mastodon-ios/Mastodon/Extension/UIView.swift

//
//  UIView.swift
//  Mastodon
//
//  Created by sxiaojian on 2021/2/4.
//

import UIKit

// MARK: - Convenience view creation method
extension UIView {

    static let separatorColor: UIColor = {
        UIColor(dynamicProvider: { collection in
            switch collection.userInterfaceStyle {
            case .dark:
                return ThemeService.shared.currentTheme.value.separator
            default:
                return .separator
            }
        })
    }()
    
    static var separatorLine: UIView {
        let line = UIView()
        line.backgroundColor = UIView.separatorColor
        return line
    }
    
    static func separatorLineHeight(of view: UIView) -> CGFloat {
        return 1.0 / view.traitCollection.displayScale
    }
    
}

// MARK: - Convenience view appearance modification method
extension UIView {
    @discardableResult
    func applyCornerRadius(radius: CGFloat) -> Self {
        layer.masksToBounds = true
        layer.cornerRadius = radius
        layer.cornerCurve = .continuous
        return self
    }
    
    @discardableResult
    func applyShadow(
        color: UIColor,
        alpha: Float,
        x: CGFloat,
        y: CGFloat,
        blur: CGFloat,
        spread: CGFloat = 0) -> Self
    {
        layer.masksToBounds = false
        layer.shadowColor = color.cgColor
        layer.shadowOpacity = alpha
        layer.shadowOffset = CGSize(width: x, height: y)
        layer.shadowRadius = blur / 2.0
        if spread == 0 {
            layer.shadowPath = nil
        } else {
            let dx = -spread
            let rect = bounds.insetBy(dx: dx, dy: dx)
            layer.shadowPath = UIBezierPath(rect: rect).cgPath
        }
        return self
    }
}