NSAttributedStringをちょっとは使いやすくするやーつ

ANZTextStyle.h

#import <Foundation/Foundation.h>

@interface ANZTextStyle : NSObject

@property (nonatomic, readonly) ANZTextStyle *(^text)(NSString *text);
@property (nonatomic, readonly) ANZTextStyle *(^lineHeight)(CGFloat height);
@property (nonatomic, readonly) ANZTextStyle *(^breakMode)(NSLineBreakMode mode);
@property (nonatomic, readonly) ANZTextStyle *(^align)(NSTextAlignment align);
@property (nonatomic, readonly) ANZTextStyle *(^color)(UIColor *color);
@property (nonatomic, readonly) ANZTextStyle *(^font)(UIFont *font);
@property (nonatomic, readonly) ANZTextStyle *(^bgColor)(UIColor *color);
@property (nonatomic, readonly) ANZTextStyle *(^baseline)(CGFloat offset);
@property (nonatomic, readonly) ANZTextStyle *(^underline)();
@property (nonatomic, readonly) ANZTextStyle *(^kern)(CGFloat value);
@property (nonatomic, readonly) ANZTextStyle *(^range)(NSInteger offset, NSInteger length);

- (instancetype)initWithString:(NSString *)string;
- (NSAttributedString *)build;
- (void)clean;

@end

@interface NSString (ANZ_TextStyleExtension)
- (ANZTextStyle *)style;
@end

ANZTextStyle.m

#import "ANZTextStyle.h"

static NSString * const kParagraphKeyLineHeight = @"height";
static NSString * const kParagraphKeyAlignment = @"alignment";
static NSString * const kParagraphKeyBreakMode = @"breakmode";

@interface ANZTextStyle()
@property (nonatomic) NSMutableDictionary *attributes;
@property (nonatomic) NSMutableDictionary *paragraph;
@property (nonatomic) NSString *string;
@property (nonatomic) NSRange applyRange;
@end

@implementation ANZTextStyle

- (instancetype)initWithString:(NSString *)string {
    if (self = [super init]) {
        _string = string;
        _attributes = [NSMutableDictionary new];
        _paragraph = [NSMutableDictionary new];
    }
    return self;
}

#pragma mark - getter
- (ANZTextStyle *(^)(NSString *))text {
    return ^ANZTextStyle *(NSString *text) {
        self.string = text;
        return self;
    };
}

- (ANZTextStyle *(^)(CGFloat))lineHeight {
    return ^ANZTextStyle *(CGFloat height) {
        self.paragraph[kParagraphKeyLineHeight] = @(height);
        return self;
    };
}

- (ANZTextStyle *(^)(NSLineBreakMode))breakMode {
    return ^ANZTextStyle *(NSLineBreakMode mode) {
        self.paragraph[kParagraphKeyBreakMode] = @(mode);
        return self;
    };
}

- (ANZTextStyle *(^)(NSTextAlignment))align {
    return ^ANZTextStyle *(NSTextAlignment align) {
        self.paragraph[kParagraphKeyAlignment] = @(align);
        return self;
    };
}

- (ANZTextStyle *(^)(UIColor *))color {
    return ^ANZTextStyle *(UIColor *color) {
        self.attributes[NSForegroundColorAttributeName] = color;
        return self;
    };
}

- (ANZTextStyle *(^)(UIFont *))font {
    return ^ANZTextStyle *(UIFont *font) {
        self.attributes[NSFontAttributeName] = font;
        return self;
    };
}

- (ANZTextStyle *(^)(UIColor *))bgColor {
    return ^ANZTextStyle *(UIColor *bgColor) {
        self.attributes[NSBackgroundColorAttributeName] = bgColor;
        return self;
    };
}

- (ANZTextStyle *(^)(CGFloat))baseline {
    return ^ANZTextStyle *(CGFloat baseline) {
        self.attributes[NSBaselineOffsetAttributeName] = @(baseline);
        return self;
    };
}

- (ANZTextStyle *(^)())underline {
    return ^ANZTextStyle *() {
        self.attributes[NSUnderlineStyleAttributeName] = @(NSUnderlineStyleSingle);
        return self;
    };
}

- (ANZTextStyle *(^)(CGFloat))kern {
    return ^ANZTextStyle *(CGFloat value) {
        self.attributes[NSKernAttributeName] = @(value);
        return self;
    };
}

- (ANZTextStyle *(^)(NSInteger offset, NSInteger length))range {
    return ^ANZTextStyle *(NSInteger offset, NSInteger length) {
        self.applyRange = NSMakeRange(offset, length);
        return self;
    };
}

#pragma mark - setter
- (void)setString:(NSString *)string {
  _string = string;
  self.applyRange = NSMakeRange(0, 0); // string変わったらrangeはクリアする
}

#pragma mark - method
- (NSAttributedString *)build {
    
    NSAssert(self.string.length, @"string is empty!!!!");
    
    NSParagraphStyle *paragraphStyle = [self makeParagraph];
    if (paragraphStyle) {
        self.attributes[NSParagraphStyleAttributeName] = paragraphStyle;
    }
    
    if (self.applyRange.length) {
        NSMutableAttributedString *attributeString = [[NSMutableAttributedString alloc] initWithString:self.string];
        [attributeString addAttributes:self.attributes range:self.applyRange];
        return [[NSAttributedString alloc] initWithAttributedString: attributeString];
    } else {
        return [[NSAttributedString alloc] initWithString:self.string attributes:self.attributes];
    }
    
}

- (void)clean {
    self.attributes = [NSMutableDictionary new];
    self.paragraph = [NSMutableDictionary new];
    self.applyRange = NSMakeRange(0, 0);
}

- (NSParagraphStyle *)makeParagraph {
    
    if (![self.paragraph allKeys].count) {
        return nil;
    }
    
    NSMutableParagraphStyle *style = [[NSMutableParagraphStyle alloc] init];
    NSNumber *value = self.paragraph[kParagraphKeyLineHeight];
    if (value) {
        style.maximumLineHeight = style.minimumLineHeight = value.floatValue;
    }
    value = self.paragraph[kParagraphKeyAlignment];
    if (value) {
        style.alignment = (NSTextAlignment)value.integerValue;
    }
    value = self.paragraph[kParagraphKeyBreakMode];
    if (value) {
        style.lineBreakMode = (NSLineBreakMode)value.integerValue;
    }
    
    return style;
}

@end

@implementation NSString(ANZ_TextStyleExtension)

- (ANZTextStyle *)style {
    return [[ANZTextStyle alloc] initWithString:self];
}

@end