AlertKit/Sources/SPAlert/SPAlertView.swift

// The MIT License (MIT)
// Copyright © 2020 Ivan Vorobei (hello@ivanvorobei.io)
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.

import UIKit

/**
 SPAlert: Main view. Can be customisable if need.
 
 For change duration, check method `present` and pass duration and other specific property if need customise.
 
 Here available set window on which shoud be present.
 If you have some windows, you shoud configure it. Check property `presentWindow`.
 
 For disable dismiss by tap, check property `.dismissByTap`.
 
 Recomended call `SPAlert` and choose style func.
 */
@available(iOSApplicationExtension, unavailable)
open class SPAlertView: UIView {
    
    open var completion: (() -> Void)? = nil
    
    // MARK: - Properties
    
    /**
     SPAlert: Wrapper of corner radius of alert.
     */
    @objc dynamic open var cornerRadius: CGFloat = 8 {
        didSet {
            layer.cornerRadius = self.cornerRadius
        }
    }
    
    /**
     SPAlert: Dismiss alert by tap in any place inside. By default is on.
     */
    @objc dynamic open var dismissByTap: Bool = true
    
    /**
     SPAlert: Automatically dismiss in time or not. Duration of dismiss can be changed by property `duration`.
     */
    @objc dynamic open var dismissInTime: Bool = true
    
    /**
     SPAlert: Duration for showing alert. If `dismissInTime` disabled, this property ignoring.
     */
    @objc dynamic open var duration: TimeInterval = 1.5
    
    // MARK: - Views
    
    open var titleLabel: UILabel?
    open var subtitleLabel: UILabel?
    open var iconView: UIView?
    
    private lazy var backgroundView: UIVisualEffectView = {
        let view: UIVisualEffectView = {
            if #available(iOS 13.0, *) {
                return UIVisualEffectView(effect: UIBlurEffect(style: .systemThickMaterial))
            } else {
                return UIVisualEffectView(effect: UIBlurEffect(style: .light))
            }
        }()
        view.isUserInteractionEnabled = false
        return view
    }()
    
    weak open var presentWindow: UIWindow?
    
    // MARK: - Init
    
    public convenience init(title: String, message: String? = nil, preset: SPAlertIconPreset) {
        self.init(preset: preset)
        setTitle(title)
        if let message = message {
            setMessage(message)
        }
        setIcon(for: preset)
        
        switch preset {
        case .spinner:
            dismissInTime = false
            dismissByTap = false
        default:
            dismissInTime = true
            dismissByTap = true
        }
    }
    
    public init(preset: SPAlertIconPreset) {
        super.init(frame: CGRect.zero)
        commonInit()
        layout = SPAlertLayout(for: preset)
    }
    
    public init(message: String) {
        super.init(frame: CGRect.zero)
        commonInit()
        layout = SPAlertLayout.message()
        setMessage(message)
        dismissInTime = true
        dismissByTap = true
    }
    
    public required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        commonInit()
        dismissInTime = true
        dismissByTap = true
    }
    
    private func commonInit() {
        preservesSuperviewLayoutMargins = false
        if #available(iOS 11.0, *) {
            insetsLayoutMarginsFromSafeArea = false
        }
        
        layer.masksToBounds = true
        backgroundColor = .clear
        addSubview(backgroundView)
        
        setCornerRadius(self.cornerRadius)
    }
    
    // MARK: - Configure
    
    private func setTitle(_ text: String) {
        let label = UILabel()
        label.font = UIFont.preferredFont(forTextStyle: .title2, weight: .bold)
        label.numberOfLines = 0
        let style = NSMutableParagraphStyle()
        style.lineSpacing = 3
        style.alignment = .center
        label.attributedText = NSAttributedString(string: text, attributes: [.paragraphStyle: style])
        label.textColor = defaultContentColor
        titleLabel = label
        addSubview(label)
    }
    
    private func setMessage(_ text: String) {
        let label = UILabel()
        label.font = UIFont.preferredFont(forTextStyle: .body)
        label.numberOfLines = 0
        let style = NSMutableParagraphStyle()
        style.lineSpacing = 2
        style.alignment = .center
        label.attributedText = NSAttributedString(string: text, attributes: [.paragraphStyle: style])
        label.textColor = defaultContentColor
        subtitleLabel = label
        addSubview(label)
    }
    
    private func setIcon(for preset: SPAlertIconPreset) {
        let view = preset.createView()
        view.tintColor = defaultContentColor
        self.iconView = view
        addSubview(view)
    }
    
    private func setCornerRadius(_ value: CGFloat) {
        layer.cornerRadius = value
    }
    
    // MARK: - Present
    
    fileprivate var presentDismissDuration: TimeInterval = 0.2
    fileprivate var presentDismissScale: CGFloat = 0.8
    
    fileprivate var defaultContentColor: UIColor {
        let darkColor = UIColor(red: 127 / 255, green: 127 / 255, blue: 129 / 255, alpha: 1)
        let lightColor = UIColor(red: 88 / 255, green: 87 / 255, blue: 88 / 255, alpha: 1)
        if #available(iOS 12.0, *) {
            guard let interfaceStyle = self.window?.traitCollection.userInterfaceStyle else {
                return lightColor
            }
            switch interfaceStyle {
            case .light: return lightColor
            case .dark: return darkColor
            case .unspecified: return lightColor
            @unknown default: return lightColor
            }
        } else {
            return lightColor
        }
    }
    
    open func present(haptic: SPAlertHaptic = .success, completion: (() -> Void)? = nil) {
        
        if self.presentWindow == nil {
            self.presentWindow = UIApplication.shared.keyWindow
        }
        
        guard let window = self.presentWindow else { return }
        
        window.addSubview(self)
        
        // Prepare for present
        
        self.completion = completion
        
        alpha = 0
        setFrame()
        transform = transform.scaledBy(x: self.presentDismissScale, y: self.presentDismissScale)
        
        if dismissByTap {
            let tapGesterRecognizer = UITapGestureRecognizer(target: self, action: #selector(dismiss))
            addGestureRecognizer(tapGesterRecognizer)
        }
        
        // Present
        
        haptic.impact()
        
        UIView.animate(withDuration: presentDismissDuration, animations: {
            self.alpha = 1
            self.transform = CGAffineTransform.identity
        }, completion: { [weak self] finished in
            guard let self = self else { return }
            
            if let iconView = self.iconView as? SPAlertIconAnimatable {
                iconView.animate()
            }
            
            if self.dismissInTime {
                DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + self.duration) {
                    self.dismiss()
                }
            }
        })
    }
    
    @objc open func dismiss() {
        UIView.animate(withDuration: presentDismissDuration, animations: {
            self.alpha = 0
            self.transform = self.transform.scaledBy(x: self.presentDismissScale, y: self.presentDismissScale)
        }, completion: { [weak self] finished in
            self?.removeFromSuperview()
            self?.completion?()
        })
    }
    
    // MARK: - Layout
    
    open var layout: SPAlertLayout = .init()
    
    fileprivate func setFrame() {
        guard let window = self.presentWindow else { return }
        frame = CGRect.init(x: 0, y: 0, width: 250, height: 100)
        center = .init(x: window.frame.midX, y: window.frame.midY)
        layoutMargins = layout.margins
        sizeToFit()
        center = .init(x: window.frame.midX, y: window.frame.midY)
    }
    
    open override func sizeThatFits(_ size: CGSize) -> CGSize {
        layoutSubviews()
        let bottomY = [subtitleLabel, titleLabel, iconView].first(where: { $0 != nil })??.frame.maxY ?? 150
        return CGSize.init(width: frame.width, height: bottomY + layoutMargins.bottom)
    }
    
    open override func layoutSubviews() {
        super.layoutSubviews()
        backgroundView.frame = bounds
        if let iconView = self.iconView {
            iconView.frame = .init(origin: .init(x: 0, y: layoutMargins.top), size: layout.iconSize)
            iconView.center.x = bounds.midX
        }
        if let titleLabel = self.titleLabel {
            titleLabel.layoutDynamicHeight(
                x: layoutMargins.left,
                y: iconView == nil ? layoutMargins.top : (iconView?.frame.maxY ?? 0) + layout.spaceBetweenIconAndTitle,
                width: frame.width - layoutMargins.left - layoutMargins.right)
        }
        if let subtitleLabel = self.subtitleLabel {
            let yPosition: CGFloat = {
                if let titleLabel = self.titleLabel {
                    return titleLabel.frame.maxY + 4
                } else {
                    return layoutMargins.top
                }
            }()
            subtitleLabel.layoutDynamicHeight(x: layoutMargins.left, y: yPosition, width: frame.width - layoutMargins.left - layoutMargins.right)
        }
    }
}