//
// Copyright 2024 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 UIKit

class AppMediator: AppMediatorProtocol {
    private let windowManager: WindowManagerProtocol
        
    // UIApplication.State won't update if we store this e.g. in the constructor
    private var application: UIApplication {
        UIApplication.shared
    }
    
    init(windowManager: WindowManagerProtocol) {
        self.windowManager = windowManager
    }
    
    func beginBackgroundTask(withName taskName: String?, expirationHandler handler: (() -> Void)?) -> UIBackgroundTaskIdentifier {
        application.beginBackgroundTask(withName: taskName, expirationHandler: handler)
    }

    func endBackgroundTask(_ identifier: UIBackgroundTaskIdentifier) {
        application.endBackgroundTask(identifier)
    }
    
    func open(_ url: URL) {
        application.open(url, options: [:], completionHandler: nil)
    }
    
    func openAppSettings() {
        guard let url = URL(string: UIApplication.openSettingsURLString) else {
            return
        }
        
        open(url)
    }

    var backgroundTimeRemaining: TimeInterval {
        application.backgroundTimeRemaining
    }

    @MainActor
    var appState: UIApplication.State {
        switch application.applicationState {
        case .active:
            windowManager.mainWindow.traitCollection.activeAppearance == .active ? .active : .inactive
        case .inactive:
            .inactive
        case .background:
            .background
        default:
            .inactive
        }
    }
}