bundesmessenger-ios/bwi/Tools/BWIThemeService.swift

//
/*
 * Copyright (c) 2022 BWI GmbH
 *
 * 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 Foundation
import Combine

class BWIThemeService: ObservableObject {
    static let shared = BWIThemeService()
    @Published var themeId: String?
    @Published var theme: Theme
    @Published var isCurrentThemeDark: Bool
    var cancellable: Cancellable?
    
    private init() {
        let service = ThemeService.shared()
        themeId = service.themeId
        theme = service.theme
        isCurrentThemeDark = service.isCurrentThemeDark()
        
        cancellable = NotificationCenter.default
            .publisher(for: .themeServiceDidChangeTheme)
            .receive(on: DispatchQueue.main)
            .sink() { _ in
                self.themeDidChange()
            }
    }
    
    private func themeDidChange() {
        let service = ThemeService.shared()
        themeId = service.themeId
        theme = service.theme
        isCurrentThemeDark = service.isCurrentThemeDark()
    }
}