From 6a98e3315b1017866ab4f958f28682604a2a380a Mon Sep 17 00:00:00 2001
From: Mikael Finstad <finstaden@gmail.com>
Date: Tue, 6 Aug 2024 00:55:49 +0200
Subject: [PATCH] allow relative timeline seek #2056

---
 src/renderer/src/App.tsx           | 17 ++++++++++-------
 src/renderer/src/dialogs/index.tsx | 25 +++++++++++++++++++------
 2 files changed, 29 insertions(+), 13 deletions(-)

diff --git a/src/renderer/src/App.tsx b/src/renderer/src/App.tsx
index 07125062..830d64fd 100644
--- a/src/renderer/src/App.tsx
+++ b/src/renderer/src/App.tsx
@@ -79,7 +79,7 @@ import { formatDuration, parseDuration } from './util/duration';
 import { adjustRate } from './util/rate-calculator';
 import { askExtractFramesAsImages } from './dialogs/extractFrames';
 import { askForHtml5ifySpeed } from './dialogs/html5ify';
-import { askForOutDir, askForImportChapters, promptTimeOffset, askForFileOpenAction, confirmExtractAllStreamsDialog, showCleanupFilesDialog, showDiskFull, showExportFailedDialog, showConcatFailedDialog, openYouTubeChaptersDialog, showRefuseToOverwrite, openDirToast, openExportFinishedToast, openConcatFinishedToast, showOpenDialog, showMuxNotSupported } from './dialogs';
+import { askForOutDir, askForImportChapters, promptTimecode, askForFileOpenAction, confirmExtractAllStreamsDialog, showCleanupFilesDialog, showDiskFull, showExportFailedDialog, showConcatFailedDialog, openYouTubeChaptersDialog, showRefuseToOverwrite, openDirToast, openExportFinishedToast, openConcatFinishedToast, showOpenDialog, showMuxNotSupported } from './dialogs';
 import { openSendReportDialog } from './reporting';
 import { fallbackLng } from './i18n';
 import { createSegment, getCleanCutSegments, findSegmentsAtCursor, sortSegments, convertSegmentsToChapters, hasAnySegmentOverlap, isDurationValid, playOnlyCurrentSegment, getSegmentTags } from './segments';
@@ -1736,17 +1736,20 @@ function App() {
 
   const goToTimecode = useCallback(async () => {
     if (!filePath) return;
-    const timecode = await promptTimeOffset({
+    const timecode = await promptTimecode({
       initialValue: formatTimecode({ seconds: commandedTimeRef.current }),
       title: i18n.t('Seek to timecode'),
+      text: i18n.t('Use + and - for relative seek'),
+      allowRelative: true,
       inputPlaceholder: timecodePlaceholder,
       parseTimecode,
     });
 
     if (timecode === undefined) return;
 
-    userSeekAbs(timecode);
-  }, [filePath, formatTimecode, parseTimecode, timecodePlaceholder, userSeekAbs]);
+    if (timecode.relDirection != null) seekRel(timecode.duration * timecode.relDirection);
+    else userSeekAbs(timecode.duration);
+  }, [filePath, formatTimecode, parseTimecode, seekRel, timecodePlaceholder, userSeekAbs]);
 
   const goToTimecodeDirect = useCallback(async ({ time: timeStr }: { time: string }) => {
     if (!filePath) return;
@@ -1819,7 +1822,7 @@ function App() {
   }, [customOutDir, filePath, html5ifyAndLoad, hasVideo, hasAudio, rememberConvertToSupportedFormat, setWorking]);
 
   const askStartTimeOffset = useCallback(async () => {
-    const newStartTimeOffset = await promptTimeOffset({
+    const newStartTimeOffset = await promptTimecode({
       initialValue: startTimeOffset !== undefined ? formatTimecode({ seconds: startTimeOffset }) : undefined,
       title: i18n.t('Set custom start time offset'),
       text: i18n.t('Instead of video apparently starting at 0, you can offset by a specified value. This only applies to the preview inside LosslessCut and does not modify the file in any way. (Useful for viewing/cutting videos according to timecodes)'),
@@ -1827,9 +1830,9 @@ function App() {
       parseTimecode,
     });
 
-    if (newStartTimeOffset === undefined) return;
+    if (newStartTimeOffset === undefined || newStartTimeOffset.duration < 0) return;
 
-    setStartTimeOffset(newStartTimeOffset);
+    setStartTimeOffset(newStartTimeOffset.duration);
   }, [formatTimecode, parseTimecode, startTimeOffset, timecodePlaceholder]);
 
   const toggleKeyboardShortcuts = useCallback(() => setKeyboardShortcutsVisible((v) => !v), []);
diff --git a/src/renderer/src/dialogs/index.tsx b/src/renderer/src/dialogs/index.tsx
index 1cb545bc..05c4aa3b 100644
--- a/src/renderer/src/dialogs/index.tsx
+++ b/src/renderer/src/dialogs/index.tsx
@@ -18,8 +18,10 @@ import { ParseTimecode, SegmentBase } from '../types';
 const { dialog, shell } = window.require('@electron/remote');
 
 
-export async function promptTimeOffset({ initialValue, title, text, inputPlaceholder, parseTimecode }: { initialValue?: string | undefined, title: string, text?: string | undefined, inputPlaceholder: string, parseTimecode: ParseTimecode }) {
-  const { value } = await Swal.fire({
+export async function promptTimecode({ initialValue, title, text, inputPlaceholder, parseTimecode, allowRelative = false }: {
+  initialValue?: string | undefined, title: string, text?: string | undefined, inputPlaceholder: string, parseTimecode: ParseTimecode, allowRelative?: boolean,
+}) {
+  const { value } = await Swal.fire<string>({
     title,
     text,
     input: 'text',
@@ -35,11 +37,22 @@ export async function promptTimeOffset({ initialValue, title, text, inputPlaceho
     return undefined;
   }
 
-  const duration = parseTimecode(value);
-  // Invalid, try again
-  if (duration === undefined) return promptTimeOffset({ initialValue: value, title, text, inputPlaceholder, parseTimecode });
+  let relDirection: number | undefined;
+  if (allowRelative) {
+    if (value.startsWith('-')) relDirection = -1;
+    else if (value.startsWith('+')) relDirection = 1;
+  }
 
-  return duration;
+  const value2 = allowRelative ? value.replace(/^[+-]/, '') : value;
+
+  const duration = parseTimecode(value2);
+  // Invalid, try again
+  if (duration === undefined) return promptTimecode({ initialValue: value, title, text, inputPlaceholder, parseTimecode, allowRelative });
+
+  return {
+    duration,
+    relDirection,
+  };
 }
 
 // https://github.com/mifi/lossless-cut/issues/1495