JSJP_Student/jiaPei/Modules/BaseModule/BaseClass/ViewController/RQCollectionViewController.m

//
//  RQCollectionViewController.m
//  YueXueChe
//
//  Created by 张嵘 on 2018/12/18.
//  Copyright © 2018 lee. All rights reserved.
//

#import "RQCollectionViewController.h"

@interface RQCollectionViewController ()
/// collectionView
@property (nonatomic, readwrite, weak) RQCollectionView *collectionView;
/// contentInset defaul is (64 , 0 , 0 , 0)
@property (nonatomic, readwrite, assign) UIEdgeInsets contentInset;
/// 视图模型
@property (nonatomic, readonly, strong) RQCollectionViewModel *viewModel;

@property (nonatomic, readwrite, strong) UICollectionViewFlowLayout *flowLayout;
@end

@implementation RQCollectionViewController
@dynamic viewModel;

- (void)dealloc {
	// set nil
	_collectionView.dataSource = nil;
	_collectionView.delegate = nil;
}

/// init
- (instancetype)initWithViewModel:(RQCollectionViewModel *)viewModel {
	self = [super initWithViewModel:viewModel];
	if (self) {
		if ([viewModel shouldRequestRemoteDataOnViewDidLoad]) {
			@weakify(self)
			[[self rac_signalForSelector:@selector(viewDidLoad)] subscribeNext:^(id x) {
				@strongify(self)
				/// 请求第一页的网络数据
				[self.viewModel.requestRemoteDataCommand execute:@1];
			}];
		}
	}
	return self;
}


- (void)viewDidLoad {
	[super viewDidLoad];
	// 设置子控件
	[self _su_setupSubViews];
	
}

/// override
- (void)bindViewModel {
	[super bindViewModel];
	
	/// observe viewModel's dataSource
	@weakify(self)
	NSLog(@"%@", self.viewModel.dataSource);
	[[RACObserve(self.viewModel, dataSource)
	  deliverOnMainThread]
	 subscribeNext:^(id x) {
		 @strongify(self)
		 // 刷新数据
		 [self reloadData];
	 }];
	
	/// 隐藏emptyView
	[self.viewModel.requestRemoteDataCommand.executing subscribeNext:^(NSNumber *executing) {
		@strongify(self)
		UIView *emptyDataSetView = [self.collectionView.subviews.rac_sequence objectPassingTest:^(UIView *view) {
			return [NSStringFromClass(view.class) isEqualToString:@"DZNEmptyDataSetView"];
		}];
		emptyDataSetView.alpha = 1.0 - executing.floatValue;
	}];
	
	
	//    [self.viewModel.requestRemoteDataCommand.executionSignals.switchToLatest subscribeNext:^(id _) {
	//        @strongify(self);
	//        /// 有网络
	//        self.viewModel.disableNetwork = NO;
	//    }];
	//
	//    [self.viewModel.requestRemoteDataCommand.errors subscribeNext:^(id _) {
	//        @strongify(self);
	//        /// 有无网络
	//        self.viewModel.disableNetwork = !self.viewModel.services.client.reachabilityManager.reachable;
	//    }];
}

#pragma mark - 设置子控件
/// setup add `_su_` avoid sub class override it
- (void)_su_setupSubViews{
	// set up tableView
	/// RQ FIXED: 纯代码布局，子类如果重新布局，建议用Masonry重新设置约束
	// 创建布局对象
    _flowLayout = [[UICollectionViewFlowLayout alloc] init];
	// 设置最小行间距
    _flowLayout.minimumLineSpacing = 8;
	// 最小列间距
    _flowLayout.minimumInteritemSpacing = 8;
	/**
	 *   设置item的大小 格局item的大小自动布局列间距
	 *
	 *  @param 50 宽
	 *  @param 50 高
	 *
	 *  @return
	 */
    _flowLayout.itemSize = CGSizeMake(0, 0);
	/**
	 *  设置自动滚动的方向 垂直或者横向
	 */
    _flowLayout.scrollDirection = UICollectionViewScrollDirectionVertical;
	/**
	 *  设置集合视图内边距的大小
	 *
	 *  @param 20 上
	 *  @param 20 左
	 *  @param 20 下
	 *  @param 20 右
	 *
	 *  @return  UIEdgeInsetsMake  与下面的方法相同  -(UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout insetForSectionAtIndex:(NSInteger)section
	 */
    _flowLayout.sectionInset = UIEdgeInsetsMake(16, 16, 16, 16);
	/**
	 *  设置header区域大小
	 *
	 *  @param 414 414
	 *  @param 70  无用
	 *
	 *  @return
	 */
    _flowLayout.headerReferenceSize = CGSizeMake(RQ_SCREEN_WIDTH, 40);
	/**
	 *  设置footer区域的大小
	 *
	 *  @param 414 无用
	 *  @param 70  自己设置
	 *
	 *  @return  如果写了这里必须设置注册
	 */
    _flowLayout.footerReferenceSize = CGSizeMake(RQ_SCREEN_WIDTH, 10);
	
	/**
	 创建UICollectionView前必须先创建布局对象UICollectionViewFlowLayout
	 
	 - returns: UICollectionViewFlowLayout(布局对象)
	 */
	RQCollectionView *collectionView = [[RQCollectionView alloc] initWithFrame:[UIScreen mainScreen].bounds collectionViewLayout:_flowLayout];
	collectionView.backgroundColor = RQ_MAIN_BACKGROUNDCOLOR;
	collectionView.showsVerticalScrollIndicator = NO;
	collectionView.showsHorizontalScrollIndicator = NO;
	collectionView.delegate = self;
	collectionView.dataSource = self;
	collectionView.bounces = YES;
	collectionView.delaysContentTouches = false;
	[self.view addSubview:collectionView];
	
	/// 占位符
	//    tableView.emptyDataSetDelegate = self;
	//    tableView.emptyDataSetSource = self;
	//    [tableView mas_makeConstraints:^(MASConstraintMaker *make) {
	//        make.edges.mas_equalTo(UIEdgeInsetsZero);
	//    }];
	
	
	self.collectionView = collectionView;
	collectionView.contentInset = self.contentInset;
	
	// 注册cell
	[self.collectionView registerClass:[UICollectionViewCell class] forCellWithReuseIdentifier:@"UICollectionViewCell"];
	
	
	/// RQ-MARK: 这里需要强制布局一下界面，解决由于设置了collectionView的contentInset，然而contentOffset始终是（0，0）的bug 但是这样会导致 collectionView 刷新一次，从而导致子类在 viewDidLoad 无法及时注册的cell，从而会有Crash的隐患
	//        [self.collectionView layoutIfNeeded];
	//        [self.collectionView setNeedsLayout];
	//        [self.collectionView updateConstraintsIfNeeded];
	//        [self.collectionView setNeedsUpdateConstraints];
	//        [self.view layoutIfNeeded];
	
	/// 添加加载和刷新控件
	if (self.viewModel.shouldPullDownToRefresh) {
		/// 下拉刷新
		@weakify(self);
		[self.collectionView rq_addHeaderRefresh:^(MJRefreshNormalHeader *header) {
			/// 加载下拉刷新的数据
			@strongify(self);
			[self tableViewDidTriggerHeaderRefresh];
		}];
		[self.collectionView.mj_header beginRefreshing];
	}
	
	if (self.viewModel.shouldPullUpToLoadMore) {
		/// 上拉加载
		@weakify(self);
		[self.collectionView rq_addFooterRefresh:^(MJRefreshAutoNormalFooter *footer) {
			/// 加载上拉刷新的数据
			@strongify(self);
			[self tableViewDidTriggerFooterRefresh];
		}];
		
		/// 隐藏footer or 无更多数据
		RAC(self.collectionView.mj_footer, hidden) = [[RACObserve(self.viewModel, dataSource)
												  deliverOnMainThread]
												 map:^(NSArray *dataSource) {
													 @strongify(self)
													 NSUInteger count = dataSource.count;
													 /// 无数据，默认隐藏mj_footer
													 if (count == 0) return @1;
													 
													 if (self.viewModel.shouldEndRefreshingWithNoMoreData) return @(0);
													 
													 /// because of
													 return (count % self.viewModel.perPage)?@1:@0;
												 }];
		
	}
	
	
	if (@available(iOS 11.0, *)) {
		/// RQ: 适配 iPhone X + iOS 11，
		RQAdjustsScrollViewInsets_Never(collectionView);
	}
}

#pragma mark - 上下拉刷新事件
/// 下拉事件
- (void)tableViewDidTriggerHeaderRefresh{
	@weakify(self)
	[[[self.viewModel.requestRemoteDataCommand
	   execute:@1]
	  deliverOnMainThread]
	 subscribeNext:^(id x) {
		 @strongify(self)
		 self.viewModel.page = 1;
		 /// 重置没有更多的状态
		 if (self.viewModel.shouldEndRefreshingWithNoMoreData) [self.collectionView.mj_footer resetNoMoreData];
	 } error:^(NSError *error) {
		 @strongify(self)
		 /// 已经在bindViewModel中添加了对viewModel.dataSource的变化的监听来刷新数据,所以reload = NO即可
		 [self.collectionView.mj_header endRefreshing];
	 } completed:^{
		 @strongify(self)
		 /// 已经在bindViewModel中添加了对viewModel.dataSource的变化的监听来刷新数据,所以只要结束刷新即可
		 [self.collectionView.mj_header endRefreshing];
		 /// 请求完成
		 [self _requestDataCompleted];
	 }];
}

/// 上拉事件
- (void)tableViewDidTriggerFooterRefresh{
	@weakify(self);
	[[[self.viewModel.requestRemoteDataCommand
	   execute:@(self.viewModel.page + 1)]
	  deliverOnMainThread]
	 subscribeNext:^(id x) {
		 @strongify(self)
		 self.viewModel.page += 1;
	 } error:^(NSError *error) {
		 @strongify(self);
		 [self.collectionView.mj_footer endRefreshing];
	 } completed:^{
		 @strongify(self)
		 [self.collectionView.mj_footer endRefreshing];
		 /// 请求完成
		 [self _requestDataCompleted];
	 }];
}


#pragma mark - sub class can override it
- (UIEdgeInsets)contentInset{
	return UIEdgeInsetsMake((RQ_APPLICATION_NAV_BAR_HEIGHT + RQ_APPLICATION_STATUS_BAR_HEIGHT), 0, 0, 0);
}

/// reload tableView data
- (void)reloadData{
	[self.collectionView reloadData];
}

/// duqueueReusavleCell
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView dequeueReusableCellWithIdentifier:(NSString *)identifier forIndexPath:(NSIndexPath *)indexPath {
	return [collectionView dequeueReusableCellWithReuseIdentifier:identifier forIndexPath:indexPath];
}

/// configure cell data
- (void)configureCell:(UICollectionViewCell *)cell atIndexPath:(NSIndexPath *)indexPath withObject:(id)object {
	
}

#pragma mark - 辅助方法
- (void)_requestDataCompleted{
	NSUInteger count = self.viewModel.dataSource.count;
	/// RQ Fixed: 这里必须要等到，底部控件结束刷新后，再来设置无更多数据，否则被叠加无效
	if (self.viewModel.shouldEndRefreshingWithNoMoreData && count%self.viewModel.perPage) [self.collectionView.mj_footer endRefreshingWithNoMoreData];
}


#pragma mark - UICollectionViewDatasource
- (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView {
	if (self.viewModel.shouldMultiSections) return self.viewModel.dataSource ? self.viewModel.dataSource.count : 0;
	return 1;
}

- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section {
	if (self.viewModel.shouldMultiSections) return [(NSArray *)self.viewModel.dataSource[section] count];
	return self.viewModel.dataSource.count;
}

- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath {
	UICollectionViewCell *cell = [self collectionView:collectionView dequeueReusableCellWithIdentifier:@"UICollectionViewCell" forIndexPath:indexPath];
	
	// fetch object
	id object = nil;
	if (self.viewModel.shouldMultiSections) object = self.viewModel.dataSource[indexPath.section][indexPath.row];
	if (!self.viewModel.shouldMultiSections) object = self.viewModel.dataSource[indexPath.row];
	
	/// bind model
	[self configureCell:cell atIndexPath:indexPath withObject:(id)object];
	return cell;
}


#pragma mark - UICollectionViewDelegate
- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath {
	[collectionView deselectItemAtIndexPath:indexPath animated:YES];
	// execute commond
	[self.viewModel.didSelectCommand execute:indexPath];
}

#pragma mark - collectionViewCell点击高亮
- (void)collectionView:(UICollectionView *)collectionView didHighlightItemAtIndexPath:(NSIndexPath *)indexPath{
//	UICollectionViewCell *cell = [collectionView cellForItemAtIndexPath:indexPath];
}
- (void)collectionView:(UICollectionView *)collectionView didUnhighlightItemAtIndexPath:(NSIndexPath *)indexPath{
	
//	UICollectionViewCell *cell = [collectionView cellForItemAtIndexPath:indexPath];
//	cell.backgroundColor = [UIColor whiteColor];
}
- (BOOL)collectionView:(UICollectionView *)collectionView shouldHighlightItemAtIndexPath:(NSIndexPath *)indexPath{
	
	return YES;
}


@end