SideStore/AltStore/Components/NavigationBar.swift

//
//  NavigationBar.swift
//  AltStore
//
//  Created by Riley Testut on 7/15/19.
//  Copyright © 2019 Riley Testut. All rights reserved.
//

import UIKit

import Roxas

final class NavigationBar: UINavigationBar
{
    @IBInspectable var automaticallyAdjustsItemPositions: Bool = true
    
    private let backgroundColorView = UIView()
    
    override init(frame: CGRect)
    {
        super.init(frame: frame)
        
        self.initialize()
    }
    
    required init?(coder aDecoder: NSCoder)
    {
        super.init(coder: aDecoder)
        
        self.initialize()
    }
    
    private func initialize()
    {
        if #available(iOS 13, *)
        {
            let standardAppearance = UINavigationBarAppearance()
            standardAppearance.configureWithDefaultBackground()
            standardAppearance.shadowColor = nil
            
            let edgeAppearance = UINavigationBarAppearance()
            edgeAppearance.configureWithOpaqueBackground()
            edgeAppearance.backgroundColor = self.barTintColor
            edgeAppearance.shadowColor = nil
            
            if let tintColor = self.barTintColor
            {
                let textAttributes = [NSAttributedString.Key.foregroundColor: UIColor.white]
                
                standardAppearance.backgroundColor = tintColor
                standardAppearance.titleTextAttributes = textAttributes
                standardAppearance.largeTitleTextAttributes = textAttributes
                
                edgeAppearance.titleTextAttributes = textAttributes
                edgeAppearance.largeTitleTextAttributes = textAttributes
            }
            else
            {
                standardAppearance.backgroundColor = nil
            }
            
            self.scrollEdgeAppearance = edgeAppearance
            self.standardAppearance = standardAppearance
        }
        else
        {
            self.shadowImage = UIImage()
            
            if let tintColor = self.barTintColor
            {
                self.backgroundColorView.backgroundColor = tintColor
                
                // Top = -50 to cover status bar area above navigation bar on any device.
                // Bottom = -1 to prevent a flickering gray line from appearing.
                self.addSubview(self.backgroundColorView, pinningEdgesWith: UIEdgeInsets(top: -50, left: 0, bottom: -1, right: 0))
            }
            else
            {
                self.barTintColor = .white
            }
        }
    }
    
    override func layoutSubviews()
    {
        super.layoutSubviews()
        
        if self.backgroundColorView.superview != nil
        {
            self.insertSubview(self.backgroundColorView, at: 1)
        }
        
        if self.automaticallyAdjustsItemPositions
        {
            // We can't easily shift just the back button up, so we shift the entire content view slightly.
            for contentView in self.subviews
            {
                guard NSStringFromClass(type(of: contentView)).contains("ContentView") else { continue }
                contentView.center.y -= 2
            }
        }
    }
}