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//
//  LNCustomCollectionViewController.h
//  LNMobileProject
//
//  Created by 六牛科技 on 2018/7/24.
//
//  山东六牛网络科技有限公司 https://liuniukeji.com
//

#import "LNBaseVC.h"

@interface LNCustomCollectionViewController : LNBaseVC

@property (strong, nonatomic) UICollectionView *collectionView;
@property (strong, nonatomic) NSMutableArray *dataArray;
@property (assign, nonatomic) NSInteger page;

- (void)loadData;
- (void)loadDataWithUrl:(NSString *)url params:(NSDictionary *)params success:(void(^)(id json))success;
- (void)reloadData;

@end

//
//  LNCustomCollectionViewController.m
//  LNMobileProject
//
//  Created by 六牛科技 on 2018/7/24.
//
//  山东六牛网络科技有限公司 https://liuniukeji.com
//

#import "LNCustomCollectionViewController.h"

@interface LNCustomCollectionViewController () <UICollectionViewDataSource, UICollectionViewDelegateFlowLayout>

@property (strong, nonatomic) EmptyDataSource *emptyDataSource;
@property (assign, nonatomic) BOOL isLoading;

@end

@implementation LNCustomCollectionViewController

- (NSMutableArray *)dataArray {
    if (!_dataArray) {
        _dataArray = [NSMutableArray new];
    }
    return _dataArray;
}

- (NSInteger)page {
    if (!_page) {
        _page = 1;
    }
    return _page;
}

- (EmptyDataSource *)emptyDataSource{
    if (!_emptyDataSource) {
        _emptyDataSource = [[EmptyDataSource alloc] init];
    }
    return _emptyDataSource;
}

- (void)viewDidLoad {
    [super viewDidLoad];

    UICollectionViewFlowLayout *layout = [UICollectionViewFlowLayout new];
    if (!self.collectionView) {
        UICollectionView *collectionView = [[UICollectionView alloc] initWithFrame:[[UIScreen mainScreen] bounds] collectionViewLayout:layout];
        collectionView.autoresizingMask = UIViewAutoresizingFlexibleHeight|UIViewAutoresizingFlexibleWidth;
        self.view = self.collectionView = collectionView;
    } else {
        self.collectionView.collectionViewLayout = layout;
    }

    self.collectionView.dataSource = self;
    self.collectionView.delegate = self;
    self.collectionView.emptyDataSetSource = self.emptyDataSource;
    self.collectionView.emptyDataType = EmptyDataTypeList;
    MJRefreshNormalHeader *header = [MJRefreshNormalHeader headerWithRefreshingBlock:^{
        [self reloadData];
    }];
    header.lastUpdatedTimeLabel.hidden = YES;
    self.collectionView.mj_header = header;
    self.collectionView.mj_footer = [MJRefreshBackNormalFooter footerWithRefreshingBlock:^{
        if (self.dataArray.count) {
            self.page++;
        } else {
            self.page = 1;
        }
        [self loadData];
    }];
}

- (void)reloadData {
    self.page = 1;
    [self loadData];
}

- (void)loadData {
    [self.dataArray addObject:[NSDate date].description];
    [self.collectionView reloadData];
    [self endRefresh];
}

- (void)endRefresh {
    [self.collectionView.mj_header endRefreshing];
    [self.collectionView.mj_footer endRefreshing];
}

- (void)loadDataWithUrl:(NSString *)url params:(NSDictionary *)params success:(void(^)(id json))success {
    if (self.isLoading) {
        return;
    }
    self.isLoading = YES;

    if (![self.collectionView.mj_header isRefreshing] && ![self.collectionView.mj_footer isRefreshing]) {
        [SVProgressHUD show];
    }
    [[[LNNetWorkAPI alloc] initWithUrl:url parameters:params] startWithBlockSuccess:^(__kindof LCBaseRequest *request) {
        self.isLoading = NO;
        [SVProgressHUD dismiss];
        [self endRefresh];
        
        if (self.page == 1) {
            [self.dataArray removeAllObjects];
        }

        id json = request.responseJSONObject;
        if ([json[@"status"] integerValue] != 1) {
            [SVProgressHUD showInfoWithStatus:json[@"msg"]];
            return;
        }
        if (self.page > 1 || ([json[@"data"] respondsToSelector:@selector(count)] && [json[@"data"] count])) {
            [self.collectionView removeEmptyDataSet];
        } else {
            [self.collectionView reloadEmptyDataSet];
        }
        if (success) {
            success(json);
        }
    } failure:^(__kindof LCBaseRequest *request, NSError *error) {
        self.isLoading = NO;
        [SVProgressHUD dismiss];
        [self endRefresh];
        [SVProgressHUD showInfoWithStatus:error.domain];
    }];
}

#pragma mark - Collection view

- (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView {
    return 1;
}

- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section {
    return self.dataArray.count;
}

- (UICollectionReusableView *)collectionView:(UICollectionView *)collectionView viewForSupplementaryElementOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath {
    if ([kind isEqualToString:UICollectionElementKindSectionHeader]) {
        UICollectionReusableView *view = [collectionView dequeueReusableSupplementaryViewOfKind:kind withReuseIdentifier:@"UICollectionReusableView" forIndexPath:indexPath];
        return view;
    }
    return nil;
}

- (__kindof UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath {
    UICollectionViewCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"UICollectionViewCell" forIndexPath:indexPath];
    return cell;
}

- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath {
    const NSInteger kItemNumOfRow = 3;
    UICollectionViewFlowLayout *layout = (UICollectionViewFlowLayout *)collectionViewLayout;
    NSInteger row = indexPath.row;
    CGFloat totalWidth = self.collectionView.frame.size.width - layout.sectionInset.left - layout.sectionInset.right - layout.minimumInteritemSpacing * (kItemNumOfRow - 1);
    CGFloat width;
    
    if (row % kItemNumOfRow) {
        width = roundf(totalWidth / kItemNumOfRow);
    } else {
        width = totalWidth - roundf(totalWidth / kItemNumOfRow) * (kItemNumOfRow - 1);
    }
    
    return CGSizeMake(width, width);
}

- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath {
}

@end