// 
// Copyright 2022 New Vector Ltd
//
// 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

struct UserSessionsOverview: View {

    // MARK: - Properties
    
    // MARK: Private
    
    @Environment(\.theme) private var theme: ThemeSwiftUI
    
    // MARK: Public
    
    @ObservedObject var viewModel: UserSessionsOverviewViewModel.Context
    
    var body: some View {
        ScrollView {
            
            // Security recommendations section
            if viewModel.viewState.unverifiedSessionsViewData.isEmpty == false || viewModel.viewState.inactiveSessionsViewData.isEmpty == false {
                
                // TODO:
            }
            
            // Current session section
            if let currentSessionViewData = viewModel.viewState.currentSessionViewData {
                // TODO:
            }
            
            // Other sessions section
            if viewModel.viewState.otherSessionsViewData.isEmpty == false {
                
                VStack() {
                    
                    // Section header
                    VStack(alignment: .leading) {
                        Text(VectorL10n.userSessionsOverviewOtherSessionsSectionTitle)
                            .font(theme.fonts.footnote)
                            .foregroundColor(theme.colors.secondaryContent)
                            .padding(.bottom, 10)
                        
                        Text(VectorL10n.userSessionsOverviewOtherSessionsSectionInfo)
                            .font(theme.fonts.footnote)
                            .foregroundColor(theme.colors.secondaryContent)
                            .padding(.bottom, 11)
                    }
                    .padding(.horizontal, 16)
                    
                    // Device list
                    VStack(spacing: 16) {
                        ForEach(viewModel.viewState.otherSessionsViewData) { viewData in
                            UserSessionListItem(viewData: viewData, onBackgroundTap: { sessionId in
                                viewModel.send(viewAction: .tapUserSession(sessionId))
                            })
                        }
                    }
                    .padding(.vertical, 16)
                    .background(theme.colors.background)
                }
            }
        }
        .background(theme.colors.system.ignoresSafeArea())
        .frame(maxHeight: .infinity)
        .navigationTitle(VectorL10n.userSessionsOverviewTitle)
        .activityIndicator(show: viewModel.viewState.showLoadingIndicator)
        .onAppear() {
            viewModel.send(viewAction: .viewAppeared)
        }
    }
}

// MARK: - Previews

struct UserSessionsOverview_Previews: PreviewProvider {
    static let stateRenderer = MockUserSessionsOverviewScreenState.stateRenderer
    static var previews: some View {
        stateRenderer.screenGroup()
    }
}