//
//  SettingsView.swift
//  Feels
//
//  Created by Trey Tartt on 1/8/22.
//

import SwiftUI

struct SettingsView: View {
    @Environment(\.dismiss) var dismiss
    
    @AppStorage("notificationDate") private var notificationDate = Date() {
        didSet {
            if self.showReminder {
                LocalNotification.scheduleReminder(atTime: self.notificationDate)
            }
        }
    }
    
    @AppStorage("showReminder") private var showReminder: Bool = false
    
    var body: some View {
        ZStack {
            Color(UIColor.secondarySystemBackground)
            
            VStack {
                closeButtonView
                    .padding()
                notificationCell
                randomShitCell
                addTestDataCell
                clearDB
                whyBackgroundMode
                Spacer()
            }
            .padding()
        }
    }
    
    private var closeButtonView: some View {
        HStack{
            Spacer()
            Button(action: {
                dismiss()
            }, label: {
                Text("Exit")
                    .font(.body)
                    .foregroundColor(Color(UIColor.systemBlue))
            })
        }
    }
    
    private var notificationCell: some View {
        ZStack {
            Color(UIColor.systemBackground)
            VStack {
                Toggle("Would you like to be reminded?", isOn: $showReminder)
                    .onChange(of: showReminder, perform: { value in
                        self.maybeNotificaiotns(areEnabled: value)
                    })
                    .padding()
                DatePicker("", selection: $notificationDate, displayedComponents: .hourAndMinute)
                    .onChange(of: notificationDate, perform: { value in
                        self.updateNotificationTimes(toDate: value)
                    })
                    .disabled(showReminder == false)
                    .padding()
            }
        }
        .fixedSize(horizontal: false, vertical: true)
        .clipShape(RoundedRectangle(cornerRadius: 25, style: .continuous))
    }
    
    private var randomShitCell: some View {
        ZStack {
            Color(UIColor.systemBackground)
            VStack {
                Button(action: {
                    
                }, label: {
                    Text("Special thanks to")
                })
                    .padding()
            }
        }
        .fixedSize(horizontal: false, vertical: true)
        .clipShape(RoundedRectangle(cornerRadius: 25, style: .continuous))
    }
    
    private var addTestDataCell: some View {
        ZStack {
            Color(UIColor.systemBackground)
            Button(action: {
                PersistenceController.shared.populateTestData()
            }, label: {
                Text("Add test data")
            })
                .padding()
        }
        .fixedSize(horizontal: false, vertical: true)
        .clipShape(RoundedRectangle(cornerRadius: 25, style: .continuous))
    }
    
    private var clearDB: some View {
        ZStack {
            Color(UIColor.systemBackground)
            Button(action: {
                PersistenceController.shared.clearDB()
            }, label: {
                Text("Clear DB")
            })
                .padding()
        }
        .fixedSize(horizontal: false, vertical: true)
        .clipShape(RoundedRectangle(cornerRadius: 25, style: .continuous))
    }
    
    private var whyBackgroundMode: some View {
        ZStack {
            Color(UIColor.systemBackground)
            Text("we do bg mode b/c we can")
                .padding()
        }
        .fixedSize(horizontal: false, vertical: true)
        .clipShape(RoundedRectangle(cornerRadius: 25, style: .continuous))
    }
    
    private func updateNotificationTimes(toDate date: Date) {
        LocalNotification.removeNotificaiton()
        
        LocalNotification.scheduleReminder(atTime: date)
    }
    
    private func maybeNotificaiotns(areEnabled: Bool) {
        if areEnabled {
            LocalNotification.testIfEnabled(completion: { result in
                switch result{
                case .success(_):
                    LocalNotification.scheduleReminder(atTime: self.notificationDate)
                case .failure(let error):
                    print(error)
                    // show error
                    break
                }
            })
        } else {
            LocalNotification.removeNotificaiton()
        }
    }
}

struct SettingsView_Previews: PreviewProvider {
    static var previews: some View {
        SettingsView()
        
        SettingsView()
            .preferredColorScheme(.dark)
    }
}