HBTools.swift

import Foundation
import UIKit
import Photos

class HBTools {
    
    static let appName = Bundle.main.object(forInfoDictionaryKey: "CFBundleName") as? String ?? "String_appName"
    
    enum Orientation {
        case portrait
        case landscape
    }
    
    static func getScreenDimensions(for orientation: Orientation = .portrait) -> CGSize {
        var width = UIScreen.main.bounds.width,
            height = UIScreen.main.bounds.height
        switch orientation {
        case .portrait: // Height > width
            if width > height {
                width = height
                height = UIScreen.main.bounds.width
            }
        case .landscape: // Width > height
            if height > width {
                height = width
                width = UIScreen.main.bounds.height
            }
        }
        return CGSize(width: width, height: height)
    }
    
    static func doNothing() {}
    
    static func presentImagePicker(_ picker: UIImagePickerController, fromViewController viewController: UIViewController) {
        switch PHPhotoLibrary.authorizationStatus() {
        case .authorized:
            viewController.present(picker, animated: true)
        case .notDetermined:
            PHPhotoLibrary.requestAuthorization(for: .readWrite) {
                [weak viewController] newStatus in
                if newStatus == PHAuthorizationStatus.authorized {
                    DispatchQueue.main.async {
                        viewController?.present(picker, animated: true)
                    }
                }
            }
        case .limited: // The user authorized this app for limited photo library access
            fallthrough
        case .denied: // The user explicitly denied this app access to the photo library
            let title = "\"\(appName)\" Would Like to Access Your Photos",
                message = Bundle.main.object(forInfoDictionaryKey: "NSPhotoLibraryUsageDescription") as? String
            let alert = getAlert(title: title, message: message, cancelActionTitle: "Don't Allow", primaryActionTitle: "Allow Full Access in Settings") {
                _ in openApplicationSettingsPane()
            }
            viewController.present(alert, animated: true)
        case .restricted: // The app isn’t authorized to access the photo library, and the user can’t grant such permission
            let title = "\"\(appName)\" Was Unable to Access to Your Photos",
                message = "This app requires permission to access to your photos. However, it seems like your device is in a restricted state and unable to grant such permission."
            let alert = getAlert(title: title, message: message, cancelActionTitle: "OK")
            viewController.present(alert, animated: true)
        @unknown default:
            fatalError("Unable to determine user's photo library authorization status.")
        }
    }
    
    static func log(_ items: Any) {
        print("[log] \(getDateString(withFormat: "dd-MM-YYYY hh:mm:ss")) \(items)")
    }
    
    static func openApplicationSettingsPane() {
        UIApplication.shared.open(URL(string: UIApplication.openSettingsURLString)!)
    }
    
    static func getAlert(title: String? = nil, message: String?, cancelActionTitle: String = "Cancel", primaryActionTitle: String = "Continue", primaryAction: ((UIAlertAction) -> Void)? = nil) -> UIAlertController {
        let alert = UIAlertController(title: title, message: message, preferredStyle: .alert)
        alert.addAction(UIAlertAction(title: cancelActionTitle, style: .cancel))
        if primaryAction != nil {
            alert.addAction(UIAlertAction(title: primaryActionTitle, style: .default, handler: primaryAction))
        }
        return alert
    }
    
    static func getDateString(fromDate date: Date = Date(), withFormat format: String) -> String {
        let dateFormatter = DateFormatter()
        dateFormatter.dateFormat = format
        return dateFormatter.string(from: date)
    }
    
    // Thanks to @TwoStraws
    static func getDocumentsDirectory() -> URL {
        let paths = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)
        return paths[0]
    }
}