| 1 | import { sleep } from "/js/sleep.js"; |
| 2 | import * as shortcuts from "/js/shortcuts.js"; |
| 3 | |
| 4 | class TtsService extends EventTarget { |
| 5 | constructor() { |
| 6 | super(); |
| 7 | this.providers = new Map(); |
| 8 | this.synth = window.speechSynthesis; |
| 9 | this.browserUtterance = null; |
| 10 | this.audioEl = null; |
| 11 | this.currentAudio = null; |
| 12 | this.audioContext = null; |
| 13 | this.userHasInteracted = false; |
| 14 | this.ttsStream = null; |
| 15 | this._isSpeaking = false; |
| 16 | |
| 17 | this.setupUserInteractionHandling(); |
| 18 | } |
| 19 | |
| 20 | registerProvider(id, provider) { |
| 21 | if (!id || !provider || typeof provider.synthesize !== "function") { |
| 22 | throw new Error("TTS providers must define an id and synthesize(text)."); |
| 23 | } |
| 24 | |
| 25 | this.providers.set(id, provider); |
| 26 | this.emitProvidersChange(); |
| 27 | |
| 28 | return () => this.unregisterProvider(id); |
| 29 | } |
| 30 | |
| 31 | unregisterProvider(id) { |
| 32 | if (!this.providers.has(id)) return; |
| 33 | |
| 34 | const activeProviderId = this.getActiveProviderId(); |
| 35 | this.providers.delete(id); |
| 36 | |
| 37 | if (activeProviderId === id) { |
| 38 | this.stop(); |
| 39 | } |
| 40 | |
| 41 | this.emitProvidersChange(); |
| 42 | } |
| 43 | |
| 44 | getActiveProviderId() { |
| 45 | const next = this.providers.keys().next(); |
| 46 | return next.done ? "" : String(next.value || ""); |
| 47 | } |
| 48 | |
| 49 | getActiveProvider() { |
| 50 | const providerId = this.getActiveProviderId(); |
| 51 | return providerId ? this.providers.get(providerId) || null : null; |
| 52 | } |
| 53 | |
| 54 | hasProvider() { |
| 55 | return !!this.getActiveProvider(); |
| 56 | } |
| 57 | |
| 58 | isSpeaking() { |
| 59 | return this._isSpeaking; |
| 60 | } |
| 61 | |
| 62 | getState() { |
| 63 | return { |
| 64 | activeProviderId: this.getActiveProviderId(), |
| 65 | isSpeaking: this.isSpeaking(), |
| 66 | userHasInteracted: this.userHasInteracted, |
| 67 | }; |
| 68 | } |
| 69 | |
| 70 | emitProvidersChange() { |
| 71 | this.dispatchEvent( |
| 72 | new CustomEvent("providerschange", { |
| 73 | detail: { |
| 74 | activeProviderId: this.getActiveProviderId(), |
| 75 | providerIds: Array.from(this.providers.keys()), |
| 76 | }, |
| 77 | }), |
| 78 | ); |
| 79 | this.emitStateChange(); |
| 80 | } |
| 81 | |
| 82 | emitStateChange() { |
| 83 | this.dispatchEvent( |
| 84 | new CustomEvent("statechange", { |
| 85 | detail: this.getState(), |
| 86 | }), |
| 87 | ); |
| 88 | } |
| 89 | |
| 90 | setSpeaking(value) { |
| 91 | const next = !!value; |
| 92 | if (this._isSpeaking === next) return; |
| 93 | this._isSpeaking = next; |
| 94 | this.emitStateChange(); |
| 95 | } |
| 96 | |
| 97 | setupUserInteractionHandling() { |
| 98 | const enableAudio = () => { |
| 99 | if (this.userHasInteracted) return; |
| 100 | |
| 101 | this.userHasInteracted = true; |
| 102 | try { |
| 103 | this.audioContext = new (window.AudioContext || |
| 104 | window.webkitAudioContext)(); |
| 105 | this.audioContext.resume(); |
| 106 | } catch (_error) { |
| 107 | // AudioContext is unavailable in some browsers/modes. |
| 108 | } |
| 109 | |
| 110 | this.emitStateChange(); |
| 111 | }; |
| 112 | |
| 113 | const events = ["click", "touchstart", "keydown", "mousedown"]; |
| 114 | events.forEach((eventName) => { |
| 115 | document.addEventListener(eventName, enableAudio, { |
| 116 | once: true, |
| 117 | passive: true, |
| 118 | }); |
| 119 | }); |
| 120 | } |
| 121 | |
| 122 | showAudioPermissionPrompt() { |
| 123 | shortcuts.frontendNotification({ |
| 124 | type: "info", |
| 125 | message: "Click anywhere to enable audio playback", |
| 126 | displayTime: 5000, |
| 127 | frontendOnly: true, |
| 128 | }); |
| 129 | } |
| 130 | |
| 131 | async speak(text) { |
| 132 | const id = Math.random(); |
| 133 | return await this.speakStream(id, text, true); |
| 134 | } |
| 135 | |
| 136 | async speakStream(id, text, finished = false) { |
| 137 | if ( |
| 138 | this.ttsStream && |
| 139 | this.ttsStream.id === id && |
| 140 | this.ttsStream.text === text && |
| 141 | this.ttsStream.finished === finished |
| 142 | ) { |
| 143 | return; |
| 144 | } |
| 145 | |
| 146 | if (!this.userHasInteracted) { |
| 147 | this.showAudioPermissionPrompt(); |
| 148 | return; |
| 149 | } |
| 150 | |
| 151 | if (!this.ttsStream || this.ttsStream.id !== id) { |
| 152 | this.ttsStream = { |
| 153 | id, |
| 154 | text, |
| 155 | finished, |
| 156 | running: false, |
| 157 | lastChunkIndex: -1, |
| 158 | stopped: false, |
| 159 | chunks: [], |
| 160 | }; |
| 161 | } else { |
| 162 | this.ttsStream.finished = finished; |
| 163 | this.ttsStream.text = text; |
| 164 | } |
| 165 | |
| 166 | const cleanText = this.cleanText(text); |
| 167 | if (!cleanText.trim()) return; |
| 168 | |
| 169 | this.ttsStream.chunks = this.chunkText(cleanText); |
| 170 | if (this.ttsStream.chunks.length === 0) return; |
| 171 | |
| 172 | if (this.ttsStream.running) return; |
| 173 | this.ttsStream.running = true; |
| 174 | |
| 175 | const terminator = () => |
| 176 | this.ttsStream?.id !== id || this.ttsStream?.stopped; |
| 177 | |
| 178 | while (true) { |
| 179 | if (terminator()) break; |
| 180 | |
| 181 | const nextIndex = this.ttsStream.lastChunkIndex + 1; |
| 182 | if (nextIndex >= this.ttsStream.chunks.length) { |
| 183 | if (this.ttsStream.finished) break; |
| 184 | await new Promise((resolve) => setTimeout(resolve, 50)); |
| 185 | continue; |
| 186 | } |
| 187 | |
| 188 | if ( |
| 189 | nextIndex === this.ttsStream.chunks.length - 1 && |
| 190 | !this.ttsStream.finished |
| 191 | ) { |
| 192 | await new Promise((resolve) => setTimeout(resolve, 50)); |
| 193 | continue; |
| 194 | } |
| 195 | |
| 196 | this.ttsStream.lastChunkIndex = nextIndex; |
| 197 | const chunk = this.ttsStream.chunks[nextIndex]; |
| 198 | await this.speakChunk(chunk, nextIndex > 0, terminator); |
| 199 | } |
| 200 | |
| 201 | this.ttsStream.running = false; |
| 202 | } |
| 203 | |
| 204 | async speakChunk(text, waitForPrevious = false, terminator = null) { |
| 205 | const provider = this.getActiveProvider(); |
| 206 | |
| 207 | if (provider) { |
| 208 | try { |
| 209 | return await this.speakWithProvider( |
| 210 | provider, |
| 211 | text, |
| 212 | waitForPrevious, |
| 213 | terminator, |
| 214 | ); |
| 215 | } catch (error) { |
| 216 | console.error("TTS provider failed, falling back to browser TTS", error); |
| 217 | } |
| 218 | } |
| 219 | |
| 220 | return await this.speakWithBrowser(text, waitForPrevious, terminator); |
| 221 | } |
| 222 | |
| 223 | async speakWithProvider(provider, text, waitForPrevious = false, terminator = null) { |
| 224 | const payload = await provider.synthesize(text, { |
| 225 | providerId: this.getActiveProviderId(), |
| 226 | }); |
| 227 | |
| 228 | while (waitForPrevious && this.isSpeaking()) { |
| 229 | await sleep(25); |
| 230 | } |
| 231 | if (terminator && terminator()) return; |
| 232 | |
| 233 | if (!waitForPrevious) { |
| 234 | this.stopAudio(); |
| 235 | } |
| 236 | |
| 237 | if (!payload) return; |
| 238 | |
| 239 | if (Array.isArray(payload.audioParts)) { |
| 240 | for (const part of payload.audioParts) { |
| 241 | if (terminator && terminator()) return; |
| 242 | await this.playAudioBase64(part, payload.mimeType); |
| 243 | await sleep(100); |
| 244 | } |
| 245 | return; |
| 246 | } |
| 247 | |
| 248 | const audioBase64 = payload.audioBase64 || payload.audio; |
| 249 | if (audioBase64) { |
| 250 | await this.playAudioBase64(audioBase64, payload.mimeType); |
| 251 | } |
| 252 | } |
| 253 | |
| 254 | async speakWithBrowser(text, waitForPrevious = false, terminator = null) { |
| 255 | while (waitForPrevious && this.isSpeaking()) { |
| 256 | await sleep(25); |
| 257 | } |
| 258 | if (terminator && terminator()) return; |
| 259 | |
| 260 | if (!waitForPrevious) { |
| 261 | this.stopAudio(); |
| 262 | } |
| 263 | |
| 264 | return await new Promise((resolve, reject) => { |
| 265 | const utterance = new SpeechSynthesisUtterance(text); |
| 266 | this.browserUtterance = utterance; |
| 267 | |
| 268 | utterance.onstart = () => { |
| 269 | this.setSpeaking(true); |
| 270 | }; |
| 271 | utterance.onend = () => { |
| 272 | if (this.browserUtterance === utterance) { |
| 273 | this.browserUtterance = null; |
| 274 | } |
| 275 | this.setSpeaking(false); |
| 276 | resolve(); |
| 277 | }; |
| 278 | utterance.onerror = (error) => { |
| 279 | if (this.browserUtterance === utterance) { |
| 280 | this.browserUtterance = null; |
| 281 | } |
| 282 | this.setSpeaking(false); |
| 283 | reject(error); |
| 284 | }; |
| 285 | |
| 286 | this.synth.speak(utterance); |
| 287 | }); |
| 288 | } |
| 289 | |
| 290 | async playAudioBase64(base64Audio, mimeType = "audio/wav") { |
| 291 | return await new Promise((resolve, reject) => { |
| 292 | const audio = this.audioEl ? this.audioEl : (this.audioEl = new Audio()); |
| 293 | |
| 294 | audio.pause(); |
| 295 | audio.currentTime = 0; |
| 296 | |
| 297 | audio.onplay = () => { |
| 298 | this.setSpeaking(true); |
| 299 | }; |
| 300 | audio.onended = () => { |
| 301 | this.setSpeaking(false); |
| 302 | this.currentAudio = null; |
| 303 | resolve(); |
| 304 | }; |
| 305 | audio.onerror = (error) => { |
| 306 | this.setSpeaking(false); |
| 307 | this.currentAudio = null; |
| 308 | reject(error); |
| 309 | }; |
| 310 | |
| 311 | audio.src = `data:${mimeType};base64,${base64Audio}`; |
| 312 | this.currentAudio = audio; |
| 313 | |
| 314 | audio.play().catch((error) => { |
| 315 | this.setSpeaking(false); |
| 316 | this.currentAudio = null; |
| 317 | if (error?.name === "NotAllowedError") { |
| 318 | this.showAudioPermissionPrompt(); |
| 319 | this.userHasInteracted = false; |
| 320 | this.emitStateChange(); |
| 321 | } |
| 322 | reject(error); |
| 323 | }); |
| 324 | }); |
| 325 | } |
| 326 | |
| 327 | stop() { |
| 328 | this.stopAudio(); |
| 329 | if (this.ttsStream) { |
| 330 | this.ttsStream.stopped = true; |
| 331 | } |
| 332 | |
| 333 | const provider = this.getActiveProvider(); |
| 334 | try { |
| 335 | provider?.stop?.(); |
| 336 | } catch (error) { |
| 337 | console.error("Failed to stop TTS provider cleanly", error); |
| 338 | } |
| 339 | } |
| 340 | |
| 341 | stopAudio() { |
| 342 | if (this.synth?.speaking) { |
| 343 | this.synth.cancel(); |
| 344 | } |
| 345 | |
| 346 | if (this.audioEl) { |
| 347 | this.audioEl.pause(); |
| 348 | this.audioEl.currentTime = 0; |
| 349 | } |
| 350 | |
| 351 | this.currentAudio = null; |
| 352 | this.setSpeaking(false); |
| 353 | } |
| 354 | |
| 355 | chunkText(text, { maxChunkLength = 135, lineSeparator = "..." } = {}) { |
| 356 | const INC_LIMIT = maxChunkLength * 2; |
| 357 | const MIN_CHUNK_LENGTH = 20; |
| 358 | |
| 359 | const splitDeep = (segment) => { |
| 360 | if (segment.length <= INC_LIMIT) return [segment]; |
| 361 | const byComma = segment.match(/[^,]+(?:,|$)/g); |
| 362 | if (byComma.length > 1) { |
| 363 | return byComma.flatMap((part, index) => |
| 364 | splitDeep( |
| 365 | index < byComma.length - 1 ? part : part.replace(/,$/, ""), |
| 366 | ), |
| 367 | ); |
| 368 | } |
| 369 | |
| 370 | const out = []; |
| 371 | let part = ""; |
| 372 | for (const word of segment.split(/\s+/)) { |
| 373 | const need = part ? part.length + 1 + word.length : word.length; |
| 374 | if (need <= maxChunkLength) { |
| 375 | part += (part ? " " : "") + word; |
| 376 | } else { |
| 377 | if (part) out.push(part); |
| 378 | if (word.length > maxChunkLength) { |
| 379 | for (let index = 0; index < word.length; index += maxChunkLength) { |
| 380 | out.push(word.slice(index, index + maxChunkLength)); |
| 381 | } |
| 382 | part = ""; |
| 383 | } else { |
| 384 | part = word; |
| 385 | } |
| 386 | } |
| 387 | } |
| 388 | if (part) out.push(part); |
| 389 | return out; |
| 390 | }; |
| 391 | |
| 392 | const sentenceTokens = (line) => { |
| 393 | const tokens = []; |
| 394 | let start = 0; |
| 395 | for (let index = 0; index < line.length; index++) { |
| 396 | const character = line[index]; |
| 397 | if ( |
| 398 | (character === "." || character === "!" || character === "?") && |
| 399 | /\s/.test(line[index + 1] || "") |
| 400 | ) { |
| 401 | tokens.push(line.slice(start, index + 1)); |
| 402 | index += 1; |
| 403 | start = index + 1; |
| 404 | } |
| 405 | } |
| 406 | if (start < line.length) { |
| 407 | tokens.push(line.slice(start)); |
| 408 | } |
| 409 | return tokens.flatMap((token) => splitDeep(token.trim())).filter(Boolean); |
| 410 | }; |
| 411 | |
| 412 | const initialChunks = []; |
| 413 | const lines = text.split(/\n+/).filter((line) => line.trim()); |
| 414 | for (const line of lines) { |
| 415 | initialChunks.push(...sentenceTokens(line.trim())); |
| 416 | } |
| 417 | |
| 418 | const finalChunks = []; |
| 419 | let currentChunk = ""; |
| 420 | |
| 421 | for (let index = 0; index < initialChunks.length; index++) { |
| 422 | const chunk = initialChunks[index]; |
| 423 | if (!currentChunk) { |
| 424 | currentChunk = chunk; |
| 425 | if ( |
| 426 | index === initialChunks.length - 1 || |
| 427 | currentChunk.length >= MIN_CHUNK_LENGTH |
| 428 | ) { |
| 429 | finalChunks.push(currentChunk); |
| 430 | currentChunk = ""; |
| 431 | } |
| 432 | continue; |
| 433 | } |
| 434 | |
| 435 | if (currentChunk.length < MIN_CHUNK_LENGTH) { |
| 436 | const merged = `${currentChunk} ${lineSeparator} ${chunk}`; |
| 437 | if (merged.length <= maxChunkLength) { |
| 438 | currentChunk = merged; |
| 439 | } else { |
| 440 | finalChunks.push(currentChunk); |
| 441 | currentChunk = chunk; |
| 442 | } |
| 443 | } else { |
| 444 | finalChunks.push(currentChunk); |
| 445 | currentChunk = chunk; |
| 446 | } |
| 447 | |
| 448 | if (index === initialChunks.length - 1 && currentChunk) { |
| 449 | finalChunks.push(currentChunk); |
| 450 | } |
| 451 | } |
| 452 | |
| 453 | return finalChunks.map((chunk) => chunk.trimEnd()); |
| 454 | } |
| 455 | |
| 456 | cleanText(text) { |
| 457 | const SUB = "\x1A"; |
| 458 | const codePlaceholder = `${SUB}code${SUB}`; |
| 459 | const tablePlaceholder = `${SUB}table${SUB}`; |
| 460 | |
| 461 | text = text.replace( |
| 462 | /```(?:[a-zA-Z0-9]*\n)?[\s\S]*?```/g, |
| 463 | codePlaceholder, |
| 464 | ); |
| 465 | text = text.replace(/```(?:[a-zA-Z0-9]*\n)?[\s\S]*$/g, codePlaceholder); |
| 466 | text = text.replace(/`([^`]*)`/g, "$1"); |
| 467 | |
| 468 | try { |
| 469 | const parser = new DOMParser(); |
| 470 | const doc = parser.parseFromString(`<div>${text}</div>`, "text/html"); |
| 471 | doc.querySelectorAll("pre, code").forEach((element) => { |
| 472 | element.textContent = codePlaceholder; |
| 473 | }); |
| 474 | text = doc.body.textContent || ""; |
| 475 | } catch (_error) { |
| 476 | text = text.replace(/<pre[^>]*>[\s\S]*?<\/pre>/gi, codePlaceholder); |
| 477 | text = text.replace(/<code[^>]*>[\s\S]*?<\/code>/gi, codePlaceholder); |
| 478 | text = text.replace(/<[^>]+>/g, ""); |
| 479 | } |
| 480 | |
| 481 | text = text.replace(/\[([^\]]+)\]\([^)]+\)/g, "$1"); |
| 482 | text = text.replace(/[*_#]+/g, ""); |
| 483 | |
| 484 | if (text.includes("|")) { |
| 485 | const tableLines = text |
| 486 | .split("\n") |
| 487 | .filter((line) => line.includes("|") && line.trim().startsWith("|")); |
| 488 | if (tableLines.length > 0) { |
| 489 | for (const line of tableLines) { |
| 490 | text = text.replace(line, tablePlaceholder); |
| 491 | } |
| 492 | } else { |
| 493 | text = text.replace(/\|[^\n]*\|/g, tablePlaceholder); |
| 494 | } |
| 495 | } |
| 496 | |
| 497 | text = text.replace( |
| 498 | /([\u2700-\u27BF]|[\uE000-\uF8FF]|\uD83C[\uDC00-\uDFFF]|\uD83D[\uDC00-\uDFFF]|[\u2011-\u26FF]|\uD83E[\uDD10-\uDDFF])/g, |
| 499 | "", |
| 500 | ); |
| 501 | |
| 502 | text = text.replace(/https?:\/\/[^\s]+/g, (match) => { |
| 503 | try { |
| 504 | return new URL(match).hostname; |
| 505 | } catch { |
| 506 | return ""; |
| 507 | } |
| 508 | }); |
| 509 | |
| 510 | text = text.replace( |
| 511 | /[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}/g, |
| 512 | "UUID", |
| 513 | ); |
| 514 | text = text.replace(/[ \t]+/g, " "); |
| 515 | |
| 516 | const mergePlaceholders = (value, placeholder, replacement) => { |
| 517 | const pattern = new RegExp(`${placeholder}\\s*${placeholder}`, "g"); |
| 518 | while (pattern.test(value)) { |
| 519 | value = value.replace(pattern, placeholder); |
| 520 | } |
| 521 | return value.replace(new RegExp(placeholder, "g"), replacement); |
| 522 | }; |
| 523 | |
| 524 | text = mergePlaceholders(text, codePlaceholder, "See code attached ..."); |
| 525 | text = mergePlaceholders(text, tablePlaceholder, "See table attached ..."); |
| 526 | |
| 527 | return text.trim(); |
| 528 | } |
| 529 | } |
| 530 | |
| 531 | export const ttsService = new TtsService(); |
| 532 | globalThis.ttsService = ttsService; |