import { GlyphBuffer } from "../buffer/glyph-buffer.ts";
import type { Font } from "../font/font.ts";
import type { GlyphId, Tag } from "../types.ts";
/**
 * Justification mode
 */
export declare enum JustifyMode {
    /** Shrink text to fit */
    Shrink = "shrink",
    /** Extend text to fit */
    Extend = "extend",
    /** Auto-select based on delta */
    Auto = "auto"
}
/**
 * Justification options
 */
export interface JustifyOptions {
    /** Target line width */
    targetWidth: number;
    /** Script tag */
    script?: Tag;
    /** Language tag */
    language?: Tag;
    /** Justification mode */
    mode?: JustifyMode;
    /** Maximum priority level to use (0-based) */
    maxPriority?: number;
    /** Enable Kashida insertion for Arabic */
    enableKashida?: boolean;
    /** Minimum word spacing factor (default: 0.8) */
    minWordSpacingFactor?: number;
    /** Maximum word spacing factor (default: 1.5) */
    maxWordSpacingFactor?: number;
    /** Enable inter-character spacing adjustment */
    enableLetterSpacing?: boolean;
    /** Maximum letter spacing in font units */
    maxLetterSpacing?: number;
}
/**
 * Justification result
 */
export interface JustifyResult {
    /** Whether justification succeeded */
    success: boolean;
    /** Final line width after justification */
    finalWidth: number;
    /** Delta from target (positive = too wide, negative = too narrow) */
    delta: number;
    /** Priority level used */
    priorityLevel: number;
    /** Adjustments applied */
    adjustments: JustifyAdjustment[];
}
/**
 * Individual justification adjustment
 */
export interface JustifyAdjustment {
    type: "spacing" | "kashida" | "lookup";
    /** Glyph indices affected */
    glyphIndices: number[];
    /** Adjustment value */
    value: number;
}
/**
 * Calculate current line width from glyph buffer
 * @param buffer - The glyph buffer to measure
 * @returns Total line width in font units (sum of all xAdvance values)
 */
export declare function calculateLineWidth(buffer: GlyphBuffer): number;
/**
 * Justify a shaped glyph buffer to fit a target width
 * @param font - The font containing JSTF and glyph metrics
 * @param buffer - The shaped glyph buffer to justify (modified in place)
 * @param options - Justification options including target width and mode
 * @returns Result containing success status, final width, and applied adjustments
 */
export declare function justify(font: Font, buffer: GlyphBuffer, options: JustifyOptions): JustifyResult;
/**
 * Simple line breaking for multi-line text
 */
export interface LineBreakResult {
    lines: GlyphBuffer[];
    breakPoints: number[];
}
/**
 * Break shaped text into lines at a given width using simple greedy algorithm
 * @param buffer - The shaped glyph buffer to break into lines
 * @param maxWidth - Maximum line width in font units
 * @param spaceGlyph - Optional glyph ID of space character for word boundary detection
 * @returns Object containing array of line buffers and break point indices
 */
export declare function breakIntoLines(buffer: GlyphBuffer, maxWidth: number, spaceGlyph?: GlyphId): LineBreakResult;
/**
 * Justify all lines in a paragraph to the same width
 * @param font - The font containing JSTF and glyph metrics
 * @param lines - Array of glyph buffers representing lines (modified in place)
 * @param options - Justification options including target width and mode
 * @returns Array of justification results, one per line
 */
export declare function justifyParagraph(font: Font, lines: GlyphBuffer[], options: JustifyOptions): JustifyResult[];