TTTAttributedLabel.m

// TTTAttributedLabel.m
//
// Copyright (c) 2011 Mattt Thompson (http://mattt.me)
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

#import "TTTAttributedLabel.h"

#define kTTTLineBreakWordWrapTextWidthScalingFactor (M_PI / M_E)

NSString * const kTTTStrikeOutAttributeName = @"TTTStrikeOutAttribute";

static inline CTTextAlignment CTTextAlignmentFromUITextAlignment(UITextAlignment alignment) {
	switch (alignment) {
		case UITextAlignmentLeft: return kCTLeftTextAlignment;
		case UITextAlignmentCenter: return kCTCenterTextAlignment;
		case UITextAlignmentRight: return kCTRightTextAlignment;
		default: return kCTNaturalTextAlignment;
	}
}

static inline CTLineBreakMode CTLineBreakModeFromUILineBreakMode(UILineBreakMode lineBreakMode) {
	switch (lineBreakMode) {
		case UILineBreakModeWordWrap: return kCTLineBreakByWordWrapping;
		case UILineBreakModeCharacterWrap: return kCTLineBreakByCharWrapping;
		case UILineBreakModeClip: return kCTLineBreakByClipping;
		case UILineBreakModeHeadTruncation: return kCTLineBreakByTruncatingHead;
		case UILineBreakModeTailTruncation: return kCTLineBreakByTruncatingTail;
		case UILineBreakModeMiddleTruncation: return kCTLineBreakByTruncatingMiddle;
		default: return 0;
	}
}

static inline NSTextCheckingType NSTextCheckingTypeFromUIDataDetectorType(UIDataDetectorTypes dataDetectorType) {
    NSTextCheckingType textCheckingType = 0;
    if (dataDetectorType & UIDataDetectorTypeAddress) {
        textCheckingType |= NSTextCheckingTypeAddress;
    }
    
    if (dataDetectorType & UIDataDetectorTypeCalendarEvent) {
        textCheckingType |= NSTextCheckingTypeDate;
    }
    
    if (dataDetectorType & UIDataDetectorTypeLink) {
        textCheckingType |= NSTextCheckingTypeLink;
    }
    
    if (dataDetectorType & UIDataDetectorTypePhoneNumber) {
        textCheckingType |= NSTextCheckingTypePhoneNumber;
    }
    
    return textCheckingType;
}

static inline NSDictionary * NSAttributedStringAttributesFromLabel(TTTAttributedLabel *label) {
    NSMutableDictionary *mutableAttributes = [NSMutableDictionary dictionary]; 
    
    CTFontRef font = CTFontCreateWithName((CFStringRef)label.font.fontName, label.font.pointSize, NULL);
    [mutableAttributes setObject:(id)font forKey:(NSString *)kCTFontAttributeName];
    CFRelease(font);
    
    [mutableAttributes setObject:(id)[label.textColor CGColor] forKey:(NSString *)kCTForegroundColorAttributeName];
    
    CTTextAlignment alignment = CTTextAlignmentFromUITextAlignment(label.textAlignment);
    CGFloat lineSpacing = label.leading;
    CGFloat lineHeightMultiple = label.lineHeightMultiple;
    CGFloat topMargin = label.textInsets.top;
    CGFloat bottomMargin = label.textInsets.bottom;
    CGFloat leftMargin = label.textInsets.left;
    CGFloat rightMargin = label.textInsets.right;
    CGFloat firstLineIndent = label.firstLineIndent + leftMargin;

    CTLineBreakMode lineBreakMode;
    if (label.numberOfLines != 1) {
        lineBreakMode = CTLineBreakModeFromUILineBreakMode(UILineBreakModeWordWrap);
    }
    else {
        lineBreakMode = CTLineBreakModeFromUILineBreakMode(label.lineBreakMode);
    }
	
    CTParagraphStyleSetting paragraphStyles[9] = {
		{.spec = kCTParagraphStyleSpecifierAlignment, .valueSize = sizeof(CTTextAlignment), .value = (const void *)&alignment},
		{.spec = kCTParagraphStyleSpecifierLineBreakMode, .valueSize = sizeof(CTLineBreakMode), .value = (const void *)&lineBreakMode},
        {.spec = kCTParagraphStyleSpecifierLineSpacing, .valueSize = sizeof(CGFloat), .value = (const void *)&lineSpacing},
        {.spec = kCTParagraphStyleSpecifierLineHeightMultiple, .valueSize = sizeof(CGFloat), .value = (const void *)&lineHeightMultiple},
        {.spec = kCTParagraphStyleSpecifierFirstLineHeadIndent, .valueSize = sizeof(CGFloat), .value = (const void *)&firstLineIndent},
        {.spec = kCTParagraphStyleSpecifierParagraphSpacingBefore, .valueSize = sizeof(CGFloat), .value = (const void *)&topMargin},
        {.spec = kCTParagraphStyleSpecifierParagraphSpacing, .valueSize = sizeof(CGFloat), .value = (const void *)&bottomMargin},
        {.spec = kCTParagraphStyleSpecifierHeadIndent, .valueSize = sizeof(CGFloat), .value = (const void *)&leftMargin},
        {.spec = kCTParagraphStyleSpecifierTailIndent, .valueSize = sizeof(CGFloat), .value = (const void *)&rightMargin}
	};

    CTParagraphStyleRef paragraphStyle = CTParagraphStyleCreate(paragraphStyles, 9);
	[mutableAttributes setObject:(id)paragraphStyle forKey:(NSString *)kCTParagraphStyleAttributeName];
	CFRelease(paragraphStyle);
    
    return [NSDictionary dictionaryWithDictionary:mutableAttributes];
}

static inline NSAttributedString * NSAttributedStringByScalingFontSize(NSAttributedString *attributedString, CGFloat scale, CGFloat minimumFontSize) {    
    NSMutableAttributedString *mutableAttributedString = [[attributedString mutableCopy] autorelease];
    [mutableAttributedString enumerateAttribute:(NSString *)kCTFontAttributeName inRange:NSMakeRange(0, [mutableAttributedString length]) options:0 usingBlock:^(id value, NSRange range, BOOL *stop) {
        CTFontRef font = (CTFontRef)value;
        if (font) {
            CGFloat scaledFontSize = floorf(CTFontGetSize(font) * scale);
            CTFontRef scaledFont = CTFontCreateCopyWithAttributes(font, fmaxf(scaledFontSize, minimumFontSize), NULL, NULL);
            CFAttributedStringSetAttribute((CFMutableAttributedStringRef)mutableAttributedString, CFRangeMake(range.location, range.length), kCTFontAttributeName, scaledFont);
            CFRelease(scaledFont);
        }
    }];
    
    return mutableAttributedString;
}

@interface TTTAttributedLabel ()
@property (readwrite, nonatomic, copy) NSAttributedString *attributedText;
@property (readwrite, nonatomic, assign) CTFramesetterRef framesetter;
@property (readwrite, nonatomic, assign) CTFramesetterRef highlightFramesetter;
@property (readwrite, nonatomic, retain) NSDataDetector *dataDetector;
@property (readwrite, nonatomic, retain) NSArray *links;
@property (readwrite, nonatomic, retain) UITapGestureRecognizer *tapGestureRecognizer;

- (void)commonInit;
- (void)setNeedsFramesetter;
- (NSArray *)detectedLinksInString:(NSString *)string range:(NSRange)range error:(NSError **)error;
- (NSTextCheckingResult *)linkAtCharacterIndex:(CFIndex)idx;
- (NSTextCheckingResult *)linkAtPoint:(CGPoint)p;
- (CFIndex)characterIndexAtPoint:(CGPoint)p;
- (void)drawFramesetter:(CTFramesetterRef)framesetter textRange:(CFRange)textRange inRect:(CGRect)rect context:(CGContextRef)c;
- (void)drawStrike:(CTFrameRef)frame inRect:(CGRect)rect context:(CGContextRef)c;
- (void)handleTap:(UITapGestureRecognizer *)gestureRecognizer;
@end

@implementation TTTAttributedLabel
@dynamic text;
@synthesize attributedText = _attributedText;
@synthesize framesetter = _framesetter;
@synthesize highlightFramesetter = _highlightFramesetter;
@synthesize delegate = _delegate;
@synthesize dataDetectorTypes = _dataDetectorTypes;
@synthesize dataDetector = _dataDetector;
@synthesize links = _links;
@synthesize linkAttributes = _linkAttributes;
@synthesize shadowRadius = _shadowRadius;
@synthesize leading = _leading;
@synthesize lineHeightMultiple = _lineHeightMultiple;
@synthesize firstLineIndent = _firstLineIndent;
@synthesize textInsets = _textInsets;
@synthesize verticalAlignment = _verticalAlignment;
@synthesize tapGestureRecognizer = _tapGestureRecognizer;

- (id)initWithFrame:(CGRect)frame {
    self = [super initWithFrame:frame];
    if (!self) {
        return nil;
    }
    
    [self commonInit];
    
    return self;
}

- (id)initWithCoder:(NSCoder *)coder {
    self = [super initWithCoder:coder];
    if (!self) {
        return nil;
    }
    
    [self commonInit];
    
    return self;
}

- (void)commonInit {
    self.dataDetectorTypes = UIDataDetectorTypeNone;
    self.links = [NSArray array];
    
    NSMutableDictionary *mutableLinkAttributes = [NSMutableDictionary dictionary];
    [mutableLinkAttributes setValue:(id)[[UIColor blueColor] CGColor] forKey:(NSString*)kCTForegroundColorAttributeName];
    [mutableLinkAttributes setValue:[NSNumber numberWithBool:YES] forKey:(NSString *)kCTUnderlineStyleAttributeName];
    self.linkAttributes = [NSDictionary dictionaryWithDictionary:mutableLinkAttributes];
    
    self.textInsets = UIEdgeInsetsZero;
    
    self.userInteractionEnabled = YES;
    self.tapGestureRecognizer = [[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleTap:)] autorelease];
    [self.tapGestureRecognizer setDelegate:self];
    [self addGestureRecognizer:self.tapGestureRecognizer];
}

- (void)dealloc {
    if (_framesetter) CFRelease(_framesetter);
    if (_highlightFramesetter) CFRelease(_highlightFramesetter);
    
    [_attributedText release];
    [_dataDetector release];
    [_links release];
    [_linkAttributes release];
    [_tapGestureRecognizer release];
    [super dealloc];
}

#pragma mark -

- (void)setAttributedText:(NSAttributedString *)text {
    if ([text isEqualToAttributedString:self.attributedText]) {
        return;
    }
    
    [self willChangeValueForKey:@"attributedText"];
    [_attributedText release];
    _attributedText = [text copy];
    [self didChangeValueForKey:@"attributedText"];
    
    [self setNeedsFramesetter];
}

- (void)setNeedsFramesetter {
    _needsFramesetter = YES;
}

- (CTFramesetterRef)framesetter {
    if (_needsFramesetter) {
        @synchronized(self) {
            if (_framesetter) CFRelease(_framesetter);
            if (_highlightFramesetter) CFRelease(_highlightFramesetter);
            
            self.framesetter = CTFramesetterCreateWithAttributedString((CFAttributedStringRef)self.attributedText);
            self.highlightFramesetter = nil;
            _needsFramesetter = NO;
        }
    }
    
    return _framesetter;
}

#pragma mark -

- (void)setDataDetectorTypes:(UIDataDetectorTypes)dataDetectorTypes {
    [self willChangeValueForKey:@"dataDetectorTypes"];
    _dataDetectorTypes = dataDetectorTypes;
    [self didChangeValueForKey:@"dataDetectorTypes"];
    
    if (self.dataDetectorTypes != UIDataDetectorTypeNone) {
        self.dataDetector = [NSDataDetector dataDetectorWithTypes:NSTextCheckingTypeFromUIDataDetectorType(self.dataDetectorTypes) error:nil];
    }
}

- (NSArray *)detectedLinksInString:(NSString *)string range:(NSRange)range error:(NSError **)error {
    if (!string || !self.dataDetector) {
        return [NSArray array];
    }
    
    NSMutableArray *mutableLinks = [NSMutableArray array];
    [self.dataDetector enumerateMatchesInString:string options:0 range:range usingBlock:^(NSTextCheckingResult *result, NSMatchingFlags flags, BOOL *stop) {
        [mutableLinks addObject:result];
    }];
    
    return [NSArray arrayWithArray:mutableLinks];
}

- (void)addLinkWithTextCheckingResult:(NSTextCheckingResult *)result attributes:(NSDictionary *)attributes {
    self.links = [self.links arrayByAddingObject:result];
    
    if (attributes) {
        NSMutableAttributedString *mutableAttributedString = [[[NSMutableAttributedString alloc] initWithAttributedString:self.attributedText] autorelease];
        [mutableAttributedString addAttributes:attributes range:result.range];
        self.attributedText = mutableAttributedString;        
    }
}

- (void)addLinkWithTextCheckingResult:(NSTextCheckingResult *)result {
    [self addLinkWithTextCheckingResult:result attributes:self.linkAttributes];
}

- (void)addLinkToURL:(NSURL *)url withRange:(NSRange)range {
    [self addLinkWithTextCheckingResult:[NSTextCheckingResult linkCheckingResultWithRange:range URL:url]];
}

- (void)addLinkToAddress:(NSDictionary *)addressComponents withRange:(NSRange)range {
    [self addLinkWithTextCheckingResult:[NSTextCheckingResult addressCheckingResultWithRange:range components:addressComponents]];
}

- (void)addLinkToPhoneNumber:(NSString *)phoneNumber withRange:(NSRange)range {
    [self addLinkWithTextCheckingResult:[NSTextCheckingResult phoneNumberCheckingResultWithRange:range phoneNumber:phoneNumber]];
}

- (void)addLinkToDate:(NSDate *)date withRange:(NSRange)range {
    [self addLinkWithTextCheckingResult:[NSTextCheckingResult dateCheckingResultWithRange:range date:date]];
}

- (void)addLinkToDate:(NSDate *)date timeZone:(NSTimeZone *)timeZone duration:(NSTimeInterval)duration withRange:(NSRange)range {
    [self addLinkWithTextCheckingResult:[NSTextCheckingResult dateCheckingResultWithRange:range date:date timeZone:timeZone duration:duration]];
}

#pragma mark -

- (NSTextCheckingResult *)linkAtCharacterIndex:(CFIndex)idx {
    for (NSTextCheckingResult *result in self.links) {
        NSRange range = result.range;
        if ((CFIndex)range.location <= idx && idx <= (CFIndex)(range.location + range.length - 1)) {
            return result;
        }
    }
    
    return nil;
}

- (NSTextCheckingResult *)linkAtPoint:(CGPoint)p {
    CFIndex idx = [self characterIndexAtPoint:p];
    return [self linkAtCharacterIndex:idx];
}

- (CFIndex)characterIndexAtPoint:(CGPoint)p {
    if (!CGRectContainsPoint(self.bounds, p)) {
        return NSNotFound;
    }
    
    CGRect textRect = [self textRectForBounds:self.bounds limitedToNumberOfLines:self.numberOfLines];
    if (!CGRectContainsPoint(textRect, p)) {
        return NSNotFound;
    }
    
    // Offset tap coordinates by textRect origin to make them relative to the origin of frame
    p = CGPointMake(p.x - textRect.origin.x, p.y - textRect.origin.y);
    // Convert tap coordinates (start at top left) to CT coordinates (start at bottom left)
    p = CGPointMake(p.x, textRect.size.height - p.y);

    CGMutablePathRef path = CGPathCreateMutable();
    CGPathAddRect(path, NULL, textRect);
    CTFrameRef frame = CTFramesetterCreateFrame(self.framesetter, CFRangeMake(0, [self.attributedText length]), path, NULL);
    if (frame == NULL) {
        CFRelease(path);
        return NSNotFound;
    }

    CFArrayRef lines = CTFrameGetLines(frame);
    NSUInteger numberOfLines = self.numberOfLines > 0 ? MIN(self.numberOfLines, CFArrayGetCount(lines)) : CFArrayGetCount(lines);
    if (numberOfLines == 0) {
        CFRelease(frame);
        CFRelease(path);
        return NSNotFound;
    }
    
    NSUInteger idx = NSNotFound;

    CGPoint lineOrigins[numberOfLines];
    CTFrameGetLineOrigins(frame, CFRangeMake(0, 0), lineOrigins);

    for (CFIndex lineIndex = 0; lineIndex < (numberOfLines - 1); lineIndex++) {
        CGPoint lineOrigin = lineOrigins[lineIndex];
        CTLineRef line = CFArrayGetValueAtIndex(lines, lineIndex);
        
        // Get bounding information of line
        CGFloat ascent, descent, leading, width;
        width = CTLineGetTypographicBounds(line, &ascent, &descent, &leading);
        CGFloat yMin = floor(lineOrigin.y - descent);
        CGFloat yMax = ceil(lineOrigin.y + ascent);
        
        // Check if we've already passed the line
        if (p.y > yMax) {
            break;
        }
        // Check if the point is within this line vertically
        if (p.y >= yMin) {
            // Check if the point is within this line horizontally
            if (p.x >= lineOrigin.x && p.x <= lineOrigin.x + width) {
                // Convert CT coordinates to line-relative coordinates
                CGPoint relativePoint = CGPointMake(p.x - lineOrigin.x, p.y - lineOrigin.y);
                idx = CTLineGetStringIndexForPosition(line, relativePoint);
                break;
            }
        }
    }
    
    CFRelease(frame);
    CFRelease(path);
        
    return idx;
}

- (void)drawFramesetter:(CTFramesetterRef)framesetter textRange:(CFRange)textRange inRect:(CGRect)rect context:(CGContextRef)c {
    CGMutablePathRef path = CGPathCreateMutable();
    
    CGPathAddRect(path, NULL, rect);
    CTFrameRef frame = CTFramesetterCreateFrame(framesetter, textRange, path, NULL);    
    
    CFArrayRef lines = CTFrameGetLines(frame);
    NSUInteger numberOfLines = self.numberOfLines > 0 ? MIN(self.numberOfLines, CFArrayGetCount(lines)) : CFArrayGetCount(lines);
    BOOL truncateLastLine = (self.lineBreakMode == UILineBreakModeHeadTruncation || self.lineBreakMode == UILineBreakModeMiddleTruncation || self.lineBreakMode == UILineBreakModeTailTruncation);
    
    CGPoint lineOrigins[numberOfLines];
    CTFrameGetLineOrigins(frame, CFRangeMake(0, numberOfLines), lineOrigins);
    
    for (CFIndex lineIndex = 0; lineIndex < numberOfLines; lineIndex++) {
        CGPoint lineOrigin = lineOrigins[lineIndex];
        CGContextSetTextPosition(c, lineOrigin.x, lineOrigin.y);
        CTLineRef line = CFArrayGetValueAtIndex(lines, lineIndex);
        
        if (lineIndex == numberOfLines - 1 && truncateLastLine) {
            // Check if the range of text in the last line reaches the end of the full attributed string
            CFRange lastLineRange = CTLineGetStringRange(line);
            
            if (lastLineRange.location + lastLineRange.length < textRange.location + textRange.length) {
                // Get correct truncationType and attribute position
                CTLineTruncationType truncationType;
                NSUInteger truncationAttributePosition = lastLineRange.location;
                UILineBreakMode lineBreakMode = self.lineBreakMode;
                
                // Multiple lines, only use UILineBreakModeTailTruncation
                if (numberOfLines != 1) {
                    lineBreakMode = UILineBreakModeTailTruncation;
                }
                
                switch (lineBreakMode) {
                    case UILineBreakModeHeadTruncation:
                        truncationType = kCTLineTruncationStart;
                        break;
                    case UILineBreakModeMiddleTruncation:
                        truncationType = kCTLineTruncationMiddle;
                        truncationAttributePosition += (lastLineRange.length / 2);
                        break;
                    case UILineBreakModeTailTruncation:
                    default:
                        truncationType = kCTLineTruncationEnd;
                        truncationAttributePosition += (lastLineRange.length - 1);
                        break;
                }
                
                // Get the attributes and use them to create the truncation token string
                NSDictionary *tokenAttributes = [self.attributedText attributesAtIndex:truncationAttributePosition effectiveRange:NULL];
                // \u2026 is the Unicode horizontal ellipsis character code
                NSAttributedString *tokenString = [[[NSAttributedString alloc] initWithString:@"\u2026" attributes:tokenAttributes] autorelease];
                CTLineRef truncationToken = CTLineCreateWithAttributedString((CFAttributedStringRef)tokenString);
                
                // Append truncationToken to the string
                // because if string isn't too long, CT wont add the truncationToken on it's own
                // There is no change of a double truncationToken because CT only add the token if it removes characters (and the one we add will go first)
                NSMutableAttributedString *truncationString = [[[self.attributedText attributedSubstringFromRange:NSMakeRange(lastLineRange.location, lastLineRange.length)] mutableCopy] autorelease];
                if (lastLineRange.length > 0) {
                    // Remove any newline at the end (we don't want newline space between the text and the truncation token). There can only be one, because the second would be on the next line.
                    unichar lastCharacter = [[truncationString string] characterAtIndex:lastLineRange.length - 1];
                    if ([[NSCharacterSet newlineCharacterSet] characterIsMember:lastCharacter]) {
                        [truncationString deleteCharactersInRange:NSMakeRange(lastLineRange.length - 1, 1)];
                    }
                }
                [truncationString appendAttributedString:tokenString];
                CTLineRef truncationLine = CTLineCreateWithAttributedString((CFAttributedStringRef)truncationString);

                // Truncate the line in case it is too long.
                CTLineRef truncatedLine = CTLineCreateTruncatedLine(truncationLine, rect.size.width, truncationType, truncationToken);
                if (!truncatedLine) {
                    // If the line is not as wide as the truncationToken, truncatedLine is NULL
                    truncatedLine = CFRetain(truncationToken);
                }
                
                CTLineDraw(truncatedLine, c);
                
                CFRelease(truncatedLine);
                CFRelease(truncationLine);
                CFRelease(truncationToken);
            } else {
                CTLineDraw(line, c);
            }
        } else {
            CTLineDraw(line, c);
        }
    }

    [self drawStrike:frame inRect:rect context:c];
    
    CFRelease(frame);
    CFRelease(path);
}

- (void)drawStrike:(CTFrameRef)frame inRect:(CGRect)rect context:(CGContextRef)c {
    NSArray *lines = (NSArray *)CTFrameGetLines(frame);
    CGPoint origins[[lines count]];
    CTFrameGetLineOrigins(frame, CFRangeMake(0, 0), origins);
    
    CFIndex lineIndex = 0;
    for (id line in lines) {        
        CGRect lineBounds = CTLineGetImageBounds((CTLineRef)line, c);
        lineBounds.origin.x = origins[lineIndex].x;
        lineBounds.origin.y = origins[lineIndex].y;
        
        for (id glyphRun in (NSArray *)CTLineGetGlyphRuns((CTLineRef)line)) {
            NSDictionary *attributes = (NSDictionary *)CTRunGetAttributes((CTRunRef) glyphRun);
            BOOL strikeOut = [[attributes objectForKey:kTTTStrikeOutAttributeName] boolValue];
            NSInteger superscriptStyle = [[attributes objectForKey:(id)kCTSuperscriptAttributeName] integerValue];
            
            if (strikeOut) {
                CGRect runBounds = CGRectZero;
                CGFloat ascent = 0.0f;
                CGFloat descent = 0.0f;
                
                runBounds.size.width = CTRunGetTypographicBounds((CTRunRef)glyphRun, CFRangeMake(0, 0), &ascent, &descent, NULL);
                runBounds.size.height = ascent + descent;
                
                CGFloat xOffset = CTLineGetOffsetForStringIndex((CTLineRef)line, CTRunGetStringRange((CTRunRef)glyphRun).location, NULL);
                runBounds.origin.x = origins[lineIndex].x + rect.origin.x + xOffset;
                runBounds.origin.y = origins[lineIndex].y + rect.origin.y;
                runBounds.origin.y -= descent;
                
                // Don't draw strikeout too far to the right
                if (CGRectGetWidth(runBounds) > CGRectGetWidth(lineBounds)) {
                    runBounds.size.width = CGRectGetWidth(lineBounds);
                }
                
				switch (superscriptStyle) {
					case 1:
						runBounds.origin.y -= ascent * 0.47f;
						break;
					case -1:
						runBounds.origin.y += ascent * 0.25f;
						break;
					default:
						break;
				}
                
                // Use text color, or default to black
                id color = [attributes objectForKey:(id)kCTForegroundColorAttributeName];

                if (color) {
                    CGContextSetStrokeColorWithColor(c, (CGColorRef)color);
                } else {
                    CGContextSetGrayStrokeColor(c, 0.0f, 1.0);
                }
                
                CTFontRef font = CTFontCreateWithName((CFStringRef)self.font.fontName, self.font.pointSize, NULL);
                CGContextSetLineWidth(c, CTFontGetUnderlineThickness(font));
                CGFloat y = roundf(runBounds.origin.y + runBounds.size.height / 2.0f);
                CGContextMoveToPoint(c, runBounds.origin.x, y);
                CGContextAddLineToPoint(c, runBounds.origin.x + runBounds.size.width, y);
                
                CGContextStrokePath(c);
            }
        }
        
        lineIndex++;
    }
}

#pragma mark - TTTAttributedLabel

- (void)setText:(id)text {
    if ([text isKindOfClass:[NSString class]]) {
        [self setText:text afterInheritingLabelAttributesAndConfiguringWithBlock:nil];
        return;
    }
    
    self.attributedText = text;

    self.links = [NSArray array];
    if (self.dataDetectorTypes != UIDataDetectorTypeNone) {
        for (NSTextCheckingResult *result in [self detectedLinksInString:[self.attributedText string] range:NSMakeRange(0, [text length]) error:nil]) {
            [self addLinkWithTextCheckingResult:result];
        }
    }
        
    [super setText:[self.attributedText string]];
}

- (void)setText:(id)text afterInheritingLabelAttributesAndConfiguringWithBlock:(NSMutableAttributedString *(^)(NSMutableAttributedString *mutableAttributedString))block {    
    NSMutableAttributedString *mutableAttributedString = nil;
    if ([text isKindOfClass:[NSString class]]) {
        mutableAttributedString = [[[NSMutableAttributedString alloc] initWithString:text attributes:NSAttributedStringAttributesFromLabel(self)] autorelease];
    } else {
        mutableAttributedString = [[[NSMutableAttributedString alloc] initWithAttributedString:text] autorelease];
        [mutableAttributedString addAttributes:NSAttributedStringAttributesFromLabel(self) range:NSMakeRange(0, [mutableAttributedString length])];
    }
    
    if (block) {
        mutableAttributedString = block(mutableAttributedString);
    }
    
    [self setText:mutableAttributedString];
}

#pragma mark - UILabel

- (void)setHighlighted:(BOOL)highlighted {
    [super setHighlighted:highlighted];
    [self setNeedsDisplay];
}

- (CGRect)textRectForBounds:(CGRect)bounds limitedToNumberOfLines:(NSInteger)numberOfLines {
    if (!self.attributedText) {
        return [super textRectForBounds:bounds limitedToNumberOfLines:numberOfLines];
    }
    
    // *Note: we aren't taking numberOfLines into consideration here
    
    CGRect textRect = bounds;
    
    // Adjust the text to be in the center vertically, if the text size is smaller than bounds
    CGSize textSize = CTFramesetterSuggestFrameSizeWithConstraints(self.framesetter, CFRangeMake(0, [self.attributedText length]), NULL, bounds.size, NULL);
    textSize = CGSizeMake(ceilf(textSize.width), ceilf(textSize.height)); // Fix for iOS 4, CTFramesetterSuggestFrameSizeWithConstraints sometimes returns fractional sizes
    
    if (textSize.height < textRect.size.height) {
        CGFloat yOffset = 0.0f;
        switch (self.verticalAlignment) {
            case TTTAttributedLabelVerticalAlignmentTop:
                break;
            case TTTAttributedLabelVerticalAlignmentCenter:
                yOffset = floorf((textRect.size.height - textSize.height) / 2.0f);
                break;
            case TTTAttributedLabelVerticalAlignmentBottom:
                yOffset = textRect.size.height - textSize.height;
                break;
        }
        
        textRect.origin.y += yOffset;
        textRect.size.height = textSize.height;
    }
    
    return textRect;
}

- (void)drawTextInRect:(CGRect)rect {
    if (!self.attributedText) {
        [super drawTextInRect:rect];
        return;
    }
    
    NSAttributedString *originalAttributedText = nil;
    // Adjust the font size to fit width, if necessarry 
    if (self.adjustsFontSizeToFitWidth && self.numberOfLines > 0) {
        CGFloat textWidth = [self sizeThatFits:CGSizeZero].width;
        CGFloat availableWidth = self.frame.size.width * self.numberOfLines;
        if (self.numberOfLines > 1 && self.lineBreakMode == UILineBreakModeWordWrap) {
            textWidth *= kTTTLineBreakWordWrapTextWidthScalingFactor;
        }
        
        if (textWidth > availableWidth && textWidth > 0.0f) {
            originalAttributedText = [[self.attributedText copy] autorelease];
            self.text = NSAttributedStringByScalingFontSize(self.attributedText, availableWidth / textWidth, self.minimumFontSize);
        }
    }
    
    CGContextRef c = UIGraphicsGetCurrentContext();
    CGContextSetTextMatrix(c, CGAffineTransformIdentity);

    // Inverts the CTM to match iOS coordinates (otherwise text draws upside-down; Mac OS's system is different)
    CGContextTranslateCTM(c, 0.0f, rect.size.height);
    CGContextScaleCTM(c, 1.0f, -1.0f);
    
    CFRange textRange = CFRangeMake(0, [self.attributedText length]);

    // First, get the text rect (which takes vertical centering into account)
    CGRect textRect = [self textRectForBounds:rect limitedToNumberOfLines:self.numberOfLines];

    // CoreText draws it's text aligned to the bottom, so we move the CTM here to take our vertical offsets into account
    CGContextTranslateCTM(c, 0.0f, rect.size.height - textRect.origin.y - textRect.size.height);

    // Second, trace the shadow before the actual text, if we have one
    if (self.shadowColor && !self.highlighted) {
        CGContextSetShadowWithColor(c, self.shadowOffset, self.shadowRadius, [self.shadowColor CGColor]);
    }
    
    // Finally, draw the text or highlighted text itself (on top of the shadow, if there is one)
    if (self.highlightedTextColor && self.highlighted) {
        if (!self.highlightFramesetter) {
            NSMutableAttributedString *mutableAttributedString = [[self.attributedText mutableCopy] autorelease];
            [mutableAttributedString addAttribute:(NSString *)kCTForegroundColorAttributeName value:(id)[self.highlightedTextColor CGColor] range:NSMakeRange(0, mutableAttributedString.length)];
            self.highlightFramesetter = CTFramesetterCreateWithAttributedString((CFAttributedStringRef)mutableAttributedString);
        }
        
        [self drawFramesetter:self.highlightFramesetter textRange:textRange inRect:textRect context:c];
    } else {
        [self drawFramesetter:self.framesetter textRange:textRange inRect:textRect context:c];
    }  
    
    // If we adjusted the font size, set it back to its original size
    if (originalAttributedText) {
        self.text = originalAttributedText;
    }
}

#pragma mark - UIView

- (CGSize)sizeThatFits:(CGSize)size {
    if (!self.attributedText) {
        return [super sizeThatFits:size];
    }
    
    CFRange rangeToSize = CFRangeMake(0, [self.attributedText length]);
    CGSize constraints = CGSizeMake(size.width, CGFLOAT_MAX);
    
    if (self.numberOfLines == 1) {
        // If there is one line, the size that fits is the full width of the line
        constraints = CGSizeMake(CGFLOAT_MAX, CGFLOAT_MAX);
    } else if (self.numberOfLines > 0) {
        // If the line count of the label more than 1, limit the range to size to the number of lines that have been set
        CGMutablePathRef path = CGPathCreateMutable();
        CGPathAddRect(path, NULL, CGRectMake(0.0f, 0.0f, constraints.width, CGFLOAT_MAX));
        CTFrameRef frame = CTFramesetterCreateFrame(self.framesetter, CFRangeMake(0, 0), path, NULL);
        CFArrayRef lines = CTFrameGetLines(frame);
        
        if (CFArrayGetCount(lines) > 0) {
            NSInteger lastVisibleLineIndex = MIN(self.numberOfLines, CFArrayGetCount(lines)) - 1;
            CTLineRef lastVisibleLine = CFArrayGetValueAtIndex(lines, lastVisibleLineIndex);
            
            CFRange rangeToLayout = CTLineGetStringRange(lastVisibleLine);
            rangeToSize = CFRangeMake(0, rangeToLayout.location + rangeToLayout.length);
        }
        
        CFRelease(frame);
        CFRelease(path);
    }
    
    CGSize suggestedSize = CTFramesetterSuggestFrameSizeWithConstraints(self.framesetter, rangeToSize, NULL, constraints, NULL);
    
    return CGSizeMake(ceilf(suggestedSize.width), ceilf(suggestedSize.height));
}

#pragma mark - UIGestureRecognizer

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch {
    return [self linkAtPoint:[touch locationInView:self]] != nil;
}

- (void)handleTap:(UITapGestureRecognizer *)gestureRecognizer {
    if ([gestureRecognizer state] != UIGestureRecognizerStateEnded) {
        return;
    }
    
    NSTextCheckingResult *result = [self linkAtPoint:[gestureRecognizer locationInView:self]];
    if (!result || !self.delegate) {
        return;
    }
    
    switch (result.resultType) {
        case NSTextCheckingTypeLink:
            if ([self.delegate respondsToSelector:@selector(attributedLabel:didSelectLinkWithURL:)]) {
                [self.delegate attributedLabel:self didSelectLinkWithURL:result.URL];
                return;
            }
            break;
        case NSTextCheckingTypeAddress:
            if ([self.delegate respondsToSelector:@selector(attributedLabel:didSelectLinkWithAddress:)]) {
                [self.delegate attributedLabel:self didSelectLinkWithAddress:result.addressComponents];
                return;
            }
            break;
        case NSTextCheckingTypePhoneNumber:
            if ([self.delegate respondsToSelector:@selector(attributedLabel:didSelectLinkWithPhoneNumber:)]) {
                [self.delegate attributedLabel:self didSelectLinkWithPhoneNumber:result.phoneNumber];
                return;
            }
            break;
        case NSTextCheckingTypeDate:
            if (result.timeZone && [self.delegate respondsToSelector:@selector(attributedLabel:didSelectLinkWithDate:timeZone:duration:)]) {
                [self.delegate attributedLabel:self didSelectLinkWithDate:result.date timeZone:result.timeZone duration:result.duration];
                return;
            } else if ([self.delegate respondsToSelector:@selector(attributedLabel:didSelectLinkWithDate:)]) {
                [self.delegate attributedLabel:self didSelectLinkWithDate:result.date];
                return;
            }
            break;
    }
    
    // Fallback to `attributedLabel:didSelectLinkWithTextCheckingResult:` if no other delegate method matched.
    if ([self.delegate respondsToSelector:@selector(attributedLabel:didSelectLinkWithTextCheckingResult:)]) {
        [self.delegate attributedLabel:self didSelectLinkWithTextCheckingResult:result];
    }
}

@end