camera: add PhotoCaptureProcessor and VideoCaptureProcessor

damus/Models/Camera/PhotoCaptureProcessor.swift

@@ -0,0 +1,91 @@
+//
+//  PhotoCaptureProcessor.swift
+//  damus
+//
+//  Created by Suhail Saqan on 8/5/23.
+//
+
+import Foundation
+import Photos
+
+class PhotoCaptureProcessor: NSObject {
+    private(set) var requestedPhotoSettings: AVCapturePhotoSettings
+    private(set) var photoOutput: AVCapturePhotoOutput?
+
+    lazy var context = CIContext()
+    var photoData: Data?
+    private var maxPhotoProcessingTime: CMTime?
+
+    private let willCapturePhotoAnimation: () -> Void
+    private let completionHandler: (PhotoCaptureProcessor) -> Void
+    private let photoProcessingHandler: (Bool) -> Void
+
+    init(with requestedPhotoSettings: AVCapturePhotoSettings,
+         photoOutput: AVCapturePhotoOutput?,
+         willCapturePhotoAnimation: @escaping () -> Void,
+         completionHandler: @escaping (PhotoCaptureProcessor) -> Void,
+         photoProcessingHandler: @escaping (Bool) -> Void) {
+        self.requestedPhotoSettings = requestedPhotoSettings
+        self.willCapturePhotoAnimation = willCapturePhotoAnimation
+        self.completionHandler = completionHandler
+        self.photoProcessingHandler = photoProcessingHandler
+        self.photoOutput = photoOutput
+    }
+
+    func capturePhoto(settings: AVCapturePhotoSettings) {
+        if let photoOutput = self.photoOutput {
+            photoOutput.capturePhoto(with: settings, delegate: self)
+        }
+    }
+}
+
+extension PhotoCaptureProcessor: AVCapturePhotoCaptureDelegate {
+    func photoOutput(_ output: AVCapturePhotoOutput, willBeginCaptureFor resolvedSettings: AVCaptureResolvedPhotoSettings) {
+        maxPhotoProcessingTime = resolvedSettings.photoProcessingTimeRange.start + resolvedSettings.photoProcessingTimeRange.duration
+    }
+
+    func photoOutput(_ output: AVCapturePhotoOutput, willCapturePhotoFor resolvedSettings: AVCaptureResolvedPhotoSettings) {
+        DispatchQueue.main.async {
+            self.willCapturePhotoAnimation()
+        }
+
+        guard let maxPhotoProcessingTime = maxPhotoProcessingTime else {
+            return
+        }
+
+        DispatchQueue.main.async {
+            self.photoProcessingHandler(true)
+        }
+
+        let oneSecond = CMTime(seconds: 2, preferredTimescale: 1)
+        if maxPhotoProcessingTime > oneSecond {
+            DispatchQueue.main.async {
+                self.photoProcessingHandler(true)
+            }
+        }
+    }
+
+    func photoOutput(_ output: AVCapturePhotoOutput, didFinishProcessingPhoto photo: AVCapturePhoto, error: Error?) {
+        DispatchQueue.main.async {
+            self.photoProcessingHandler(false)
+        }
+
+        if let error = error {
+            print("Error capturing photo: \(error)")
+        } else {
+            photoData = photo.fileDataRepresentation()
+
+        }
+    }
+
+    func photoOutput(_ output: AVCapturePhotoOutput, didFinishCaptureFor resolvedSettings: AVCaptureResolvedPhotoSettings, error: Error?) {
+        if let error = error {
+            print("Error capturing photo: \(error)")
+            return
+        }
+
+        DispatchQueue.main.async {
+            self.completionHandler(self)
+        }
+    }
+}