//
//  YMSwitch.m
//  YUMI
//
//  Created by YUMI on 2023/2/9.
//

#import "XPSwitch.h"
#import <QuartzCore/QuartzCore.h>

static const CGFloat kAnimateDuration = 0.3f;
static const CGFloat kHorizontalAdjustment = 3.0f;
static const CGFloat kRectShapeCornerRadius = 4.0f;
static const CGFloat kThumbShadowOpacity = 0.3f;
static const CGFloat kThumbShadowRadius = 0.5f;
static const CGFloat kSwitchBorderWidth = 1.75f;

@interface XPSwitch ()

@property (nonatomic, strong) UIView *onBackgroundView;
@property (nonatomic, strong) UIView *offBackgroundView;
@property (nonatomic, strong) UIView *thumbView;

@end
@implementation XPSwitch

@synthesize onBackgroundView = _onBackgroundView;
@synthesize offBackgroundView = _offBackgroundView;
@synthesize thumbView = _thumbView;
@synthesize on = _on;
@synthesize shape = _shape;
@synthesize onTintColor = _onTintColor;
@synthesize tintColor = _tintColor;
@synthesize thumbTintColor = _thumbTintColor;
@synthesize shadow = _shadow;
@synthesize onTintBorderColor = _onTintBorderColor;
@synthesize tintBorderColor = _tintBorderColor;

#pragma mark - View
- (id)initWithFrame:(CGRect)frame {
	self = [super initWithFrame:frame];
	if (self) {
		[self setupUI];
	}
	return self;
}

- (void) awakeFromNib {
	[super awakeFromNib];

	[self setupUI];
}

- (void)setupUI {
	self.shape = CHSwitchShapeOval;

	[self setBackgroundColor:[UIColor clearColor]];

	// Background view for ON
	self.onBackgroundView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, self.frame.size.width, self.frame.size.height)];
	[self.onBackgroundView setBackgroundColor:[UIColor colorWithRed:(19.0f/255.0f) green:(121.0f/255.0f) blue:(208.0f/255.0f) alpha:1.0f]];
	[self.onBackgroundView.layer setCornerRadius:self.frame.size.height/2];
	[self.onBackgroundView.layer setShouldRasterize:YES];
	[self.onBackgroundView.layer setRasterizationScale:[UIScreen mainScreen].scale];
	[self addSubview:self.onBackgroundView];

	// Background view for OFF
	self.offBackgroundView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, self.frame.size.width, self.frame.size.height)];
	[self.offBackgroundView setBackgroundColor:[UIColor whiteColor]];
	[self.offBackgroundView.layer setCornerRadius:self.frame.size.height/2];
	[self.offBackgroundView.layer setShouldRasterize:YES];
	[self.offBackgroundView.layer setRasterizationScale:[UIScreen mainScreen].scale];
	[self addSubview:self.offBackgroundView];

	// Round switch view
	self.thumbView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, self.frame.size.height-kHorizontalAdjustment, self.frame.size.height-kHorizontalAdjustment)];
	[self.thumbView setBackgroundColor:[UIColor whiteColor]];
	[self.thumbView setUserInteractionEnabled:YES];
	[self.thumbView.layer setCornerRadius:(self.frame.size.height-kHorizontalAdjustment)/2];
	[self.thumbView.layer setShadowOffset:CGSizeMake(0, 1)];
	[self.thumbView.layer setShouldRasterize:YES];
	[self.thumbView.layer setShadowOpacity:kThumbShadowOpacity];
	[self.thumbView.layer setRasterizationScale:[UIScreen mainScreen].scale];
	[self addSubview:self.thumbView];
	self.shadow = YES;

	// Default to OFF position
	[self.thumbView setCenter:CGPointMake(self.thumbView.frame.size.width/2, self.frame.size.height/2)];

	// Handle Thumb Tap Gesture
	UITapGestureRecognizer *tapGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self
																						   action:@selector(handleSwitchTap:)];
	[tapGestureRecognizer setDelegate:self];
	[self.thumbView addGestureRecognizer:tapGestureRecognizer];

	// Handle Background Tap Gesture
	UITapGestureRecognizer *tapBgGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleBgTap:)];
	[tapBgGestureRecognizer setDelegate:self];
	[self addGestureRecognizer:tapBgGestureRecognizer];

	// Handle Thumb Pan Gesture
	UIPanGestureRecognizer *panGestureRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(handlePan:)];
	[panGestureRecognizer setDelegate:self];
	[self.thumbView addGestureRecognizer:panGestureRecognizer];

	[self setOn:NO];
}

#pragma mark - Accessor
- (BOOL)isOn {
	return _on;
}

- (void)setOn:(BOOL)on {
	if (_on != on)
		_on = on;

	if (_on) {
		[self.onBackgroundView setAlpha:1.0];
		self.offBackgroundView.transform = CGAffineTransformMakeScale(0.0, 0.0);

		self.thumbView.center = CGPointMake(self.onBackgroundView.frame.size.width - (self.thumbView.frame.size.width + kHorizontalAdjustment)/2, self.thumbView.center.y);
	}
	else {
		[self.onBackgroundView setAlpha:0.0];
		self.offBackgroundView.transform = CGAffineTransformMakeScale(1.0, 1.0);

		self.thumbView.center = CGPointMake((self.thumbView.frame.size.width+kHorizontalAdjustment)/2, self.thumbView.center.y);
	}
}

- (void)setOnTintColor:(UIColor *)color
{
	if (_onTintColor != color)
		_onTintColor = color;

	[self.onBackgroundView setBackgroundColor:color];
}

- (void)setOnTintBorderColor:(UIColor *)color
{
	if (_onTintBorderColor != color)
		_onTintBorderColor = color;

	[self.onBackgroundView.layer setBorderColor:color.CGColor];

	if (color)
		[self.onBackgroundView.layer setBorderWidth:kSwitchBorderWidth];
	else
		[self.onBackgroundView.layer setBorderWidth:0.0];
}

- (void)setTintColor:(UIColor *)color
{
	if (_tintColor != color)
		_tintColor = color;

	[self.offBackgroundView setBackgroundColor:color];
}

- (void)setTintBorderColor:(UIColor *)color
{
	if (_tintBorderColor != color)
		_tintBorderColor = color;

	[self.offBackgroundView.layer setBorderColor:color.CGColor];

	if (color)
		[self.offBackgroundView.layer setBorderWidth:kSwitchBorderWidth];
	else
		[self.offBackgroundView.layer setBorderWidth:0.0];
}

- (void)setThumbTintColor:(UIColor *)color
{
	if (_thumbTintColor != color)
		_thumbTintColor = color;

	[self.thumbView setBackgroundColor:color];
}

- (void)setShape:(CHSwitchShape)newShape
{
	if (_shape != newShape)
		_shape = newShape;

	if (newShape == CHSwitchShapeOval)
	{
		[self.onBackgroundView.layer setCornerRadius:self.frame.size.height/2];
		[self.offBackgroundView.layer setCornerRadius:self.frame.size.height/2];
		[self.thumbView.layer setCornerRadius:(self.frame.size.height-kHorizontalAdjustment)/2];
	}
	else if (newShape == CHSwitchShapeRectangle)
	{
		[self.onBackgroundView.layer setCornerRadius:kRectShapeCornerRadius];
		[self.offBackgroundView.layer setCornerRadius:kRectShapeCornerRadius];
		[self.thumbView.layer setCornerRadius:kRectShapeCornerRadius];
	}
	else if (newShape == CHSwitchShapeRectangleNoCorner)
	{
		[self.onBackgroundView.layer setCornerRadius:0];
		[self.offBackgroundView.layer setCornerRadius:0];
		[self.thumbView.layer setCornerRadius:0];
	}
}

- (void)setShadow:(BOOL)showShadow
{
	if (_shadow != showShadow)
		_shadow = showShadow;

	if (showShadow)
	{
		[self.thumbView.layer setShadowOffset:CGSizeMake(0, 1)];
		[self.thumbView.layer setShadowRadius:kThumbShadowRadius];
		[self.thumbView.layer setShadowOpacity:kThumbShadowOpacity];
	}
	else
	{
		[self.thumbView.layer setShadowRadius:0.0];
		[self.thumbView.layer setShadowOpacity:0.0];
	}
}

#pragma mark - Animation
- (void)animateToDestination:(CGPoint)centerPoint withDuration:(CGFloat)duration switch:(BOOL)on
{
	[UIView animateWithDuration:duration
						  delay:0.0f
						options:UIViewAnimationOptionCurveEaseOut
					 animations:^{
		self.thumbView.center = centerPoint;

		if (on)
		{
			[self.onBackgroundView setAlpha:1.0];
		}
		else
		{
			[self.onBackgroundView setAlpha:0.0];
		}

	}
					 completion:^(BOOL finished) {
		if (finished)
		{
			[self updateSwitch:on];
		}

	}];

	[UIView animateWithDuration:duration
						  delay:0.075f
						options:UIViewAnimationOptionCurveEaseOut
					 animations:^{
		if (on)
		{
			self.offBackgroundView.transform = CGAffineTransformMakeScale(0.0, 0.0);
		}
		else
		{
			self.offBackgroundView.transform = CGAffineTransformMakeScale(1.0, 1.0);
		}

	}
					 completion:^(BOOL finished) {
	}];
}



#pragma mark - Gesture Recognizers
- (void)handlePan:(UIPanGestureRecognizer *)recognizer
{
	CGPoint translation = [recognizer translationInView:self.thumbView];

	// Check the new center to see if within the boud
	CGPoint newCenter = CGPointMake(recognizer.view.center.x + translation.x,
									recognizer.view.center.y);
	if (newCenter.x < (recognizer.view.frame.size.width+kHorizontalAdjustment)/2 || newCenter.x > self.onBackgroundView.frame.size.width-(recognizer.view.frame.size.width+kHorizontalAdjustment)/2)
	{
		// New center is Out of bound. Animate to left or right position
		if(recognizer.state == UIGestureRecognizerStateBegan ||
		   recognizer.state == UIGestureRecognizerStateChanged)
		{
			CGPoint velocity = [recognizer velocityInView:self.thumbView];

			if (velocity.x >= 0)
			{
				// Animate move to right
				[self animateToDestination:CGPointMake(self.onBackgroundView.frame.size.width - (self.thumbView.frame.size.width+kHorizontalAdjustment)/2, recognizer.view.center.y) withDuration:kAnimateDuration switch:YES];
			}
			else
			{
				// Animate move to left
				[self animateToDestination:CGPointMake((self.thumbView.frame.size.width+kHorizontalAdjustment)/2, recognizer.view.center.y) withDuration:kAnimateDuration switch:NO];
			}

		}

		return;
	}

	// Only allow vertical pan
	recognizer.view.center = CGPointMake(recognizer.view.center.x + translation.x,
										 recognizer.view.center.y);
	[recognizer setTranslation:CGPointMake(0, 0) inView:self.thumbView];

	CGPoint velocity = [recognizer velocityInView:self.thumbView];

	if(recognizer.state == UIGestureRecognizerStateEnded)
	{
		if (velocity.x >= 0)
		{
			if (recognizer.view.center.x < self.onBackgroundView.frame.size.width - (self.thumbView.frame.size.width+kHorizontalAdjustment)/2)
			{
				// Animate move to right
				[self animateToDestination:CGPointMake(self.onBackgroundView.frame.size.width - (self.thumbView.frame.size.width+kHorizontalAdjustment)/2, recognizer.view.center.y) withDuration:kAnimateDuration switch:YES];
			}
		}
		else
		{
			// Animate move to left
			[self animateToDestination:CGPointMake((self.thumbView.frame.size.width+kHorizontalAdjustment)/2, recognizer.view.center.y) withDuration:kAnimateDuration switch:NO];
		}
	}
}

- (void)handleSwitchTap:(UIPanGestureRecognizer *)recognizer
{
	if (recognizer.state == UIGestureRecognizerStateEnded)
	{
		if (self.isOn)
		{
			// Animate move to left
			[self animateToDestination:CGPointMake((self.thumbView.frame.size.width+kHorizontalAdjustment)/2, recognizer.view.center.y) withDuration:kAnimateDuration switch:NO];
		}
		else
		{
			// Animate move to right
			[self animateToDestination:CGPointMake(self.onBackgroundView.frame.size.width - (self.thumbView.frame.size.width+kHorizontalAdjustment)/2, recognizer.view.center.y) withDuration:kAnimateDuration switch:YES];
		}
	}
}

- (void)handleBgTap:(UIPanGestureRecognizer *)recognizer
{
	if (recognizer.state == UIGestureRecognizerStateEnded)
	{
		if (self.isOn)
		{
			// Animate move to left
			[self animateToDestination:CGPointMake((self.thumbView.frame.size.width+kHorizontalAdjustment)/2, self.thumbView.center.y) withDuration:kAnimateDuration switch:NO];
		}
		else
		{
			// Animate move to right
			[self animateToDestination:CGPointMake(self.onBackgroundView.frame.size.width - (self.thumbView.frame.size.width+kHorizontalAdjustment)/2, self.thumbView.center.y) withDuration:kAnimateDuration switch:YES];
		}
	}
}

#pragma mark -
- (void)updateSwitch:(BOOL)on
{
	if (_on != on)
		_on = on;

	[self sendActionsForControlEvents:UIControlEventValueChanged];
}

@end