import type { Artifact } from "./types/artifact.js";
export declare const YAML_FRONTMATTER_MARKER = "---";
export declare const LEADING_ENCODING_BOM = "\uFEFF";
export type FrontmatterContract = "agent-skill" | "renma";
export interface FrontmatterEnvelope {
    present: boolean;
    closingIndex: number | undefined;
}
export interface LeadingEncodingBomResult {
    content: string;
    consumed: boolean;
}
/** Consume at most one absolute leading encoding BOM. */
export declare function consumeOneLeadingEncodingBom(line: string): LeadingEncodingBomResult;
/** Normalize only syntax that the selected opener contract already accepts. */
export declare function normalizeFrontmatterOpener(line: string, contract: FrontmatterContract): string;
/** Test an opener without granting authority to a sanitized approximation. */
export declare function isFrontmatterOpener(line: string, contract: FrontmatterContract): boolean;
/** Test a closer under the selected, intentionally distinct contract. */
export declare function isFrontmatterCloser(line: string, contract: FrontmatterContract): boolean;
/**
 * Return the opener text inspected for bounded corruption evidence.
 *
 * Renma's one accepted absolute encoding BOM is excluded before integrity
 * projection. Agent Skills retain their established whitespace/BOM contract.
 * The returned text is evidence only and must never be parsed for authority.
 */
export declare function frontmatterOpenerIntegrityInput(line: string, contract: FrontmatterContract): string;
/** Locate one envelope without parsing or repairing its contents. */
export declare function frontmatterEnvelope(lines: readonly string[], contract: FrontmatterContract): FrontmatterEnvelope;
/**
 * Locate an Agent Skills YAML envelope without parsing its contents.
 *
 * The opening delimiter retains the established BOM and surrounding-whitespace
 * handling. A closing delimiter must begin in column one, but may retain
 * trailing whitespace. Indented delimiter-looking text therefore remains YAML
 * content, including inside block scalars.
 */
export declare function agentSkillFrontmatterEnvelope(lines: readonly string[]): FrontmatterEnvelope;
/**
 * Locate the general Renma metadata envelope after consuming one absolute
 * leading Unicode BOM. The delimiter itself remains exact: visible whitespace
 * and any remaining characters are noncanonical.
 */
export declare function renmaFrontmatterEnvelope(lines: readonly string[]): FrontmatterEnvelope;
/** Select the frontmatter contract from the artifact's discovered role. */
export declare function frontmatterEnvelopeForArtifact(artifact: Pick<Artifact, "kind">, lines: readonly string[]): FrontmatterEnvelope;
/** Return the Markdown body start while preserving unclosed-envelope behavior. */
export declare function markdownBodyStartLineForArtifact(artifact: Pick<Artifact, "kind">, lines: readonly string[]): number;
/** Return a closed frontmatter range under the artifact-selected contract. */
export declare function frontmatterRangeForArtifact(artifact: Pick<Artifact, "kind">, lines: readonly string[]): {
    startLine: number;
    endLine: number;
} | undefined;