//
//  YH_BarrageTableView.m
//  YHBarrage
//
//  Created by Arthur on 16/6/6.
//  Copyright © 2016年 YOHO!. All rights reserved.
//

#import "YH_BarrageTableView.h"
#import "NSMutableArray+QueueAdditions.h"
#import "YH_BarrageMsgCell.h"
#import "YH_BarrageJoinCell.h"
#import "UtilsMacros.h"
#import <pthread.h>
#define kMessageCellID @"MessageCelliden"
#define kJoinCellID @"JoinCellIden"
#define MaxMessageCacheCapacity 20
#define kCacheProcessingTimerInterval 2

#define IsStrEmpty(_ref)            (IsNilOrNull(_ref) || (![(_ref) isKindOfClass:[NSString class]]) || ([(_ref) isEqualToString:@""]))

@interface YH_BarrageTableView (){
    NSTimer *_cacheProcessingTimer; // 定时将缓冲区数据加到dataMutableArray
    NSTimer *_scrollingTableViewTimer; // 定时刷新tableview
    dispatch_queue_t _syncQueue;
    NSMutableArray *_messageBuffer; // 缓冲消息
    
}

@property (strong, nonatomic) NSMutableArray *dataMutableArray;
@property (nonatomic) BOOL manualScrolling; //是否手动滑动列表
@property (nonatomic) BOOL isMutipleJoin; // 连续两条数据都是【用户加入】的消息
@property (nonatomic) NSUInteger newMsgCount; // 新消息数量
@property (strong, nonatomic) dispatch_queue_t messageProgressingQueue;
//@property (nonatomic) NSUInteger lastRow;     // 当手动滑动tableview时，记录最后一条cell的位置


@end

@implementation YH_BarrageTableView
{
    NSMutableArray *_dataMutableArray;
}


- (instancetype)init
{
    self = [super init];
    if (self) {
        self.delegate = self;
        self.dataSource = self;
        _syncQueue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
        _messageBuffer = [[NSMutableArray alloc]init];
        self.dataMutableArray = [[NSMutableArray alloc]init];
        
        // 缓冲区定时器
        if (_cacheProcessingTimer == nil) {
            _cacheProcessingTimer = [NSTimer timerWithTimeInterval:kCacheProcessingTimerInterval target:self selector:@selector(appendCacheToDataArray) userInfo:nil repeats:YES];
            [[NSRunLoop mainRunLoop] addTimer:_cacheProcessingTimer forMode:NSRunLoopCommonModes];
        }
    }
    
    [self setBackgroundColor:[UIColor clearColor]];
    [self setShowsVerticalScrollIndicator:NO];
    self.separatorStyle = UITableViewCellSeparatorStyleNone;
    
    return self;
}

-(id)hitTest:(CGPoint)point withEvent:(UIEvent *)event {
    id hitView = [super hitTest:point withEvent:event];
    if (hitView == self) return nil;
    else return hitView;
}

- (void)reset
{
    if (_cacheProcessingTimer) {
        [_cacheProcessingTimer invalidate];
        _cacheProcessingTimer = nil;
    }
    
    if (_scrollingTableViewTimer) {
        [_scrollingTableViewTimer invalidate];
        _scrollingTableViewTimer = nil;
    }
    
    [self resetDataMutableArray];
    [self reloadData];
}
- (void)resetDataMutableArray
{
    [self.dataMutableArray removeAllObjects];
}

- (void)yhBarrageTableView:(YH_BarrageTableView *)barrageTableView insertCellWithItem:(NSDictionary *)itemDic
{
    
    __weak typeof (self) weakSelf = self;
    
    if (itemDic && ![itemDic isEqual:[NSNull null]] && !IsStrEmpty([itemDic objectForKey:@"name"])) {
        if (0) {
//            [self greenChannel:itemDic];
        } else {
            
            if ([[itemDic objectForKey:@"cmd"] longValue] == 4/*user join*/ && !self.manualScrolling) {
                // 如果是用户加入的消息，则不加入到缓冲区
                [self newUserJoin:itemDic];
            } else {
                // 现将数据插入到cache
                dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
                    
                    YH_BarrageMsgModel *message = [[YH_BarrageMsgModel alloc]initWithDictionary:itemDic error:nil];
                    if (_messageBuffer) {
                        [_messageBuffer enqueue:message];
                    } else {
                        _messageBuffer = [NSMutableArray new];
                        [_messageBuffer enqueue:message];
                    }
                    
                    
                    dispatch_async(dispatch_get_main_queue(), ^{
                        if (weakSelf.manualScrolling) {
                            weakSelf.newMsgCount ++ ;
                            if ([weakSelf.barrageScrollingDelegate respondsToSelector:@selector(manualScrollingWithNewMsgCount:)]) {
                                [weakSelf.barrageScrollingDelegate manualScrollingWithNewMsgCount:[NSString stringWithFormat:@"%ld", weakSelf.newMsgCount]];
                            }
                        } else {
                            weakSelf.newMsgCount = 0;
                            if ([weakSelf.barrageScrollingDelegate respondsToSelector:@selector(autoScollingCallback)]) {
                                [weakSelf.barrageScrollingDelegate autoScollingCallback];
                                CGPoint bottomOffset = CGPointMake(0, weakSelf.contentSize.height - weakSelf.bounds.size.height);
                                [weakSelf setContentOffset:bottomOffset animated:YES];
                            }
                        }
                    });
                    
                });
                
            }
            
        }
        
    }
    
    
    
}

- (void)newUserJoin:(NSDictionary *)item {
    __weak typeof (self) weakSelf = self;
    if (pthread_main_np() != 0) {
        // main thread
        [weakSelf caculateContentInset];
        YH_BarrageMsgModel *newMessage = [[YH_BarrageMsgModel alloc]initWithDictionary:item error:nil];
        YH_BarrageMsgModel *oldMessage = [weakSelf.dataMutableArray lastObject];
        
        if ([weakSelf.dataMutableArray count] && oldMessage && oldMessage.cmd == newMessage.cmd && oldMessage.cmd == 4) {
            [weakSelf.dataMutableArray replaceObjectAtIndex:[weakSelf.dataMutableArray count]-1 withObject:newMessage];
        } else {
            [weakSelf.dataMutableArray addObject:newMessage];
        }
        
        [weakSelf reloadData];
        CGPoint bottomOffset = CGPointMake(0, weakSelf.contentSize.height - weakSelf.bounds.size.height);
        [weakSelf setContentOffset:bottomOffset animated:YES];
    }else {
        dispatch_sync(dispatch_get_main_queue(), ^{
            [weakSelf caculateContentInset];
            YH_BarrageMsgModel *newMessage = [[YH_BarrageMsgModel alloc]initWithDictionary:item error:nil];
            YH_BarrageMsgModel *oldMessage = [weakSelf.dataMutableArray lastObject];
            
            if ([weakSelf.dataMutableArray count] && oldMessage && oldMessage.cmd == newMessage.cmd && oldMessage.cmd == 4) {
                [weakSelf.dataMutableArray replaceObjectAtIndex:[weakSelf.dataMutableArray count]-1 withObject:newMessage];
            } else {
                [weakSelf.dataMutableArray addObject:newMessage];
            }
            
            [weakSelf reloadData];
            CGPoint bottomOffset = CGPointMake(0, weakSelf.contentSize.height - weakSelf.bounds.size.height);
            [weakSelf setContentOffset:bottomOffset animated:YES];
        });
    }
    
}
// 将缓冲区中的数据存入tableview的数据源
- (void)appendCacheToDataArray {
    
    __weak typeof (self) weakSelf = self;
    __strong typeof (weakSelf) strongSelf = weakSelf;
    
    if ([_messageBuffer count]) {
        dispatch_async(dispatch_get_main_queue(), ^{
            
            [weakSelf.dataMutableArray addObjectsFromArray:strongSelf->_messageBuffer];
            
            // 启动刷新列表的timer
            if (_scrollingTableViewTimer == nil && !weakSelf.manualScrolling && [strongSelf->_messageBuffer count]) {
                _scrollingTableViewTimer = [NSTimer timerWithTimeInterval:1 target:weakSelf selector:@selector(scrollingTableViewToBottom) userInfo:nil repeats:YES];
                [[NSRunLoop mainRunLoop] addTimer:_scrollingTableViewTimer forMode:NSRunLoopCommonModes];
                
            }
            
            [strongSelf->_messageBuffer removeAllObjects];
            
        });
    }
  
}

// 如果返回的数据是本机用户所发，则立即显示，不需要走缓冲策略，直接加入到tableview数据源，刷新列表
- (void)greenChannel:(NSDictionary *)item {
    __weak typeof (self) weakSelf = self;
    if (pthread_main_np() != 0) {
        // main thread
        [weakSelf caculateContentInset];
        YH_BarrageMsgModel *message = [[YH_BarrageMsgModel alloc]initWithDictionary:item error:nil];
        [weakSelf.dataMutableArray addObject:message];
        [weakSelf reloadData];
        CGPoint bottomOffset = CGPointMake(0, weakSelf.contentSize.height - weakSelf.bounds.size.height);
        [weakSelf setContentOffset:bottomOffset animated:YES];
    }else {
        dispatch_sync(dispatch_get_main_queue(), ^{
            [weakSelf caculateContentInset];
            YH_BarrageMsgModel *message = [[YH_BarrageMsgModel alloc]initWithDictionary:item error:nil];
            [weakSelf.dataMutableArray addObject:message];
            [weakSelf reloadData];
            CGPoint bottomOffset = CGPointMake(0, weakSelf.contentSize.height - weakSelf.bounds.size.height);
            [weakSelf setContentOffset:bottomOffset animated:YES];
        });
    }
    
}


- (void)scrollingTableViewToBottom {
    __weak typeof (self) weakSelf = self;
    dispatch_async(dispatch_get_main_queue(), ^{
        
        [weakSelf caculateContentInset];
        
        // 做内存保护，数组内数据大于上限时强制清掉
        if (weakSelf.dataMutableArray.count >= MaxQueueCapacity) {
            [weakSelf.dataMutableArray removeAllObjects];
        }
        
        [weakSelf reloadData];

        CGPoint bottomOffset = CGPointMake(0, weakSelf.contentSize.height - weakSelf.bounds.size.height);
        [weakSelf setContentOffset:bottomOffset animated:YES];

        if (_scrollingTableViewTimer) {
            [_scrollingTableViewTimer invalidate];
            _scrollingTableViewTimer = nil;
        }
        
    });
}


// 自动更新tableview
- (void)startAutoScolling
{
    self.manualScrolling = NO;
    self.newMsgCount = 0;
    [self appendCacheToDataArray];
    
    CGPoint bottomOffset = CGPointMake(0, self.contentSize.height - self.bounds.size.height);
    [self setContentOffset:bottomOffset animated:YES];
    
    if ([self.barrageScrollingDelegate respondsToSelector:@selector(autoScollingCallback)]) {
        [self.barrageScrollingDelegate autoScollingCallback];
    }
    
    
    if (_scrollingTableViewTimer == nil) {
        _scrollingTableViewTimer = [NSTimer timerWithTimeInterval:1 target:self selector:@selector(scrollingTableViewToBottom) userInfo:nil repeats:YES];
        [[NSRunLoop mainRunLoop] addTimer:_scrollingTableViewTimer forMode:NSRunLoopCommonModes];
    }
}


// 判断tableview是否滑到底部
- (BOOL)isLastTableViewCell {
    return (self.contentOffset.y >= (self.contentSize.height - self.frame.size.height));
}

// 通过设置contentInset 实现cell从下至上‘生长’动画
- (void)caculateContentInset
{
    CGSize contentSize = self.contentSize;
    CGFloat tableViewHeight = CGRectGetHeight(self.frame);
    
    if (contentSize.height <=  tableViewHeight) {
        
        CGFloat contentHeight = contentSize.height;
        [self setContentInset:UIEdgeInsetsMake(tableViewHeight-contentHeight, 0, 0, 0)];
    } else {
        [self setContentInset:UIEdgeInsetsMake(0, 0, 0, 0)];
    }
    
}

- (void)compare:(NSDictionary *)newItem {
    NSDictionary *oldItem = [self.dataMutableArray lastObject];
    long oldItemCmd = [[oldItem objectForKey:@"cmd"] longValue];
    long newItemCmd = [[newItem objectForKey:@"cmd"] longValue];
    
    if (oldItem && oldItemCmd == newItemCmd && oldItemCmd == 4) {
        self.isMutipleJoin = YES;
    } else {
        self.isMutipleJoin = NO;
    }
}


#pragma mark - User respond

#pragma mark - UIScrollViewDelegate
- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView
{
    self.manualScrolling = YES;
    if (_scrollingTableViewTimer) {
        [_scrollingTableViewTimer invalidate];
        _scrollingTableViewTimer = nil;
    }
  
}

- (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate
{
    NSLog(@"%s", __func__);
    
    if ([self isLastTableViewCell]) {
        [self startAutoScolling];
    }
    
}


- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView
{
    if ([self isLastTableViewCell]) {
        [self startAutoScolling];
    }
}

#pragma mark - UITableViewDataSource

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    return [self.dataMutableArray count];
}

- (NSInteger)numberOfRowsInSection:(NSInteger)section
{
    return 1;
}

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    //    return 44.0f;
    
    YH_BarrageMsgModel *message  = [self.dataMutableArray objectAtIndex:indexPath.row];
    
    if (message) {
      
        if (message.cmd == 5) {
            return [YH_BarrageMsgCell cellHeightWithMessage:message];
        } else {
            return 26;
        }
    }
    
    return 44;

}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    
    YH_BarrageMsgModel *message  = [self.dataMutableArray objectAtIndex:indexPath.row];
    
    
    if (message.cmd == 5) { // 聊天消息
        YH_BarrageMsgCell *cell = [self dequeueReusableCellWithIdentifier:kMessageCellID];
        if (cell == nil) {
            cell = [[YH_BarrageMsgCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:kMessageCellID];
        }

        [cell updateCellWithMessage:message cellWidth:CGRectGetWidth(tableView.frame)];
        
        return cell;
        
    } else if(message.cmd == 4) {
        // 用户加入
        YH_BarrageJoinCell *cell = [self dequeueReusableCellWithIdentifier:kJoinCellID];
        if (cell == nil) {
            cell = [[YH_BarrageJoinCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:kJoinCellID];
        }
        cell.msgModel = message;
        
        return cell;
    }
    
    return nil;

}


#pragma mark - UITableViewDelegate

#pragma mark - getters and setters

// 读操作同步
- (NSMutableArray *)dataMutableArray
{
    __block __weak  NSMutableArray *localDataMutableArray;
    dispatch_sync(_syncQueue, ^{
        localDataMutableArray = _dataMutableArray;
    });
    
    return localDataMutableArray;
}

// 写操作异步（且读操作完成后进行）
-(void)setDataMutableArray:(NSMutableArray *)dataMutableArray
{
    dispatch_barrier_async(_syncQueue, ^{
        _dataMutableArray = dataMutableArray;
    });
}


@end