fix: address final review findings (clip reset, codecs, paths, timeline)

Co-authored-by: Cursor <cursoragent@cursor.com>

src-tauri/Cargo.lock

@@ -3297,6 +3297,7 @@ dependencies = [
 name = "tauri-app"
 version = "0.1.0"
 dependencies = [
+ "dirs",
  "serde",
  "serde_json",
  "tauri",

src-tauri/Cargo.toml

@@ -29,6 +29,7 @@ tokio = { version = "1.53.1", features = ["full"] }
 thiserror = "2.0.20"
 uuid = { version = "1.26.1", features = ["v4"] }
 tempfile = "3.27.0"
+dirs = "6.0.0"
 
 
 # Read the optimization guideline for more details: https://tauri.app/concept/size/#cargo-configuration

src-tauri/src/commands/export.rs

@@ -25,6 +25,7 @@ pub async fn export_clips(
     on_event: Channel<ExportEvent>,
 ) -> Result<Vec<String>, String> {
     tokio::task::spawn_blocking(move || {
+        let output_directory = clip_exporter::expand_tilde_path(&config.output_directory);
         let ext = clip_exporter::get_extension(&config.source_file_path, &config.cut_mode);
 
         match config.export_scope {
@@ -40,7 +41,7 @@ pub async fn export_clips(
                     });
 
                     let output = clip_exporter::generate_output_path(
-                        &config.output_directory,
+                        &output_directory,
                         &config.video_title,
                         &clip.label,
                         &ext,
@@ -69,7 +70,7 @@ pub async fn export_clips(
                 });
 
                 let output = clip_exporter::generate_output_path(
-                    &config.output_directory,
+                    &output_directory,
                     &config.video_title,
                     "Merged",
                     &ext,

src-tauri/src/services/clip_exporter.rs

@@ -23,11 +23,20 @@ pub fn build_ffmpeg_args(
             args.extend(["-c".to_string(), "copy".to_string()]);
         }
         CutMode::Precise { format: _ } => {
+            let ext = Path::new(output)
+                .extension()
+                .map(|e| e.to_string_lossy().to_ascii_lowercase())
+                .unwrap_or_default();
+            let (video_codec, audio_codec) = match ext.as_str() {
+                "webm" => ("libvpx-vp9", "libopus"),
+                "mp4" | "mkv" => ("libx264", "aac"),
+                _ => ("libx264", "aac"),
+            };
             args.extend([
                 "-c:v".to_string(),
-                "libx264".to_string(),
+                video_codec.to_string(),
                 "-c:a".to_string(),
-                "aac".to_string(),
+                audio_codec.to_string(),
             ]);
         }
     }
@@ -36,6 +45,20 @@ pub fn build_ffmpeg_args(
     args
 }
 
+pub fn expand_tilde_path(path: &str) -> String {
+    if path == "~" {
+        return dirs::home_dir()
+            .map(|p| p.to_string_lossy().to_string())
+            .unwrap_or_else(|| path.to_string());
+    }
+    if let Some(rest) = path.strip_prefix("~/") {
+        if let Some(home) = dirs::home_dir() {
+            return home.join(rest).to_string_lossy().to_string();
+        }
+    }
+    path.to_string()
+}
+
 pub fn generate_output_path(
     output_dir: &str,
     video_title: &str,
@@ -206,6 +229,18 @@ mod tests {
         let args = build_ffmpeg_args(&clip, "input.mp4", "output.mp4", &mode);
         assert!(args.contains(&"-c:v".to_string()));
         assert!(args.contains(&"libx264".to_string()));
+        assert!(args.contains(&"aac".to_string()));
+
+        let webm_args = build_ffmpeg_args(&clip, "input.mp4", "output.webm", &mode);
+        assert!(webm_args.contains(&"libvpx-vp9".to_string()));
+        assert!(webm_args.contains(&"libopus".to_string()));
+    }
+
+    #[test]
+    fn test_expand_tilde_path() {
+        let expanded = expand_tilde_path("~/Videos");
+        assert!(!expanded.starts_with("~/"));
+        assert!(expanded.ends_with("Videos") || expanded.contains("Videos"));
     }
 
     #[test]

src/App.svelte

@@ -10,7 +10,8 @@
   import ExportDialog from '$lib/components/ExportDialog.svelte';
   import { loadPreferences } from '$lib/stores/preferences.svelte';
   import { getSelectedClipId, removeClip } from '$lib/stores/clips.svelte';
-  import { adjustShuttle } from '$lib/transport/playback';
+  import { adjustShuttle, resetShuttleRate } from '$lib/transport/playback';
+  import { session } from '$lib/stores/videoSession.svelte';
   import type { TransportKeyAction } from '$lib/transport/playback';
 
   let showSetupWizard = $state(true);
@@ -24,6 +25,13 @@
     loadPreferences();
   });
 
+  $effect(() => {
+    if (session.status === 'resolving') {
+      shuttleRate = 1;
+      resetShuttleRate();
+    }
+  });
+
   function dispatchTransport(action: TransportKeyAction) {
     transportControls?.handleKeyAction(action);
   }

src/lib/components/Timeline.svelte

@@ -31,7 +31,9 @@
 
   $effect(() => {
     if (session.duration > 0) {
+      timelineState.visibleStart = 0;
       timelineState.visibleEnd = session.duration;
+      timelineState.zoom = 1;
     }
   });
 

src/lib/stores/videoSession.svelte.ts

@@ -8,6 +8,7 @@ import {
   extractWaveform,
 } from '$lib/bindings/mediaAnalysis';
 import { clearThumbnailCache } from '$lib/timeline/thumbnailRenderer';
+import { clearAll as clearAllClips } from '$lib/stores/clips.svelte';
 
 export type SessionStatus = 'idle' | 'resolving' | 'ready' | 'error';
 export type DownloadStatus = 'idle' | 'downloading' | 'complete' | 'failed';
@@ -32,6 +33,7 @@ export const session = $state({
 });
 
 export function setMetadata(meta: VideoMetadata) {
+  clearAllClips();
   session.url = meta.url;
   session.title = meta.title;
   session.duration = meta.duration;
@@ -73,6 +75,7 @@ export function setError(msg: string) {
 }
 
 export function setResolving() {
+  clearAllClips();
   clearMediaFields();
   session.status = 'resolving';
   session.error = null;

src/lib/timeline/interactions.ts

@@ -17,6 +17,13 @@ export function computeZoom(
   duration: number
 ): { visibleStart: number; visibleEnd: number; zoom: number } {
   const currentRange = state.visibleEnd - state.visibleStart;
+  if (currentRange <= 0) {
+    return {
+      visibleStart: state.visibleStart,
+      visibleEnd: state.visibleEnd,
+      zoom: state.zoom,
+    };
+  }
   const newRange = currentRange / factor;
   const clampedRange = Math.max(MIN_VISIBLE_RANGE, Math.min(newRange, duration));
 

src/lib/transport/playback.ts

@@ -44,6 +44,13 @@ export function jumpKeyframe(direction: 1 | -1) {
   }
 }
 
+export function resetShuttleRate() {
+  const videoEl = document.querySelector('video');
+  if (videoEl) {
+    videoEl.playbackRate = 1;
+  }
+}
+
 export function adjustShuttle(dir: 1 | -1, shuttleRate: number): number {
   const videoEl = document.querySelector('video');
   if (!videoEl) return shuttleRate;