//
//  CWInteractiveTransition.m
//  ViewControllerTransition
//
//  Created by chavez on 2017/6/28.
//  Copyright © 2017年 chavez. All rights reserved.
//

#import "CWInteractiveTransition.h"

@interface CWInteractiveTransition ()<UIGestureRecognizerDelegate>

@property (nonatomic,weak) UIViewController *weakVC;
@property (nonatomic,assign) CWDrawerTransitiontype type;
@property (nonatomic,assign) BOOL openEdgeGesture;
@property (nonatomic,assign) CWDrawerTransitionDirection direction;
@property (nonatomic,strong) CADisplayLink *link;
@property (nonatomic,copy) void(^transitionDirectionAutoBlock)(CWDrawerTransitionDirection direction);

@end

@implementation CWInteractiveTransition
{
    CGFloat _percent;
    CGFloat _remaincount;
    BOOL    _toFinish;
    CGFloat _oncePercent;
}

- (CADisplayLink *)link {
    if (!_link) {
        _link = [CADisplayLink displayLinkWithTarget:self selector:@selector(cw_update)];
        [_link addToRunLoop:[NSRunLoop currentRunLoop] forMode:NSRunLoopCommonModes];
    }
    return _link;
}

- (instancetype)initWithTransitiontype:(CWDrawerTransitiontype)type {
    if (self = [super init]) {
        _type = type;
        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(cw_singleTap) name:CWLateralSlideTapNoticationKey object:nil];
        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(cw_handleHiddenPan:) name:CWLateralSlidePanNoticationKey object:nil];
    }
    return self;
}

+ (instancetype)interactiveWithTransitiontype:(CWDrawerTransitiontype)type {
    return [[self alloc] initWithTransitiontype:type];
}

- (void)addPanGestureForViewController:(UIViewController *)viewController {
    
    self.weakVC = viewController;
    if (self.openEdgeGesture) {
        // 因为edges设置为（UIRectEdgeLeft | UIRectEdgeLeft）或者 UIRectEdgeAll都无效，所以增加左右两个边缘手势
        UIScreenEdgePanGestureRecognizer *edgePanFromLeft = [[UIScreenEdgePanGestureRecognizer alloc] initWithTarget:self action:@selector(cw_handleEdgePan:)];
        edgePanFromLeft.edges = UIRectEdgeLeft;
        edgePanFromLeft.delegate = self;
        [viewController.view addGestureRecognizer:edgePanFromLeft];
        
        UIScreenEdgePanGestureRecognizer *edgePanFromRight = [[UIScreenEdgePanGestureRecognizer alloc] initWithTarget:self action:@selector(cw_handleEdgePan:)];
        edgePanFromRight.edges = UIRectEdgeRight;
        edgePanFromRight.delegate = self;
        [viewController.view addGestureRecognizer:edgePanFromRight];
        
    }else {
        UIPanGestureRecognizer *pan = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(cw_handleShowPan:)];
        pan.delegate = self;
        [viewController.view addGestureRecognizer:pan];
    }
}

- (UIViewController *)viewController:(UIView *)view{
    for (UIView* next = view; next; next = next.superview) {
        UIResponder* nextResponder = [next nextResponder];
        if ([nextResponder isKindOfClass:[UIViewController class]]) {
            return (UIViewController*)nextResponder;
        }
    }
    return nil;
}

#pragma mark -GestureRecognizer
- (void)cw_singleTap {
    if (_type == CWDrawerTransitiontypeShow) return;
    [self.weakVC dismissViewControllerAnimated:YES completion:nil];
}

- (void)cw_handleHiddenPan:(NSNotification *)note {
    
    if (_type == CWDrawerTransitiontypeShow) return;
    UIPanGestureRecognizer *pan = note.object;
    [self handleGesture:pan];
}

- (void)cw_handleShowPan:(UIPanGestureRecognizer *)pan {
    
    if (_type == CWDrawerTransitiontypeHidden) return;
    [self handleGesture:pan];
}

- (void)hiddenBeganTranslationX:(CGFloat)x {
    if ((x > 0 && _direction == CWDrawerTransitionFromLeft ) ||
        (x < 0 && _direction == CWDrawerTransitionFromRight )) return;
    self.interacting = YES;
    [self.weakVC dismissViewControllerAnimated:YES completion:nil];
}

- (void)showBeganTranslationX:(CGFloat)x gesture:(UIPanGestureRecognizer *)pan {
//    NSLog(@"---->%f", x);
    if (x >= 0) _direction = CWDrawerTransitionFromLeft;
    else        _direction = CWDrawerTransitionFromRight;
    
    if ((x < 0 && _direction == CWDrawerTransitionFromLeft) ||
        (x > 0 && _direction == CWDrawerTransitionFromRight)) return;
    
    self.interacting = YES;
    if (_transitionDirectionAutoBlock) {
        _transitionDirectionAutoBlock(_direction);
    }
}

- (void)cw_updateInteractiveTransition {
    _percent = fminf(fmaxf(_percent, 0.003), 0.97);
    [self updateInteractiveTransition:_percent];
}

- (void)cw_endInteractiveTransition {
    self.interacting = NO;
    [self startTimerAnimationWithFinishTransition:_percent > self.configuration.finishPercent];
}

- (void)handleGesture:(UIPanGestureRecognizer *)pan  {
    
    CGFloat x = [pan translationInView:pan.view].x;
    _percent = 0;
    _percent = x / pan.view.frame.size.width;
    
    if ((_direction == CWDrawerTransitionFromRight && _type == CWDrawerTransitiontypeShow) || (_direction == CWDrawerTransitionFromLeft && _type == CWDrawerTransitiontypeHidden)) {
        _percent = -_percent;
    }

    switch (pan.state) {
        case UIGestureRecognizerStateBegan:
            break;
        case UIGestureRecognizerStateChanged: {
            if (!self.interacting) { // 保证present只调用一次
                if (_type == CWDrawerTransitiontypeShow) {
                    // 必须最少有20个位移才进行抽屉显示
                    if (fabs(x) > 20) [self showBeganTranslationX:x gesture:pan];
                }else {
                    [self hiddenBeganTranslationX:x];
                }
            }else {
                [self cw_updateInteractiveTransition];
            }
            break;
        }
        case UIGestureRecognizerStateCancelled:
        case UIGestureRecognizerStateEnded:{
            [self cw_endInteractiveTransition];
            break;
        }
        default:
            break;
    }
}

#pragma mark edge gesture
- (void)cw_handleEdgePan:(UIScreenEdgePanGestureRecognizer *)edgePan {
    if (_type == CWDrawerTransitiontypeHidden) return;
    
    CGFloat x = [edgePan translationInView:edgePan.view].x;
    _percent = 0;
    _percent = x / edgePan.view.frame.size.width;
    _direction = edgePan.edges == UIRectEdgeRight;
    if (_direction == CWDrawerTransitionFromRight) {
        _percent = -_percent;
    }
    switch (edgePan.state) {
        case UIGestureRecognizerStateBegan: {
            self.interacting = YES;
            if (_transitionDirectionAutoBlock) {
                _transitionDirectionAutoBlock(_direction);
            }
            break;
        }
        case UIGestureRecognizerStateChanged: {
            [self cw_updateInteractiveTransition];
            break;
        }
        case UIGestureRecognizerStateCancelled:
        case UIGestureRecognizerStateEnded:{
            [self cw_endInteractiveTransition];
            break;
        }
        default:
            break;
    }
}

- (void)startTimerAnimationWithFinishTransition:(BOOL)isFinish {
    if (isFinish && _percent >= 1) {
        [self finishInteractiveTransition];
        return;
    }else if (!isFinish && _percent <= 0) {
        [self cancelInteractiveTransition];
        return;
    }
    _toFinish = isFinish;
    CGFloat remainDuration = isFinish ? self.duration * (1 - _percent) : self.duration * _percent;
    _remaincount = 60 * remainDuration;
    _oncePercent = isFinish ? (1 - _percent) / _remaincount : _percent / _remaincount;
    [self starDisplayLink];
}

#pragma mark - displayerLink
- (void)starDisplayLink {
    [self link];
}

- (void)stopDisplayerLink {
    [self.link invalidate];
    self.link = nil;
}

- (void)cw_update {
    if (_percent >= 0.97 && _toFinish) {
        [self stopDisplayerLink];
        [self finishInteractiveTransition];
    }else if (_percent <= 0.03 && !_toFinish) {
        [self stopDisplayerLink];
        [self cancelInteractiveTransition];
    }else {
        if (_toFinish) {
            _percent += _oncePercent;
        }else {
            _percent -= _oncePercent;
        }
        CGFloat percent = fminf(fmaxf(_percent, 0.03), 0.97);
        [self updateInteractiveTransition:percent];
    }
}

- (void)dealloc {
    [[NSNotificationCenter defaultCenter] removeObserver:self];
}

#pragma mark - UIGestureRecognizerDelegate
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer {
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wundeclared-selector"
    SEL selector = @selector(cw_gestureRecognizer:shouldRecognizeSimultaneouslyWithGestureRecognizer:);
    if ([self.weakVC respondsToSelector:selector]) {
        IMP imp = [self.weakVC methodForSelector:selector];
        BOOL (*func)(id, SEL, UIGestureRecognizer *, UIGestureRecognizer *) = (void *)imp;
        BOOL result = func(self.weakVC, selector, gestureRecognizer, otherGestureRecognizer);
        return result;
    }
#pragma clang diagnostic pop
    // 没有实现对应方法直接走以下默认逻辑
    if ([[self viewController:otherGestureRecognizer.view] isKindOfClass:[UITableViewController class]]) {
        return YES;
    }
    return NO;
}



@end