erpsuiteios/common/customUI/PhotoList/Controller/ContentPreviewController.m

//
//  NewPhotoPreviewController.m
//  RA Image
//
//  Created by Jack on 2017/6/14.
//  Copyright © 2017年 USAI. All rights reserved.
//

#import "ContentPreviewController.h"
#import "PhotoPreviewCell.h"
#import "VideoPreviewCell.h"
#import "AppDelegate.h"
#import "FileCache.h"

@interface ContentPreviewController ()<UICollectionViewDelegate,UICollectionViewDataSource,UICollectionViewDelegateFlowLayout>

@property (nonatomic,assign) NSUInteger currentIndex;
@property (strong, nonatomic) IBOutlet UILabel *indicator;
@property (strong, nonatomic) IBOutlet UICollectionView *previewContainer;

@property (nonatomic,strong) NSArray *photos;

@property (nonatomic,strong) UIView *mask;

@property (nonatomic,assign) BOOL hideNavigationBar;

@end

@implementation ContentPreviewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
//    self.automaticallyAdjustsScrollViewInsets = NO;
//    self.navigationController.navigationBar.translucent = NO;
//    self.edgesForExtendedLayout = UIRectEdgeNone;

    UIView *v = [UIView new];
    [self.view insertSubview:v atIndex:0];
    
    NSMutableArray *tmpArr = [NSMutableArray array];
    int count = [[self.content objectForKey:@"count"] intValue];
    for (int i = 0; i < count; i++) {
        NSDictionary *item = [self.content objectForKey:[NSString stringWithFormat:@"item_%d",i]];
        [tmpArr addObject:item];
    }
    self.photos = [tmpArr copy];
    
    self.indicator.layer.cornerRadius = 20;
    self.indicator.layer.masksToBounds = YES;
    
    self.previewContainer.pagingEnabled = YES;
    NSString *offset = [NSString stringWithFormat:@"%lu / %lu",(unsigned long)self.currentIndex + 1,(unsigned long)self.photos.count];
    self.indicator.text = offset;
   
    
    
    self.hideNavigationBar = self.navigationController.isNavigationBarHidden;
    
    self.navigationController.navigationBarHidden = YES;
    
    // 掩藏滚动
    [self.view insertSubview:self.mask belowSubview:self.indicator];
}

- (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];
}

- (void)viewDidLayoutSubviews {
    [super viewDidLayoutSubviews];

    
//    if (self.currentIndex > 0) {
//        [self.previewContainer scrollToItemAtIndexPath:[NSIndexPath indexPathForItem:self.currentIndex inSection:0] atScrollPosition:16 animated:YES];
//    }
    
//    [self scrollToIndex:self.currentIndex + 1];
   [self.previewContainer setContentOffset:CGPointMake((self.currentIndex + 1) * CGRectGetWidth(self.previewContainer.frame), 0) animated:YES];

}

- (void)viewDidAppear:(BOOL)animated {
    [super viewDidAppear:animated];
    
//    [self.previewContainer scrollToItemAtIndexPath:[NSIndexPath indexPathForItem:self.currentIndex inSection:0] atScrollPosition:16 animated:YES];
    
    __weak typeof(self) weakself = self;
    dispatch_async(dispatch_get_global_queue(0, 0), ^{
        sleep(0.25);
        dispatch_async(dispatch_get_main_queue(), ^{
            [weakself.mask removeFromSuperview];
            weakself.mask = nil;
        });

    });
}


- (void)viewWillTransitionToSize:(CGSize)size withTransitionCoordinator:(id<UIViewControllerTransitionCoordinator>)coordinator {
    [super viewWillTransitionToSize:size withTransitionCoordinator:coordinator];
    [coordinator animateAlongsideTransition:^(id<UIViewControllerTransitionCoordinatorContext>  _Nonnull context) {
        // what ever you want to prepare
    } completion:^(id<UIViewControllerTransitionCoordinatorContext>  _Nonnull context) {
        [self.previewContainer.collectionViewLayout invalidateLayout];
    }];
}
//- (void)willAnimateRotationToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration {
//    
//    // 重新布局 Item 大小
//    [self.previewContainer.collectionViewLayout invalidateLayout];
//
//    // 重新布局Item位置
////    [self.previewContainer scrollToItemAtIndexPath:[NSIndexPath indexPathForItem:self.currentIndex inSection:0] atScrollPosition:32 animated:NO];
////    [self scrollToIndex:self.currentIndex + 1];
//}

- (BOOL)prefersStatusBarHidden {
    return YES;
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

- (UIView *)mask {
    if (!_mask) {
        _mask = [[UIView alloc] initWithFrame:self.view.bounds];
        _mask.backgroundColor = [UIColor blackColor];
    }
    return _mask;
}


#pragma mark - Setter

- (void)setOffset:(NSUInteger)offset {
    [self setCurrentIndex:offset];
}

//- (void)setCurrentIndex:(NSUInteger)currentIndex {
//    _currentIndex = currentIndex;
//    NSString *offset = [NSString stringWithFormat:@"%lu / %lu",(unsigned long)self.currentIndex + 1,(unsigned long)self.photos.count];
//    self.indicator.text = offset;
//}

#pragma mark - FlowLayout Delegate

- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath {
    return collectionView.bounds.size;
}

- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout minimumLineSpacingForSectionAtIndex:(NSInteger)section {
    return 0;
}

- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout minimumInteritemSpacingForSectionAtIndex:(NSInteger)section {
    return 0;
}

- (UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout insetForSectionAtIndex:(NSInteger)section {
    return UIEdgeInsetsZero;
}

#pragma mark - CollectionView Delegate

- (void)collectionView:(UICollectionView *)collectionView willDisplayCell:(UICollectionViewCell *)cell forItemAtIndexPath:(NSIndexPath *)indexPath {

    
    
    NSUInteger idx = [self contentOffsetForIndexPath:indexPath];
    NSDictionary *item = [self.photos objectAtIndex:idx];
    NSString *type = [item objectForKey:@"type"];
    
    if ([type isEqualToString:@"image"]) {
        PhotoPreviewCell *preCell = (PhotoPreviewCell *)cell;
        
        [self photoCell:preCell loadImage:item];
        

        
    } else if ([type isEqualToString:@"video"]) {
        
        VideoPreviewCell *videoCell = (VideoPreviewCell *)cell;
        videoCell.item = item;

        
    }
}

- (void)collectionView:(UICollectionView *)collectionView didEndDisplayingCell:(UICollectionViewCell *)cell forItemAtIndexPath:(NSIndexPath *)indexPath {
    
    NSUInteger idx = [self contentOffsetForIndexPath:indexPath];
    NSDictionary *item = [self.photos objectAtIndex:idx];
    NSString *type = [item objectForKey:@"type"];
    
    if ([type isEqualToString:@"image"]) {
        PhotoPreviewCell *preCell = (PhotoPreviewCell *)cell;
        UIScrollView *sc = preCell.scrollView;
        sc.zoomScale = 1;
        sc.contentSize = CGSizeZero;
        sc.contentOffset = CGPointZero;
    } else if ([type isEqualToString:@"video"]) {
        
        VideoPreviewCell *videoCell = (VideoPreviewCell *)cell;

        [videoCell reset];
    }
}

- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath {
    
    NSUInteger idx = [self contentOffsetForIndexPath:indexPath];
    NSDictionary *item = [self.photos objectAtIndex:idx];
    NSString *type = [item objectForKey:@"type"];
    
    if ([type isEqualToString:@"video"]) {
        
        VideoPreviewCell *videoCell = (VideoPreviewCell *)[collectionView cellForItemAtIndexPath:indexPath];
        
        [videoCell play];
    }
}


#pragma mark - CollectionView DataSource

- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section {
    if ([self.photos count] == 0) {
        return 0;
    }
    return self.photos.count + 2;
}

- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath {
    
    NSUInteger idx = [self contentOffsetForIndexPath:indexPath];
    
    NSDictionary *item = [self.photos objectAtIndex:idx];
    NSString *type = [item objectForKey:@"type"];
    
    if ([type isEqualToString:@"image"]) {
        
        PhotoPreviewCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"PhotoPreviewCell" forIndexPath:indexPath];
        cell.scrollView.delegate = self;
        return cell;
        
    } else if ([type isEqualToString:@"video"]) {
        
        VideoPreviewCell *videoCell = [collectionView dequeueReusableCellWithReuseIdentifier:@"VideoPreviewCell" forIndexPath:indexPath];

        return videoCell;
    }
    
    return nil;
}

#pragma mark - ScrollView Delegate

- (void)scrollViewDidScroll:(UIScrollView *)scrollView {
//    if (scrollView == self.previewContainer) {
//
//        CGFloat x = scrollView.contentOffset.x / scrollView.frame.size.width;
//        int idx = (int)x;
//        if (idx == x) {
//            if (self.currentIndex != idx) {
//                self.currentIndex = idx;
//                
//            }
//        }
//    }
}

- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView {
    CGFloat offsetX = scrollView.contentOffset.x;
    float idxf = offsetX / CGRectGetWidth(scrollView.frame);
    int idxi = (int)(offsetX / CGRectGetWidth(scrollView.frame));
    
    if (idxf == idxi) {
        if (idxi == 0) {
            self.currentIndex = self.photos.count - 1;
        } else if (idxi == self.photos.count + 1) {
            self.currentIndex = 0;
        } else {
            self.currentIndex = idxi - 1;
        }
        
//        if (self.indicator) {
//            self.indicator(self.currentIndex, self.photos.count);
//        }
        [self updateIndicator];
    } else {
//        idxi = ceil(idxf);
//        if (idxi != 0 || idxi != self.photos.count + 1) {
//            [self scrollToIndex:idxi];
//        }
    }
    
    if (idxi == 0) {
        [self scrollToIndex:self.photos.count];
    }
    
    if (idxi == self.photos.count + 1) {
        [self scrollToIndex:1];
    }
    
}

- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView {
    if (scrollView != self.previewContainer) {
        return scrollView.subviews.firstObject;
    }
    return nil;
}

- (void)scrollViewDidZoom:(UIScrollView *)scrollView {
    
    if (self.previewContainer != scrollView) {
        

    }
}

#pragma mark - Private

- (void)updateIndicator {
    NSString *offset = [NSString stringWithFormat:@"%lu / %lu",(unsigned long)self.currentIndex + 1,(unsigned long)self.photos.count];
    self.indicator.text = offset;
}

- (NSUInteger)contentOffsetForIndexPath:(NSIndexPath *)indexPath {
    NSUInteger idx = indexPath.row;
    if (idx == 0) {
        idx = self.photos.count - 1;
    }else if (idx == self.photos.count + 1) {
        idx = 0;
    } else {
        idx = idx - 1;
    }
    return idx;
}

- (void)scrollToIndex:(NSUInteger)index { // 不会出现肉眼可见的滚动效果
    self.previewContainer.contentOffset = CGPointMake(index * CGRectGetWidth(self.previewContainer.frame), 0);
}

- (void) photoCell:(PhotoPreviewCell *)cell loadImage:(NSDictionary *)item_json {
    
    dispatch_async(dispatch_get_global_queue(0, 0), ^{
       
        
        
        NSString* img_url = [item_json valueForKey:@"s"];
        NSString* type = item_json[@"type"];
        
        NSString* file_name=[img_url lastPathComponent];
        NSData* img_data=nil;
        
        //  加载Image
        if([type isEqualToString:@"video"])
        {
            img_data = UIImagePNGRepresentation([UIImage imageNamed:@"play"]);
        }
        else
        {
            if([item_json[@"is_localfile"] boolValue])
                img_data = [NSData dataWithContentsOfFile:img_url];
            else
                img_data = [FileCache load_cached_img:file_name loadFrom:img_url];
        }
        
        // 设置Image
        if(img_data!=nil)
        {
            dispatch_async(dispatch_get_main_queue(), ^{
                UIImage * img =[UIImage imageWithData:img_data];
                
                [cell setPhoto:img];
                
            });
        }
        else
        {
            NSData*  downloadimg_data = nil;
            BOOL offline_mode = NO;
#ifdef OFFLINE_MODE
            AppDelegate *appDelegate = (AppDelegate *)[UIApplication sharedApplication].delegate;
            offline_mode = appDelegate.offline_mode;
#endif
            if (!offline_mode) {
                downloadimg_data = [NSData dataWithContentsOfURL:[NSURL URLWithString:img_url]];
            }
            dispatch_async(dispatch_get_main_queue(), ^{
                
                
                
                if(downloadimg_data!=nil)
                {
                    
                    [FileCache cache_img:downloadimg_data filename:file_name saveTo:img_url];
                    
                    UIImage * img =[UIImage imageWithData:downloadimg_data];
                    [cell setPhoto:img];
                    
                    
                }
                else
                {
                    
                    
                    UIImage * img =[UIImage imageNamed:@"notfound_l"];
                    [cell setPhoto:img];
                    
                    
                }
                
            });
        }
        
    });
    
}

- (IBAction)closeBtnClick:(UIButton *)sender {
    
    if (self.navigationController) {
        self.navigationController.navigationBarHidden = self.hideNavigationBar;
        [self.navigationController popViewControllerAnimated:YES];
    } else {
        [self dismissViewControllerAnimated:YES completion:nil];
    }
    
}


@end