@hamstudy/flamp/dist/compressor.js

JavaScript Amateur Multicast Protocol AMP-2 Version 3 Implemented from specification document http://www.w1hkj.com/files/flamp/Amp-2.V3.0.Protocol.pdf • Version 1.0.0 - W5ALT, Walt Fair, Jr. (Derived From) • Version 2.0.0 - W1HKJ, Dave Freese, w

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.Compressor = void 0;
const lzma_1 = require("./lzma");
class CompressorHolder {
    default;
    cMap = {};
    constructor() {
        const PREFIX_BYTES = new Uint8Array([
            0x02,
            ...[0x4c, 0x5a, 0x4d, 0x41], // LZMA
        ]);
        const prefix = String.fromCharCode(...PREFIX_BYTES);
        this.addCompressor({
            prefix,
            compress: (str) => {
                const compressed = (0, lzma_1.encodeSync)(str, 1);
                const out = new Uint8Array(PREFIX_BYTES.length + compressed.length);
                out.set(PREFIX_BYTES, 0);
                out.set(compressed, PREFIX_BYTES.length);
                return out;
            },
            decompress: (str) => {
                if (str.startsWith(prefix)) {
                    return (0, lzma_1.decodeSync)(str.substring(prefix.length));
                }
                else {
                    throw new Error("Invalid compressed string");
                }
            },
        });
    }
    addCompressor(compressor) {
        this.default = compressor.prefix;
        this.cMap[compressor.prefix] = compressor;
    }
    getCompressor(prefix = this.default) {
        return this.cMap[prefix];
    }
    getDecompressor(buffer) {
        for (let c of Object.values(this.cMap)) {
            if (buffer.substring(0, c.prefix.length) == c.prefix) {
                return c;
            }
        }
        return null;
    }
}
exports.Compressor = new CompressorHolder();