File size: 8,456 Bytes
c622774
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
import React, { useEffect, useState, useRef } from 'react';
import { Mic, X, MicOff, AlertCircle } from 'lucide-react';

export default function VoiceSessionModal({ isOpen, onClose, apiKey }) {
  const [status, setStatus] = useState('connecting'); // 'connecting', 'listening', 'speaking', 'error'
  const [errorMessage, setErrorMessage] = useState('');
  const [isMuted, setIsMuted] = useState(false);
  
  const wsRef = useRef(null);
  const audioContextRef = useRef(null);
  const playbackContextRef = useRef(null);
  const streamRef = useRef(null);
  const processorRef = useRef(null);
  const nextPlayTimeRef = useRef(0);
  const textTranscriptRef = useRef('');
  const [transcript, setTranscript] = useState('');

  // Helper: Convert ArrayBuffer to Base64
  const base64ArrayBuffer = (arrayBuffer) => {
    let binary = '';
    const bytes = new Uint8Array(arrayBuffer);
    const len = bytes.byteLength;
    for (let i = 0; i < len; i++) {
      binary += String.fromCharCode(bytes[i]);
    }
    return window.btoa(binary);
  };

  useEffect(() => {
    if (!isOpen) return;

    setStatus('connecting');
    setTranscript('');
    textTranscriptRef.current = '';

    // Determine WebSocket URL
    const protocol = window.location.protocol === 'https:' ? 'wss://' : 'ws://';
    const host = window.location.host === 'localhost:5173' ? 'localhost:8000' : window.location.host;
    const wsUrl = `${protocol}${host}/api/live-ws?api_key=${apiKey || ''}`;

    // Establish WebSocket Connection
    const ws = new WebSocket(wsUrl);
    wsRef.current = ws;

    ws.onopen = async () => {
      try {
        // Request Microphone access
        const stream = await navigator.mediaDevices.getUserMedia({ audio: true });
        streamRef.current = stream;

        // Initialize Audio contexts
        audioContextRef.current = new (window.AudioContext || window.webkitAudioContext)({ sampleRate: 16000 });
        playbackContextRef.current = new (window.AudioContext || window.webkitAudioContext)({ sampleRate: 24000 });
        nextPlayTimeRef.current = playbackContextRef.current.currentTime;

        // Capture Mic Input
        const source = audioContextRef.current.createMediaStreamSource(stream);
        const processor = audioContextRef.current.createScriptProcessor(2048, 1, 1);
        processorRef.current = processor;

        processor.onaudioprocess = (e) => {
          if (isMuted) return;

          const inputData = e.inputBuffer.getChannelData(0);
          // Convert Float32 to Int16 PCM
          const pcmData = new Int16Array(inputData.length);
          for (let i = 0; i < inputData.length; i++) {
            pcmData[i] = Math.max(-1, Math.min(1, inputData[i])) * 0x7FFF;
          }

          // Send chunk to server
          if (ws.readyState === WebSocket.OPEN) {
            const base64Audio = base64ArrayBuffer(pcmData.buffer);
            ws.send(JSON.stringify({ type: 'audio', data: base64Audio }));
          }
        };

        source.connect(processor);
        processor.connect(audioContextRef.current.destination);

        setStatus('listening');
      } catch (err) {
        console.error("Microphone access failed:", err);
        setStatus('error');
        setErrorMessage("Microphone access is required for voice session. Please allow mic permissions.");
      }
    };

    ws.onmessage = async (event) => {
      const message = JSON.parse(event.data);

      if (message.type === 'audio') {
        setStatus('speaking');
        
        // Decode base64 24kHz PCM back to Float32 for Web Audio playback
        const binary = window.atob(message.data);
        const bytes = new Uint8Array(binary.length);
        for (let i = 0; i < binary.length; i++) {
          bytes[i] = binary.charCodeAt(i);
        }

        const int16Data = new Int16Array(bytes.buffer);
        const float32Data = new Float32Array(int16Data.length);
        for (let i = 0; i < int16Data.length; i++) {
          float32Data[i] = int16Data[i] / 0x7FFF;
        }

        const pContext = playbackContextRef.current;
        if (pContext && pContext.state !== 'suspended') {
          const audioBuffer = pContext.createBuffer(1, float32Data.length, 24000);
          audioBuffer.getChannelData(0).set(float32Data);

          const bufferSource = pContext.createBufferSource();
          bufferSource.buffer = audioBuffer;
          bufferSource.connect(pContext.destination);

          // Gapless scheduling
          const startTime = Math.max(pContext.currentTime, nextPlayTimeRef.current);
          bufferSource.start(startTime);
          nextPlayTimeRef.current = startTime + audioBuffer.duration;
        }
      } else if (message.type === 'text') {
        // Handle incoming Socratic tutor speech transcription
        textTranscriptRef.current += message.data;
        setTranscript(textTranscriptRef.current);
      } else if (message.type === 'turn_complete') {
        setStatus('listening');
        textTranscriptRef.current = '';
      }
    };

    ws.onerror = (err) => {
      console.error("WebSocket error:", err);
      setStatus('error');
      setErrorMessage("Lost connection to Gemini Live server.");
    };

    ws.onclose = () => {
      setStatus('connecting');
    };

    return () => {
      // Clean up connections and audio context on unmount
      if (wsRef.current) wsRef.current.close();
      if (processorRef.current) processorRef.current.disconnect();
      if (streamRef.current) {
        streamRef.current.getTracks().forEach(track => track.stop());
      }
      if (audioContextRef.current) audioContextRef.current.close();
      if (playbackContextRef.current) playbackContextRef.current.close();
    };
  }, [isOpen, isMuted]);

  if (!isOpen) return null;

  return (
    <div className="voice-modal-backdrop">
      <div className="voice-modal-content">
        <button className="voice-modal-close" onClick={onClose}>
          <X size={20} />
        </button>

        <div className="voice-modal-header">
          <h2>Socratic Voice Space</h2>
          <p>Real-Time Bidirectional Dialogue</p>
        </div>

        {/* Pulse Animations and Mic States */}
        <div className="voice-visualizer-container">
          {status === 'connecting' && (
            <div className="voice-status-indicator connecting">
              <div className="pulse-circle" />
              <span>Connecting to Gemini Live...</span>
            </div>
          )}

          {status === 'listening' && (
            <div className="voice-status-indicator listening">
              <div className="pulse-circle active" />
              <div className="pulse-ring ring-1" />
              <div className="pulse-ring ring-2" />
              <span style={{ color: 'var(--color-happy)' }}>Listening to you... Go ahead and speak!</span>
            </div>
          )}

          {status === 'speaking' && (
            <div className="voice-status-indicator speaking">
              <div className="pulse-circle active speaking-pulse" />
              <div className="pulse-ring ring-1 speaking-ring" />
              <div className="pulse-ring ring-2 speaking-ring" />
              <span style={{ color: 'var(--secondary)' }}>Socratic Tutor is speaking...</span>
            </div>
          )}

          {status === 'error' && (
            <div className="voice-status-indicator error" style={{ gap: '0.8rem' }}>
              <AlertCircle size={40} color="var(--color-frustrated)" />
              <p style={{ color: 'var(--color-frustrated)', fontSize: '0.9rem', textAlign: 'center', maxWidth: '300px' }}>
                {errorMessage}
              </p>
            </div>
          )}
        </div>

        {/* Transcription Display */}
        {status === 'speaking' && transcript && (
          <div className="voice-transcript-box">
            <p>"{transcript}"</p>
          </div>
        )}

        {/* Control Buttons */}
        <div className="voice-modal-controls">
          <button 
            className={`voice-control-btn ${isMuted ? 'muted' : ''}`}
            onClick={() => setIsMuted(!isMuted)}
            disabled={status === 'error' || status === 'connecting'}
            title={isMuted ? "Unmute microphone" : "Mute microphone"}
          >
            {isMuted ? <MicOff size={22} /> : <Mic size={22} />}
            <span>{isMuted ? "Muted" : "Active"}</span>
          </button>
        </div>
      </div>
    </div>
  );
}