/*
 * Copyright (C) 2018 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

#if PLATFORM(IOS_FAMILY)

namespace WebCore {
class FloatPoint;
}

namespace WebKit {

enum class ScrollingIncrement : uint8_t {
    Document,
    Page,
    Line
};

enum class ScrollingDirection : uint8_t {
    Up,
    Down,
    Left,
    Right
};

}

@class UIScrollView;
@class WebEvent;
@protocol WKKeyboardScrollViewAnimatorDelegate;

@interface WKKeyboardScrollViewAnimator : NSObject

- (instancetype)init NS_UNAVAILABLE;
- (instancetype)initWithScrollView:(UIScrollView *)scrollView;

- (void)invalidate;

- (void)willStartInteractiveScroll;

- (BOOL)beginWithEvent:(::WebEvent *)event;
- (void)handleKeyEvent:(::WebEvent *)event;

- (BOOL)scrollTriggeringKeyIsPressed;

@property (nonatomic, weak) id <WKKeyboardScrollViewAnimatorDelegate> delegate;

@end

@protocol WKKeyboardScrollViewAnimatorDelegate <NSObject>
@optional
- (BOOL)isScrollableForKeyboardScrollViewAnimator:(WKKeyboardScrollViewAnimator *)animator;
- (CGFloat)keyboardScrollViewAnimator:(WKKeyboardScrollViewAnimator *)animator distanceForIncrement:(WebKit::ScrollingIncrement)increment inDirection:(WebKit::ScrollingDirection)direction;
- (void)keyboardScrollViewAnimatorWillScroll:(WKKeyboardScrollViewAnimator *)animator;
- (void)keyboardScrollViewAnimatorDidFinishScrolling:(WKKeyboardScrollViewAnimator *)animator;

@end

#endif // PLATFORM(IOS_FAMILY)