Adds basic AppDetailViewController implementation

AltStore/Apps/AppDetailViewController.swift

@@ -0,0 +1,110 @@
+//
+//  AppDetailViewController.swift
+//  AltStore
+//
+//  Created by Riley Testut on 5/9/19.
+//  Copyright © 2019 Riley Testut. All rights reserved.
+//
+
+import UIKit
+import Roxas
+
+@objc(ScreenshotCollectionViewCell)
+private class ScreenshotCollectionViewCell: UICollectionViewCell
+{
+    @IBOutlet var imageView: UIImageView!
+}
+
+extension AppDetailViewController
+{
+    private enum Row: Int
+    {
+        case general
+        case screenshots
+        case description
+    }
+}
+
+class AppDetailViewController: UITableViewController
+{
+    var app: App!
+    
+    private lazy var screenshotsDataSource = self.makeScreenshotsDataSource()
+    
+    @IBOutlet private var nameLabel: UILabel!
+    @IBOutlet private var subtitleLabel: UILabel!
+    @IBOutlet private var developerButton: UIButton!
+    @IBOutlet private var appIconImageView: UIImageView!
+    
+    @IBOutlet private var downloadButton: UIButton!
+    
+    @IBOutlet private var screenshotsCollectionView: UICollectionView!
+    
+    @IBOutlet private var descriptionLabel: UILabel!
+    
+    override func viewDidLoad()
+    {
+        super.viewDidLoad()
+        
+        self.tableView.delegate = self
+        self.screenshotsCollectionView.dataSource = self.screenshotsDataSource
+        
+        self.update()
+    }
+    
+    override func viewDidLayoutSubviews()
+    {
+        super.viewDidLayoutSubviews()
+        
+        guard let image = self.screenshotsDataSource.items.first else { return }
+        
+        let aspectRatio = image.size.width / image.size.height
+        
+        let height = self.screenshotsCollectionView.bounds.height
+        let width = self.screenshotsCollectionView.bounds.height * aspectRatio
+        
+        let layout = self.screenshotsCollectionView.collectionViewLayout as! UICollectionViewFlowLayout
+        layout.itemSize = CGSize(width: width, height: height)
+    }
+}
+
+private extension AppDetailViewController
+{
+    func update()
+    {
+        self.nameLabel.text = self.app.name
+        self.subtitleLabel.text = self.app.subtitle
+        self.developerButton.setTitle(self.app.developer, for: .normal)
+        self.appIconImageView.image = UIImage(named: self.app.iconName)
+        
+        let text = String(format: NSLocalizedString("Download %@", comment: ""), self.app.name)
+        self.downloadButton.setTitle(text, for: .normal)
+        
+        self.descriptionLabel.text = self.app.localizedDescription
+    }
+    
+    func makeScreenshotsDataSource() -> RSTArrayCollectionViewDataSource<UIImage>
+    {
+        let screenshots = self.app.screenshotNames.compactMap(UIImage.init(named:))
+        
+        let dataSource = RSTArrayCollectionViewDataSource(items: screenshots)
+        dataSource.cellConfigurationHandler = { (cell, screenshot, indexPath) in
+            let cell = cell as! ScreenshotCollectionViewCell
+            cell.imageView.image = screenshot
+        }
+        
+        return dataSource
+    }
+}
+
+extension AppDetailViewController
+{
+    override func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat
+    {
+        guard indexPath.row == Row.screenshots.rawValue else { return super.tableView(tableView, heightForRowAt: indexPath) }
+        guard !self.screenshotsDataSource.items.isEmpty else { return 0.0 }
+        
+        let height = self.view.bounds.height * 0.67
+        return height
+    }
+}

AltStore/Apps/AppsViewController.swift

@@ -22,6 +22,18 @@ class AppsViewController: UITableViewController
         // Hide trailing row separators.
         self.tableView.tableFooterView = UIView()
     }
+    
+    override func prepare(for segue: UIStoryboardSegue, sender: Any?)
+    {
+        guard segue.identifier == "showAppDetail" else { return }
+        
+        guard let cell = sender as? UITableViewCell, let indexPath = self.tableView.indexPath(for: cell) else { return }
+        
+        let app = self.dataSource.item(at: indexPath)
+        
+        let appDetailViewController = segue.destination as! AppDetailViewController
+        appDetailViewController.app = app
+    }
 }
 
 private extension AppsViewController