } from '../types';
+import { SYSTEM_ANALYSIS_PROMPT, CBT_ANALYSIS_SCHEMA } from '../constants';
+import { floatTo16BitPCM, encodeBase64, decodeBase64, decodeAudioData } from '../services/audioUtils';
+
+export type SessionStatus = 'connecting' | 'active' | 'analyzing' | 'finished';
+
+export function useLiveSession(scenario: Scenario, voiceSettings: UserSettings) {
+  const [status, setStatus] = useState<SessionStatus>('connecting');
+  const [isMuted, setIsMuted] = useState(false);
+  const [audioLevel, setAudioLevel] = useState(0);
+  const [aiAudioLevel, setAiAudioLevel] = useState(0);
+  const [isAiSpeaking, setIsAiSpeaking] = useState(false);
+  const [isUserSpeaking, setIsUserSpeaking] = useState(false);
+  const [messages, setMessages] = useState<Message[]>([]);
+  const [isSilenceDetected, setIsSilenceDetected] = useState(false);
+  
+  // Insights state
+  const [liveInsight, setLiveInsight] = useState<AnalysisResult | null>(null);
+  const [isAnalyzingTurn, setIsAnalyzingTurn] = useState(false);
+
+  // Refs for audio processing
+  const sessionPromiseRef = useRef<Promise<any> | null>(null);
+  const inputAudioCtxRef = useRef<AudioContext | null>(null);
+  const outputAudioCtxRef = useRef<AudioContext | null>(null);
+  const aiAnalyserRef = useRef<AnalyserNode | null>(null);
+  const nextStartTimeRef = useRef<number>(0);
+  const audioSourcesRef = useRef<Set<AudioBufferSourceNode>>(new Set());
+  const streamRef = useRef<MediaStream | null>(null);
+  const analysisChatRef = useRef<any>(null);
+  const silenceCheckTimerRef = useRef<NodeJS.Timeout | null>(null);
+  const aiLevelUpdateTimerRef = useRef<number | null>(null);
+
+  // Buffers for transcription
+  const currentInputTranscription = useRef('');
+  const currentOutputTranscription = useRef('');
+
+  const stopAllAudio = useCallback(() => {
+    audioSourcesRef.current.forEach(source => {
+      try { source.stop(); } catch (e) {}
+    });
+    audioSourcesRef.current.clear();
+    nextStartTimeRef.current = 0;
+    setAiAudioLevel(0);
+  }, []);
+
+  const toggleMute = useCallback(() => setIsMuted(prev => !prev), []);
+
+  useEffect(() => {
+    const ai = new GoogleGenAI({ apiKey: process.env.API_KEY });
+
+    // Setup Live Insights Chat
+    analysisChatRef.current = ai.chats.create({
+      model: 'gemini-3-flash-preview',
+      config: {
+        systemInstruction: `${SYSTEM_ANALYSIS_PROMPT}\nSCENARIO: ${scenario.title}\nFOCUS: ${scenario.cbtFocus.join(', ')}`,
+        responseMimeType: 'application/json',
+        responseSchema: CBT_ANALYSIS_SCHEMA,
+      }
+    });
+
+    const updateAiLevel = () => {
+      if (aiAnalyserRef.current && isAiSpeaking) {
+        const dataArray = new Uint8Array(aiAnalyserRef.current.frequencyBinCount);
+        aiAnalyserRef.current.getByteFrequencyData(dataArray);
+        let sum = 0;
+        for (let i = 0; i < dataArray.length; i++) sum += dataArray[i];
+        const avg = sum / dataArray.length;
+        setAiAudioLevel(avg * 0.8); // Scale for visualizer
+      } else {
+        setAiAudioLevel(0);
+      }
+      aiLevelUpdateTimerRef.current = requestAnimationFrame(updateAiLevel);
+    };
+
+    const connect = async () => {
+      try {
+        inputAudioCtxRef.current = new (window.AudioContext || (window as any).webkitAudioContext)({ sampleRate: 16000 });
+        outputAudioCtxRef.current = new (window.AudioContext || (window as any).webkitAudioContext)({ sampleRate: 24000 });
+        
+        aiAnalyserRef.current = outputAudioCtxRef.current.createAnalyser();
+        aiAnalyserRef.current.fftSize = 256;
+        aiAnalyserRef.current.connect(outputAudioCtxRef.current.destination);
+        
+        updateAiLevel();
+
+        const constraints: MediaStreamConstraints = { 
+          audio: voiceSettings.preferredAudioDeviceId 
+            ? { deviceId: { exact: voiceSettings.preferredAudioDeviceId } } 
+            : true 
+        };
+
+        const stream = await navigator.mediaDevices.getUserMedia(constraints);
+        streamRef.current = stream;
+
+        // Silence detection logic: If after 5 seconds of active session, 
+        // the max audio level seen is very low, flag it.
+        let maxLevelSeen = 0;
+        silenceCheckTimerRef.current = setTimeout(() => {
+          if (maxLevelSeen < 1.0) { // Threshold for silence
+            setIsSilenceDetected(true);
+          }
+        }, 6000);
+
+        const sessionPromise = ai.live.connect({
+          model: 'gemini-2.5-flash-native-audio-preview-09-2025',
+          callbacks: {
+            onopen: () => {
+              setStatus('active');
+              const source = inputAudioCtxRef.current!.createMediaStreamSource(stream);
+              const scriptProcessor = inputAudioCtxRef.current!.createScriptProcessor(4096, 1, 1);
+              
+              scriptProcessor.onaudioprocess = (e) => {
+                const inputData = e.inputBuffer.getChannelData(0);
+                
+                // Volume calculation
+                let sum = 0;
+                for (let i = 0; i < inputData.length; i++) sum += inputData[i] * inputData[i];
+                const level = Math.sqrt(sum / inputData.length) * 100;
+                setAudioLevel(level);
+                setIsUserSpeaking(level > 2.0);
+                
+                if (level > maxLevelSeen) maxLevelSeen = level;
+                if (level > 2.0 && isSilenceDetected) setIsSilenceDetected(false);
+
+                if (isMuted) return;
+
+                const pcm16 = floatTo16BitPCM(inputData);
+                const base64 = encodeBase64(new Uint8Array(pcm16));
+                
+                sessionPromise.then(session => {
+                  session.sendRealtimeInput({ 
+                    media: { data: base64, mimeType: 'audio/pcm;rate=16000' } 
+                  });
+                });
+              };
+
+              source.connect(scriptProcessor);
+              scriptProcessor.connect(inputAudioCtxRef.current!.destination);
+            },
+            onmessage: async (message: LiveServerMessage) => {
+              // Transcriptions
+              if (message.serverContent?.outputTranscription) {
+                currentOutputTranscription.current += message.serverContent.outputTranscription.text;
+              } else if (message.serverContent?.inputTranscription) {
+                currentInputTranscription.current += message.serverContent.inputTranscription.text;
+              }
+
+              if (message.serverContent?.turnComplete) {
+                const userText = currentInputTranscription.current;
+                const modelText = currentOutputTranscription.current;
+
+                if (userText) {
+                  setMessages(prev => [...prev, { id: Date.now().toString(), role: 'user', text: userText, timestamp: new Date() }]);
+                  
+                  if (analysisChatRef.current && modelText) {
+                    setIsAnalyzingTurn(true);
+                    analysisChatRef.current.sendMessage({ message: `User: "${userText}"\nAI: "${modelText}"` })
+                      .then((res: any) => {
+                        try { if (res.text) setLiveInsight(JSON.parse(res.text)); }
+                        catch(e) {} finally { setIsAnalyzingTurn(false); }
+                      });
+                  }
+                }
+                
+                if (modelText) {
+                  setMessages(prev => [...prev, { id: (Date.now()+1).toString(), role: 'model', text: modelText, timestamp: new Date() }]);
+                }
+
+                currentInputTranscription.current = '';
+                currentOutputTranscription.current = '';
+              }
+
+              // Audio Output
+              const audioBase64 = message.serverContent?.modelTurn?.parts[0]?.inlineData?.data;
+              if (audioBase64) {
+                setIsAiSpeaking(true);
+                const audioCtx = outputAudioCtxRef.current!;
+                nextStartTimeRef.current = Math.max(nextStartTimeRef.current, audioCtx.currentTime);
+                
+                const buffer = await decodeAudioData(decodeBase64(audioBase64), audioCtx, 24000, 1);
+                const source = audioCtx.createBufferSource();
+                source.buffer = buffer;
+                source.connect(aiAnalyserRef.current!);
+                
+                source.onended = () => {
+                  audioSourcesRef.current.delete(source);
+                  if (audioSourcesRef.current.size === 0) setIsAiSpeaking(false);
+                };
+                
+                source.start(nextStartTimeRef.current);
+                nextStartTimeRef.current += buffer.duration;
+                audioSourcesRef.current.add(source);
+              }
+
+              if (message.serverContent?.interrupted) {
+                stopAllAudio();
+                setIsAiSpeaking(false);
+              }
+            },
+            onclose: () => console.debug("Session closed"),
+            onerror: (e) => console.error("Session error", e)
+          },
+          config: {
+            responseModalities: [Modality.AUDIO],
+            speechConfig: {
+              voiceConfig: { prebuiltVoiceConfig: { voiceName: voiceSettings.voiceName } }
+            },
+            systemInstruction: `
+              ${scenario.systemInstruction}
+              
+              VOCAL REALISM PROTOCOL:
+              - Speak with natural human patterns (fillers like "um", "uh", "well...").
+              - Use brief hesitations when thinking or emotionally activated.
+              - Vary pace based on character emotion.
+              - Strictly in character; no clinical meta-feedback.
+            `,
+            inputAudioTranscription: {},
+            outputAudioTranscription: {}
+          }
+        });
+
+        sessionPromiseRef.current = sessionPromise;
+      } catch (err) {
+        console.error("Connect failed", err);
+      }
+    };
+
+    connect();
+
+    return () => {
+      stopAllAudio();
+      if (silenceCheckTimerRef.current) clearTimeout(silenceCheckTimerRef.current);
+      if (aiLevelUpdateTimerRef.current) cancelAnimationFrame(aiLevelUpdateTimerRef.current);
+      if (streamRef.current) streamRef.current.getTracks().forEach(t => t.stop());
+      if (inputAudioCtxRef.current) inputAudioCtxRef.current.close();
+      if (outputAudioCtxRef.current) outputAudioCtxRef.current.close();
+      if (sessionPromiseRef.current) sessionPromiseRef.current.then(s => s.close());
+    };
+  }, [scenario, voiceSettings, stopAllAudio, isMuted]);
+
+  return {
+    status,
+    setStatus,
+    isMuted,
+    toggleMute,
+    audioLevel,
+    aiAudioLevel,
+    isAiSpeaking,
+    isUserSpeaking,
+    messages,
+    liveInsight,
+    isAnalyzingTurn,
+    isSilenceDetected,
+    sessionPromiseRef,
+    startSession: () => {
+      if (sessionPromiseRef.current) {
+        sessionPromiseRef.current.then(session => {
+          // We send a "hidden" text input to the model to trigger its initial message
+          // The Live API supports sending text turns in the clientContent
+          session.send({
+            clientContent: {
+              turns: [{
+                role: 'user',
+                parts: [{ text: "Please start the scenario now. Greet me as your character." }]
+              }],
+              turnComplete: true
+            }
+          });
+        });
+      }
+    }
+  };
+}

index.html

@@ -31,8 +31,10 @@
   }
 }
 </script>
+<link rel="stylesheet" href="/index.css">
 </head>
   <body>
     <div id="root"></div>
-  </body>
+  <script type="module" src="/index.tsx"></script>
+</body>
 </html>

package.json

@@ -6,7 +6,8 @@
   "scripts": {
     "dev": "vite",
     "build": "vite build",
-    "preview": "vite preview"
+    "preview": "vite preview",
+    "lint": "tsc --noEmit"
   },
   "dependencies": {
     "react": "^19.2.3",

services/audioUtils.ts

@@ -1,4 +1,3 @@
-import { LiveServerMessage, Modality } from "@google/genai";
 
 // Convert Float32Array (Web Audio API) to PCM Int16 (Gemini API requirement)
 export function floatTo16BitPCM(float32Array: Float32Array): ArrayBuffer {
@@ -14,10 +13,9 @@ export function floatTo16BitPCM(float32Array: Float32Array): ArrayBuffer {
   return buffer;
 }
 
-// Base64 encoding for the payload
-export function arrayBufferToBase64(buffer: ArrayBuffer): string {
+// Manual encoding helper as per guidelines
+export function encodeBase64(bytes: Uint8Array): string {
   let binary = '';
-  const bytes = new Uint8Array(buffer);
   const len = bytes.byteLength;
   for (let i = 0; i < len; i++) {
     binary += String.fromCharCode(bytes[i]);
@@ -25,8 +23,8 @@ export function arrayBufferToBase64(buffer: ArrayBuffer): string {
   return btoa(binary);
 }
 
-// Convert Base64 string back to Uint8Array
-export function base64ToUint8Array(base64: string): Uint8Array {
+// Manual decoding helper as per guidelines
+export function decodeBase64(base64: string): Uint8Array {
   const binaryString = atob(base64);
   const len = binaryString.length;
   const bytes = new Uint8Array(len);
@@ -45,20 +43,15 @@ export async function decodeAudioData(
 ): Promise<AudioBuffer> {
   // Ensure the byte length is even for Int16Array
   if (data.byteLength % 2 !== 0) {
-      console.warn("Received odd byte length for PCM16 audio, trimming last byte.");
       data = data.subarray(0, data.byteLength - 1);
   }
 
-  // Use the underlying buffer, but handle offsets if the Uint8Array is a view
   const dataInt16 = new Int16Array(data.buffer, data.byteOffset, data.byteLength / 2);
-  
   const buffer = ctx.createBuffer(numChannels, dataInt16.length / numChannels, sampleRate);
 
   for (let channel = 0; channel < numChannels; channel++) {
     const channelData = buffer.getChannelData(channel);
-    // Determine step size if multiple channels (usually 1 for this API)
     for (let i = 0; i < dataInt16.length; i++) {
-      // Normalize Int16 to Float32 [-1.0, 1.0]
       channelData[i] = dataInt16[i] / 32768.0;
     }
   }

types.ts

@@ -8,12 +8,14 @@ export interface Scenario {
   systemInstruction: string;
   initialMessage: string;
   cbtFocus: string[];
+  characterName: string;
 }
 
 export interface UserSettings {
   voiceName: 'Puck' | 'Charon' | 'Kore' | 'Fenrir' | 'Zephyr';
   vocalStyle: string;
   genderPreference: 'Male' | 'Female' | 'Neutral';
+  preferredAudioDeviceId?: string;
 }
 
 export interface Message {