import { SFZone, Shdr, SF2File } from "./index.js";
//@ts-ignore
export class SampleData {
	uint8s: Uint8Array;
	floatArr: SharedArrayBuffer;

	constructor(rawData: Uint8Array) {
		this.uint8s = rawData;
		this.floatArr = new SharedArrayBuffer(rawData.byteLength * 2);
		const dv2 = new DataView(this.floatArr);
		const dv = new DataView(this.uint8s.buffer);
		for (let i = 0; i < dv.byteLength / 2 - 1; i++) {
			dv2.setFloat32(i * 4, dv.getInt16(2 * i, true) / 0x7fff, true);
		}
	}

	sampleBuffer({ start, end, startLoop, endLoop }: Shdr, pitchRatio = 1, length = 48000 * 3) {
		const data = new Float32Array(this.floatArr);
		const loop = [startLoop - start, endLoop - start];

		function* shift() {
			let pos = 0x00;
			let n = 0;
			let shift = 0.0;
			while (n++ < length) {
				//@ts-ignore
				yield lerp(data[pos], data[pos + 1], shift);
				shift = shift + pitchRatio;
				while (shift >= 1) {
					shift--;
					pos++;
				}
				if (pos >= loop[1]) pos = loop[0];
				yield data[pos];
			}
			return data[pos];
		}
		return shift();
	}
}