From ce5fb17722cbc9978eaed2bcf6413b976154cb02 Mon Sep 17 00:00:00 2001
From: Tuukka Ojala <tuukka.ojala@iki.fi>
Date: Sun, 2 Feb 2025 13:46:24 +0200
Subject: [PATCH] Add keyboard shortcuts for seeking

- Seeks by 5 seconds back / forward
- Note: Pressing these shortcuts quickly in succession while transcoding is active will throw an error since the previous request hasn't had time to finish before the next one. This bug also happens with the seek bar so might perhaps be best addressed in a separate pr / commit.
---
 README.md                 |  2 ++
 docroot/js/mediaplayer.js | 27 +++++++++++++++++++++++++--
 2 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index a6dbca37..35cc1679 100644
--- a/README.md
+++ b/README.md
@@ -71,6 +71,8 @@ _LMS_ supports lyrics in `lrc` files, `txt` files, and embedded track metadata.
 * Next track: <kbd>Ctrl</kbd> + <kbd>Right</kbd>
 * Decrease volume: <kbd>Ctrl</kbd> + <kbd>Down</kbd>
 * Increase volume: <kbd>Ctrl</kbd> + <kbd>Up</kbd>
+* Seek back by 5 seconds: <kbd>Ctrl</kbd> + <kbd>Shift</kbd> + <kbd>Left</kbd>
+* Seek forward by 5 seconds: <kbd>Ctrl</kbd> + <kbd>Shift</kbd> + <kbd>Right</kbd>
 
 
 ## Installation
diff --git a/docroot/js/mediaplayer.js b/docroot/js/mediaplayer.js
index d926c5aa..f1857145 100644
--- a/docroot/js/mediaplayer.js
+++ b/docroot/js/mediaplayer.js
@@ -18,6 +18,9 @@ Object.freeze(Mode);
 // How much to increase / decrease volume when adjusting it with keyboard shortcuts
 const volumeStepAmount = 0.05;
 
+// How much to seek back / forward (in seconds) with keyboard shortcuts
+const seekAmount = 5;
+
 LMS.mediaplayer = function () {
 	let _root = {};
 	let _elems = {};
@@ -245,6 +248,18 @@ LMS.mediaplayer = function () {
 		_updateMediaSessionState();
 	}
 
+	let _seekBack = function() {
+		let currentPosition = _offset + _elems.audio.currentTime;
+		let newPosition = currentPosition - seekAmount;
+		_seekTo(Math.max(newPosition, 0));
+	}
+
+	let _seekForward = function() {
+		let currentPosition = _offset + _elems.audio.currentTime;
+		let newPosition = currentPosition + seekAmount;
+		_seekTo(Math.min(newPosition, _duration));
+	}
+
 	let _updateMediaSessionState = function() {
 		if ("mediaSession" in navigator) {
 			navigator.mediaSession.setPositionState({
@@ -346,11 +361,11 @@ LMS.mediaplayer = function () {
 				_playPause();
 				handled = true;
 			}
-			else if (event.ctrlKey && event.keyCode == 37) {
+			else if (event.ctrlKey && !event.shiftKey && event.keyCode == 37) {
 				_playPrevious();
 				handled = true;
 			}
-			else if (event.ctrlKey && event.keyCode == 39) {
+			else if (event.ctrlKey && !event.shiftKey && event.keyCode == 39) {
 				_playNext();
 				handled = true;
 			}
@@ -362,6 +377,14 @@ LMS.mediaplayer = function () {
 				_stepVolumeUp();
 				handled = true;
 			}
+			else if (event.ctrlKey && event.shiftKey && event.keyCode == 37) {
+				_seekBack();
+				handled = true;
+			}
+			else if (event.ctrlKey && event.shiftKey && event.keyCode == 39) {
+				_seekForward();
+				handled = true;
+			}
 
 			if (handled)
 				event.preventDefault();