//
//  TPViewController.m
//  ThePaperDemo
//
//  Created by Scar on 14-9-2.
//  Copyright (c) 2014年 scar1900. All rights reserved.
//

#import "TPViewController.h"

#define deltaHeight 40

@interface TPViewController () <UIGestureRecognizerDelegate> {
    CGFloat oriLabelHeight;
    CGFloat edgeY;
}

@property (nonatomic, weak)	UIView* scrollableView;
@property (assign, nonatomic) float lastContentOffset;
@property (strong, nonatomic) UIPanGestureRecognizer* panGesture;
@property (assign, nonatomic) BOOL isCollapsed;
@property (assign, nonatomic) BOOL isExpanded;

@end

@implementation TPViewController
@synthesize naviBar;
@synthesize barHeight;
@synthesize lineView;

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        // Custom initialization
    }
    return self;
}

- (CGFloat)barHeight {
    return self.naviBar.frame.size.height;
}

- (void)followScrollView:(UIView*)scrollableView
{
	self.scrollableView = scrollableView;
	
	self.panGesture = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(handlePan:)];
	[self.panGesture setMaximumNumberOfTouches:1];
	
	[self.panGesture setDelegate:self];
	[self.scrollableView addGestureRecognizer:self.panGesture];
    
    self.panGesture.enabled = NO;

	CGRect frame = self.naviBar.frame;
	frame.origin = CGPointZero;
	self.overlay = [[UIView alloc] initWithFrame:frame];
	if (!self.naviBar.backgroundColor) {
		TPLOG(@"[%s]: %@", __func__, @"Warning: no back color set");
	}
	[self.overlay setBackgroundColor:self.naviBar.backgroundColor];
	[self.overlay setUserInteractionEnabled:NO];
	[self.naviBar addSubview:self.overlay];
	[self.overlay setAlpha:0];
    
    [self.naviBar bringSubviewToFront:self.lineView];
}

- (void)disableFollowScroll {
    self.panGesture.enabled = NO;
}

- (void)enableFollowScroll {
//    self.panGesture.enabled = YES;
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    self.view.backgroundColor = [UIColor colorWithHexString:BackGroundColor];
    // Do any additional setup after loading the view.
    
    [self.navigationController.navigationBar setHidden:YES];
    [self setNavigationbar];
    
    lineView = [[UIView alloc]initWithFrame:CGRectZero];
    lineView.backgroundColor = [UIColor colorWithHexString:LINECOLOR];
    [self.naviBar addSubview:lineView];
    
    [self.lineView makeConstraints:^(MASConstraintMaker *make) {
        make.left.equalTo(self.naviBar.left);
        make.right.equalTo(self.naviBar.right);
        make.bottom.equalTo(self.naviBar.bottom);
        make.height.equalTo(@0.5);
    }];
    
    UITapGestureRecognizer *tapGesture = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(tapNaviBar:)];
    [self.naviBar addGestureRecognizer:tapGesture];
}


- (void)setNavigationbar
{
    CGRect screenRect = [[UIScreen mainScreen] bounds];
    self.naviBar = [[UIView alloc]init];
    self.naviBar.backgroundColor  = [UIColor colorWithHexString:BackGroundColor];
    if (isIOS7) {
        self.naviBar.frame = CGRectMake(0, 0, screenRect.size.width, 156/2);
        oriLabelHeight = 25;
        edgeY = 16;
    }else {
        self.naviBar.frame = CGRectMake(0, 0, screenRect.size.width, 120/2);
        oriLabelHeight = 25-16;
        edgeY = 0;
    }
    [self.view addSubview:self.naviBar];
}

- (void)addBarChildView {
    
}

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
	return YES;
}

- (void)handlePan:(UIPanGestureRecognizer*)gesture
{
	CGPoint translation = [gesture translationInView:[self.scrollableView superview]];
	
	float delta = self.lastContentOffset - translation.y;
	self.lastContentOffset = translation.y;
    
    UILabel *label = (UILabel*)[self.view viewWithTag:kXHLabelBaseTag+self.currentIndex];

    CGRect labelFrame;
	
	CGRect frame;
    
	
	if (delta > 0) {
		if (self.isCollapsed) {
			return;
		}
		
		frame = self.naviBar.frame;
        labelFrame = label.frame;
		
		if (frame.origin.y - delta < 0-deltaHeight) {
			delta = frame.origin.y + deltaHeight;
		}
        
		frame.origin.y = MAX(0-deltaHeight, frame.origin.y - delta);
        labelFrame.origin.y = MAX(oriLabelHeight-deltaHeight, labelFrame.origin.y - delta);
        self.naviBar.frame = frame;
        if (labelFrame.origin.y <= edgeY) {
            labelFrame.origin.y = edgeY;
        }
        label.frame = labelFrame;
        
//        labelFrame = label.frame;
//        if (frame.origin.y <= -10) {
//            
//        }
//		
		if (frame.origin.y == 0-deltaHeight) {
			self.isCollapsed = YES;
			self.isExpanded = NO;
		}
		
		[self updateSizingWithDelta:delta];
		
		// Keeps the view's scroll position steady until the navbar is gone
		if ([self.scrollableView isKindOfClass:[UIScrollView class]]) {
			[(UIScrollView*)self.scrollableView setContentOffset:CGPointMake(((UIScrollView*)self.scrollableView).contentOffset.x, ((UIScrollView*)self.scrollableView).contentOffset.y - delta)];
		}
	}
	
	if (delta < 0) {
		if (self.isExpanded) {
			return;
		}
		
		frame = self.naviBar.frame;
        labelFrame = label.frame;
		
		if (frame.origin.y - delta > 0) {
			delta = frame.origin.y - 0;
		}
		frame.origin.y = MIN(0, frame.origin.y - delta);
        labelFrame.origin.y = MIN(oriLabelHeight, labelFrame.origin.y - delta);
		self.naviBar.frame = frame;
        if (labelFrame.origin.y <= edgeY) {
            labelFrame.origin.y = edgeY;
        }
        label.frame = labelFrame;
		
		if (frame.origin.y == 0) {
			self.isExpanded = YES;
			self.isCollapsed = NO;
		}
		
		[self updateSizingWithDelta:delta];
	}
	
	if ([gesture state] == UIGestureRecognizerStateEnded) {
		// Reset the nav bar if the scroll is partial
		self.lastContentOffset = 0;
		[self checkForPartialScroll];
	}
}

- (void)checkForPartialScroll
{
	CGFloat pos = self.naviBar.frame.origin.y;
    UILabel *label = (UILabel*)[self.view viewWithTag:kXHLabelBaseTag+self.currentIndex];
	// Get back down
	if (pos >= -2) {
		[UIView animateWithDuration:0.2 animations:^{
			CGRect frame;
            CGRect labelFrame;
			frame = self.naviBar.frame;
            labelFrame = label.frame;
			CGFloat delta = frame.origin.y - 0;
			frame.origin.y = MIN(0, frame.origin.y - delta);
            labelFrame.origin.y = MIN(oriLabelHeight, labelFrame.origin.y - delta);
			self.naviBar.frame = frame;
            if (labelFrame.origin.y <= edgeY) {
                labelFrame.origin.y = edgeY;
            }
            label.frame = labelFrame;
			
			self.isExpanded = YES;
			self.isCollapsed = NO;
            
			[self updateSizingWithDelta:delta];
			
//			// This line needs tweaking
//			// [self.scrollView setContentOffset:CGPointMake(self.scrollView.contentOffset.x, self.scrollView.contentOffset.y - delta) animated:YES];
		}];
	} else {
		// And back up
		[UIView animateWithDuration:0.2 animations:^{
			CGRect frame;
            CGRect labelFrame;
			frame = self.naviBar.frame;
            labelFrame = label.frame;
			CGFloat delta = frame.origin.y + deltaHeight;
			frame.origin.y = MAX(0-deltaHeight, frame.origin.y - delta);
            labelFrame.origin.y = MAX(oriLabelHeight-deltaHeight, labelFrame.origin.y - delta);
			self.naviBar.frame = frame;
            if (labelFrame.origin.y <= edgeY) {
                labelFrame.origin.y = edgeY;
            }
            label.frame = labelFrame;
			
			self.isExpanded = NO;
			self.isCollapsed = YES;
			
			[self updateSizingWithDelta:delta];
		}];
	}
}

- (void)updateSizingWithDelta:(CGFloat)delta
{
    if (delta >= 0.5) {
        delta = 0.5;
    }
	CGRect frame = self.naviBar.frame;
	
	float alpha = 2*(frame.origin.y + deltaHeight) / frame.size.height;
    
    CGFloat textFontScale = TEXT_ONE_LEVELSIZE - TEXT_FOUR_LEVELSIZE;
    CGFloat textFont = textFontScale * alpha + TEXT_FOUR_LEVELSIZE;
    UILabel *label = (UILabel*)[self.view viewWithTag:kXHLabelBaseTag+self.currentIndex];

	[self.overlay setAlpha:(1 - alpha)*2];
    if (self.overlay.alpha >= 1) {
        self.overlay.userInteractionEnabled = YES;
    }else {
        self.overlay.userInteractionEnabled = NO;
    }
    /**
     * bug:5055(首页，在收缩顶部菜单时，点击右上角，依然有效，之后收起后有异常)
     */
    label.font = appFont(textFont, NO);
    
	frame = self.scrollableView.frame;
	frame.origin.y = self.naviBar.frame.origin.y + self.naviBar.frame.size.height;
//	frame.size.height = frame.size.height + delta;
    self.scrollableView.frame = frame;

	// Changing the layer's frame avoids UIWebView's glitchiness
	frame = self.scrollableView.layer.frame;
	frame.size.height += delta;
	self.scrollableView.layer.frame = frame;
}

- (void)resetNaviBar {
    /**
     * bug:5027&&5217(瀑布流 ：上推以后，导航栏澎湃文字会离时间很近)
     */

    [UIView animateWithDuration:0.25 animations:^{
        if (isIOS7) {
            self.naviBar.frame = CGRectMake(0, 0, rect_screen.size.width, 156/2);
        }else {
            self.naviBar.frame = CGRectMake(0, 0, rect_screen.size.width, 120/2);
        }
        [self updateSizingWithDelta:0.5];
        
        UILabel *label = (UILabel*)[self.view viewWithTag:kXHLabelBaseTag+self.currentIndex];
        CGRect rect = label.frame;
        rect.origin.y = 25;
        label.frame = rect;
    }completion:^(BOOL finished) {
        self.isCollapsed = NO;
    }];
}


- (void)tapNaviBar:(id)sender {
    
}

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


@end