@abextm/cache2/dist/Reader.js

Utilities for reading OSRS "caches"

import { CacheVersion } from "./Cache.js";
import { Params } from "./types.js";
export const cp1252CharMap = (() => {
    const ext = "€?‚ƒ„…†‡ˆ‰Š‹Œ?Ž??‘’“”•–—˜™š›œ?žŸ";
    let out = new Array(256);
    for (let i = 0; i < out.length; i++) {
        let v;
        let ei = i - 128;
        if (ei > 0 && ei < ext.length) {
            v = ext.charAt(ei);
        }
        else {
            v = String.fromCodePoint(i);
        }
        out[i] = v;
    }
    return out;
})();
export class Reader {
    version;
    view;
    offset = 0;
    get length() {
        return this.view.byteLength;
    }
    get remaining() {
        return this.length - this.offset;
    }
    set remaining(v) {
        this.offset = this.length - v;
    }
    static makeViewOf(typ, view) {
        if (view instanceof typ) {
            return view;
        }
        if (view instanceof ArrayBuffer) {
            return new typ(view, 0, view.byteLength);
        }
        return new typ(view.buffer, view.byteOffset, view.byteLength);
    }
    constructor(view, version) {
        this.version = version;
        this.view = Reader.makeViewOf(DataView, view);
    }
    bump(delta) {
        let r = this.offset;
        this.offset += delta;
        return r;
    }
    subreader(length) {
        let start = this.bump(length);
        return new Reader(new DataView(this.view.buffer, this.view.byteOffset + start, length), this.version);
    }
    array(length) {
        let start = this.bump(length);
        return new Uint8Array(this.view.buffer, this.view.byteOffset + start, length);
    }
    isAfter(ver) {
        return CacheVersion.isAfter(this.version, ver);
    }
    u8() {
        return this.view.getUint8(this.bump(1));
    }
    u8p1() {
        return this.u8() + 1;
    }
    i8() {
        return this.view.getInt8(this.bump(1));
    }
    u16() {
        return this.view.getUint16(this.bump(2));
    }
    u16n() {
        let v = this.view.getUint16(this.bump(2));
        return v == 0xFFFF ? -1 : v;
    }
    i16() {
        return this.view.getInt16(this.bump(2));
    }
    u8o16() {
        if (this.view.getUint8(this.offset) < 128) {
            return this.u8();
        }
        else {
            return this.u16() - 0x8000;
        }
    }
    u8o16m1() {
        if (this.view.getUint8(this.offset) < 128) {
            return this.u8() - 1;
        }
        else {
            return this.u16() - 0x8001;
        }
    }
    u24() {
        let off = this.bump(3);
        return (this.view.getUint8(off) << 16) | this.view.getUint16(off + 1);
    }
    i32() {
        return this.view.getInt32(this.bump(4));
    }
    s2o4n() {
        if (this.view.getUint8(this.offset) & 0x80) {
            return this.i32() & (-1 >>> 1);
        }
        else {
            return this.u16n();
        }
    }
    i64() {
        return this.view.getBigInt64(this.bump(8));
    }
    string() {
        let s = "";
        for (let c; (c = this.u8()) != 0;) {
            s += cp1252CharMap[c];
        }
        return s;
    }
    vString() {
        if (this.u8() != 0) {
            throw new Error("invalid string");
        }
        return this.string();
    }
    stringNullHidden() {
        let s = this.string();
        if (s == "hidden") {
            return null;
        }
        return s;
    }
    params() {
        let count = this.u8();
        let out = new Params();
        for (let i = 0; i < count; i++) {
            let type = this.u8();
            let param = this.u24();
            switch (type) {
                case 0:
                    out.set(param, this.i32());
                    break;
                case 1:
                    out.set(param, this.string());
                    break;
                default:
                    throw new Error(`invalid type in param table ${type}`);
            }
        }
        return out;
    }
    kit() {
        let id = this.u16();
        if (id === 0) {
            return undefined;
        }
        else if (id >= 512) {
            return { item: (id - 512) };
        }
        else if (id >= 256) {
            return { kit: (id - 256) };
        }
        else {
            throw new Error(`invalid KitOrItem ${id}`);
        }
    }
    u32o16() {
        if (this.view.getUint8(this.offset) & 0x80) {
            return this.i32() & (-1 >>> 1);
        }
        else {
            return this.u16();
        }
    }
    u32o16n() {
        if (this.view.getUint8(this.offset) & 0x80) {
            return this.i32() & (-1 >>> 1);
        }
        else {
            return this.u16n();
        }
    }
    leVarInt() {
        let v = 0;
        let shift = 0;
        let octet;
        do {
            octet = this.u8();
            v |= (octet & 127) << shift;
            shift += 7;
        } while (octet > 127);
        return v;
    }
}