1/*
 2 * noVNC: HTML5 VNC client
 3 * Copyright (C) 2024 The noVNC authors
 4 * Licensed under MPL 2.0 (see LICENSE.txt)
 5 *
 6 * See README.md for usage and integration instructions.
 7 *
 8 */
 9
10import Inflator from "../inflator.js";
11
12export default class ZlibDecoder {
13    constructor() {
14        this._zlib = new Inflator();
15        this._length = 0;
16    }
17
18    decodeRect(x, y, width, height, sock, display, depth) {
19        if ((width === 0) || (height === 0)) {
20            return true;
21        }
22
23        if (this._length === 0) {
24            if (sock.rQwait("ZLIB", 4)) {
25                return false;
26            }
27
28            this._length = sock.rQshift32();
29        }
30
31        if (sock.rQwait("ZLIB", this._length)) {
32            return false;
33        }
34
35        let data = new Uint8Array(sock.rQshiftBytes(this._length, false));
36        this._length = 0;
37
38        this._zlib.setInput(data);
39        data = this._zlib.inflate(width * height * 4);
40        this._zlib.setInput(null);
41
42        // Max sure the image is fully opaque
43        for (let i = 0; i < width * height; i++) {
44            data[i * 4 + 3] = 255;
45        }
46
47        display.blitImage(x, y, width, height, data, 0);
48
49        return true;
50    }
51}