//
//  DTCoreTextLayoutLine.h
//  WeRead
//
//  Reverse-engineered from binary analysis
//  Based on DTCoreText open-source library, customized by WeRead
//
//  DTCoreText is an open-source library for rendering HTML with CoreText.
//  This class represents a single line of laid-out text.
//

#import <Foundation/Foundation.h>
#import <CoreText/CoreText.h>

@class DTCoreTextGlyphRun;
@class DTCoreTextLayoutFrame;

NS_ASSUME_NONNULL_BEGIN

/**
 * DTCoreTextLayoutLine - Represents a single line of laid-out text.
 *
 * This class wraps CTLine and provides high-level access to the
 * layout of a single line. It contains an array of DTCoreTextGlyphRun objects
 * and provides methods for accessing typographic metrics and hit testing.
 *
 * Key features:
 * - Wraps CTLine for high-level access
 * - Contains array of DTCoreTextGlyphRun objects
 * - Provides typographic metrics (ascent, descent, leading, width)
 * - Supports hit testing within the line
 * - Handles baseline offsets for superscript/subscript
 */
@interface DTCoreTextLayoutLine : NSObject

#pragma mark - Properties

/** The CTLine reference */
@property (nonatomic, assign, readonly) CTLineRef ctLine;

/** The origin point of this line in the frame */
@property (nonatomic, assign) CGPoint origin;

/** The range of characters in this line */
@property (nonatomic, assign, readonly) NSRange stringRange;

/** The index of this line in the frame */
@property (nonatomic, assign, readonly) NSUInteger lineIndex;

/** Ascent of the line */
@property (nonatomic, assign, readonly) CGFloat ascent;

/** Descent of the line */
@property (nonatomic, assign, readonly) CGFloat descent;

/** Leading of the line */
@property (nonatomic, assign, readonly) CGFloat leading;

/** Total height of the line (ascent + descent + leading) */
@property (nonatomic, assign, readonly) CGFloat height;

/** Width of the line */
@property (nonatomic, assign, readonly) CGFloat width;

/** Trailing whitespace width */
@property (nonatomic, assign, readonly) CGFloat trailingWhitespaceWidth;

/** Array of glyph runs in this line */
@property (nonatomic, strong, readonly) NSArray<DTCoreTextGlyphRun *> *glyphRuns;

/** The baseline offset (for superscript/subscript) */
@property (nonatomic, assign) CGFloat baselineOffset;

/** Whether this line is the last line in a paragraph */
@property (nonatomic, assign) BOOL isLastLineInParagraph;

/** Whether this line is a line break */
@property (nonatomic, assign) BOOL isLineBreak;

/** The paragraph style for this line */
@property (nonatomic, strong, nullable) NSDictionary *paragraphStyle;

/** Additional metrics for the line */
@property (nonatomic, strong, nullable) NSDictionary *metrics;

#pragma mark - Initialization

/**
 * Initialize with a CTLine and origin.
 *
 * @param ctLine The CoreText line
 * @param origin The origin point
 * @param range The string range
 * @param index The line index
 * @return Initialized layout line
 */
- (instancetype)initWithCTLine:(CTLineRef)ctLine
                        origin:(CGPoint)origin
                         range:(NSRange)range
                         index:(NSUInteger)index;

#pragma mark - Glyph Run Access

/**
 * Returns the array of glyph runs.
 *
 * @return Array of DTCoreTextGlyphRun objects
 */
- (NSArray<DTCoreTextGlyphRun *> *)glyphRuns;

/**
 * Returns the glyph run at the specified index.
 *
 * @param index The glyph run index
 * @return The glyph run at the index, or nil
 */
- (nullable DTCoreTextGlyphRun *)glyphRunAtIndex:(NSUInteger)index;

/**
 * Returns the glyph run containing the given string index.
 *
 * @param index The string index
 * @return The glyph run containing the index, or nil
 */
- (nullable DTCoreTextGlyphRun *)glyphRunContainingStringIndex:(NSUInteger)index;

#pragma mark - Typographic Metrics

/**
 * Returns the typographic bounds of the line.
 *
 * @param ascent Output parameter for ascent
 * @param descent Output parameter for descent
 * @param leading Output parameter for leading
 * @return The width of the line
 */
- (CGFloat)getTypographicBoundsAscent:(CGFloat *)ascent
                              descent:(CGFloat *)descent
                              leading:(CGFloat *)leading;

/**
 * Returns the bounds of the line (bounding box).
 */
- (CGRect)bounds;

/**
 * Returns the frame of the line (position + bounds).
 */
- (CGRect)frame;

#pragma mark - Hit Testing

/**
 * Returns the string index at the given point within this line.
 *
 * @param point The point to test (in the line's coordinate system)
 * @return The string index, or NSNotFound
 */
- (NSUInteger)stringIndexAtPoint:(CGPoint)point;

/**
 * Returns the offset for a given string index.
 *
 * @param index The string index
 * @return The horizontal offset
 */
- (CGFloat)offsetForStringIndex:(NSUInteger)index;

/**
 * Returns the rect for a given string index.
 *
 * @param index The string index
 * @return The rect for the character
 */
- (CGRect)rectForStringIndex:(NSUInteger)index;

#pragma mark - String Operations

/**
 * Returns the substring represented by this line.
 */
- (nullable NSString *)substringFromAttributedString:(NSAttributedString *)attributedString;

/**
 * Returns the attributes at a given string index.
 */
- (nullable NSDictionary *)attributesAtIndex:(NSUInteger)index
                       fromAttributedString:(NSAttributedString *)attributedString;

#pragma mark - Line Comparison

/**
 * Compares this line to another line for ordering.
 */
- (NSComparisonResult)compareToLine:(DTCoreTextLayoutLine *)otherLine;

/**
 * Returns whether this line contains the given string index.
 */
- (BOOL)containsStringIndex:(NSUInteger)index;

/**
 * Returns whether this line intersects with the given range.
 */
- (BOOL)intersectsRange:(NSRange)range;

#pragma mark - Drawing

/**
 * Draws this line into a CGContext.
 *
 * @param context The CGContext to draw into
 */
- (void)drawInContext:(CGContextRef)context;

/**
 * Draws this line with a specific color.
 *
 * @param context The CGContext to draw into
 * @param color The text color
 */
- (void)drawInContext:(CGContextRef)context withColor:(UIColor *)color;

@end

NS_ASSUME_NONNULL_END