'''
//
// GridViewController.m
// VTMagicView
//
// Created by tianzhuo on 14/12/30.
// Copyright (c) 2014年 tianzhuo. All rights reserved.
//

import "VTGridViewController.h"

import "VTDetailViewController.h"

import <VTMagic/VTMagic.h>

import "VTGridViewCell.h"

import "DataManager.h"

define IPHONELESS6 ([UIScreen instancesRespondToSelector:@selector(currentMode)] ? 640 == [[UIScreen mainScreen] currentMode].size.width : NO)

static NSString *reuseIdentifier = @"grid.reuse.identifier";

@interface VTGridViewController()

@property (nonatomic, strong) NSMutableArray *infoList;

@end

@implementation VTGridViewController

• (instancetype)init {
  // 1. 是iPhone设备 mark byKing
  BOOL iPhoneDevice = kiPhoneDevice;
  UICollectionViewFlowLayout *layout = [[UICollectionViewFlowLayout alloc] init];
  layout.scrollDirection = UICollectionViewScrollDirectionVertical;
  layout.sectionInset = iPhoneDevice ?UIEdgeInsetsMake(10, 10, 10, 10) : UIEdgeInsetsMake(20, 20, 20, 20);
  layout.itemSize = iPhoneDevice ? (IPHONELESS6 ? CGSizeMake(140, 175) : CGSizeMake(115, 170)) : CGSizeMake(188, 188);
  layout.minimumInteritemSpacing = iPhoneDevice ? 2 : 11;
  layout.minimumLineSpacing = iPhoneDevice ? 10 : 11;
  // collecitonVC默认初始方法 mark byKing
  return [super initWithCollectionViewLayout:layout];
  }

• (void)viewDidLoad {
  [super viewDidLoad];

  // ??? 为啥scrollsToTop = NO 还是会滚动. 视图显示的时候重新设置为YES
  self.collectionView.scrollsToTop = NO;
  self.collectionView.backgroundColor = RGBCOLOR(239, 239, 239);
  self.collectionView.contentInset = UIEdgeInsetsMake(0, 0, VTTABBAR_HEIGHT, 0);
  [self.collectionView registerClass:[VTGridViewCell class] forCellWithReuseIdentifier:reuseIdentifier];
  }

// 复用情况步骤分析: >>> 1.viewWillAppear

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

  VTPRINT_METHOD
  }
  // 复用情况步骤分析: >>> 2.viewDidAppear

• (void)viewDidAppear:(BOOL)animated {
  [super viewDidAppear:animated];

  [self refreshPageIfNeeded];
  self.collectionView.scrollsToTop = YES;
  NSInteger pageIndex = [self vtm_pageIndex];
  NSLog(@"current page index is: %ld", (long)pageIndex);
  VTPRINT_METHOD
  }

• (void)viewWillDisappear:(BOOL)animated {
  [super viewWillDisappear:animated];

  [self cancelNetworkRequest];
  self.collectionView.scrollsToTop = NO;
  VTPRINT_METHOD
  }

• (void)viewDidDisappear:(BOOL)animated {
  [super viewDidDisappear:animated];

  [self savePageInfo];
  VTPRINT_METHOD
  }

pragma mark UICollectionViewDataSource

• (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section {
  return _infoList.count;
  }

• (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath {
  VTGridViewCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:reuseIdentifier forIndexPath:indexPath];
  cell.backgroundColor = [UIColor whiteColor];
  NSString *imageName = _infoList[indexPath.item];
  [cell.imageView setImage:[UIImage imageNamed:imageName]];
  cell.commentLabel.text = [NSString stringWithFormat:@"%d人出游", arc4random_uniform(9999)];
  cell.titleLabel.text = @"景点介绍，景点介绍，景点介绍。。";
  return cell;
  }

• (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath {
  NSInteger currentPage = self.magicController.currentPage;
  NSLog(@"==didSelectItemAtIndexPath%@ \n current page is: %ld==", indexPath, (long)currentPage);
  VTDetailViewController *detailViewController = [[VTDetailViewController alloc] init];
  detailViewController.hidesBottomBarWhenPushed = YES;
  [self.navigationController pushViewController:detailViewController animated:YES];
  }

pragma mark - VTMagicReuseProtocol

• (void)vtm_prepareForReuse {
  // reset content offset
  NSLog(@"clear old data if needed:%@", self);
  [_infoList removeAllObjects];
  [self.collectionView reloadData];
  [self.collectionView setContentOffset:CGPointZero];
  }

pragma mark - functional methods

• (void)refreshPageIfNeeded { // 一小时进行刷新数据.
  NSTimeInterval currentStamp = [[NSDate date] timeIntervalSince1970];
  // 一小时内不做刷新 mark byKing
  if (self.infoList.count && currentStamp - _menuInfo.lastTime < 5) { //60 * 60
  return;
  }

  /*

  1. 第一次 _menuInfo.lastTime = 0, currentStamp 很大 肯定能刷新数据
  2. 第二次 _menuInfo.lastTime = currentStamp 必须等一个小时才能刷新数据

  */

  // 模拟网络请求延时，根据_menuInfo.menuId请求对应菜单项的相关信息
  dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.02 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
  _menuInfo.lastTime = currentStamp;
  [self handleNetworkSuccess];
  });
  }

• (void)cancelNetworkRequest {
  // 由于页面可能会被重用，需要取消不必要的网络请求
  // NSLog(@"maybe you should cancel network request in here");
  }

• (void)handleNetworkSuccess {
  NSLog(@"==模拟网络请求成功后刷新页面==");
  for (NSInteger index = 0; index < 50; index++) {
  [self.infoList addObject:[NSString stringWithFormat:@"image_%d", arc4random_uniform(13)]];
  }
  [self.collectionView reloadData];

}

• (void)savePageInfo {
  [[DataManager sharedInstance] savePageInfo:_infoList menuId:_menuInfo.menuId];
  }

// MARK: 设置menuInfo的时候加载本地数据

• (void)loadLocalData {
  NSArray *cacheList = [[DataManager sharedInstance] pageInfoWithMenuId:_menuInfo.menuId];
  [_infoList addObjectsFromArray:cacheList];
  [self.collectionView reloadData];
  }

pragma mark - accessor methods

• (void)setMenuInfo:(MenuInfo *)menuInfo {
  _menuInfo = menuInfo;
  // 复用VC步骤分析: >>> 3. 设置菜单信息的时候加载本地数据.
  [self loadLocalData];
  }

• (NSMutableArray *)infoList {
  if (!_infoList) {
  _infoList = [[NSMutableArray alloc] init];
  }
  return _infoList;
  }

@end

'''