JSJP_Student_sw/Pods/RxGesture/Pod/Classes/iOS/TransformGestureRecognizers.swift

// Copyright (c) RxSwiftCommunity

// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
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// 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
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// THE SOFTWARE.

import UIKit
import RxSwift
import RxCocoa

public struct TransformGestureRecognizers {
    public let panGesture: UIPanGestureRecognizer
    public let rotationGesture: UIRotationGestureRecognizer
    public let pinchGesture: UIPinchGestureRecognizer
}

public struct TransformVelocity {
    let translation: CGPoint
    let rotation: CGFloat
    let scale: CGFloat
}

public typealias TransformConfiguration = Configuration<TransformGestureRecognizers>
public typealias TransformControlEvent = ControlEvent<TransformGestureRecognizers>
public typealias TransformObservable = Observable<TransformGestureRecognizers>

extension Reactive where Base: View {
    public func transformGestures(
        configuration: TransformConfiguration? = nil
        ) -> TransformControlEvent {

        let source = Observable.combineLatest(panGesture(), rotationGesture(), pinchGesture()) {
            return TransformGestureRecognizers(
                panGesture: $0,
                rotationGesture: $1,
                pinchGesture: $2
            )
        }

        return ControlEvent(events: source)
    }
}

extension ObservableType where Element == TransformGestureRecognizers {

    public func when(_ states: GestureRecognizerState...) -> Observable<Element> {
        return filter { gestures in
            return states.contains(gestures.panGesture.state)
                || states.contains(gestures.rotationGesture.state)
                || states.contains(gestures.pinchGesture.state)
        }
    }

    public func asTransform(in view: TargetView = .view) -> Observable<(transform: CGAffineTransform, velocity: TransformVelocity)> {
        return self.map { gestures in
            let translationView = view.targetView(for: gestures.panGesture)
            let translation = gestures.panGesture.translation(in: translationView)

            let transform = CGAffineTransform.identity
                .rotated(by: gestures.rotationGesture.rotation)
                .scaledBy(x: gestures.pinchGesture.scale, y: gestures.pinchGesture.scale)
                .translatedBy(x: translation.x, y: translation.y)

            let velocity = TransformVelocity(
                translation: gestures.panGesture.velocity(in: translationView),
                rotation: gestures.rotationGesture.velocity,
                scale: gestures.pinchGesture.velocity
            )

            return (transform, velocity)
        }
    }
}