Generate video thumbnails

CHDataManagement/Generator/ImageGenerator.swift

@@ -2,6 +2,7 @@ import Foundation
 import AppKit
 import SDWebImageAVIFCoder
 import SDWebImageWebPCoder
+import AVFoundation
 
 final class ImageGenerator {
 
@@ -162,10 +163,9 @@ final class ImageGenerator {
     }
 
     private func createAvif(image: NSBitmapImageRep, quality: CGFloat) -> Data? {
-        return Data()
-//        let newImage = NSImage(size: image.size)
-//        newImage.addRepresentation(image)
-//        return SDImageAVIFCoder.shared.encodedData(with: newImage, format: .AVIF, options: [.encodeCompressionQuality: quality])
+        let newImage = NSImage(size: image.size)
+        newImage.addRepresentation(image)
+        return SDImageAVIFCoder.shared.encodedData(with: newImage, format: .AVIF, options: [.encodeCompressionQuality: quality])
     }
 
     private func createWebp(image: NSBitmapImageRep, quality: CGFloat) -> Data? {
@@ -173,4 +173,63 @@ final class ImageGenerator {
         newImage.addRepresentation(image)
         return SDImageWebPCoder.shared.encodedData(with: newImage, format: .webP, options: [.encodeCompressionQuality: quality])
     }
+
+    // MARK: Video thumbnails
+
+    @discardableResult
+    func createVideoThumbnail(for videoId: String) async -> Bool {
+        guard let image = await storage.with(file: videoId, perform: generateThumbnail) else {
+            print("Failed to generate thumbnail image for video \(videoId)")
+            return false
+        }
+        let scaled = create(image: image, width: image.size.width, height: image.size.height)
+        guard let data = scaled.representation(using: .jpeg, properties: [.compressionFactor: NSNumber(value: 0.6)]) else {
+            print("Failed to get thumbnail jpg data of video \(videoId)")
+            return false
+        }
+        if !storage.save(thumbnail: data, for: videoId) {
+            print("Failed to save thumbnail of video \(videoId)")
+        }
+        print("Generated video thumbnail for \(videoId)")
+        return true
+    }
+
+    private func generateThumbnail(for url: URL) async -> NSImage? {
+        let time = CMTime(seconds: 1, preferredTimescale: 600)
+        let asset = AVURLAsset(url: url)
+        let imageGenerator = AVAssetImageGenerator(asset: asset)
+        imageGenerator.appliesPreferredTrackTransform = true // Correct for orientation
+        return await withCheckedContinuation { continuation in
+            imageGenerator.generateCGImageAsynchronously(for: time) { cgImage, _, error in
+                if let error {
+                    print("Error generating thumbnail for \(url.path()): \(error.localizedDescription)")
+                }
+                if let cgImage {
+                    let image = NSImage(cgImage: cgImage, size: NSSize(width: cgImage.width, height: cgImage.height))
+                    continuation.resume(returning: image)
+                } else {
+                    continuation.resume(returning: nil)
+                }
+            }
+        }
+    }
+
+    func getVideoDuration(for videoId: String) async -> TimeInterval? {
+        guard let duration = await storage.with(file: videoId, perform: getVideoDuration) else {
+            print("Failed to determine duration for video \(videoId)")
+            return nil
+        }
+        return duration
+    }
+
+    private func getVideoDuration(url: URL) async -> TimeInterval? {
+        let asset = AVURLAsset(url: url)
+        do {
+            let duration = try await asset.load(.duration)
+            return CMTimeGetSeconds(duration)
+        } catch {
+            print("ImageGenerator: Failed to determine video duration: \(error.localizedDescription)")
+            return nil
+        }
+    }
 }