//
/*
 * Copyright (c) 2024 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

/// Helper  class for making our SwiftUI view available to ObjectiveC
@objcMembers class RoomFederationDecisionSheet: NSObject {
    private var decisionView: RoomFederationDecisionView?
    @Published var theme: Theme
    
    override init() {
        theme = ThemeService.shared().theme
    }
    
    func makeViewController(room: MXRoom, roomAvatarImage: UIImage) -> UIViewController {
        registerThemeServiceDidChangeThemeNotification()
        self.decisionView = RoomFederationDecisionView(theme: Binding(get: {
            return self.theme
        }, set: { newTheme in
            self.theme = newTheme
        }), room: room, roomAvatarImage: roomAvatarImage)
        return UIHostingController(rootView: decisionView)
    }
    
    private func registerThemeServiceDidChangeThemeNotification() {
        NotificationCenter.default.addObserver(self, selector: #selector(themeDidChange), name: .themeServiceDidChangeTheme, object: nil)
    }
  
    @objc private func themeDidChange() {
        self.theme = ThemeService.shared().theme
    }
    
}

// bwi: #5304
struct RoomFederationDecisionView: View {
    @Environment(\.dismiss) var dismissView
    @State var isUpdatingServerACLs: Bool = false
    @Binding var theme: Theme
    @State var showAlert: Bool = false
    
    // show error alert when value is false
    @State var showSuccessAlert: Bool = false
    
    var room: MXRoom
    @State var pendingRequest: MXHTTPOperation?
    
    var roomAvatarImage: UIImage
    let imageStackScale = 0.30
    let imageStackShift = 5.0
    let outerLineWith = 5.0
    let innerLineWith = 1.0
    let spacing = 16.0
    
    
    var body: some View {
        GeometryReader { geo in
            ScrollView(.vertical) {
                VStack(spacing: spacing) {
                    VStack(spacing: spacing) {
                        Spacer()
                        // Federation image with room avatar
                        ZStack(alignment: .center) {
                            Circle()
                                .fill(Color(theme.colors.quinaryContent))
                                .padding(outerLineWith)
                                .offset(x:((getImageSize(width: geo.size.width, height: geo.size.height) * imageStackScale) / imageStackShift))
                            Image(uiImage: roomAvatarImage)
                                .resizable()
                                .clipShape(Circle())
                                .padding(innerLineWith)
                                .background(Color(theme.colors.quinaryContent))
                                .clipShape(Circle())
                                .padding(outerLineWith)
                                .background(Color(theme.colors.background))
                                .clipShape(Circle())
                                .offset(x:-((getImageSize(width: geo.size.width, height: geo.size.height) * imageStackScale) / imageStackShift))
                        }
                        .frame(width: getImageSize(width: geo.size.width, height: geo.size.height) * imageStackScale, height: getImageSize(width: geo.size.width, height: geo.size.height) * imageStackScale)
                        
                        // Federation info text
                        textStack
                    }
                    
                    if isUpdatingServerACLs {
                        ProgressView()
                    }
                    
                    // Federation actions
                    buttonStack
                }
                .frame(minHeight: geo.size.height)
            }
            .interactiveDismissDisabled()
            .frame(width: geo.size.width, height: geo.size.height)
            .background(Color(theme.colors.background))
            .alert(isPresented: $showAlert) {
                if (showSuccessAlert) {
                    return Alert(title: Text(BWIL10n.roomAdminFederationDecisionSetFederationSuccessAlertTitle), message: nil, dismissButton: .default(Text(BWIL10n.roomAdminFederationDecisionSetFederationAlertOkButton), action: {
                        closeView()
                    }))
                } else {
                    return Alert(title: Text(BWIL10n.roomAdminFederationDecisionSetFederationErrorAlertTitle), message: Text(BWIL10n.roomAdminFederationDecisionSetFederationErrorAlertText), dismissButton: .default(Text(BWIL10n.roomAdminFederationDecisionSetFederationAlertOkButton), action: {
                        closeView()
                    }))
                }
            }
        }
    }
    
    func getImageSize(width: CGFloat, height: CGFloat) -> CGFloat {
        return (width > height ? height : width)
    }
    
    
    var textStack: some View {
        LazyVStack(spacing: spacing) {
            Text(BWIL10n.roomAdminFederationDecisionSheetTitle(room.displayName ?? ""))
                .font(.system(size: 24).bold())
                .multilineTextAlignment(.center)
                .lineLimit(nil)
                .foregroundColor(Color(theme.colors.primaryContent))
            Text(BWIL10n.roomAdminFederationDecisionSheetText)
                .font(Font(theme.fonts.subheadline))
                .multilineTextAlignment(.center)
                .lineLimit(nil)
                .foregroundColor(Color(theme.colors.secondaryContent))
        }
        .padding(spacing)
    }
    
    
    var buttonStack: some View {
        VStack(spacing: spacing) {
            Spacer()
            Button {
                setServerACL(isFederated: true)
            } label: {
                Text(BWIL10n.roomAdminFederationDecisionSheetActivateFederationButton)
            }
            .buttonStyle(SecondaryActionButtonStyle())
            .accessibilityIdentifier("federationDecisionSheetActivateFederationButton")
            .disabled(isUpdatingServerACLs)
            Button {
                setServerACL(isFederated: false)
            } label: {
                Text(BWIL10n.roomAdminFederationDecisionSheetDeactivateFederationButton)
            }
            .buttonStyle(PrimaryActionButtonStyle())
            .accessibilityIdentifier("federationDecisionSheetDeactivateFederationButton")
            .disabled(isUpdatingServerACLs)
        }
        .padding(spacing)
    }
    
    
    func setServerACL(isFederated: Bool) {
        let content: [String:Any] = room.createServerACL(isFederated: isFederated)
        isUpdatingServerACLs = true
        // #5383 set alias
        room.setAliasIfNeeded(roomName: room.displayName)
        pendingRequest = room.sendStateEvent(MXEventType.roomServerACL, content: content, stateKey: "") { response in
            isUpdatingServerACLs = false
            // #5578 show alert on success if room is federated
            if (response.isSuccess) {
                // bwi #5393 tracking, use the buildSettig here to avoid admin calculation if not necessary
                if BWIBuildSettings.shared.bwiMatomoEnabled {
                    BWIAnalyticsHelper().getRoomAdminCount(room: room) { (adminCount) in
                        BWIAnalytics.sharedTracker.trackEvent(category: "Federation", action: "ShowSettingFederateRoom", name: isFederated ? "accept" : "decline", number: NSNumber(value: adminCount))
                    }
                }

                if (isFederated) {
                    showSuccessAlert = true
                    showAlert = true
                } else {
                    closeView()
                }
            } else {
                // show error alert
                showSuccessAlert = false
                showAlert = true
            }
        }
        
    }
    
    func closeView() {
        if let pendingRequest = pendingRequest {
            pendingRequest.cancel()
        }
        dismissView()
    }

}