@echogarden/gnuspeech-wasm/src/utilities/Utf8.ts

WebAssembly port of the GnuSpeech speech synthesizer.

export function encodeUtf8(text: string) {
	const textEncoder = new TextEncoder()

	return textEncoder.encode(text)
}

export function decodeUtf8(encodedString: Uint8Array) {
	const maxChunkLength = 2 ** 24

	const decoder = new ChunkedUtf8Decoder()

	for (let offset = 0; offset < encodedString.length; offset += maxChunkLength) {
		const chunk = encodedString.subarray(offset, offset + maxChunkLength)

		decoder.writeChunk(chunk)
	}

	return decoder.toString()
}

export class ChunkedUtf8Decoder {
	private str = ''
	private readonly textDecoder = new TextDecoder('utf-8')

	writeChunk(chunk: Uint8Array) {
		const decodedChunk = this.textDecoder.decode(chunk)

		this.str += decodedChunk
	}

	toString() {
		return this.str
	}
}