//
//  NCUploadScanDocument.swift
//  Nextcloud
//
//  Created by Marino Faggiana on 28/12/22.
//  Copyright © 2022 Marino Faggiana. All rights reserved.
//
//  Author Marino Faggiana <marino.faggiana@nextcloud.com>
//
//  This program is free software: you can redistribute it and/or modify
//  it under the terms of the GNU General Public License as published by
//  the Free Software Foundation, either version 3 of the License, or
//  (at your option) any later version.
//
//  This program is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU General Public License for more details.
//
//  You should have received a copy of the GNU General Public License
//  along with this program.  If not, see <http://www.gnu.org/licenses/>.
//

import SwiftUI
import NextcloudKit
import Vision
import VisionKit
import Photos
import PDFKit

class NCHostingUploadScanDocumentView: NSObject {

    @objc func makeShipDetailsUI(images: [UIImage], userBaseUrl: NCUserBaseUrl, serverUrl: String) -> UIViewController {

        let uploadScanDocument = NCUploadScanDocument(images: images, userBaseUrl: userBaseUrl, serverUrl: serverUrl)
        let details = UploadScanDocumentView(uploadScanDocument)
        let vc = UIHostingController(rootView: details)
        vc.title = NSLocalizedString("_save_", comment: "")
        return vc
    }
}

// MARK: - Class

class NCUploadScanDocument: ObservableObject {

    var fileName: String = ""
    var userBaseUrl: NCUserBaseUrl
    var serverUrl: String
    var url: URL = Bundle.main.url(forResource: "Reasons to use Nextcloud", withExtension: "pdf")!
    var metadata = tableMetadata()
    var images: [UIImage]
    let fileNameDefault = NSTemporaryDirectory() + "scandocument.pdf"

    init(images: [UIImage], userBaseUrl: NCUserBaseUrl, serverUrl: String) {
        self.images = images
        self.userBaseUrl = userBaseUrl
        self.serverUrl = serverUrl
    }

    func save(completion: @escaping (_ openConflictViewController: Bool) -> Void) {

        guard !fileName.isEmpty else { return }

        let ext = (fileName as NSString).pathExtension.uppercased()
        var fileNameSave = ""

        if ext.isEmpty {
            fileNameSave = fileName + ".pdf"
        } else {
            fileNameSave = (fileName as NSString).deletingPathExtension + ".pdf"
        }

        // Create metadata for upload
        metadata = NCManageDatabase.shared.createMetadata(account: userBaseUrl.account,
                                                          user: userBaseUrl.user,
                                                          userId: userBaseUrl.userId,
                                                          fileName: fileNameSave,
                                                          fileNameView: fileNameSave,
                                                          ocId: UUID().uuidString,
                                                          serverUrl: serverUrl,
                                                          urlBase: userBaseUrl.urlBase,
                                                          url: "",
                                                          contentType: "")

        metadata.session = NCNetworking.shared.sessionIdentifierBackground
        metadata.sessionSelector = NCGlobal.shared.selectorUploadFile
        metadata.status = NCGlobal.shared.metadataStatusWaitUpload

        if NCManageDatabase.shared.getMetadataConflict(account: userBaseUrl.account, serverUrl: serverUrl, fileNameView: fileNameSave) != nil {
            completion(true)
        } else {
            uploadMetadata()
            completion(false)
        }
    }

    func uploadMetadata() {

        guard let fileNameGenerateExport = CCUtility.getDirectoryProviderStorageOcId(metadata.ocId, fileNameView: metadata.fileNameView) else { return }
        NCUtilityFileSystem.shared.copyFile(atPath: fileNameDefault, toPath: fileNameGenerateExport)
        metadata.size = NCUtilityFileSystem.shared.getFileSize(filePath: fileNameGenerateExport)
        NCNetworkingProcessUpload.shared.createProcessUploads(metadatas: [metadata], completion: { _ in })
    }

    func createPDFPreview(quality: Double) -> Data {

        let pdfData = NSMutableData()

        UIGraphicsBeginPDFContextToData(pdfData, CGRect.zero, nil)

        if var image = images.first {
            image = changeCompressionImage(image, quality: quality)
            let bounds = CGRect(x: 0, y: 0, width: image.size.width, height: image.size.height)
            UIGraphicsBeginPDFPageWithInfo(bounds, nil)
            image.draw(in: bounds)
        }

        UIGraphicsEndPDFContext()

        return pdfData as Data
    }

    func createPDF(password: String = "", isTextRecognition: Bool = false, quality: Double) {

        guard !images.isEmpty else { return }
        let pdfData = NSMutableData()

        if password.isEmpty {
            UIGraphicsBeginPDFContextToData(pdfData, CGRect.zero, nil)
        } else {
            for char in password.unicodeScalars {
                if !char.isASCII {
                    NCActivityIndicator.shared.stop()
                    let error = NKError(errorCode: NCGlobal.shared.errorForbidden, errorDescription: "_password_ascii_")
                    NCContentPresenter.shared.showError(error: error)
                    return
                }
            }
            let info: [AnyHashable: Any] = [kCGPDFContextUserPassword as String: password, kCGPDFContextOwnerPassword as String: password]
            UIGraphicsBeginPDFContextToData(pdfData, CGRect.zero, info)
        }

        for var image in images {

            image = changeCompressionImage(image, quality: quality)
            let bounds = CGRect(x: 0, y: 0, width: image.size.width, height: image.size.height)
            if isTextRecognition {
                UIGraphicsBeginPDFPageWithInfo(bounds, nil)
                image.draw(in: bounds)
            } else {
                UIGraphicsBeginPDFPageWithInfo(bounds, nil)
                image.draw(in: bounds)
            }
        }

        UIGraphicsEndPDFContext()

        do {
            url = URL(fileURLWithPath: fileNameDefault)
            try pdfData.write(to: url, options: .atomic)
        } catch {
            print("error catched")
        }
    }

    func changeCompressionImage(_ image: UIImage, quality: Double) -> UIImage {

        var compressionQuality: CGFloat = 0.0
        var baseHeight: Float = 595.2    // A4
        var baseWidth: Float = 841.8     // A4

        switch quality {
        case 0:
            baseHeight *= 1
            baseWidth *= 1
            compressionQuality = 0.2
        case 1:
            baseHeight *= 2
            baseWidth *= 2
            compressionQuality = 0.3
        case 2:
            baseHeight *= 3
            baseWidth *= 3
            compressionQuality = 0.4
        case 3:
            baseHeight *= 4
            baseWidth *= 4
            compressionQuality = 0.5
        default:
            break
        }

        var newHeight = Float(image.size.height)
        var newWidth = Float(image.size.width)
        var imgRatio: Float = newWidth / newHeight
        let baseRatio: Float = baseWidth / baseHeight

        if newHeight > baseHeight || newWidth > baseWidth {
            if imgRatio < baseRatio {
                imgRatio = baseHeight / newHeight
                newWidth = imgRatio * newWidth
                newHeight = baseHeight
            } else if imgRatio > baseRatio {
                imgRatio = baseWidth / newWidth
                newHeight = imgRatio * newHeight
                newWidth = baseWidth
            } else {
                newHeight = baseHeight
                newWidth = baseWidth
            }
        }

        let rect = CGRect(x: 0.0, y: 0.0, width: CGFloat(newWidth), height: CGFloat(newHeight))
        UIGraphicsBeginImageContext(rect.size)
        image.draw(in: rect)
        let img = UIGraphicsGetImageFromCurrentImageContext()
        let imageData = img?.jpegData(compressionQuality: CGFloat(compressionQuality))
        UIGraphicsEndImageContext()
        if let imageData = imageData, let image = UIImage(data: imageData) {
            return image
        }
        return image
    }
}

// MARK: - Delegate

extension NCUploadScanDocument: NCSelectDelegate {

    func dismissSelect(serverUrl: String?, metadata: tableMetadata?, type: String, items: [Any], overwrite: Bool, copy: Bool, move: Bool) {

        if let serverUrl = serverUrl {

            CCUtility.setDirectoryScanDocument(serverUrl)
            self.serverUrl = serverUrl
        }
    }
}

extension NCUploadScanDocument: NCCreateFormUploadConflictDelegate {

    func dismissCreateFormUploadConflict(metadatas: [tableMetadata]?) {

        if metadatas == nil { return }
        uploadMetadata()
        NotificationCenter.default.postOnMainThread(name: NCGlobal.shared.notificationCenterDismissScanDocument)
    }
}

// MARK: - View

struct UploadScanDocumentView: View {

    @State var quality = CCUtility.getQualityScanDocument()
    @State var password: String = ""
    @State var isSecuredPassword: Bool = true
    @State var isTextRecognition: Bool = CCUtility.getTextRecognitionStatus()
    @State var isPresentedSelect = false
    @State var isPresentedUploadConflict = false

    var metadatasConflict: [tableMetadata] = []

    @ObservedObject var uploadScanDocument: NCUploadScanDocument
    @Environment(\.presentationMode) var presentationMode

    init(_ uploadScanDocument: NCUploadScanDocument) {
        self.uploadScanDocument = uploadScanDocument
    }

    var body: some View {

        GeometryReader { geo in
            List {
                Section(header: Text(NSLocalizedString("_file_creation_", comment: ""))) {
                    HStack {
                        Label {
                            if NCUtilityFileSystem.shared.getHomeServer(urlBase: uploadScanDocument.userBaseUrl.urlBase, userId: uploadScanDocument.userBaseUrl.userId) == uploadScanDocument.serverUrl {
                                Text("/")
                                    .frame(maxWidth: .infinity, alignment: .trailing)
                            } else {
                                Text((uploadScanDocument.serverUrl as NSString).lastPathComponent)
                                    .frame(maxWidth: .infinity, alignment: .trailing)
                            }
                        } icon: {
                            Image("folder")
                                .renderingMode(.template)
                                .resizable()
                                .scaledToFit()
                                .foregroundColor(Color(NCBrandColor.shared.brand))
                        }
                    }
                    .contentShape(Rectangle())
                    .onTapGesture {
                        isPresentedSelect = true
                    }
                    .complexModifier { view in
                        if #available(iOS 16, *) {
                            view.alignmentGuide(.listRowSeparatorLeading) { _ in
                                return 0
                            }
                        }
                    }

                    HStack {
                        Text(NSLocalizedString("_filename_", comment: ""))
                        TextField(NSLocalizedString("_enter_filename_", comment: ""), text: $uploadScanDocument.fileName)
                            .multilineTextAlignment(.trailing)
                    }

                    HStack {
                        Group {
                            Text(NSLocalizedString("_password_", comment: ""))
                            if isSecuredPassword {
                                SecureField(NSLocalizedString("_enter_password_", comment: ""), text: $password)
                                    .multilineTextAlignment(.trailing)
                            } else {
                                TextField(NSLocalizedString("_enter_password_", comment: ""), text: $password)
                                    .multilineTextAlignment(.trailing)
                            }
                        }
                        Button(action: {
                            isSecuredPassword.toggle()
                        }) {
                            Image(systemName: self.isSecuredPassword ? "eye.slash" : "eye")
                                .accentColor(.gray)
                        }
                    }

                    HStack {
                        Toggle(NSLocalizedString("_text_recognition_", comment: ""), isOn: $isTextRecognition)
                            .toggleStyle(SwitchToggleStyle(tint: Color(NCBrandColor.shared.brand)))
                            .onChange(of: isTextRecognition) { newValue in
                                CCUtility.setTextRecognitionStatus(newValue)
                            }
                    }
                }

                Section(header: Text(NSLocalizedString("_quality_image_title_", comment: ""))) {

                    VStack {
                        Slider(value: $quality, in: 0...3, step: 1, onEditingChanged: { touch in
                            if !touch {
                                CCUtility.setQualityScanDocument(quality)
                                // uploadScanDocument.createPDF(password: password, isTextRecognition: isTextRecognition, quality: quality)
                            }
                        })
                        .accentColor(Color(NCBrandColor.shared.brand))
                    }
                    PDFKitRepresentedView(quality: $quality, uploadScanDocument: uploadScanDocument)
                        .frame(maxWidth: .infinity, minHeight: geo.size.height / 2.7)
                }.complexModifier { view in
                    if #available(iOS 15, *) {
                        view.listRowSeparator(.hidden)
                    }
                }

                Button(NSLocalizedString("_save_", comment: "")) {
                    // presentationMode.wrappedValue.dismiss()
                    uploadScanDocument.save { openConflictViewController in
                        if openConflictViewController {
                            isPresentedUploadConflict = true
                        } else {
                            NotificationCenter.default.postOnMainThread(name: NCGlobal.shared.notificationCenterDismissScanDocument)
                        }
                    }
                }
                .buttonStyle(ButtonUploadScanDocumenStyle(disabled: uploadScanDocument.fileName.isEmpty))
                .frame(maxWidth: .infinity, alignment: .center)
                .listRowBackground(Color(UIColor.systemGroupedBackground))
            }
        }
        .background(Color(UIColor.systemGroupedBackground))
        .sheet(isPresented: $isPresentedSelect) {
            NCSelectRepresentedView(uploadScanDocument: uploadScanDocument)
        }
        .sheet(isPresented: $isPresentedUploadConflict) {
            NCUploadConflictRepresentedView(uploadScanDocument: uploadScanDocument)
        }
    }
}

struct ButtonUploadScanDocumenStyle: ButtonStyle {
    var disabled = false
    func makeBody(configuration: Configuration) -> some View {
        configuration.label
            .padding(.horizontal, 40)
            .padding(.vertical, 10)
            .background(disabled ? Color(UIColor.systemGray4) : Color(NCBrandColor.shared.brand))
            .foregroundColor(.white)
            .clipShape(Capsule())
    }
}

// MARK: - UIViewControllerRepresentable

struct NCSelectRepresentedView: UIViewControllerRepresentable {

    typealias UIViewControllerType = UINavigationController
    @ObservedObject var uploadScanDocument: NCUploadScanDocument

    func makeUIViewController(context: Context) -> UINavigationController {

        let storyboard = UIStoryboard(name: "NCSelect", bundle: nil)
        let navigationController = storyboard.instantiateInitialViewController() as? UINavigationController
        let viewController = navigationController?.topViewController as? NCSelect

        viewController?.delegate = uploadScanDocument
        viewController?.typeOfCommandView = .selectCreateFolder
        viewController?.includeDirectoryE2EEncryption = true

        return navigationController!
    }

    func updateUIViewController(_ uiViewController: UINavigationController, context: Context) {
    }
}

struct NCUploadConflictRepresentedView: UIViewControllerRepresentable {

    typealias UIViewControllerType = NCCreateFormUploadConflict
    @ObservedObject var uploadScanDocument: NCUploadScanDocument

    func makeUIViewController(context: Context) -> NCCreateFormUploadConflict {

        let storyboard = UIStoryboard(name: "NCCreateFormUploadConflict", bundle: nil)
        let viewController = storyboard.instantiateInitialViewController() as? NCCreateFormUploadConflict

        viewController?.delegate = uploadScanDocument
        viewController?.textLabelDetailNewFile = NSLocalizedString("_now_", comment: "")
        viewController?.serverUrl = uploadScanDocument.serverUrl
        viewController?.metadatasUploadInConflict = [uploadScanDocument.metadata]

        return viewController!
    }

    func updateUIViewController(_ uiViewController: NCCreateFormUploadConflict, context: Context) {
    }
}

struct PDFKitRepresentedView: UIViewRepresentable {

    typealias UIView = PDFView
    @Binding var quality: Double
    @ObservedObject var uploadScanDocument: NCUploadScanDocument
    let fileNameDefault = NSTemporaryDirectory() + "scandocument.pdf"

    func makeUIView(context: UIViewRepresentableContext<PDFKitRepresentedView>) -> PDFKitRepresentedView.UIViewType {
        let pdfView = PDFView()
        pdfView.autoScales = true
        pdfView.backgroundColor = .clear
        pdfView.displayMode = .singlePage
        pdfView.displayDirection = .vertical
        return pdfView
    }

    func updateUIView(_ uiView: UIView, context: UIViewRepresentableContext<PDFKitRepresentedView>) {
        let data = uploadScanDocument.createPDFPreview(quality: quality)
        uiView.document = PDFDocument(data: data)
    }
}

// MARK: - Preview

struct UploadScanDocumentView_Previews: PreviewProvider {
    static var previews: some View {
        if let appDelegate = UIApplication.shared.delegate as? AppDelegate {
            let uploadScanDocument = NCUploadScanDocument(images: [], userBaseUrl: appDelegate, serverUrl: "ABCD")
            UploadScanDocumentView(uploadScanDocument)
        }
    }
}