import AVFoundation
import Photos
import SwiftUI

struct AttachmentMediaPickerView: View {
    @State private var isCameraAccessGranted = AVCaptureDevice.authorizationStatus(for: .video) == .authorized

    @State private var isGalleryAccessGranted = PHPhotoLibrary.authorizationStatus() == .authorized
    @State private var images = [UIImage]()

    let gridSize = UIScreen.main.bounds.width / 3

    var body: some View {
        let columns = Array(repeating: GridItem(.flexible(), spacing: 0), count: 3)

        ScrollView(showsIndicators: false) {
            LazyVGrid(columns: columns, spacing: 0) {
                // For camera
                if isCameraAccessGranted {
                    ZStack {
                        CameraView()
                            .aspectRatio(1, contentMode: .fit)
                            .frame(maxWidth: .infinity)
                        Image(systemName: "camera")
                            .resizable()
                            .aspectRatio(contentMode: .fit)
                            .frame(width: 40, height: 40)
                            .foregroundColor(.white)
                            .padding(8)
                            .background(Color.black.opacity(0.5))
                            .clipShape(Circle())
                            .padding(8)
                    }
                } else {
                    Button {
                        openAppSettings()
                    } label: {
                        ZStack {
                            Rectangle()
                                .fill(Color.Main.backgroundLight)
                                .overlay {
                                    VStack {
                                        Image(systemName: "camera")
                                            .foregroundColor(.Material.tortoiseLight300)
                                            .font(.system(size: 30))
                                        Text("Allow camera access")
                                            .foregroundColor(.Main.black)
                                            .font(.body3)
                                    }
                                }
                                .frame(height: 100)
                        }
                    }
                }

                // For pictures
                if isGalleryAccessGranted {
                    ForEach(images.indices, id: \.self) { index in
                        Image(uiImage: images[index])
                            .resizable()
                            .aspectRatio(1, contentMode: .fit)
                            .frame(maxWidth: .infinity)
                            .clipped()
                    }
                } else {
                    Button {
                        openAppSettings()
                    } label: {
                        ZStack {
                            Rectangle()
                                .fill(Color.Main.backgroundLight)
                                .overlay {
                                    VStack {
                                        Image(systemName: "photo")
                                            .foregroundColor(.Material.tortoiseLight300)
                                            .font(.system(size: 30))
                                        Text("Allow gallery access")
                                            .foregroundColor(.Main.black)
                                            .font(.body3)
                                    }
                                }
                                .frame(height: 100)
                        }
                    }
                }
            }
        }
        .onAppear {
            checkCameraAccess()
            checkGalleryAccess()
        }
    }

    private func checkCameraAccess() {
        let status = AVCaptureDevice.authorizationStatus(for: .video)
        switch status {
        case .authorized:
            isCameraAccessGranted = true

        case .notDetermined:
            AVCaptureDevice.requestAccess(for: .video) { granted in
                DispatchQueue.main.async {
                    self.isCameraAccessGranted = granted
                }
            }

        case .denied, .restricted:
            isCameraAccessGranted = false

        @unknown default:
            isCameraAccessGranted = false
        }
    }

    private func checkGalleryAccess() {
        let status = PHPhotoLibrary.authorizationStatus()
        switch status {
        case .authorized, .limited:
            isGalleryAccessGranted = true
            fetchImages()

        case .notDetermined:
            PHPhotoLibrary.requestAuthorization { status in
                DispatchQueue.main.async {
                    self.isGalleryAccessGranted = status == .authorized
                    if self.isGalleryAccessGranted {
                        self.fetchImages()
                    }
                }
            }

        case .denied, .restricted:
            isGalleryAccessGranted = false

        @unknown default:
            isGalleryAccessGranted = false
        }
    }

    private func fetchImages() {
        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: PHImageManagerMaximumSize,
                contentMode: .aspectFill,
                options: option
            ) { image, _ in
                if let image = image {
                    DispatchQueue.main.async {
                        if let img = scaleAndCropImage(image, toSize: CGSize(width: gridSize, height: gridSize)) {
                            self.images.append(img)
                        }
                    }
                }
            }
        }
    }

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

    func scaleAndCropImage(_ image: UIImage, toSize size: CGSize) -> UIImage? {
        let imageView = UIImageView(frame: CGRect(origin: .zero, size: size))
        imageView.contentMode = .scaleAspectFill
        imageView.image = image
        UIGraphicsBeginImageContextWithOptions(size, false, 0.0)
        guard let context = UIGraphicsGetCurrentContext() else { return nil }
        imageView.layer.render(in: context)
        let result = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        return result
    }
}

class CameraUIView: UIView {
    var previewLayer: AVCaptureVideoPreviewLayer?

    override func layoutSubviews() {
        super.layoutSubviews()
        previewLayer?.frame = bounds
    }
}

struct CameraView: UIViewRepresentable {
    func makeUIView(context _: Context) -> CameraUIView {
        let view = CameraUIView()

        let captureSession = AVCaptureSession()
        guard let captureDevice = AVCaptureDevice.default(for: .video) else { return view }
        guard let input = try? AVCaptureDeviceInput(device: captureDevice) else { return view }
        captureSession.addInput(input)

        let previewLayer = AVCaptureVideoPreviewLayer(session: captureSession)
        previewLayer.videoGravity = .resizeAspectFill
        view.layer.addSublayer(previewLayer)
        view.previewLayer = previewLayer

        captureSession.startRunning()

        return view
    }

    func updateUIView(_ uiView: CameraUIView, context _: Context) {
        // Update the previewLayer frame when the view updates
        uiView.previewLayer?.frame = uiView.bounds
    }
}

// struct AttachmentMediaPickerView: View {
//     @StateObject private var mediaManager = MediaManager()
//
//     var body: some View {
//         ScrollView {
//             LazyVGrid(columns: Array(repeating: .init(.flexible()), count: 3)) {
//                 ForEach(elements) { element in
//                     element
//                 }
//             }
//             .padding(.horizontal, 8)
//         }
//         .padding(.vertical, 8)
//     }
//
//     private var elements: [GridElement] {
//         print("Creating elements")
//         var result: [GridElement] = []
//
//         // camera
//         if let feed = mediaManager.cameraFeed, mediaManager.cameraAccessLevel == .authorized {
//             result.append(GridElement(id: UUID(), type: .cameraFeed, content: feed) {
//                 print("Go to capture???")
//             })
//             print("Added camera feed")
//         } else if mediaManager.cameraAccessLevel == .restricted {
//             result.append(GridElement(id: UUID(), type: .cameraRestricted, content: nil) {
//                 print("Show alert")
//             })
//             print("Added camera restricted")
//         } else {
//             result.append(GridElement(id: UUID(), type: .cameraAskButton, content: nil) {
//                 mediaManager.openAppSettings()
//             })
//             print("Added camera ask button")
//         }
//
//         // photos
//         // if mediaManager.galleryAccessLevel == .restricted {
//         //     result.append(GridElement(id: UUID(), type: .photoRestricted, content: nil))
//         // } else {
//         //     for photo in mediaManager.photos {
//         //         result.append(GridElement(id: UUID(), type: .photo, content: photo))
//         //     }
//         //     if mediaManager.galleryAccessLevel != .authorized {
//         //         result.append(GridElement(id: UUID(), type: .photoAskButton, content: nil))
//         //     }
//         // }
//
//         return result
//     }
// }
//
// private enum GridElementType {
//     case cameraFeed
//     case cameraAskButton
//     case cameraRestricted
//     case photo
//     case photoAskButton
//     case photoRestricted
// }
//
// private struct GridElement: View, Identifiable {
//     let id: UUID
//     let type: GridElementType
//     let content: UIImage?
//     let action: () -> Void
//
//     var body: some View {
//         switch type {
//         case .cameraFeed:
//             image
//                 .resizable()
//                 .aspectRatio(contentMode: .fill)
//                 .frame(width: 100, height: 100)
//                 .clipped()
//
//         case .cameraAskButton:
//             Button {
//                 action()
//             } label: {
//                 RoundedRectangle(cornerRadius: 5)
//                     .stroke(Color.Main.backgroundDark, lineWidth: 2)
//                     .overlay {
//                         Image(systemName: "camera")
//                             .foregroundColor(.Material.tortoiseLight300)
//                             .font(.system(size: 40))
//                     }
//                     .frame(height: 100)
//                 // .resizable()
//                 // .aspectRatio(contentMode: .fill)
//                 // .frame(width: 100, height: 100)
//                 // .clipped()
//             }
//
//         case .photo:
//             image
//                 .resizable()
//                 .aspectRatio(contentMode: .fill)
//                 .frame(width: 100, height: 100)
//                 .clipped()
//
//         case .photoAskButton:
//             Button {
//                 action()
//             } label: {
//                 Image(systemName: "photo.badge.plus")
//                     .resizable()
//                     .aspectRatio(contentMode: .fill)
//                     .frame(width: 100, height: 100)
//                     .clipped()
//             }
//
//         case .photoRestricted, .cameraRestricted:
//             Button {
//                 action()
//             } label: {
//                 Image(systemName: "cross")
//                     .resizable()
//                     .aspectRatio(contentMode: .fill)
//                     .frame(width: 100, height: 100)
//                     .clipped()
//             }
//         }
//     }
//
//     private var image: Image {
//         guard let content = content else {
//             return Image(systemName: "questionmark.square.dashed")
//         }
//         return Image(uiImage: content)
//     }
// }
//
// struct AttachmentMediaPickerView_Previews: PreviewProvider {
//     static var previews: some View {
//         AttachmentMediaPickerView()
//     }
// }