//
//  Copyright (c) 2020 Touch Instinct
//
//  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

extension UIPanGestureRecognizer {
    func projectedLocation(decelerationRate: UIScrollView.DecelerationRate) -> CGPoint {
        let velocityOffset = velocity(in: view).projectedOffset(decelerationRate: .normal)
        let projectedLocation = location(in: view) + velocityOffset
        return projectedLocation
    }
}

extension CGPoint {
    func projectedOffset(decelerationRate: UIScrollView.DecelerationRate) -> CGPoint {
        return CGPoint(x: x.projectedOffset(decelerationRate: decelerationRate),
                       y: y.projectedOffset(decelerationRate: decelerationRate))
    }
}

extension CGFloat {
    func projectedOffset(decelerationRate: UIScrollView.DecelerationRate) -> CGFloat {
        let multiplier = 1 / (1 - decelerationRate.rawValue) / 1000
        return self * multiplier
    }
}

extension CGPoint {
    static func +(left: CGPoint, right: CGPoint) -> CGPoint {
        return CGPoint(x: left.x + right.x,
                       y: left.y + right.y)
    }
}