Tokamak/Sources/TokamakDOM/App/ColorSchemeObserver.swift

43 lines
1.4 KiB
Swift

// Copyright 2020-2021 Tokamak contributors
//
// 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 JavaScriptKit
import OpenCombineShim
enum ColorSchemeObserver {
static var publisher = CurrentValueSubject<ColorScheme, Never>(
.init(matchMediaDarkScheme: matchMediaDarkScheme)
)
private static var closure: JSClosure?
private static var cancellable: AnyCancellable?
static func observe(_ rootElement: JSObject) {
let closure = JSClosure {
publisher.value = .init(matchMediaDarkScheme: $0[0].object!)
return .undefined
}
_ = matchMediaDarkScheme.addListener!(closure)
Self.closure = closure
Self.cancellable = Self.publisher.sink { colorScheme in
let systemBackground: String
switch colorScheme {
case .light: systemBackground = "#FFFFFF"
case .dark: systemBackground = "rgb(38, 38, 38)"
}
rootElement.style.object!.backgroundColor = .string("\(systemBackground)")
}
}
}