space-ios/iOSClient/Main/NCMainTabBar.swift

//
//  NCMainTabBar.swift
//  Nextcloud
//
//  Created by Marino Faggiana on 06/01/2020.
//  Copyright © 2020 Marino Faggiana. All rights reserved.
//
//  Author Marino Faggiana <marino.faggiana@nextcloud.com>
//
//  This program is free software: you can redistribute it and/or modify
//  it under the terms of the GNU General Public License as published by
//  the Free Software Foundation, either version 3 of the License, or
//  (at your option) any later version.
//
//  This program is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU General Public License for more details.
//
//  You should have received a copy of the GNU General Public License
//  along with this program.  If not, see <http://www.gnu.org/licenses/>.
//

import Foundation

@IBDesignable class NCMainTabBar: UITabBar {

    override var traitCollection: UITraitCollection {
        return UITraitCollection(horizontalSizeClass: .compact)
    }

    override var backgroundColor: UIColor? {
        get {
            return self.fillColor
        }
        set {
            fillColor = newValue
            self.setNeedsDisplay()
        }
    }
    
    private var fillColor: UIColor!
    private var shapeLayer: CALayer?

    private func addShape() {
        let shapeLayer = CAShapeLayer()
        shapeLayer.path = createPath()
        shapeLayer.fillColor = backgroundColor?.cgColor


        if let oldShapeLayer = self.shapeLayer {
            self.layer.replaceSublayer(oldShapeLayer, with: shapeLayer)
        } else {
            self.layer.insertSublayer(shapeLayer, at: 0)
        }

        self.shapeLayer = shapeLayer
    }

    override func layoutSubviews() {
        super.layoutSubviews()
        self.layer.shadowPath = createPath()
        self.layer.shadowRadius = 5
        self.layer.shadowOffset = .zero
        self.layer.shadowOpacity = 0.25
    }

    override func draw(_ rect: CGRect) {
        self.addShape()
    }

    func createPath() -> CGPath {
        let height: CGFloat = 28
        let margin: CGFloat = 8
        let path = UIBezierPath()
        let centerWidth = self.frame.width / 2

        path.move(to: CGPoint(x: 0, y: 0)) // start top left
        path.addLine(to: CGPoint(x: (centerWidth - height - margin), y: 0)) // the beginning of the trough
        // first curve down
        path.addArc(withCenter: CGPoint(x: centerWidth, y: 0), radius: height + margin, startAngle: CGFloat(180 * Double.pi / 180), endAngle: CGFloat(0 * Double.pi / 180), clockwise: false)
        // complete the rect
        path.addLine(to: CGPoint(x: self.frame.width, y: 0))
        path.addLine(to: CGPoint(x: self.frame.width, y: self.frame.height))
        path.addLine(to: CGPoint(x: 0, y: self.frame.height))
        path.close()

        return path.cgPath
    }

    override func point(inside point: CGPoint, with event: UIEvent?) -> Bool {
        let button = self.viewWithTag(99)
        if self.bounds.contains(point) || (button != nil && button!.frame.contains(point)) {
            return true
        } else {
            return false
        }
    }

    func createPathCircle() -> CGPath {
        let radius: CGFloat = 37.0
        let path = UIBezierPath()
        let centerWidth = self.frame.width / 2

        path.move(to: CGPoint(x: 0, y: 0))
        path.addLine(to: CGPoint(x: (centerWidth - radius * 2), y: 0))
        path.addArc(withCenter: CGPoint(x: centerWidth, y: 0), radius: radius, startAngle: CGFloat(180).degreesToRadians, endAngle: CGFloat(0).degreesToRadians, clockwise: false)
        path.addLine(to: CGPoint(x: self.frame.width, y: 0))
        path.addLine(to: CGPoint(x: self.frame.width, y: self.frame.height))
        path.addLine(to: CGPoint(x: 0, y: self.frame.height))
        path.close()
        return path.cgPath
    }

}
extension CGFloat {
    var degreesToRadians: CGFloat { return self * .pi / 180 }
    var radiansToDegrees: CGFloat { return self * 180 / .pi }
}