import AVFoundation
import Photos
import SwiftUI
import UIKit

class MediaManager: NSObject, ObservableObject {
    // @Published var photos: [UIImage] = []
    @Published var cameraFeed: UIImage?

    // @Published var galleryAccessLevel: PHAuthorizationStatus = .notDetermined
    @Published var cameraAccessLevel: AVAuthorizationStatus = AVCaptureDevice.authorizationStatus(for: .video)

    override init() {
        super.init()
        NotificationCenter.default.addObserver(self, selector: #selector(appDidBecomeActive), name: UIApplication.didBecomeActiveNotification, object: nil)

        // DispatchQueue.main.async { [weak self] in
        //     // self?.fetchPhotos()
        // }
    }

    // private func fetchPhotos() {
    //     galleryAccessLevel = PHPhotoLibrary.authorizationStatus()
    //
    //     let fetchOptions = PHFetchOptions()
    //     fetchOptions.sortDescriptors = [NSSortDescriptor(key: "creationDate", ascending: false)]
    //     let assets = PHAsset.fetchAssets(with: .image, options: fetchOptions)
    //
    //     let manager = PHImageManager.default()
    //     let option = PHImageRequestOptions()
    //     option.isSynchronous = true
    //
    //     assets.enumerateObjects { asset, _, _ in
    //         manager.requestImage(for: asset, targetSize: CGSize(width: 200, height: 200), contentMode: .aspectFill, options: option) { image, _ in
    //             if let image = image {
    //                 DispatchQueue.main.async {
    //                     self.photos.append(image)
    //                 }
    //             }
    //         }
    //     }
    // }

    private func setupCameraFeed() {
        cameraAccessLevel = AVCaptureDevice.authorizationStatus(for: .video)

        let captureSession = AVCaptureSession()
        captureSession.sessionPreset = .medium

        guard let backCamera = AVCaptureDevice.default(.builtInWideAngleCamera, for: .video, position: .back) else {
            print("Unable to access the back camera!")
            return
        }

        do {
            let input = try AVCaptureDeviceInput(device: backCamera)
            if captureSession.canAddInput(input) {
                captureSession.addInput(input)
            }
        } catch {
            print("Error Unable to initialize back camera:  \(error.localizedDescription)")
        }

        let videoOutput = AVCaptureVideoDataOutput()
        videoOutput.setSampleBufferDelegate(self, queue: DispatchQueue(label: "videoQueue"))
        if captureSession.canAddOutput(videoOutput) {
            captureSession.addOutput(videoOutput)
        }

        captureSession.startRunning()
    }
}

extension MediaManager: AVCaptureVideoDataOutputSampleBufferDelegate {
    func captureOutput(_: AVCaptureOutput, didOutput sampleBuffer: CMSampleBuffer, from _: AVCaptureConnection) {
        print("Capturing output started")
        guard let pixelBuffer = CMSampleBufferGetImageBuffer(sampleBuffer) else {
            return
        }

        let ciImage = CIImage(cvPixelBuffer: pixelBuffer)
        let context = CIContext()
        guard let cgImage = context.createCGImage(ciImage, from: ciImage.extent) else {
            return
        }

        DispatchQueue.main.async {
            self.cameraFeed = UIImage(cgImage: cgImage)
            print("Updated camera feed")
        }
    }
}

extension MediaManager {
    func openAppSettings() {
        if
            let appSettingsUrl = URL(string: UIApplication.openSettingsURLString),
            UIApplication.shared.canOpenURL(appSettingsUrl)
        {
            UIApplication.shared.open(appSettingsUrl, completionHandler: nil)
        }
    }

    @objc private func appDidBecomeActive() {
        // Update access levels
        // galleryAccessLevel = PHPhotoLibrary.authorizationStatus()
        cameraAccessLevel = AVCaptureDevice.authorizationStatus(for: .video)
        setupCameraFeed()
    }
}