import type {BufferIterator} from '../../../iterator/buffer-iterator';

export interface AvccBox {
	type: 'avcc-box';
	privateData: Uint8Array;
	configurationString: string;
}

export const parseAvcc = ({
	data,
	size,
}: {
	data: BufferIterator;
	size: number;
}): AvccBox => {
	const confVersion = data.getUint8();
	if (confVersion !== 1) {
		throw new Error(`Unsupported AVCC version ${confVersion}`);
	}

	const profile = data.getUint8();
	const profileCompatibility = data.getUint8();
	const level = data.getUint8();

	const str = `${profile.toString(16).padStart(2, '0')}${profileCompatibility.toString(16).padStart(2, '0')}${level.toString(16).padStart(2, '0')}`;

	data.counter.decrement(4);

	const privateData = data.getSlice(size - 8);

	return {
		type: 'avcc-box',
		privateData,
		configurationString: str,
	};
};