release: publish Twitch VOD Manager 1.0.3

Polish navigation, settings, streamer and queue workflows; add safe pause and partial-file lifecycle handling; apply the product identity across Windows surfaces; and replace the public README with a complete English product guide and isolated screenshot.

src/main/dev-executable.test.ts

@@ -0,0 +1,41 @@
+import * as fs from 'fs';
+import * as os from 'os';
+import * as path from 'path';
+import * as ResEdit from 'resedit';
+import { afterEach, beforeEach, describe, expect, it } from 'vitest';
+import { prepareWindowsDevExecutable } from './dev-executable';
+
+let tempDirectory: string;
+
+beforeEach(() => {
+    tempDirectory = fs.mkdtempSync(path.join(os.tmpdir(), 'tvm-dev-exe-'));
+});
+
+afterEach(() => {
+    fs.rmSync(tempDirectory, { recursive: true, force: true });
+});
+
+describe.runIf(process.platform === 'win32')('prepareWindowsDevExecutable', () => {
+    it('bettet App-Icon und Produktnamen in die gestartete Entwicklungs-EXE ein', async () => {
+        const sourcePath = path.join(process.env.WINDIR || 'C:\\Windows', 'System32', 'where.exe');
+        const destinationPath = path.join(tempDirectory, 'Twitch VOD Manager.exe');
+        const iconPath = path.resolve('build/icon.ico');
+
+        await prepareWindowsDevExecutable({
+            sourcePath,
+            destinationPath,
+            iconPath,
+            version: '1.0.3'
+        });
+
+        const executable = ResEdit.NtExecutable.from(fs.readFileSync(destinationPath));
+        const resources = ResEdit.NtExecutableResource.from(executable);
+        const iconGroups = ResEdit.Resource.IconGroupEntry.fromEntries(resources.entries);
+        const versionInfo = ResEdit.Resource.VersionInfo.fromEntries(resources.entries)[0];
+        const strings = versionInfo.getStringValues(versionInfo.getAllLanguagesForStringValues()[0]);
+
+        expect(iconGroups[0].icons).toHaveLength(6);
+        expect(strings.ProductName).toBe('Twitch VOD Manager');
+        expect(strings.FileDescription).toBe('Twitch VOD Manager');
+    });
+});

src/main/dev-executable.ts

@@ -0,0 +1,71 @@
+import * as fs from 'fs';
+import * as path from 'path';
+import * as ResEdit from 'resedit';
+import { writeFileAtomicSync } from './infra/fs-atomic';
+
+export interface WindowsDevExecutableOptions {
+    sourcePath: string;
+    destinationPath: string;
+    iconPath: string;
+    version: string;
+}
+
+export async function prepareWindowsDevExecutable(options: WindowsDevExecutableOptions): Promise<string> {
+    const source = path.resolve(options.sourcePath);
+    const destination = path.resolve(options.destinationPath);
+    const icon = path.resolve(options.iconPath);
+    const stampPath = `${destination}.json`;
+    const sourceStats = fs.statSync(source);
+    const iconStats = fs.statSync(icon);
+    const fingerprint = JSON.stringify({
+        sourceSize: sourceStats.size,
+        sourceModified: sourceStats.mtimeMs,
+        iconSize: iconStats.size,
+        iconModified: iconStats.mtimeMs,
+        version: options.version
+    });
+
+    if (fs.existsSync(destination) && fs.existsSync(stampPath) && fs.readFileSync(stampPath, 'utf8') === fingerprint) {
+        return destination;
+    }
+
+    fs.mkdirSync(path.dirname(destination), { recursive: true });
+    const temporaryDestination = `${destination}.tmp`;
+    fs.copyFileSync(source, temporaryDestination);
+
+    try {
+        const executable = ResEdit.NtExecutable.from(fs.readFileSync(temporaryDestination), { ignoreCert: true });
+        const resources = ResEdit.NtExecutableResource.from(executable);
+        const versionEntries = ResEdit.Resource.VersionInfo.fromEntries(resources.entries);
+        const versionInfo = versionEntries[0] || ResEdit.Resource.VersionInfo.createEmpty();
+        const languages = versionInfo.getAllLanguagesForStringValues();
+        const language = languages[0] || { lang: 0x0409, codepage: 1200 };
+        versionInfo.setStringValues(language, {
+            FileDescription: 'Twitch VOD Manager',
+            ProductName: 'Twitch VOD Manager',
+            InternalName: 'Twitch VOD Manager',
+            OriginalFilename: 'Twitch VOD Manager.exe'
+        });
+        versionInfo.setFileVersion(options.version);
+        versionInfo.setProductVersion(options.version);
+        versionInfo.outputToResourceEntries(resources.entries);
+
+        const iconFile = ResEdit.Data.IconFile.from(fs.readFileSync(icon));
+        ResEdit.Resource.IconGroupEntry.replaceIconsForResource(
+            resources.entries,
+            1,
+            language.lang,
+            iconFile.icons.map((entry) => entry.data)
+        );
+
+        resources.outputResource(executable);
+        fs.writeFileSync(temporaryDestination, Buffer.from(executable.generate()));
+        fs.rmSync(destination, { force: true });
+        fs.renameSync(temporaryDestination, destination);
+        writeFileAtomicSync(stampPath, fingerprint);
+        return destination;
+    } catch (error) {
+        fs.rmSync(temporaryDestination, { force: true });
+        throw error;
+    }
+}

src/main/dev-reload.test.ts

@@ -0,0 +1,17 @@
+import { describe, expect, test } from 'vitest';
+import { isRendererReloadTarget } from './dev-reload';
+
+describe('isRendererReloadTarget', () => {
+    test('reloads renderer output and static renderer assets', () => {
+        expect(isRendererReloadTarget('renderer.js')).toBe(true);
+        expect(isRendererReloadTarget('renderer-settings.js')).toBe(true);
+        expect(isRendererReloadTarget('index.html')).toBe(true);
+        expect(isRendererReloadTarget('styles.css')).toBe(true);
+    });
+
+    test('does not reload for main-process output', () => {
+        expect(isRendererReloadTarget('main.js')).toBe(false);
+        expect(isRendererReloadTarget('preload.js')).toBe(false);
+        expect(isRendererReloadTarget('main/domain/config.js')).toBe(false);
+    });
+});

src/main/dev-reload.ts

@@ -0,0 +1,31 @@
+import { watch, type FSWatcher } from 'node:fs';
+
+const staticRendererAssets = new Set(['index.html', 'styles.css', 'workspace.css']);
+
+export function isRendererReloadTarget(fileName: string): boolean {
+    const normalized = fileName.replaceAll('\\', '/');
+    const baseName = normalized.split('/').at(-1) ?? '';
+    return staticRendererAssets.has(baseName) || /^renderer(?:[-.].+)?\.js$/.test(baseName);
+}
+
+export function watchRendererChanges(
+    outputDirectory: string,
+    sourceDirectory: string,
+    reload: () => void,
+): () => void {
+    let reloadTimer: NodeJS.Timeout | undefined;
+    const scheduleReload = (fileName: string | Buffer | null): void => {
+        if (!fileName || !isRendererReloadTarget(fileName.toString())) return;
+        if (reloadTimer) clearTimeout(reloadTimer);
+        reloadTimer = setTimeout(reload, 125);
+    };
+    const watchers: FSWatcher[] = [
+        watch(outputDirectory, { recursive: true }, (_, fileName) => scheduleReload(fileName)),
+        watch(sourceDirectory, { recursive: true }, (_, fileName) => scheduleReload(fileName)),
+    ];
+
+    return () => {
+        if (reloadTimer) clearTimeout(reloadTimer);
+        for (const watcher of watchers) watcher.close();
+    };
+}

src/main/domain/app-identity.test.ts

@@ -0,0 +1,15 @@
+import { describe, expect, test } from 'vitest';
+import { getWindowsAppIdentity } from './app-identity';
+
+describe('getWindowsAppIdentity', () => {
+    test('trennt Hot-Dev von der veröffentlichten Windows-Identität', () => {
+        expect(getWindowsAppIdentity(true)).toEqual({
+            name: 'Twitch VOD Manager',
+            appUserModelId: 'io.github.sucukdeluxe.twitch-vod-manager.development'
+        });
+        expect(getWindowsAppIdentity(false)).toEqual({
+            name: 'Twitch VOD Manager',
+            appUserModelId: 'io.github.sucukdeluxe.twitch-vod-manager'
+        });
+    });
+});

src/main/domain/app-identity.ts

@@ -0,0 +1,13 @@
+export interface WindowsAppIdentity {
+    name: string;
+    appUserModelId: string;
+}
+
+export function getWindowsAppIdentity(isDevelopment: boolean): WindowsAppIdentity {
+    return {
+        name: 'Twitch VOD Manager',
+        appUserModelId: isDevelopment
+            ? 'io.github.sucukdeluxe.twitch-vod-manager.development'
+            : 'io.github.sucukdeluxe.twitch-vod-manager'
+    };
+}

src/main/domain/i18n-backend.test.ts

@@ -41,6 +41,14 @@ describe('tBackend', () => {
         }
     });
 
+    test('German backend messages use native umlauts', () => {
+        const text = Object.values(BACKEND_MESSAGES.de).join('\n').toLocaleLowerCase('de-DE');
+        const forbidden = ['ungueltig', 'integritaetspruefung', 'fur ', 'benoetigt', 'prufe '];
+        for (const token of forbidden) {
+            expect(text).not.toContain(token);
+        }
+    });
+
     test('no template literal left after substitution for typical params', () => {
         // attemptFailed has {attempt}, {max}, {errorClass}, {error}
         const result = tBackend('attemptFailed', { attempt: 1, max: 3, errorClass: 'network', error: 'ETIMEDOUT' }, 'en');

src/main/domain/i18n-backend.ts

@@ -1,10 +1,10 @@
 // Backend-Messages (User-visible aus main.ts produziert). Pure: Sprache wird
-// als Parameter uebergeben statt aus globalem config geholt.
+// als Parameter übergeben statt aus globalem config geholt.
 
 export const BACKEND_MESSAGES = {
     de: {
-        invalidVodUrl: 'Ungueltige VOD-URL',
-        invalidClipUrl: 'Ungueltige Clip-URL',
+        invalidVodUrl: 'Ungültige VOD-URL',
+        invalidClipUrl: 'Ungültige Clip-URL',
         clipNotFound: 'Clip nicht gefunden',
         streamlinkAutoInstallFailed: 'Streamlink fehlt und konnte nicht automatisch installiert werden. Siehe debug.log.',
         streamlinkMissing: 'Streamlink fehlt.',
@@ -15,10 +15,10 @@ export const BACKEND_MESSAGES = {
         ffmpegSplitFailed: 'FFmpeg Split fehlgeschlagen.',
         fileTooSmall: 'Datei zu klein ({bytes} Bytes)',
         clipFileTooSmall: 'Clip-Datei zu klein ({bytes} Bytes) - Twitch hat den Stream evtl. nicht ausgeliefert.',
-        integrityNoVideo: 'Integritaetspruefung fehlgeschlagen: Kein Videostream gefunden.',
-        integrityTooShort: 'Integritaetspruefung fehlgeschlagen: Dauer zu kurz ({duration}s).',
-        integrityDurationMismatch: 'Integritaetspruefung fehlgeschlagen: {actual}s statt erwarteter ~{expected}s.',
-        integrityFailedGeneric: 'Integritaetspruefung fehlgeschlagen.',
+        integrityNoVideo: 'Integritätsprüfung fehlgeschlagen: Kein Videostream gefunden.',
+        integrityTooShort: 'Integritätsprüfung fehlgeschlagen: Dauer zu kurz ({duration}s).',
+        integrityDurationMismatch: 'Integritätsprüfung fehlgeschlagen: {actual}s statt erwarteter ~{expected}s.',
+        integrityFailedGeneric: 'Integritätsprüfung fehlgeschlagen.',
         downloadCancelled: 'Download wurde abgebrochen.',
         downloadPaused: 'Download wurde pausiert.',
         downloadFailedExitCode: 'Download fehlgeschlagen (Exit-Code {code})',
@@ -26,12 +26,12 @@ export const BACKEND_MESSAGES = {
         notAllClipPartsDownloaded: 'Nicht alle Clip-Teile konnten heruntergeladen werden.',
         notAllPartsDownloaded: 'Nicht alle Teile konnten heruntergeladen werden.',
         mergeGroupFileMissing: 'Heruntergeladene Datei {index} fehlt.',
-        diskSpaceShortFor: 'Zu wenig Speicherplatz fur {context}: frei {free}, benoetigt ~{required}.',
+        diskSpaceShortFor: 'Zu wenig Speicherplatz für {context}: frei {free}, benötigt ~{required}.',
         diskSpaceShortGeneric: 'Zu wenig Speicherplatz.',
         attemptFailed: 'Versuch {attempt}/{max} fehlgeschlagen ({errorClass}): {error}',
         retryingIn: 'Neuer Versuch in {seconds}s ({errorClass})...',
-        statusCheckingTools: 'Prufe Download-Tools...',
-        statusDownloadStarted: 'Download gestartet',
+        statusCheckingTools: 'Prüfe Download-Tools...',
+        statusDownloadStarted: 'Download wird gestartet …',
         statusBytesDownloaded: '{bytes} heruntergeladen',
         statusFetchingChatReplay: 'Chat-Replay wird heruntergeladen...',
         statusChatMessagesFetched: 'Chat-Nachrichten geladen: {count}',
@@ -70,7 +70,7 @@ export const BACKEND_MESSAGES = {
         attemptFailed: 'Attempt {attempt}/{max} failed ({errorClass}): {error}',
         retryingIn: 'Retrying in {seconds}s ({errorClass})...',
         statusCheckingTools: 'Checking download tools...',
-        statusDownloadStarted: 'Download started',
+        statusDownloadStarted: 'Starting download …',
         statusBytesDownloaded: '{bytes} downloaded',
         statusFetchingChatReplay: 'Fetching chat replay...',
         statusChatMessagesFetched: 'Chat messages fetched: {count}',

src/main/domain/migrator.ts

@@ -36,7 +36,7 @@ const CONFIG_KV_KEYS = [
     'auto_record_poll_seconds', 'filename_template_vod', 'filename_template_parts',
     'filename_template_clip', 'smart_queue_scheduler', 'prevent_duplicate_downloads',
     'persist_queue_on_restart', 'auto_resume_queue_on_startup',
-    'notify_on_each_completion',
+    'notify_on_each_completion', 'sidebar_split_view',
 ] as const;
 
 function backupOnce(srcPath: string): void {

src/main/domain/partial-download.test.ts

@@ -0,0 +1,64 @@
+import * as fs from 'fs';
+import * as os from 'os';
+import * as path from 'path';
+import { afterEach, beforeEach, describe, expect, it } from 'vitest';
+import { PartialDownloadRegistry } from './partial-download';
+
+let tempDirectory: string;
+let registryPath: string;
+
+beforeEach(() => {
+    tempDirectory = fs.mkdtempSync(path.join(os.tmpdir(), 'tvm-partial-'));
+    registryPath = path.join(tempDirectory, 'partial-downloads.json');
+});
+
+afterEach(() => {
+    fs.rmSync(tempDirectory, { recursive: true, force: true });
+});
+
+describe('PartialDownloadRegistry', () => {
+    it('veröffentlicht erst nach erfolgreichem Commit den endgültigen Dateinamen', () => {
+        const registry = new PartialDownloadRegistry(registryPath);
+        const finalPath = path.join(tempDirectory, 'video.mp4');
+        const partialPath = registry.begin(finalPath);
+
+        fs.writeFileSync(partialPath, 'vollständig');
+
+        expect(partialPath).toBe(`${finalPath}.tvm-part`);
+        expect(fs.existsSync(finalPath)).toBe(false);
+
+        registry.commit(partialPath, finalPath);
+
+        expect(fs.readFileSync(finalPath, 'utf8')).toBe('vollständig');
+        expect(fs.existsSync(partialPath)).toBe(false);
+        expect(fs.existsSync(registryPath)).toBe(false);
+    });
+
+    it('entfernt eine abgebrochene Teil-Datei', () => {
+        const registry = new PartialDownloadRegistry(registryPath);
+        const finalPath = path.join(tempDirectory, 'abbruch.mp4');
+        const partialPath = registry.begin(finalPath);
+        fs.writeFileSync(partialPath, 'unvollständig');
+
+        registry.discard(partialPath);
+
+        expect(fs.existsSync(partialPath)).toBe(false);
+        expect(fs.existsSync(finalPath)).toBe(false);
+        expect(fs.existsSync(registryPath)).toBe(false);
+    });
+
+    it('räumt nach einem simulierten Crash registrierte Teil-Dateien beim nächsten Start auf', () => {
+        const firstRun = new PartialDownloadRegistry(registryPath);
+        const finalPath = path.join(tempDirectory, 'crash.mp4');
+        const partialPath = firstRun.begin(finalPath);
+        fs.writeFileSync(partialPath, 'unvollständig');
+
+        const secondRun = new PartialDownloadRegistry(registryPath);
+        const removed = secondRun.cleanup();
+
+        expect(removed).toEqual([partialPath]);
+        expect(fs.existsSync(partialPath)).toBe(false);
+        expect(fs.existsSync(finalPath)).toBe(false);
+        expect(fs.existsSync(registryPath)).toBe(false);
+    });
+});

src/main/domain/partial-download.ts

@@ -0,0 +1,83 @@
+import * as fs from 'fs';
+import * as path from 'path';
+import { writeFileAtomicSync } from '../infra/fs-atomic';
+
+const PARTIAL_SUFFIX = '.tvm-part';
+
+export class PartialDownloadRegistry {
+    private readonly paths = new Set<string>();
+
+    constructor(private readonly registryPath: string) {
+        this.load(this.registryPath);
+        this.load(`${this.registryPath}.tmp`);
+    }
+
+    begin(finalPath: string): string {
+        const partialPath = path.resolve(`${finalPath}${PARTIAL_SUFFIX}`);
+        if (fs.existsSync(partialPath)) fs.rmSync(partialPath, { force: true });
+        this.paths.add(partialPath);
+        this.persist();
+        return partialPath;
+    }
+
+    commit(partialPath: string, finalPath: string): void {
+        const normalizedPartialPath = this.normalize(partialPath);
+        const normalizedFinalPath = path.resolve(finalPath);
+        if (!fs.existsSync(normalizedPartialPath)) throw new Error(`Teil-Datei fehlt: ${normalizedPartialPath}`);
+        if (fs.existsSync(normalizedFinalPath)) throw new Error(`Zieldatei existiert bereits: ${normalizedFinalPath}`);
+        fs.renameSync(normalizedPartialPath, normalizedFinalPath);
+        this.paths.delete(normalizedPartialPath);
+        this.persist();
+    }
+
+    discard(partialPath: string): void {
+        const normalizedPartialPath = this.normalize(partialPath);
+        if (fs.existsSync(normalizedPartialPath)) fs.rmSync(normalizedPartialPath, { force: true });
+        this.paths.delete(normalizedPartialPath);
+        this.persist();
+    }
+
+    cleanup(): string[] {
+        const removed: string[] = [];
+        for (const partialPath of this.paths) {
+            if (fs.existsSync(partialPath)) {
+                fs.rmSync(partialPath, { force: true });
+                removed.push(partialPath);
+            }
+        }
+        this.paths.clear();
+        this.persist();
+        return removed;
+    }
+
+    private normalize(filePath: string): string {
+        const normalizedPath = path.resolve(filePath);
+        if (!normalizedPath.endsWith(PARTIAL_SUFFIX)) throw new Error(`Ungültiger Teil-Dateipfad: ${normalizedPath}`);
+        return normalizedPath;
+    }
+
+    private load(filePath: string): void {
+        try {
+            if (!fs.existsSync(filePath)) return;
+            const parsed = JSON.parse(fs.readFileSync(filePath, 'utf8'));
+            const values = Array.isArray(parsed) ? parsed : parsed?.paths;
+            if (!Array.isArray(values)) return;
+            for (const value of values) {
+                if (typeof value !== 'string') continue;
+                try {
+                    this.paths.add(this.normalize(value));
+                } catch { }
+            }
+        } catch { }
+    }
+
+    private persist(): void {
+        if (this.paths.size === 0) {
+            fs.rmSync(this.registryPath, { force: true });
+            fs.rmSync(`${this.registryPath}.tmp`, { force: true });
+            return;
+        }
+        fs.mkdirSync(path.dirname(this.registryPath), { recursive: true });
+        writeFileAtomicSync(this.registryPath, JSON.stringify({ paths: [...this.paths] }, null, 2));
+    }
+}

src/main/domain/pausable-output.test.ts

@@ -0,0 +1,89 @@
+import { PassThrough, Writable } from 'stream';
+import { describe, expect, it } from 'vitest';
+import { createPausableOutput } from './pausable-output';
+
+function waitForTurn(): Promise<void> {
+    return new Promise((resolve) => setImmediate(resolve));
+}
+
+describe('createPausableOutput', () => {
+    it('setzt denselben Ausgabestrom ohne Datenverlust fort', async () => {
+        const source = new PassThrough();
+        const chunks: Buffer[] = [];
+        const target = new Writable({
+            write(chunk, _encoding, callback) {
+                chunks.push(Buffer.from(chunk));
+                callback();
+            }
+        });
+        const output = createPausableOutput(source, target);
+
+        source.write('erster-');
+        await waitForTurn();
+        output.pause();
+        source.write('zweiter-');
+        await waitForTurn();
+
+        expect(Buffer.concat(chunks).toString()).toBe('erster-');
+
+        output.resume();
+        source.end('dritter');
+        await output.finished;
+
+        expect(Buffer.concat(chunks).toString()).toBe('erster-zweiter-dritter');
+        expect(output.isPaused()).toBe(false);
+    });
+
+    it('schließt einen während der Pause beendeten Quellstrom erst nach dem Fortsetzen ab', async () => {
+        const source = new PassThrough();
+        const chunks: Buffer[] = [];
+        const target = new Writable({
+            write(chunk, _encoding, callback) {
+                chunks.push(Buffer.from(chunk));
+                callback();
+            }
+        });
+        const output = createPausableOutput(source, target);
+        let finished = false;
+        void output.finished.then(() => {
+            finished = true;
+        });
+
+        source.write('vorher-');
+        await waitForTurn();
+        output.pause();
+        source.end('nachher');
+        await waitForTurn();
+
+        expect(finished).toBe(false);
+        expect(Buffer.concat(chunks).toString()).toBe('vorher-');
+
+        output.resume();
+        await output.finished;
+
+        expect(Buffer.concat(chunks).toString()).toBe('vorher-nachher');
+    });
+
+    it('schließt Quell- und Zielstrom bei einem Abbruch zuverlässig', async () => {
+        const source = new PassThrough();
+        const chunks: Buffer[] = [];
+        const target = new Writable({
+            write(chunk, _encoding, callback) {
+                chunks.push(Buffer.from(chunk));
+                callback();
+            }
+        });
+        const output = createPausableOutput(source, target);
+
+        source.write('behalten');
+        await waitForTurn();
+        output.pause();
+
+        await output.cancel();
+        await output.finished;
+
+        expect(source.destroyed).toBe(true);
+        expect(target.destroyed).toBe(true);
+        expect(Buffer.concat(chunks).toString()).toBe('behalten');
+    });
+});

src/main/domain/pausable-output.ts

@@ -0,0 +1,74 @@
+import { Readable, Writable } from 'stream';
+
+export interface PausableOutput {
+    pause(): void;
+    resume(): void;
+    cancel(): Promise<void>;
+    isPaused(): boolean;
+    finished: Promise<void>;
+}
+
+export function createPausableOutput(source: Readable, target: Writable): PausableOutput {
+    let paused = false;
+    let settled = false;
+    let resolveFinished: () => void = () => {};
+    let rejectFinished: (error: Error) => void = () => {};
+    let resolveClosed: () => void = () => {};
+    const finished = new Promise<void>((resolve, reject) => {
+        resolveFinished = resolve;
+        rejectFinished = reject;
+    });
+    const closed = new Promise<void>((resolve) => {
+        resolveClosed = resolve;
+    });
+    const attach = () => source.pipe(target, { end: false });
+    const finish = () => {
+        if (!settled) target.end();
+    };
+
+    target.once('finish', () => {
+        settled = true;
+        resolveFinished();
+    });
+    target.once('close', () => {
+        resolveClosed();
+        if (!settled) {
+            settled = true;
+            resolveFinished();
+        }
+    });
+    target.once('error', (error) => {
+        settled = true;
+        source.destroy(error);
+        rejectFinished(error);
+    });
+    source.once('end', finish);
+    source.once('error', (error) => target.destroy(error));
+    attach();
+
+    return {
+        pause() {
+            if (paused || settled) return;
+            paused = true;
+            source.unpipe(target);
+            source.pause();
+        },
+        resume() {
+            if (!paused || settled) return;
+            paused = false;
+            attach();
+            source.resume();
+        },
+        async cancel() {
+            if (!settled) {
+                paused = false;
+                source.unpipe(target);
+                source.destroy();
+                target.destroy();
+            }
+            await closed;
+        },
+        isPaused: () => paused,
+        finished
+    };
+}

src/main/domain/vod-preview.test.ts

@@ -0,0 +1,19 @@
+import { describe, expect, test } from 'vitest';
+import { buildVodPreviewFrameUrls } from './vod-preview';
+
+describe('buildVodPreviewFrameUrls', () => {
+    test('builds four full-HD frame URLs from a Twitch thumb0 URL', () => {
+        const input = 'https://static-cdn.jtvnw.net/cf_vods/example/thumb/thumb0-1920x1080.jpg';
+
+        expect(buildVodPreviewFrameUrls(input)).toEqual([
+            'https://static-cdn.jtvnw.net/cf_vods/example/thumb/thumb0-1920x1080.jpg',
+            'https://static-cdn.jtvnw.net/cf_vods/example/thumb/thumb1-1920x1080.jpg',
+            'https://static-cdn.jtvnw.net/cf_vods/example/thumb/thumb2-1920x1080.jpg',
+            'https://static-cdn.jtvnw.net/cf_vods/example/thumb/thumb3-1920x1080.jpg'
+        ]);
+    });
+
+    test('rejects URLs that are not Twitch full-HD VOD thumbnails', () => {
+        expect(buildVodPreviewFrameUrls('https://example.invalid/thumb0-320x180.jpg')).toEqual([]);
+    });
+});

src/main/domain/vod-preview.ts

@@ -0,0 +1,20 @@
+const TWITCH_VOD_THUMBNAIL_PATTERN = /thumb0-1920x1080\.jpg$/;
+
+export function buildVodPreviewFrameUrls(thumbnailUrl: string): string[] {
+    let parsed: URL;
+    try {
+        parsed = new URL(thumbnailUrl);
+    } catch {
+        return [];
+    }
+
+    if (parsed.protocol !== 'https:' || parsed.hostname !== 'static-cdn.jtvnw.net' || !TWITCH_VOD_THUMBNAIL_PATTERN.test(parsed.pathname)) {
+        return [];
+    }
+
+    return [0, 1, 2, 3].map((index) => {
+        const frameUrl = new URL(parsed.toString());
+        frameUrl.pathname = frameUrl.pathname.replace('thumb0-1920x1080.jpg', `thumb${index}-1920x1080.jpg`);
+        return frameUrl.toString();
+    });
+}

src/main/infra/loopback-server.ts

@@ -32,7 +32,7 @@ const DEFAULT_SUCCESS = `<!doctype html><html><head><meta charset="utf-8"><title
 <style>body{font-family:system-ui,-apple-system,Segoe UI,sans-serif;background:#0e0e10;color:#efeff1;display:flex;align-items:center;justify-content:center;height:100vh;margin:0}
 .box{text-align:center;padding:2rem 3rem;background:#1f1f23;border-radius:8px}
 h1{color:#9146FF;margin:0 0 0.5rem}</style></head>
-<body><div class="box"><h1>Login erfolgreich</h1><p>Du kannst dieses Fenster jetzt schliessen.</p></div></body></html>`;
+<body><div class="box"><h1>Login erfolgreich</h1><p>Du kannst dieses Fenster jetzt schließen.</p></div></body></html>`;
 
 const DEFAULT_ERROR = `<!doctype html><html><head><meta charset="utf-8"><title>Fehler</title>
 <style>body{font-family:system-ui,-apple-system,Segoe UI,sans-serif;background:#0e0e10;color:#efeff1;display:flex;align-items:center;justify-content:center;height:100vh;margin:0}