include/rive/text/line_break.hpp

/*
 * Copyright 2026 Rive
 */

#ifndef _RIVE_LINE_BREAK_HPP_
#define _RIVE_LINE_BREAK_HPP_

#include "rive/span.hpp"
#include <cstdint>

namespace rive
{

// UAX #14 line break classes after LB1 resolution (AI, SG, XX and SA never
// appear). Order must match CLASSES in dev/unicode/generate_line_break.py.
enum class LineBreakClass : uint8_t
{
  AL,
  AK,
  AP,
  AS,
  B2,
  BA,
  BB,
  BK,
  CB,
  CJ,
  CL,
  CM,
  CP,
  CR,
  EB,
  EM,
  EX,
  GL,
  H2,
  H3,
  HH,
  HL,
  HY,
  ID,
  IN,
  IS,
  JL,
  JT,
  JV,
  LF,
  NL,
  NS,
  NU,
  OP,
  PO,
  PR,
  QU,
  RI,
  SP,
  SY,
  VF,
  VI,
  WJ,
  ZW,
  ZWJ,
};

// Extra properties some rules need beyond the class. Values must match the
// FLAG_ constants in the generator.
enum LineBreakFlags : uint8_t
{
  lineBreakEastAsian = 1,      // East_Asian_Width is F, W or H
  lineBreakPi = 2,             // General_Category Pi
  lineBreakPf = 4,             // General_Category Pf
  lineBreakDottedCircle = 8,   // U+25CC
  lineBreakPictographicCn = 16 // Extended_Pictographic and unassigned
};

struct LineBreakProps
{
  LineBreakClass cls;
  uint8_t flags;
};

LineBreakProps lineBreakProps(uint32_t codepoint);

enum class LineBreak : uint8_t
{
  none,      // no break allowed at this boundary
  allowed,   // break opportunity
  mandatory, // hard break
};

// Computes the break status of every boundary in text. out must hold
// text.size() + 1 entries: out[i] is the boundary before codepoint i and
// out[0] is always none. End of text is always a break (LB3), reported as
// mandatory only when the last codepoint is itself a hard break so callers
// can tell a trailing empty line apart.
void computeLineBreaks(Span<const uint32_t> text, Span<LineBreak> out);

} // namespace rive
#endif