//
//  ContentView.swift
//  sdsz74
//
//  Created by yunli on 2023/5/18.
//

import SwiftUI

struct ContentView: View {
    @State private var examCount = 0
    @State private var messageCount = 0
    @State private var isLoggedIn = 0
    var body: some View {
        TabView{
            NavigationView {
                NavigationLink(destination: examListView(count:$examCount)) {
                    Text("共 \(examCount) 场考试")
                }
                .navigationBarTitle("74 桌")
            }
                .tabItem({Image(systemName: "chart.bar.fill")
                    Text("成绩分析")})
            NavigationView {
                List{
                    NavigationLink(destination: messageView(count:$messageCount)) {
                        Text("消息")
                            .badge(messageCount)
                    }
                }
                .navigationBarTitle("数字校园")
            }
                .tabItem({Image(systemName: "graduationcap")
                    Text("数字校园")})
            NavigationView{
                if isLoggedIn != 0{
                    accountView(isLoggedIn: $isLoggedIn)
                    .navigationBarTitle("账号")
                }
                else{
                    loginView(isLoggedIn:$isLoggedIn)
                    .navigationBarTitle("登录")
                }
            }
                .tabItem({Image(systemName: "person")
                    Text("账号")})
            
        }
    }
}

extension View {
    func hideKeyboard() {
        UIApplication.shared.sendAction(
            #selector(UIResponder.resignFirstResponder),
            to: nil,
            from: nil,
            for: nil
        )
    }
}

func doLogin(status:inout Int)->Void{
    status=1
}

struct loginView:View{
    @State var username: String = ""
    @State var password: String = ""
    @FocusState private var isFocused:Bool
    @Binding var isLoggedIn: Int
    var body: some View {
        VStack{
            Form {
                Section{
                    TextField(text: $username, prompt: Text("数字校园号")) {
                        Text("Username")
                    }.focused($isFocused)
                    SecureField(text: $password, prompt: Text("密码")) {
                        Text("Password")
                    }.focused($isFocused)
                }.onTapGesture  {
                    isFocused=false
                }
                Section{
                    HStack{
                        Spacer()
                        Button(action:{doLogin(status: &isLoggedIn)}){
                            VStack{
                                Text("登录")
                            }
                        }.font(.title3)
                        Spacer()
                    }
                }
            }
            Spacer()
        }
    }
}

struct accountView:View{
    @State var username: String = ""
    @State var password: String = ""
    @FocusState private var isFocused:Bool
    @Binding var isLoggedIn: Int
    var body: some View {
        VStack{
            Form {
                Section(header:Text("hi")){
                    Text("一些")
                    Text("一些")
                    Text("东西")
                }
                Section{
                    Button(action:{isLoggedIn=0}){
                        VStack{
                            Text("退出").foregroundColor(.red)
                        }
                    }
                }
            }
            Spacer()
        }
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}