Global TTS interrupt suppression (its being a bitch)

package.json

@@ -1,6 +1,6 @@
 {
 	"name": "@ztimson/utils",
-	"version": "0.28.8",
+	"version": "0.28.12",
 	"description": "Utility library",
 	"author": "Zak Timson",
 	"license": "MIT",

src/index.ts

@@ -21,5 +21,6 @@ export * from './search';
 export * from './string';
 export * from './template';
 export * from './time';
+export * from './tts';
 export * from './types';
 export * from 'var-persist';

src/string.ts

@@ -140,7 +140,7 @@ export function pascalCase(str?: string): string {
  * @param {string} str Input string with emojis
  * @returns {string} Sanitized string without emojis
  */
-function removeEmojis(str: string): string {
+export function removeEmojis(str: string): string {
 	const emojiRegex = /(?:[\u2700-\u27bf]|(?:\ud83c[\udde6-\uddff]){2}|[\ud83c[\udde6-\uddff]|[\ud83d[\ude00-\ude4f]|[\ud83d[\ude80-\udeff]|[\ud83c[\udd00-\uddff]|[\ud83d[\ude50-\ude7f]|[\u2600-\u26ff]|[\u2700-\u27bf]|[\ud83e[\udd00-\uddff]|[\ud83c[\udf00-\uffff]|[\ud83d[\ude00-\udeff]|[\ud83c[\udde6-\uddff])/g;
 	return str.replace(emojiRegex, '');
 }

src/tts.ts

@@ -0,0 +1,148 @@
+import {removeEmojis} from './string.ts';
+
+export class TTS {
+	private static readonly QUALITY_PATTERNS = ['Google', 'Microsoft', 'Samantha', 'Premium', 'Natural', 'Neural'];
+	private static _errorHandlerInstalled = false;
+
+	private _currentUtterance: SpeechSynthesisUtterance | null = null;
+	private _voicesLoaded: Promise<void>;
+	private _stoppedUtterances = new WeakSet<SpeechSynthesisUtterance>();
+
+	private _rate: number = 1.0;
+	get rate(): number { return this._rate; }
+	set rate(value: number) {
+		this._rate = value;
+		if(this._currentUtterance) this._currentUtterance.rate = value;
+	}
+
+	private _pitch: number = 1.0;
+	get pitch(): number { return this._pitch; }
+	set pitch(value: number) {
+		this._pitch = value;
+		if(this._currentUtterance) this._currentUtterance.pitch = value;
+	}
+
+	private _volume: number = 1.0;
+	get volume(): number { return this._volume; }
+	set volume(value: number) {
+		this._volume = value;
+		if(this._currentUtterance) this._currentUtterance.volume = value;
+	}
+
+	private _voice: SpeechSynthesisVoice | undefined;
+	get voice(): SpeechSynthesisVoice | undefined { return this._voice; }
+	set voice(value: SpeechSynthesisVoice | undefined) {
+		this._voice = value;
+		if(this._currentUtterance && value) this._currentUtterance.voice = value;
+	}
+
+	constructor(config?: {rate?: number; pitch?: number; volume?: number; voice?: SpeechSynthesisVoice | null}) {
+		TTS.installErrorHandler();
+		this._voicesLoaded = this.initializeVoices();
+		if(config) {
+			if(config.rate !== undefined) this._rate = config.rate;
+			if(config.pitch !== undefined) this._pitch = config.pitch;
+			if(config.volume !== undefined) this._volume = config.volume;
+			this._voice = config.voice === null ? undefined : (config.voice || undefined);
+		}
+	}
+
+	private static installErrorHandler(): void {
+		if(this._errorHandlerInstalled) return;
+		window.addEventListener('unhandledrejection', (event) => {
+			if(event.reason?.error === 'interrupted' && event.reason instanceof SpeechSynthesisErrorEvent) event.preventDefault();
+		});
+		this._errorHandlerInstalled = true;
+	}
+
+	private initializeVoices(): Promise<void> {
+		return new Promise((resolve) => {
+			const voices = window.speechSynthesis.getVoices();
+			if(voices.length > 0) {
+				if(!this._voice) this._voice = TTS.bestVoice();
+				resolve();
+			} else {
+				const handler = () => {
+					window.speechSynthesis.removeEventListener('voiceschanged', handler);
+					if(!this._voice) this._voice = TTS.bestVoice();
+					resolve();
+				};
+				window.speechSynthesis.addEventListener('voiceschanged', handler);
+			}
+		});
+	}
+
+	private static bestVoice(lang = 'en'): SpeechSynthesisVoice | undefined {
+		const voices = window.speechSynthesis.getVoices();
+		for (const pattern of this.QUALITY_PATTERNS) {
+			const voice = voices.find(v => v.name.includes(pattern) && v.lang.startsWith(lang));
+			if(voice) return voice;
+		}
+		return voices.find(v => v.lang.startsWith(lang));
+	}
+
+	private static cleanText(text: string): string {
+		return removeEmojis(text)
+			.replace(/```[\s\S]*?```/g, ' code block ')
+			.replace(/[#*_~`]/g, '');
+	}
+
+	private createUtterance(text: string): SpeechSynthesisUtterance {
+		const cleanedText = TTS.cleanText(text);
+		const utterance = new SpeechSynthesisUtterance(cleanedText);
+		const voice = this._voice || TTS.bestVoice();
+		if(voice) utterance.voice = voice;
+		utterance.rate = this._rate;
+		utterance.pitch = this._pitch;
+		utterance.volume = this._volume;
+		return utterance;
+	}
+
+	async speak(text: string): Promise<void> {
+		if(!text.trim()) return Promise.resolve();
+		await this._voicesLoaded;
+		return new Promise((resolve, reject) => {
+			this._currentUtterance = this.createUtterance(text);
+			const utterance = this._currentUtterance;
+			utterance.onend = () => {
+				this._currentUtterance = null;
+				resolve();
+			};
+			utterance.onerror = (error) => {
+				this._currentUtterance = null;
+				if(this._stoppedUtterances.has(utterance) && error.error === 'interrupted') resolve();
+				else reject(error);
+			};
+			window.speechSynthesis.speak(utterance);
+		});
+	}
+
+	stop(): void {
+		if(this._currentUtterance) this._stoppedUtterances.add(this._currentUtterance);
+		window.speechSynthesis.cancel();
+		this._currentUtterance = null;
+	}
+
+	speakStream(): {next: (text: string) => void, done: () => Promise<void>} {
+		let buffer = '';
+		let streamPromise: Promise<void> = Promise.resolve();
+		const sentenceRegex = /[^.!?\n]+[.!?\n]+/g;
+		return {
+			next: (text: string): void => {
+				buffer += text;
+				const sentences = buffer.match(sentenceRegex);
+				if(sentences) {
+					sentences.forEach(sentence => streamPromise = this.speak(sentence.trim()));
+					buffer = buffer.replace(sentenceRegex, '');
+				}
+			},
+			done: async (): Promise<void> => {
+				if(buffer.trim()) {
+					streamPromise = this.speak(buffer.trim());
+					buffer = '';
+				}
+				await streamPromise;
+			}
+		};
+	}
+}