osrscachereader/src/cacheReader/cacheTypes/Index.js

Read Old-School Runescape Cache files

import Archive from "./Archive.js";
import File from "./File.js";

/**
 * An index from the cache
 * @category Cache Types
 * @hideconstructor
 */
class Index {
    constructor(id) {
        /**
         * The ID of this Index
         * @type {number}
         */
        this.id = id;

        /** @type {number} */
        this.protocol = 0;

        /** @type {number} */
        this.revision = -1;

        /** @type {number} */
        this.flags = 0;

        /** @type {number} */
        this.crc = 0;

        /** @type {boolean} */
        this.sized = false;

        /** @type {boolean} */
        this.named = false;

        /**
         * Total amount of archives
         * @type {number}
         */
        this.archivesCount = 0;

        /**
         * Dictionary containing archives. Key is the ID of the archive.
         * @type {Object}
         */
        this.archives = {};

        /**
         * Used for loading files for archives
         * @type {Array}
         */
        this.indexSegments = [];
    }

    loadIndexData(data) {
        let dataview = new DataView(data.buffer);

        this.protocol = dataview.readUint8();

        if (this.protocol >= 6) {
            this.revision = dataview.readInt32();
        }
        this.flags = dataview.readUint8();

        this.named = (1 & this.flags) != 0;
        this.sized = (4 & this.flags) != 0;

        if (this.protocol >= 7) {
            this.archivesCount = dataview.readBigSmart();
        } else {
            this.archivesCount = dataview.readUint16();
        }

        let lastArchiveId = 0;
        for (let i = 0; i < this.archivesCount; i++) {
            let archiveId;
            if (this.protocol >= 7) {
                archiveId = lastArchiveId += dataview.readBigSmart();
            } else {
                archiveId = lastArchiveId += dataview.readInt16();
            }

            this.archives[archiveId] = new Archive();
            this.archives[archiveId].id = archiveId;
        }

        let archiveKeys = Object.keys(this.archives);

        if (this.named) {
            for (let i = 0; i < this.archivesCount; i++) {
                let nameHash = dataview.readInt32();
                this.archives[archiveKeys[i]].nameHash = nameHash;
            }
        }

        for (let i = 0; i < this.archivesCount; i++) {
            let crc = dataview.readInt32();
            this.archives[archiveKeys[i]].crc = crc;
        }

        if (this.sized) {
            for (let i = 0; i < this.archivesCount; i++) {
                this.archives[archiveKeys[i]].compressedSize = dataview.readInt32();
                this.archives[archiveKeys[i]].decompressedSize = dataview.readInt32();
            }
        }

        for (let i = 0; i < this.archivesCount; i++) {
            let revision = dataview.readInt32();
            this.archives[archiveKeys[i]].revision = revision;
        }

        for (let i = 0; i < this.archivesCount; i++) {
            let numberOfFiles;
            if (this.protocol >= 7) {
                numberOfFiles = dataview.readBigSmart();
            } else {
                numberOfFiles = dataview.readUint16();
            }
            if (numberOfFiles <= 0)
                console.log("Warning: Files <= 0 for archive " + i + ". Files amount: " + numberOfFiles);
            this.archives[archiveKeys[i]].files = Array(numberOfFiles).fill(undefined);
        }

        for (let i = 0; i < this.archivesCount; i++) {
            let fileID = 0;
            for (let j = 0; j < this.archives[archiveKeys[i]].files.length; j++) {
                if (this.protocol >= 7) {
                    fileID += dataview.readBigSmart();
                } else {
                    fileID += dataview.readUint16();
                }
                this.archives[archiveKeys[i]].files[j] = new File(fileID);
            }
        }

        if (this.named) {
            for (let i = 0; i < this.archivesCount; i++) {
                for (let j = 0; j < this.archives[archiveKeys[i]].files.length; j++) {
                    let fileName = dataview.readUint32();
                    if (fileName == 0) {
                        fileName = this.archives[archiveKeys[i]].nameHash;
                    }
                    this.archives[archiveKeys[i]].files[j].nameHash = fileName;
                }
            }
        }
    }

    /**
     * Get an Archive from this Index
     * @param {Number} archive A number or can be a ConfigType if the IndexType is CONFIGS
     * @returns [Archive]{@link Archive}
     */
    getArchive(archive) {
        let archiveId;
        if (archive.constructor.name === "Object") {
            archiveId = archive.id;
        } else if (!isNaN(archive)) {
            archiveId = Number(archive);
        }

        archive = this.archives[archiveId];
        if (archive == undefined) {
            throw "Archive " + archiveId + " does not exist";
        }

        return archive;
    }

    toString() {
        return this.id;
    }
}

export default Index;