From 717237b1c31576d42cdfb9521839a026dc70b198 Mon Sep 17 00:00:00 2001
From: Khoren Markosyan <k.markosyan@gavrgroup.com>
Date: Tue, 13 Sep 2016 14:30:52 +0400
Subject: [PATCH] Implemented new autoscrolling logic.

---
 .../iCarouselExampleViewController.m          |  7 ++
 iCarousel/iCarousel.h                         | 13 +++
 iCarousel/iCarousel.m                         | 89 ++++++++++++++++++-
 3 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/Examples/Basic iOS Example/iCarouselExampleViewController.m b/Examples/Basic iOS Example/iCarouselExampleViewController.m
index 1d70d95ba9..022fdaa533 100644
--- a/Examples/Basic iOS Example/iCarouselExampleViewController.m	
+++ b/Examples/Basic iOS Example/iCarouselExampleViewController.m	
@@ -53,6 +53,13 @@ - (void)viewDidLoad
     _carousel.type = iCarouselTypeCoverFlow2;
 }
 
+-(void)viewDidAppear:(BOOL)animated {
+    [super viewDidAppear:animated];
+
+    // Uncomment this line for testing autoscrolling.
+//    [_carousel start];
+}
+
 - (void)viewDidUnload
 {
     [super viewDidUnload];
diff --git a/iCarousel/iCarousel.h b/iCarousel/iCarousel.h
index d49c268203..3a037b5643 100644
--- a/iCarousel/iCarousel.h
+++ b/iCarousel/iCarousel.h
@@ -141,6 +141,7 @@ NS_ASSUME_NONNULL_BEGIN
 @property (nonatomic, readonly, getter = isDragging) BOOL dragging;
 @property (nonatomic, readonly, getter = isDecelerating) BOOL decelerating;
 @property (nonatomic, readonly, getter = isScrolling) BOOL scrolling;
+@property (nonatomic, assign) CGFloat autoscrollDelay;
 
 - (void)scrollByOffset:(CGFloat)offset duration:(NSTimeInterval)duration;
 - (void)scrollToOffset:(CGFloat)offset duration:(NSTimeInterval)duration;
@@ -158,6 +159,12 @@ NS_ASSUME_NONNULL_BEGIN
 - (void)insertItemAtIndex:(NSInteger)index animated:(BOOL)animated;
 - (void)reloadItemAtIndex:(NSInteger)index animated:(BOOL)animated;
 
+// Autoscroll methods
+- (void)start;
+- (void)stop;
+- (void)previous;
+- (void)next;
+
 - (void)reloadData;
 
 @end
@@ -195,6 +202,12 @@ NS_ASSUME_NONNULL_BEGIN
 - (CATransform3D)carousel:(iCarousel *)carousel itemTransformForOffset:(CGFloat)offset baseTransform:(CATransform3D)transform;
 - (CGFloat)carousel:(iCarousel *)carousel valueForOption:(iCarouselOption)option withDefault:(CGFloat)value;
 
+// Autoscroll delegates
+- (void)carouselDidShowNext:(iCarousel *)carousel;
+- (void)carouselDidShowPrevious:(iCarousel *)carousel;
+- (void)carouselWillShowNext:(iCarousel *)carousel;
+- (void)carouselWillShowPrevious:(iCarousel *)carousel;
+
 @end
 
 NS_ASSUME_NONNULL_END
diff --git a/iCarousel/iCarousel.m b/iCarousel/iCarousel.m
index 707874a83a..19dcf6b3d4 100644
--- a/iCarousel/iCarousel.m
+++ b/iCarousel/iCarousel.m
@@ -122,6 +122,9 @@ @interface iCarousel ()
 @property (nonatomic, assign) BOOL didDrag;
 @property (nonatomic, assign) NSTimeInterval toggleTime;
 
+@property (atomic) BOOL doStop;
+@property (atomic) BOOL isAnimating;
+
 NSComparisonResult compareViewDepth(UIView *view1, UIView *view2, iCarousel *self);
 
 @end
@@ -147,7 +150,11 @@ - (void)setUp
     _scrollToItemBoundary = YES;
     _ignorePerpendicularSwipes = YES;
     _centerItemWhenSelected = YES;
-    
+
+    _doStop = YES;
+    _isAnimating = NO;
+    _autoscrollDelay = 2;
+
     _contentView = [[UIView alloc] initWithFrame:self.bounds];
     
     
@@ -1768,6 +1775,13 @@ - (void)step
             [self pushAnimationState:YES];
             [_delegate carouselDidEndScrollingAnimation:self];
             [self popAnimationState];
+
+            _isAnimating = NO;
+
+            if (!_doStop) {
+                [NSObject cancelPreviousPerformRequestsWithTarget:self selector:@selector(next) object:nil];
+                [self performSelector:@selector(next) withObject:nil afterDelay:_autoscrollDelay];
+            }
         }
     }
     else if (_decelerating)
@@ -2341,4 +2355,77 @@ - (void)keyDown:(NSEvent *)theEvent
 
 #endif
 
+
+#pragma mark - Autoscroll methods
+
+- (void)start
+{
+    _doStop = NO;
+    [self next];
+}
+
+- (void)stop
+{
+    _doStop = YES;
+    [NSObject cancelPreviousPerformRequestsWithTarget:self selector:@selector(next) object:nil];
+}
+
+- (void)next
+{
+    if (!_isAnimating && (self.dataSource && _numberOfItems >1)) {
+
+        if ([self.delegate respondsToSelector:@selector(carouselWillShowNext:)]) {
+            [self.delegate carouselWillShowNext:self];
+        }
+
+        // Next Image
+        NSUInteger nextIndex = (self.currentItemIndex+1) % _numberOfItems;
+
+        // Animate
+        [self scrollToItemAtIndex:nextIndex animated:YES];
+
+        // Call delegate
+        if([self.delegate respondsToSelector:@selector(carouselDidShowNext:)]){
+            dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, SCROLL_DURATION * NSEC_PER_SEC);
+            dispatch_after(popTime, dispatch_get_main_queue(), ^(void){
+                if (self.window){
+                    [self.delegate carouselDidShowNext:self];
+                }
+            });
+        }
+    }
+}
+
+- (void)previous
+{
+    if (!_isAnimating && (self.dataSource && _numberOfItems >1)) {
+
+        if ([self.delegate respondsToSelector:@selector(carouselWillShowPrevious:)]) {
+            [self.delegate carouselWillShowPrevious:self];
+        }
+
+        // Previous image
+        NSUInteger prevIndex;
+        if (self.currentItemIndex == 0){
+            prevIndex = _numberOfItems - 1;
+        } else {
+            prevIndex = (self.currentItemIndex - 1) % _numberOfItems;
+        }
+
+        // Animate
+        [self scrollToItemAtIndex:prevIndex animated:YES];
+
+        // Call delegate
+        if ([self.delegate respondsToSelector:@selector(carouselDidShowPrevious:)]) {
+            dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, SCROLL_DURATION * NSEC_PER_SEC);
+            dispatch_after(popTime, dispatch_get_main_queue(), ^(void) {
+                if (self.window) {
+                    [self.delegate carouselDidShowPrevious:self];
+                }
+            });
+        }
+    }
+    
+}
+
 @end