iptvnator/apps/electron-backend/src/app/workers/epg-stream-decoder.spec.ts

import { Readable } from 'stream';
import { brotliCompressSync, gzipSync } from 'zlib';
import { createDecodedEpgStream } from './epg-stream-decoder';
import { StreamingEpgParser } from './epg-streaming-parser';

const xmltvFixture =
    '<?xml version="1.0" encoding="utf-8" ?>' +
    '<tv><channel id="test"><display-name>Test Channel</display-name></channel></tv>';

async function collectDecodedText(stream: Readable): Promise<string> {
    const chunks: Buffer[] = [];

    for await (const chunk of stream) {
        chunks.push(Buffer.isBuffer(chunk) ? chunk : Buffer.from(chunk));
    }

    return Buffer.concat(chunks).toString('utf-8');
}

function parseChannelCount(xml: string): number {
    const parser = new StreamingEpgParser(
        () => undefined,
        () => undefined,
        () => undefined
    );

    parser.write(xml);
    return parser.finish().totalChannels;
}

describe('createDecodedEpgStream', () => {
    it('decodes Brotli transfer-encoded XML before SAX parsing', async () => {
        const decodedText = await collectDecodedText(
            createDecodedEpgStream(
                Readable.from([brotliCompressSync(xmltvFixture)]),
                { 'content-encoding': 'br' },
                false
            )
        );

        expect(decodedText.startsWith('<?xml')).toBe(true);
        expect(parseChannelCount(decodedText)).toBe(1);
    });

    it('decodes gzip transfer-encoded XML before SAX parsing', async () => {
        const decodedText = await collectDecodedText(
            createDecodedEpgStream(
                Readable.from([gzipSync(xmltvFixture)]),
                { 'content-encoding': 'gzip' },
                false
            )
        );

        expect(decodedText.startsWith('<?xml')).toBe(true);
        expect(parseChannelCount(decodedText)).toBe(1);
    });

    it('keeps plain XML readable when no transfer encoding is present', async () => {
        const decodedText = await collectDecodedText(
            createDecodedEpgStream(
                Readable.from([Buffer.from(xmltvFixture)]),
                {},
                false
            )
        );

        expect(decodedText.startsWith('<?xml')).toBe(true);
        expect(parseChannelCount(decodedText)).toBe(1);
    });

    it('decodes gzip XML payloads after transfer decoding', async () => {
        const transferEncodedPayload = gzipSync(gzipSync(xmltvFixture));

        const decodedText = await collectDecodedText(
            createDecodedEpgStream(
                Readable.from([transferEncodedPayload]),
                { 'content-encoding': 'gzip' },
                true
            )
        );

        expect(decodedText.startsWith('<?xml')).toBe(true);
        expect(parseChannelCount(decodedText)).toBe(1);
    });
});