/*

See LICENSE folder for this sample’s licensing information.

Abstract:

This sample's detail view controller showing the accessibility examples.

*/

import Cocoa

import MediaLibrary

class DetailViewController: NSViewController {

    @IBOutlet var descriptionField: NSTextField!

    @IBOutlet var exampleArea: NSView!

    var detailItemRecord: Example! {

        didSet {

            // Remove the old child view controller, if any exists.

            if !childViewControllers.isEmpty {

                let vc = childViewControllers[0]

                vc.view.isHidden = true

                vc.removeFromParentViewController()

            }

            descriptionField.stringValue = ""

            guard detailItemRecord != nil else { return }

            // Update the description of the example.

            descriptionField.stringValue = detailItemRecord.desc

            // Check if this sample actually has a valid view controller to display.

            guard !detailItemRecord.viewControllerIdentifier.characters.isEmpty else { return }

            // Load the example storyboard and embed.

            let storyboard: NSStoryboard =

                NSStoryboard(name: NSStoryboard.Name(rawValue: detailItemRecord.viewControllerIdentifier), bundle: nil)

            let sceneIdentifier = NSStoryboard.SceneIdentifier(rawValue: detailItemRecord.viewControllerIdentifier)

            guard let buttonViewController =

                storyboard.instantiateController(withIdentifier: sceneIdentifier) as? NSViewController else { return }

            insertChildViewController(buttonViewController, at: 0)

            buttonViewController.view.translatesAutoresizingMaskIntoConstraints = false

            view.addSubview(buttonViewController.view)

            // Add the proper constraints to the detail view controller so it embeds properly with it's parent view controller.

            let top = NSLayoutConstraint(item: buttonViewController.view,

                                         attribute: .top,

                                         relatedBy: .equal,

                                         toItem: exampleArea,

                                         attribute: .top,

                                         multiplier: 1,

                                         constant: 0)

            let left = NSLayoutConstraint(item: buttonViewController.view,

                                          attribute: .left,

                                          relatedBy: .equal,

                                          toItem: exampleArea,

                                          attribute: .left,

                                          multiplier: 1,

                                          constant: 0)

            let height = NSLayoutConstraint(item: buttonViewController.view,

                                            attribute: .height,

                                            relatedBy: .equal,

                                            toItem: exampleArea,

                                            attribute: .height,

                                            multiplier: 1,

                                            constant: 0)

            let width = NSLayoutConstraint(item: buttonViewController.view,

                                           attribute: .width,

                                           relatedBy: .equal,

                                           toItem: exampleArea,

                                           attribute: .width,

                                           multiplier: 1,

                                           constant: 0)

            view.addConstraints([top, left, height, width])

        }

    }

}