PSStyleSheet.m

//
//  PSStyleSheet.m
//  PSKit
//
//  Created by Peter Shih on 8/10/11.
//  Copyright (c) 2011 Peter Shih.. All rights reserved.
//

#import "PSStyleSheet.h"

static PSStyleSheet *__defaultStyleSheet = nil;

@interface UIColor (PSStyleSheet)

+ (UIColor *)colorWithRGBHex:(UInt32)hex;
+ (UIColor *)colorWithHexString:(NSString *)stringToConvert;

@end

@implementation UIColor (PSStyleSheet)

+ (UIColor *)colorWithRGBHex:(UInt32)hex {
    int r = (hex >> 16) & 0xFF;
    int g = (hex >> 8) & 0xFF;
    int b = (hex) & 0xFF;
    
    return [UIColor colorWithRed:r / 255.0f
                           green:g / 255.0f
                            blue:b / 255.0f
                           alpha:1.0f];
}

// Returns a UIColor by scanning the string for a hex number and passing that to +[UIColor colorWithRGBHex:]
// Skips any leading whitespace and ignores any trailing characters
+ (UIColor *)colorWithHexString:(NSString *)stringToConvert {
    NSScanner *scanner = [NSScanner scannerWithString:stringToConvert];
    unsigned hexNum;
    if (![scanner scanHexInt:&hexNum]) return nil;
    return [UIColor colorWithRGBHex:hexNum];
}

@end

@interface UILabel (PSStyleSheet_Private)

+ (CGSize)sizeForText:(NSString*)text width:(CGFloat)width font:(UIFont*)font numberOfLines:(NSInteger)numberOfLines lineBreakMode:(UILineBreakMode)lineBreakMode;
@end

@implementation UILabel (PSStyleSheet_Private)

+ (CGSize)sizeForText:(NSString*)text width:(CGFloat)width font:(UIFont*)font numberOfLines:(NSInteger)numberOfLines lineBreakMode:(UILineBreakMode)lineBreakMode {
    
    if (numberOfLines == 0) numberOfLines = INT_MAX;
    
    CGFloat lineHeight = [@"A" sizeWithFont:font].height;
    return [text sizeWithFont:font constrainedToSize:CGSizeMake(width, numberOfLines * lineHeight) lineBreakMode:lineBreakMode];
}

@end

@implementation UILabel (PSStyleSheet)

+ (UILabel *)labelWithStyle:(NSString *)style {
    UILabel *l = [[UILabel alloc] initWithFrame:CGRectZero];
    [PSStyleSheet applyStyle:style forLabel:l];
    return l;
}

@end


@interface PSStyleSheet ()

+ (PSStyleSheet *)defaultStyleSheet;

@property (nonatomic, strong) NSMutableDictionary *styles;

@end

@implementation PSStyleSheet

+ (PSStyleSheet *)defaultStyleSheet {
    if (!__defaultStyleSheet) {
        __defaultStyleSheet = [[self alloc] init];
    }
    
    // Make sure we have a style sheet set
    if (!__defaultStyleSheet.styles) return nil;
    
    return __defaultStyleSheet;
}

- (id)init {
    self = [super init];
    if (self) {
        self.styles = [NSMutableDictionary dictionary];
    }
    return self;
}


#pragma mark - Config
+ (void)setStyleSheet:(NSString *)styleSheet {
    NSString *styleSheetPath = [[NSBundle mainBundle] pathForResource:styleSheet ofType:@"plist"];
    assert(styleSheetPath != nil);
    
    NSMutableDictionary *styleSheetDict = [NSMutableDictionary dictionaryWithContentsOfFile:styleSheetPath];
    assert(styleSheetDict != nil);
    
    [[[self class] defaultStyleSheet] setStyles:styleSheetDict];
}


+ (NSDictionary *)styleDictForStyle:(NSString *)style {
    // Make sure there is a style sheet loaded
    NSAssert([[self class] defaultStyleSheet].styles, @"no style sheet");
    
    return [[[self class] defaultStyleSheet].styles objectForKey:style];
}

#pragma mark - Applying Styles
+ (void)applyStyle:(NSString *)style forLabel:(UILabel *)label {
    // Determine if style exists, if it doesn't, throw an assertion
    NSAssert1([[self class] styleDictForStyle:style], @"style: %@ does not exist", style);
    
    label.font = [PSStyleSheet fontForStyle:style];
    label.minimumFontSize = [PSStyleSheet minimumFontSizeForStyle:style];
    label.textColor = [PSStyleSheet textColorForStyle:style];
    label.highlightedTextColor = [PSStyleSheet highlightedTextColorForStyle:style];
    label.shadowColor = [PSStyleSheet shadowColorForStyle:style];
    label.shadowOffset = [PSStyleSheet shadowOffsetForStyle:style];
    label.textAlignment = [PSStyleSheet textAlignmentForStyle:style];
    label.backgroundColor = [PSStyleSheet backgroundColorForStyle:style];
    label.numberOfLines = [PSStyleSheet numberOfLinesForStyle:style];
    label.lineBreakMode = [PSStyleSheet lineBreakModeForStyle:style];
    label.adjustsFontSizeToFitWidth = [PSStyleSheet adjustsFontSizeToFitWidthForStyle:style];
}

+ (void)applyStyle:(NSString *)style forButton:(UIButton *)button {
    // Determine if style exists, if it doesn't, throw an assertion
    NSAssert1([[self class] styleDictForStyle:style], @"style: %@ does not exist", style);
    
    [button setTitleColor:[PSStyleSheet textColorForStyle:style] forState:UIControlStateNormal];
    [button setTitleColor:[PSStyleSheet highlightedTextColorForStyle:style] forState:UIControlStateHighlighted];
    [button setTitleShadowColor:[PSStyleSheet shadowColorForStyle:style] forState:UIControlStateNormal];
    button.titleLabel.font = [PSStyleSheet fontForStyle:style];
    button.titleLabel.minimumFontSize = [PSStyleSheet minimumFontSizeForStyle:style];
    button.titleLabel.adjustsFontSizeToFitWidth = [PSStyleSheet adjustsFontSizeToFitWidthForStyle:style];
    button.titleLabel.shadowOffset = [PSStyleSheet shadowOffsetForStyle:style];
    button.contentHorizontalAlignment = [PSStyleSheet horizontalAlignmentForStyle:style];
}

+ (void)applyStyle:(NSString *)style forTextField:(UITextField *)textField {
    // Determine if style exists, if it doesn't, throw an assertion
    NSAssert1([[self class] styleDictForStyle:style], @"style: %@ does not exist", style);
    
    [textField setTextColor:[PSStyleSheet textColorForStyle:style]];
    [textField setFont:[PSStyleSheet fontForStyle:style]];
    [textField setTextAlignment:[PSStyleSheet textAlignmentForStyle:style]];
}

#pragma mark - Size calculation
+ (CGSize)sizeForText:(NSString *)text width:(CGFloat)width style:(NSString *)style {
    CGSize size = [UILabel sizeForText:text width:width font:[[self class] fontForStyle:style] numberOfLines:[[self class] numberOfLinesForStyle:style] lineBreakMode:[[self class] lineBreakModeForStyle:style]];
    return size;
}

#pragma mark - Fonts
+ (UIFont *)fontForStyle:(NSString *)style {
    UIFont *font = nil;
    if ([[[self class] styleDictForStyle:style] objectForKey:@"fontName"] && [[[self class] styleDictForStyle:style] objectForKey:@"fontSize"]) {
        font = [UIFont fontWithName:[[[self class] styleDictForStyle:style] objectForKey:@"fontName"] size:[[[[self class] styleDictForStyle:style] objectForKey:@"fontSize"] integerValue]];
    }
    return font;
}

+ (CGFloat)minimumFontSizeForStyle:(NSString *)style {
    CGFloat minimumFontSize = 0.0;
    if ([[[self class] styleDictForStyle:style] objectForKey:@"minimumFontSize"]) {
        minimumFontSize = [[[[self class] styleDictForStyle:style] objectForKey:@"minimumFontSize"] floatValue];
    }
    return minimumFontSize;
}

#pragma mark - Colors
+ (UIColor *)textColorForStyle:(NSString *)style {
    UIColor *color = nil;
    if ([[[self class] styleDictForStyle:style] objectForKey:@"textColor"]) {
        color = [UIColor colorWithHexString:[[[self class] styleDictForStyle:style] objectForKey:@"textColor"]];
    }
    return color;
}

+ (UIColor *)highlightedTextColorForStyle:(NSString *)style {
    UIColor *color = nil;
    if ([[[self class] styleDictForStyle:style] objectForKey:@"highlightedTextColor"]) {
        color = [UIColor colorWithHexString:[[[self class] styleDictForStyle:style] objectForKey:@"highlightedTextColor"]];
    }
    return color;
}

+ (UIColor *)shadowColorForStyle:(NSString *)style {
    UIColor *color = nil;
    if ([[[self class] styleDictForStyle:style] objectForKey:@"shadowColor"]) {
        color = [UIColor colorWithHexString:[[[self class] styleDictForStyle:style] objectForKey:@"shadowColor"]];
    }
    return color;
}

+ (UIColor *)backgroundColorForStyle:(NSString *)style {
    UIColor *color = nil;
    if ([[[self class] styleDictForStyle:style] objectForKey:@"backgroundColor"]) {
        color = [UIColor colorWithHexString:[[[self class] styleDictForStyle:style] objectForKey:@"backgroundColor"]];
    } else {
        color = [UIColor clearColor];
    }
    return color;
}

#pragma mark - Offsets
+ (CGSize)shadowOffsetForStyle:(NSString *)style {
    CGSize offset = CGSizeZero;
    if ([[[self class] styleDictForStyle:style] objectForKey:@"shadowOffset"]) {
        offset = CGSizeFromString([[[self class] styleDictForStyle:style] objectForKey:@"shadowOffset"]);
    }
    return offset;
}

#pragma mark - Text Alignment
+ (UITextAlignment)textAlignmentForStyle:(NSString *)style {
    // Defaults to UITextAlignmentLeft if undefined
    if ([[[self class] styleDictForStyle:style] objectForKey:@"textAlignment"]) {
        NSString *textAlignmentString = [[[self class] styleDictForStyle:style] objectForKey:@"textAlignment"];
        if ([textAlignmentString isEqualToString:@"center"]) {
            return UITextAlignmentCenter;
        } else if ([textAlignmentString isEqualToString:@"right"]) {
            return  UITextAlignmentRight;
        } else return UITextAlignmentLeft;
    } else {
        return UITextAlignmentLeft;
    }
}

+ (UIControlContentHorizontalAlignment)horizontalAlignmentForStyle:(NSString *)style {
    // Defaults to CENTER if undefined
    if ([[[self class] styleDictForStyle:style] objectForKey:@"textAlignment"]) {
        NSString *textAlignmentString = [[[self class] styleDictForStyle:style] objectForKey:@"textAlignment"];
        if ([textAlignmentString isEqualToString:@"center"]) {
            return UIControlContentHorizontalAlignmentCenter;
        } else if ([textAlignmentString isEqualToString:@"right"]) {
            return  UIControlContentHorizontalAlignmentRight;
        } else return UIControlContentHorizontalAlignmentLeft;
    } else {
        return UIControlContentHorizontalAlignmentCenter;
    }
}

#pragma mark - Number of Lines
+ (NSInteger)numberOfLinesForStyle:(NSString *)style {
    NSInteger numberOfLines = 0; // If left empty, default to 0
    if ([[[[self class] styleDictForStyle:style] objectForKey:@"numberOfLines"] integerValue]) {
        numberOfLines = [[[[self class] styleDictForStyle:style] objectForKey:@"numberOfLines"] integerValue];
    }
    return numberOfLines;
}

#pragma mark - Line break mode
+ (UILineBreakMode)lineBreakModeForStyle:(NSString *)style {
    //  typedef enum {		
    //    UILineBreakModeWordWrap = 0,            // Wrap at word boundaries
    //    UILineBreakModeCharacterWrap,           // Wrap at character boundaries
    //    UILineBreakModeClip,                    // Simply clip when it hits the end of the rect
    //    UILineBreakModeHeadTruncation,          // Truncate at head of line: "...wxyz". Will truncate multiline text on first line
    //    UILineBreakModeTailTruncation,          // Truncate at tail of line: "abcd...". Will truncate multiline text on last line
    //    UILineBreakModeMiddleTruncation,        // Truncate middle of line:  "ab...yz". Will truncate multiline text in the middle
    //  } UILineBreakMode;
    UILineBreakMode lineBreakMode = UILineBreakModeTailTruncation;
    if ([[[self class] styleDictForStyle:style] objectForKey:@"lineBreakMode"]) {
        NSString *lineBreakModeString = [[[self class] styleDictForStyle:style] objectForKey:@"lineBreakMode"];
        if ([lineBreakModeString isEqualToString:@"wordWrap"]) {
            lineBreakMode = UILineBreakModeWordWrap;
        } else if ([lineBreakModeString isEqualToString:@"characterWrap"]) {
            lineBreakMode = UILineBreakModeCharacterWrap;
        } else {
            lineBreakMode = UILineBreakModeTailTruncation;
        }
    }
    return lineBreakMode;
}

+ (BOOL)adjustsFontSizeToFitWidthForStyle:(NSString *)style {
    BOOL adjustsFontSizeToFitWidth = NO;
    if ([[[self class] styleDictForStyle:style] objectForKey:@"adjustsFontSizeToFitWidth"]) {
        adjustsFontSizeToFitWidth = [[[[self class] styleDictForStyle:style] objectForKey:@"adjustsFontSizeToFitWidth"] boolValue];
    }
    return adjustsFontSizeToFitWidth;
}

@end