type TypedArray = Float32Array | Int32Array | Uint32Array | Uint16Array;

/** Packed buffer storing multiple vertex attributes in interleaved layout. */
export class InterleavedBuffer {
	#array: TypedArray;
	#stride: number;

	needsUpdate = false;

	updateRange: { offset: number; count: number } = { offset: 0, count: -1 };

	constructor(array: TypedArray, stride: number) {
		this.#array = array;
		this.#stride = stride;
	}

	get array(): TypedArray {
		return this.#array;
	}

	get stride(): number {
		return this.#stride;
	}

	get count(): number {
		return this.#array.length / this.#stride;
	}

	clone(): InterleavedBuffer {
		return new InterleavedBuffer(this.#array.slice(), this.#stride);
	}

	copy(source: InterleavedBuffer): this {
		this.#array.set(source.array);
		return this;
	}

	set(value: ArrayLike<number>, offset: number): this {
		this.#array.set(value, offset);
		return this;
	}

	getX(index: number): number {
		return this.#array[index * this.#stride];
	}

	getY(index: number): number {
		return this.#array[index * this.#stride + 1];
	}

	getZ(index: number): number {
		return this.#array[index * this.#stride + 2];
	}

	getW(index: number): number {
		return this.#array[index * this.#stride + 3];
	}
}