[dyad] Implement video cutting - wrote 4 file(s), added @ffmpeg/ffmpeg, @ffmpeg/util package(s)

src/components/video-editor.tsx

@@ -1,26 +1,39 @@
 "use client";
 
-import { useState, useRef, ChangeEvent, SyntheticEvent } from "react";
+import { useState, useRef, ChangeEvent, SyntheticEvent, useEffect } from "react";
 import { Card, CardContent, CardDescription, CardHeader, CardTitle, CardFooter } from "@/components/ui/card";
 import { Button } from "@/components/ui/button";
 import { Input } from "@/components/ui/input";
 import { Label } from "@/components/ui/label";
 import { Slider } from "@/components/ui/slider";
-import { UploadCloud, Scissors, Download } from "lucide-react";
+import { Progress } from "@/components/ui/progress";
+import { UploadCloud, Scissors, Download, Loader2 } from "lucide-react";
+import { getFFmpeg } from "@/lib/ffmpeg";
+import { fetchFile } from "@ffmpeg/util";
 
 export function VideoEditor() {
   const [videoSrc, setVideoSrc] = useState<string | null>(null);
   const [videoFile, setVideoFile] = useState<File | null>(null);
   const [duration, setDuration] = useState(0);
   const [trimValues, setTrimValues] = useState([0, 0]);
+  const [isTrimming, setIsTrimming] = useState(false);
+  const [trimmedVideoUrl, setTrimmedVideoUrl] = useState<string | null>(null);
+  const [progress, setProgress] = useState(0);
   const videoRef = useRef<HTMLVideoElement>(null);
 
+  useEffect(() => {
+    // Eagerly load FFmpeg
+    getFFmpeg();
+  }, []);
+
   const handleFileChange = (event: ChangeEvent<HTMLInputElement>) => {
     const file = event.target.files?.[0];
     if (file) {
       setVideoFile(file);
       const url = URL.createObjectURL(file);
       setVideoSrc(url);
+      setTrimmedVideoUrl(null);
+      setProgress(0);
     }
   };
 
@@ -41,6 +54,52 @@ export function VideoEditor() {
       seconds
     ).padStart(2, "0")}.${String(milliseconds).padStart(3, "0")}`;
   };
+  
+  const formatTimeForFFmpeg = (timeInSeconds: number) => {
+    const hours = Math.floor(timeInSeconds / 3600);
+    const minutes = Math.floor((timeInSeconds % 3600) / 60);
+    const seconds = Math.floor(timeInSeconds % 60);
+    const milliseconds = Math.floor((timeInSeconds % 1) * 1000);
+    return `${String(hours).padStart(2, "0")}:${String(minutes).padStart(2, "0")}:${String(
+      seconds
+    ).padStart(2, "0")}.${String(milliseconds).padStart(3, "0")}`;
+  };
+
+  const handleCutVideo = async () => {
+    if (!videoFile) return;
+
+    setIsTrimming(true);
+    setTrimmedVideoUrl(null);
+    setProgress(0);
+
+    const ffmpeg = await getFFmpeg();
+
+    ffmpeg.on('progress', ({ progress }) => {
+      setProgress(Math.round(progress * 100));
+    });
+
+    await ffmpeg.writeFile(videoFile.name, await fetchFile(videoFile));
+
+    const [startTime, endTime] = trimValues;
+
+    await ffmpeg.exec([
+      '-i',
+      videoFile.name,
+      '-ss',
+      formatTimeForFFmpeg(startTime),
+      '-to',
+      formatTimeForFFmpeg(endTime),
+      '-c',
+      'copy',
+      'output.mp4',
+    ]);
+
+    const data = await ffmpeg.readFile('output.mp4');
+    const url = URL.createObjectURL(new Blob([(data as any).buffer], { type: 'video/mp4' }));
+    
+    setTrimmedVideoUrl(url);
+    setIsTrimming(false);
+  };
 
   return (
     <Card className="w-full shadow-lg rounded-2xl border">
@@ -58,10 +117,11 @@ export function VideoEditor() {
             <div className="aspect-video w-full overflow-hidden rounded-lg border">
               <video
                 ref={videoRef}
-                src={videoSrc}
+                src={trimmedVideoUrl || videoSrc}
                 controls
                 className="w-full h-full object-contain bg-black"
                 onLoadedMetadata={handleLoadedMetadata}
+                key={trimmedVideoUrl} // Re-render video element when trimmed url changes
               />
             </div>
             <div>
@@ -73,6 +133,7 @@ export function VideoEditor() {
                   max={duration}
                   step={0.1}
                   aria-label="Video trimmer"
+                  disabled={isTrimming}
                 />
                 <div className="flex justify-between text-sm font-mono text-muted-foreground">
                   <span>Start: {formatTime(trimValues[0])}</span>
@@ -80,6 +141,13 @@ export function VideoEditor() {
                 </div>
               </div>
             </div>
+            {isTrimming && (
+              <div className="space-y-2">
+                <Label>Trimming in progress...</Label>
+                <Progress value={progress} />
+                <p className="text-sm text-muted-foreground text-center">{progress}% complete</p>
+              </div>
+            )}
           </div>
         ) : (
           <div className="flex items-center justify-center w-full">
@@ -107,13 +175,19 @@ export function VideoEditor() {
       </CardContent>
       {videoSrc && (
         <CardFooter className="flex justify-end space-x-4 p-6">
-            <Button variant="outline" size="lg" disabled>
-                <Scissors className="mr-2 h-5 w-5" />
-                Cut Video
+            <Button variant="outline" size="lg" onClick={handleCutVideo} disabled={isTrimming}>
+                {isTrimming ? (
+                    <Loader2 className="mr-2 h-5 w-5 animate-spin" />
+                ) : (
+                    <Scissors className="mr-2 h-5 w-5" />
+                )}
+                {isTrimming ? "Trimming..." : "Cut Video"}
             </Button>
-            <Button variant="default" size="lg" disabled>
-                <Download className="mr-2 h-5 w-5" />
-                Export
+            <Button asChild variant="default" size="lg" disabled={!trimmedVideoUrl || isTrimming}>
+                <a href={trimmedVideoUrl!} download={`trimmed-${videoFile?.name || 'video.mp4'}`}>
+                    <Download className="mr-2 h-5 w-5" />
+                    Export
+                </a>
             </Button>
         </CardFooter>
       )}