sc4/lib/core/dbpf-header.js

A command line utility for automating SimCity 4 modding tasks & modifying savegames

// # dbpf-header.js
import { SmartBuffer } from 'smart-arraybuffer';
import Version from './version.js';
// # Header
export default class Header {
    buffer;
    // ## constructor(opts)
    constructor(opts) {
        if (opts instanceof Uint8Array) {
            this.buffer = opts;
        }
        else {
            this.buffer = getDefaultHeader(opts);
        }
    }
    // ## get #reader()
    get #reader() {
        return SmartBuffer.fromBuffer(this.buffer);
    }
    get #writer() {
        return SmartBuffer.fromBuffer(this.buffer);
    }
    // ## get id()
    get id() {
        return this.#reader.readString(4);
    }
    // ## get version()
    get version() {
        const rs = this.#reader;
        const major = rs.readUInt32LE(4);
        const minor = rs.readUInt32LE(8);
        return [major, minor].join('.');
    }
    get created() { return new Date(1000 * this.#reader.readUInt32LE(24)); }
    set created(value) {
        this.#writer.writeUInt32LE(toUnixTimestamp(value), 24);
    }
    get modified() { return new Date(1000 * this.#reader.readUInt32LE(28)); }
    set modified(value) {
        this.#writer.writeUInt32LE(toUnixTimestamp(value), 28);
    }
    get indexMajor() { return this.#reader.readUInt32LE(32); }
    get indexMinor() { return this.#reader.readUInt32LE(60); }
    get indexCount() { return this.#reader.readUInt32LE(36); }
    get indexOffset() { return this.#reader.readUInt32LE(40); }
    get indexSize() { return this.#reader.readUInt32LE(44); }
    // ## toBuffer()
    toBuffer() { return this.buffer; }
    // ## toJSON()
    toJSON() {
        const { version, created, modified, indexMajor, indexMinor, indexCount, indexOffset, indexSize, } = this;
        return {
            version,
            created,
            modified,
            indexMajor,
            indexMinor,
            indexCount,
            indexOffset,
            indexSize,
        };
    }
    [Symbol.for('nodejs.util.inspect.custom')]() {
        return this.toJSON();
    }
}
// # getDefaultHeader(opts)
function getDefaultHeader(opts = {}) {
    const { version = '1.0', created = Date.now(), modified = Date.now(), indexMajor = 7, indexMinor = 0, indexCount = 0, indexOffset = 0, indexSize = 0, } = opts;
    const buffer = new SmartBuffer({ size: 96 });
    buffer.writeString('DBPF');
    const [major, minor] = new Version(version);
    buffer.writeUInt32LE(major);
    buffer.writeUInt32LE(minor);
    buffer.writeUInt32LE(toUnixTimestamp(created), 24);
    buffer.writeUInt32LE(toUnixTimestamp(modified), 28);
    buffer.writeUInt32LE(indexMajor, 32);
    buffer.writeUInt32LE(indexCount, 36);
    buffer.writeUInt32LE(indexOffset, 40);
    buffer.writeUInt32LE(indexSize, 44);
    buffer.writeUInt32LE(indexMinor, 60);
    return buffer.internalUint8Array;
}
// # toUnixTimestamp(date)
function toUnixTimestamp(date) {
    if (typeof date === 'number')
        return date / 1000;
    else if (typeof date === 'string')
        return Date.parse(date) / 1000;
    else
        return date.getTime() / 1000;
}