libraries.ts

import { Resource } from '../load';
import { bits } from '../../utils';

const parseLibrary = (resource: Resource, index: number) => {
    const buffer = resource.getEntry(resource.first + index);
    const dataView = new DataView(buffer);
    const numLayouts = dataView.getUint32(0, true) / 4;
    const layouts = [];
    for (let i = 0; i < numLayouts; i += 1) {
        const offset = dataView.getUint32(i * 4, true);
        const nextOffset = i === numLayouts - 1 ?
            dataView.byteLength
            : dataView.getUint32((i + 1) * 4, true);
        const layoutDataView = new DataView(buffer, offset, nextOffset - offset);
        layouts.push(parseLayout(layoutDataView, i, resource.type === 'BL1'));
    }
    return layouts;
};

const parseLayout = (dataView: DataView, index: number, isLBA1: boolean) => {
    const nX = dataView.getUint8(0);
    const nY = dataView.getUint8(1);
    const nZ = dataView.getUint8(2);
    const numBricks = nX * nY * nZ;
    const blocks = [];
    const offset = 3;
    for (let i = 0; i < numBricks; i += 1) {
        const type = dataView.getUint8(offset + (i * 4) + 1);
        const shape = dataView.getUint8(offset + (i * 4));
        const brick = dataView.getUint16(offset + (i * 4) + 2, true);
        blocks.push({
            shape,
            sound: bits(type, 0, 4),
            // sound 2 only exist in LBA1
            // for LBA1 each sound maps each step in the animation state (left or right)
            // note, these are not the sample index, instead is just a list of sound types
            sound2: isLBA1 ? bits(type, 4, 4) : -1,
            // only water (1) exist as groupType in LBA1
            groundType: isLBA1 ? (type & 0xFF) === 0xF1 ? 1 : 0 : bits(type, 4, 4),
            brick,
        });
    }
    return {
        index,
        nX,
        nY,
        nZ,
        blocks
    };
};

export { parseLibrary };