/**
 * TrackerMap
 * Copyright (C) 2021-2022  Iván Ávalos <avalos@disroot.org>, Henoch Ojeda <imhenoch@protonmail.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */
import SwiftUI
import shared

class SessionState: ObservableObject {
    @Published var loggedIn = false
}

struct RootView: View {
    @StateObject private var rootViewModel = RootViewModel()
    @State private var username = ""
    @State private var password = ""
    @State private var server: String
    
    init() {
        server = UserDefaults.standard.string(forKey: "server-url")
        ?? NSLocalizedString("app-server-url", comment: "")
    }
    
    var body: some View {
        Group {
            switch rootViewModel.loginState {
            case is SessionController.LoginStateLoading:
                LoadingView()
            case is SessionController.LoginStateSuccess:
                UnitsView()
            default:
                LoginContentView(username: $username,
                                 password: $password,
                                 server: $server,
                                 onLogin: rootViewModel.login)
            }
        }.environmentObject(rootViewModel)
    }
}

struct LoginContentView: View {
    @Binding var username: String
    @Binding var password: String
    @Binding var server: String
    
    let onLogin: (String, String, String) -> Void
    
	var body: some View {
        VStack {
            Spacer()
            LoginTitleView()
            
            Spacer()
            LoginForm(username: $username,
                      password: $password,
                      server: $server)
            
            Button(action: {
                self.onLogin(username, password, server)
            }) {
                Text("login")
                    .font(.system(size: 18))
                    .bold()
            }
            .padding([.top, .bottom], 30)
            
            Spacer()
        }
        .padding()
	}
}

// Source: https://github.com/niochat/nio

struct LoginTitleView: View {
    var body: some View {
        return VStack {
            Text("app-name")
                .font(.title)
                .bold()
        }
    }
}

struct LoginForm: View {
    @Binding var username: String
    @Binding var password: String
    @Binding var server: String

    var body: some View {
        VStack {
            FormTextField(title: "username", text: $username)

            FormTextField(title: "password", text: $password, isSecure: true)

          #if os(macOS)
            FormTextField(title: "server-url", text: $server)
                .visible(false)
          #else
            FormTextField(title: "server-url", text: $server, keyboardType: .URL)
                .visible(false)
          #endif
        }
    }
}

private struct FormTextField: View {
    @Environment(\.colorScheme) private var colorScheme

    let title: LocalizedStringKey
    @Binding var text: String
    var onEditingChanged: ((Bool) -> Void)?

  #if os(macOS)
  #else
    var keyboardType: UIKeyboardType = .default
  #endif

    var isSecure = false

    var body: some View {
        ZStack {
            Capsule(style: .continuous)
                .foregroundColor(colorScheme == .light
                                 ? Color(#colorLiteral(red: 0.9395676295, green: 0.9395676295, blue: 0.9395676295, alpha: 1))
                                 : Color(#colorLiteral(red: 0.2293992357, green: 0.2293992357, blue: 0.2293992357, alpha: 1)))
                .frame(height: 50)
            if isSecure {
                SecureField(title, text: $text)
                    .padding()
                    .textContentType(.password)
            } else {
              #if os(macOS)
                TextField(title, text: $text, onEditingChanged: onEditingChanged ?? { _ in })
                    .padding()
                    .autocapitalization(.none)
                    .disableAutocorrection(true)
              #else
                TextField(title, text: $text, onEditingChanged: onEditingChanged ?? { _ in })
                    .padding()
                    .autocapitalization(.none)
                    .disableAutocorrection(true)
                    .keyboardType(keyboardType)
              #endif
            }
        }
        .padding(.horizontal)
        .frame(maxWidth: 400)
    }
}