passepartout-apple/Passepartout/App/Reusable/LockableView.swift

140 lines
3.1 KiB
Swift

//
// LockableView.swift
// Passepartout
//
// Created by Davide De Rosa on 3/20/23.
// Copyright (c) 2023 Davide De Rosa. All rights reserved.
//
// https://github.com/passepartoutvpn
//
// This file is part of Passepartout.
//
// Passepartout is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Passepartout 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Passepartout. If not, see <http://www.gnu.org/licenses/>.
//
import SwiftUI
struct LockableView<Content: View, LockedContent: View>: View {
@Binding var locksInBackground: Bool
let content: () -> Content
let lockedContent: () -> LockedContent
let unlockBlock: () async -> Bool
@Environment(\.scenePhase) private var scenePhase
@ObservedObject private var lock: Lock = .shared
@Binding private var state: Lock.State
init(
locksInBackground: Binding<Bool>,
content: @escaping () -> Content,
lockedContent: @escaping () -> LockedContent,
unlockBlock: @escaping () async -> Bool
) {
_locksInBackground = locksInBackground
self.content = content
self.lockedContent = lockedContent
self.unlockBlock = unlockBlock
_state = .init {
Lock.shared.state
} set: {
Lock.shared.state = $0
}
}
var body: some View {
ZStack {
content()
if locksInBackground && state != .none {
lockedContent()
}
}.onChange(of: scenePhase, perform: onScenePhase)
}
}
// MARK: -
private final class Lock: ObservableObject {
enum State {
case none
case covered
case locked
}
static let shared = Lock()
@Published var state: State = .locked
private init() {
}
}
// MARK: -
private extension LockableView {
func onScenePhase(_ scenePhase: ScenePhase) {
switch scenePhase {
case .active:
unlockIfNeeded()
case .inactive:
if state == .none {
state = .covered
}
case .background:
lockIfNeeded()
default:
break
}
}
func lockIfNeeded() {
guard locksInBackground else {
return
}
state = .locked
}
func unlockIfNeeded() {
guard locksInBackground else {
state = .none
return
}
switch state {
case .none:
break
case .covered:
state = .none
case .locked:
Task { @MainActor in
guard await unlockBlock() else {
return
}
state = .none
}
}
}
}