/**
 * Per-chunk configuration. Sensible defaults — callers rarely override.
 */
export interface ChunkerConfig {
    /** Soft max size (chars) for a single chunk. Oversized sections get split. */
    chunkSize: number;
    /** Heading depth we still split on (H1..Hn). Beyond this, a section stays atomic. */
    headingSplitDepth: number;
    /** Keep fenced code blocks whole even if oversized. */
    preserveCodeBlocks: boolean;
    /** Keep $$...$$ LaTeX blocks whole even if oversized. */
    preserveLatexBlocks: boolean;
    /** Drop chunks shorter than this after trimming. */
    minChunkChars: number;
}
/**
 * Build the default chunker config. `chunkBudgetChars` — sourced from
 * capacity.ts at runtime — should be passed as `chunkSize` by callers.
 * The fallback of 1000 chars is retained only for backward-compat in tests
 * and callers that don't yet have a capacity object; it no longer represents
 * a hardcoded model-family limit.
 *
 * Env override: OBSIDIAN_BRAIN_MAX_CHUNK_TOKENS (handled in capacity.ts).
 * Callers that pass `chunkBudgetChars` from getCapacity() automatically
 * honour the env var because getCapacity() reads it first.
 */
export declare const DEFAULT_CHUNKER_CONFIG: ChunkerConfig;
/**
 * Build a ChunkerConfig from a capacity-provided char budget. Inherits all
 * other defaults from DEFAULT_CHUNKER_CONFIG so callers only need to supply
 * what varies.
 */
export declare function chunkerConfigFromBudget(chunkBudgetChars: number): ChunkerConfig;
/**
 * A single emitted chunk. `chunkIndex` is the ordinal within the parent note,
 * `contentHash` is a stable fingerprint over heading + content so the indexer
 * can skip re-embedding an unchanged chunk.
 */
export interface Chunk {
    chunkIndex: number;
    heading: string | null;
    headingLevel: number | null;
    content: string;
    contentHash: string;
    startLine: number;
    endLine: number;
}
/**
 * Split a markdown document into embedding-sized chunks.
 *
 * Strategy:
 *   1. Strip frontmatter.
 *   2. Replace protected regions (code fences + $$...$$) with sentinel tokens
 *      so later splits can't cut them in half.
 *   3. Segment by headings up to `headingSplitDepth`.
 *   4. For oversize sections, recursively split on paragraph → sentence → hard.
 *   5. Restore protected regions. Emit Chunks.
 */
export declare function chunkMarkdown(content: string, config?: ChunkerConfig): Chunk[];
/**
 * Build the text we actually feed to the embedder for a chunk. Heading is
 * prepended so semantic queries line up with heading-anchored content.
 */
export declare function buildChunkEmbeddingText(chunk: Chunk): string;
/**
 * Build the stable chunk id from the parent node's id and the chunk index.
 * Uses `::` as the separator — node ids are file paths (no `::`) so this
 * is collision-safe.
 */
export declare function chunkId(nodeId: string, chunkIndex: number): string;