File size: 6,117 Bytes
b8cc2bf
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
/**
 * BufferWorkerClient
 *
 * Main-thread API for the centralized BufferWorker.
 * Provides promise-based reads and fire-and-forget writes.
 */

import type {
    LayerId,
    BufferWorkerConfig,
    BufferWorkerResponse,
    HasSpeechResult,
    RangeResult,
    BufferState,
} from './types';

export class BufferWorkerClient {
    private worker: Worker;
    private messageId = 0;
    private pendingPromises = new Map<number, { resolve: (v: any) => void; reject: (e: any) => void }>();
    private ready = false;

    constructor() {
        this.worker = new Worker(new URL('./buffer.worker.ts', import.meta.url), {
            type: 'module',
        });
        this.worker.onmessage = (e: MessageEvent<BufferWorkerResponse>) => {
            this.handleMessage(e.data);
        };
        this.worker.onerror = (e: Event) => {
            const err = e as ErrorEvent;
            console.error('[BufferWorkerClient] Worker error:', err.message);
            for (const [, p] of this.pendingPromises) {
                p.reject(new Error(err.message || 'BufferWorker error'));
            }
            this.pendingPromises.clear();
        };
    }

    // ---- Lifecycle ----

    async init(config: BufferWorkerConfig): Promise<void> {
        await this.sendRequest('INIT', config);
        this.ready = true;
    }

    async reset(): Promise<void> {
        await this.sendRequest('RESET', undefined);
    }

    dispose(): void {
        this.worker.terminate();
        for (const [, p] of this.pendingPromises) {
            p.reject(new Error('BufferWorkerClient disposed'));
        }
        this.pendingPromises.clear();
        this.ready = false;
    }

    // ---- Producers (fire-and-forget for low latency) ----

    /**
     * Write a single scalar value to a VAD layer (energyVad or inferenceVad).
     * Fire-and-forget for minimal latency.
     */
    writeScalar(layer: LayerId, value: number): void {
        if (!this.ready) return;
        this.worker.postMessage({
            type: 'WRITE',
            payload: { layer, data: [value] },
        });
    }

    /**
     * Write a multi-dimensional entry (e.g., mel spectrogram frame).
     * Transfers the buffer for zero-copy.
     */
    writeEntry(layer: LayerId, data: Float32Array): void {
        if (!this.ready) return;
        const copy = new Float32Array(data);
        this.worker.postMessage(
            { type: 'WRITE', payload: { layer, data: copy } },
            [copy.buffer]
        );
    }

    /**
     * Write a batch of entries to a layer. Transfers the buffer.
     */
    writeBatch(layer: LayerId, data: Float32Array, globalSampleOffset?: number): void {
        if (!this.ready) return;
        const copy = new Float32Array(data);
        this.worker.postMessage(
            { type: 'WRITE_BATCH', payload: { layer, data: copy, globalSampleOffset } },
            [copy.buffer]
        );
    }

    /**
     * Write a batch of entries to a layer by transferring ownership of the buffer.
     * The caller must not reuse `data` after calling this.
     */
    writeBatchTransfer(layer: LayerId, data: Float32Array, globalSampleOffset?: number): void {
        if (!this.ready) return;
        this.worker.postMessage(
            { type: 'WRITE_BATCH', payload: { layer, data, globalSampleOffset } },
            [data.buffer]
        );
    }

    /**
     * Write raw audio samples. Fire-and-forget with buffer transfer.
     */
    writeAudio(samples: Float32Array): void {
        if (!this.ready) return;
        const copy = new Float32Array(samples);
        this.worker.postMessage(
            { type: 'WRITE_BATCH', payload: { layer: 'audio' as LayerId, data: copy } },
            [copy.buffer]
        );
    }

    // ---- Consumers (async queries) ----

    /**
     * Check if any VAD entry exceeds a threshold in a sample range.
     * Used by v4Tick to decide whether to trigger transcription.
     */
    async hasSpeech(
        layer: 'energyVad' | 'inferenceVad',
        startSample: number,
        endSample: number,
        threshold: number,
    ): Promise<HasSpeechResult> {
        return this.sendRequest('HAS_SPEECH', { layer, startSample, endSample, threshold });
    }

    /**
     * Get the duration of trailing silence from the write head.
     * Scans backward in the specified VAD layer until a probability >= threshold is found.
     */
    async getSilenceTailDuration(
        layer: 'energyVad' | 'inferenceVad',
        threshold: number,
    ): Promise<number> {
        const result = await this.sendRequest('GET_SILENCE_TAIL', { layer, threshold });
        return result.durationSec;
    }

    /**
     * Query data for an arbitrary sample range across multiple layers.
     * Returns correlated slices from each requested layer.
     */
    async queryRange(
        startSample: number,
        endSample: number,
        layerIds: LayerId[],
    ): Promise<RangeResult> {
        return this.sendRequest('QUERY_RANGE', { startSample, endSample, layers: layerIds });
    }

    /**
     * Get a snapshot of the buffer state for debugging / UI.
     */
    async getState(): Promise<BufferState> {
        return this.sendRequest('GET_STATE', undefined);
    }

    // ---- Internal ----

    private handleMessage(msg: BufferWorkerResponse): void {
        if (msg.type === 'ERROR') {
            const p = this.pendingPromises.get(msg.id);
            if (p) {
                this.pendingPromises.delete(msg.id);
                p.reject(new Error(msg.payload));
            }
            return;
        }

        if (msg.id !== undefined) {
            const p = this.pendingPromises.get(msg.id);
            if (p) {
                this.pendingPromises.delete(msg.id);
                p.resolve(msg.payload);
            }
        }
    }

    private sendRequest(type: string, payload: any): Promise<any> {
        return new Promise((resolve, reject) => {
            const id = ++this.messageId;
            this.pendingPromises.set(id, { resolve, reject });
            this.worker.postMessage({ type, payload, id });
        });
    }
}