Gemini/Gemini-iOS/SceneDelegate.swift

//
//  SceneDelegate.swift
//  Gemini-iOS
//
//  Created by Shadowfacts on 7/15/20.
//

import UIKit
import SwiftUI
import BrowserCore
import SafariServices
import Combine

class SceneDelegate: UIResponder, UIWindowSceneDelegate {

    var window: UIWindow?

    var navigationManager: NavigationManager!
    
    private var cancellables = [AnyCancellable]()

    func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
        // Use this method to optionally configure and attach the UIWindow `window` to the provided UIWindowScene `scene`.
        // If using a storyboard, the `window` property will automatically be initialized and attached to the scene.
        // This delegate does not imply the connecting scene or session are new (see `application:configurationForConnectingSceneSession` instead).

        let initialURL: URL
        
        if let context = connectionOptions.urlContexts.first {
            initialURL = context.url
        } else {
            if ProcessInfo.processInfo.environment.keys.contains("DEFAULT_URL") {
                initialURL = URL(string: ProcessInfo.processInfo.environment["DEFAULT_URL"]!)!
            } else {
                initialURL = URL(string: "gemini://gemini.circumlunar.space/")!
            }
        }
        
        navigationManager = NavigationManager(url: initialURL)
        navigationManager.delegate = self
        
        // Create the SwiftUI view that provides the window contents.
        let contentView = ContentView(navigator: navigationManager, shareCurrentURL: self.shareCurrentURL)

        // Use a UIHostingController as window root view controller.
        if let windowScene = scene as? UIWindowScene {
            let window = UIWindow(windowScene: windowScene)
            window.overrideUserInterfaceStyle = Preferences.shared.theme
            window.rootViewController = UIHostingController(rootView: contentView)
//            window.rootViewController = BrowserViewController(navigator: navigationManager)
            self.window = window
            window.makeKeyAndVisible()
        }
        
        Preferences.shared.$theme
            .sink { (newStyle) in
                self.window!.overrideUserInterfaceStyle = newStyle
            }
            .store(in: &cancellables)
    }
    
    func scene(_ scene: UIScene, openURLContexts URLContexts: Set<UIOpenURLContext>) {
        if let context = URLContexts.first {
            navigationManager.changeURL(context.url)
        }
    }

    func sceneDidDisconnect(_ scene: UIScene) {
        // Called as the scene is being released by the system.
        // This occurs shortly after the scene enters the background, or when its session is discarded.
        // Release any resources associated with this scene that can be re-created the next time the scene connects.
        // The scene may re-connect later, as its session was not necessarily discarded (see `application:didDiscardSceneSessions` instead).
    }

    func sceneDidBecomeActive(_ scene: UIScene) {
        // Called when the scene has moved from an inactive state to an active state.
        // Use this method to restart any tasks that were paused (or not yet started) when the scene was inactive.
    }

    func sceneWillResignActive(_ scene: UIScene) {
        // Called when the scene will move from an active state to an inactive state.
        // This may occur due to temporary interruptions (ex. an incoming phone call).
    }

    func sceneWillEnterForeground(_ scene: UIScene) {
        // Called as the scene transitions from the background to the foreground.
        // Use this method to undo the changes made on entering the background.
    }

    func sceneDidEnterBackground(_ scene: UIScene) {
        // Called as the scene transitions from the foreground to the background.
        // Use this method to save data, release shared resources, and store enough scene-specific state information
        // to restore the scene back to its current state.
    }
    
    private func shareCurrentURL() {
        let vc = UIActivityViewController(activityItems: [navigationManager.currentURL], applicationActivities: nil)
        window?.rootViewController?.present(vc, animated: true)
    }

}

extension SceneDelegate: NavigationManagerDelegate {
    func loadNonGeminiURL(_ url: URL) {
        UIApplication.shared.open(url, options: [.universalLinksOnly: true]) { (success) in
            if !success {
                if Preferences.shared.useInAppSafari {
                    let config = SFSafariViewController.Configuration()
                    config.entersReaderIfAvailable = Preferences.shared.useReaderMode
                    let vc = SFSafariViewController(url: url, configuration: config)
                    self.window?.rootViewController?.present(vc, animated: true)
                } else {
                    UIApplication.shared.open(url, options: [:])
                }
            }
        }
    }
}