/*
 * Copyright (c) 2022 BWI GmbH
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import SwiftUI

@available(iOS 14.0, *)
/// The splash screen shown at the beginning of the onboarding flow.
struct OnboardingBwiSplashScreen: View {

    // MARK: - Properties
    
    // MARK: Private
    
    @Environment(\.theme) private var theme
    @Environment(\.layoutDirection) private var layoutDirection
    
    /// The dimensions of the stack with the action buttons and page indicator.
    @State private var overlayFrame: CGRect = .zero
    @State private var showServerMaintananceAlert = false
    @State private var showServerMaintananceDefaultAlert = false
    @State private var showInvalidAppVersionAlert = false
    @State private var isFetchingDowntime = false

    // MARK: Public
    
    @ObservedObject var viewModel: OnboardingBwiSplashScreenViewModel.Context
    
    /// The main action buttons.
    var startButton: some View {
        Button(action: startButtonAction) {
            if isFetchingDowntime {
                ProgressView()
            } else {
                Text(BWIL10n.splashScreenStart)
                    .font(theme.fonts.body.bold())
                    .frame(minWidth: 0, maxWidth: .infinity, minHeight: 32)
            }
        }
            .foregroundColor(.white)
            .background(theme.colors.accent)
            .cornerRadius(5)
            .padding([.leading, .trailing], 20)
    }
    
    var footer: some View {
        Image("powered_by_BWI_blk")
            .resizable()
            .aspectRatio(contentMode: .fit)
            .frame(width: 140, alignment: .center)
    }
    
    var body: some View {
        ZStack {
            VStack(spacing: 30) {
                startButton
                    .padding()
                Spacer()
                footer
                    .padding()
            }
        }
        .navigationTitle("")
        .navigationBarHidden(true)
        .alert(isPresented: $showServerMaintananceAlert) {
            Alert(title: Text(BWIL10n.downtimeTitle),
                  message: Text(ServerDowntimeDefaultService().downtimeText()),
                  dismissButton: .destructive(Text(BWIL10n.downtimeAlertDismissButton)) {
                viewModel.send(viewAction: .login)
            })
        }
        .alert(isPresented: $showServerMaintananceDefaultAlert) {
            Alert(title: Text(BWIL10n.downtimeTitle),
                  message: Text(BWIL10n.downtimeDefaultMessage),
                  dismissButton: .destructive(Text(BWIL10n.downtimeAlertDismissButton)) {
                viewModel.send(viewAction: .login)
            })
        }
        .alert(isPresented: $showInvalidAppVersionAlert) {
            Alert(title: Text(BWIL10n.bwiOutdatedVersionWarningTitle),
                  message: Text(BWIL10n.bwiOutdatedVersionWarningMessage(AppInfo.current.displayName)),
                  dismissButton: .destructive(Text(BWIL10n.bwiOutdatedVersionAppstoreButton), action: {
                let iTunesLink = "itms://itunes.apple.com/app/BwMessenger/id1518548153?mt=8"
                UIApplication.shared.open(URL(string: iTunesLink)!, options: [:], completionHandler: nil)
            }))
        }
    }
    
    private func startButtonAction() {
//        let service = ServerDowntimeDefaultService()
//        if service.isDowntimePresentable() /*&& service.isDowntimeNow()*/ {
//            showServerMaintananceAlert = true
//        } else {
            viewModel.send(viewAction: .login)
//        }

//      isFetchingDowntime = true   // show progresview
//        
//        let service = ServerDowntimeDefaultService()
//        service.fetchDowntimesWithDirectRequest { success in
//            self.isFetchingDowntime = false   // hide progressview
//            if success {
//                if service.isDowntimePresentable() && service.isDowntimeNow() {
//                    showServerMaintananceAlert = true
//                } else {
//                    viewModel.send(viewAction: .login)
//                }
//            } else {
//                showServerMaintananceDefaultAlert = true
//            }
//        }
    }
}

// MARK: - Previews

@available(iOS 14.0, *)
struct OnboardingBwiSplashScreen_Previews: PreviewProvider {
    static let stateRenderer = MockOnboardingBwiSplashScreenScreenState.stateRenderer
    static var previews: some View {
        stateRenderer.screenGroup()
    }
}