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//! Threshold constants for PDF-to-Markdown spatial analysis.
// ~keep ── Glyph-fragmentation repair (issue #962) ────────────────────────────────
// ~keep
// ~keep Word-exported PDFs position each glyph via its own BT…ET block with a
// ~keep sinusoidal y-jitter (~3–5 pt amplitude, 6-glyph period). pdf_oxide's
// ~keep ColumnAware reading order groups spans by y-level, scrambling reading
// ~keep order for these documents. The constants below parameterise the
// ~keep detection and reconstruction heuristic in `pdf::oxide::text`.
/// Maximum y-gap (pt) between two spans that can still be considered "same
/// line" under the glyph-fragmentation detection heuristic.
///
/// Word's sinusoidal jitter (6-glyph period, ~3 pt amplitude) produces
/// consecutive-pair y-gaps of ≤ ~3.03 pt. 5 pt adds headroom for atypical
/// Word configurations while remaining well below normal body-text leading
/// (~12–14 pt). Using an absolute ceiling instead of a font-size fraction
/// avoids the false-positive zone where `font_size * 0.25` (the old
/// fallback) overlaps with normal tight leading for larger fonts.
pub const MAX_GLYPH_JITTER_PT: f32 = 5.0;
/// Minimum qualifying x-disorder events before classifying a span list as
/// glyph-fragmented.
///
/// A 32-char Word jitter word (period 6, 3 distinct y-levels) produces
/// exactly 4 disorder events. Requiring ≥ 3 is sufficient to detect all
/// jitter amplitudes ≥ 3 pt while being robust against false positives:
/// the short-span guard (≤ 3 chars) and the 5 pt same-line ceiling
/// together make it essentially impossible for normal multi-column text
/// to accumulate 3 consecutive qualifying resets.
pub const MIN_DISORDER_COUNT: usize = 3;
/// y-proximity threshold (pt) for grouping spans into visual lines during
/// reconstruction. Must be ≥ MAX_GLYPH_JITTER_PT so every span pair
/// accepted by the detection gate is merged into the same group.
pub const COALESCE_THRESHOLD: f32 = 5.0;
/// Maximum word count for a paragraph to qualify as a heading.
pub const MAX_HEADING_WORD_COUNT: usize = 20;
/// Maximum distance multiplier relative to average inter-cluster gap for heading assignment.
pub const MAX_HEADING_DISTANCE_MULTIPLIER: f32 = 2.0;
/// Minimum ratio of heading font size to body font size (heading must be this much larger).
/// 1.15 captures LaTeX \subsection (12pt vs 10pt body = 1.2 ratio).
pub const MIN_HEADING_FONT_RATIO: f32 = 1.15;
/// Minimum absolute font-size difference (in points) between heading and body.
/// 1.5pt captures academic sub-headings (11.5pt vs 10pt body).
pub const MIN_HEADING_FONT_GAP: f32 = 1.5;
/// Maximum word count for a bold paragraph to be promoted to a section heading.
pub const MAX_BOLD_HEADING_WORD_COUNT: usize = 12;
/// Minimum layout-hint confidence required for a `Text`/`Caption`/`Footnote` hint to
/// *demote* an existing heading to body text. Demotion is destructive — erasing a real
/// heading costs a 2.0-weight block in SF1 — so it uses a higher bar than the 0.5/0.7
/// thresholds used for constructive overrides, and additionally requires the paragraph
/// to carry no independent heading evidence (font-above-body, bold, or a section pattern).
pub const HEADING_DEMOTE_CONFIDENCE: f32 = 0.85;
/// Minimum number of non-empty text blocks a document must contain before
/// font-size clustering is allowed to promote any run to a heading.
///
/// Font-size heading inference is only reliable once there is enough text to
/// establish a stable body-font baseline. In a document with only a handful of
/// blocks (a title slide, a cover page, a one-line note) a single larger line is
/// far more likely to be display/opening prose than a section heading, so
/// promoting it costs the structural-F1 metric heavily (headings are weighted
/// 2.0). Below this floor, `build_heading_map` returns a body-only map and the
/// fallback title promotion is skipped. The floor is set so a genuine short
/// document (title plus four body paragraphs, five blocks) still gets its
/// heading, while two- or three-block fixtures do not.
pub const MIN_BLOCKS_FOR_FONT_HEADING: usize = 5;
/// Fraction of the maximum right edge that a line must reach to be considered "full"
/// (used for dehyphenation to avoid false joins on short/indented lines).
pub const FULL_LINE_FRACTION: f32 = 0.85;