import { SqlComponent } from "../models/SqlComponent";
/**
 * Source span for a comment when parser metadata is available.
 *
 * @remarks The current parser stores comment text on AST nodes but does not
 * retain reliable per-comment source spans, so extractors usually omit this.
 */
export interface AstCommentSourceRange {
    start: number;
    end: number;
}
/**
 * Conservatively describes where an AST comment fact appears relative to syntax.
 */
export type AstCommentPlacement = "leading" | "trailing" | "inner" | "detached";
/**
 * Generic comment fact extracted from SQL AST comment metadata.
 *
 * @remarks `targetNode` is optional because SQL comments do not always have a
 * strict syntactic owner. Ambiguous legacy buckets are emitted as detached.
 */
export interface AstCommentAttachment {
    text: string;
    sourceOrder: number;
    placement: AstCommentPlacement;
    targetNode?: SqlComponent;
    range?: AstCommentSourceRange;
}
/**
 * Extracts comment attachment facts already represented in the SQL AST.
 *
 * @remarks This API does not infer product-specific meanings or rewrite
 * comments. It returns a deterministic flat list without mutating the input AST.
 */
export declare class AstCommentAttachmentExtractor {
    private readonly attachments;
    private readonly visited;
    private readonly suppressedDetachedCommentArrays;
    /**
     * Extract comment attachment facts from a SQL AST component.
     */
    static extract(input: SqlComponent | null | undefined): AstCommentAttachment[];
    private visit;
    private visitSqlComponent;
    private visitFallbackProperties;
    private shouldSkipProperty;
    private emitHeaderComments;
    private emitLegacyComments;
    private emitPositionedComments;
    private emitSelectItemKeywordComments;
    private emitKeywordPositionedComments;
    private emitDetachedComments;
    private emitComments;
    private isSelectQuery;
    private suppressWithClauseTrailingCommentsAlreadyCopiedToQuery;
    private containsCommentSequence;
}
/**
 * Extract comment attachment facts from a SQL AST component.
 */
export declare function extractAstCommentAttachments(input: SqlComponent | null | undefined): AstCommentAttachment[];