/**
 * AST transform that applies an {@link ExtensionRouter}.
 *
 * Unlike the schema transform — which only rewrites string *fields* already
 * present on a node — moving an extension changes the **shape** of the AST:
 *
 * - `CREATE EXTENSION <e>` with no `SCHEMA` clause must gain one, which means
 *   constructing a new `DefElem` node and attaching it to a (possibly absent)
 *   `options` array; the reverse strips the `DefElem` (and empties `options`).
 * - a bare `crypt(...)` reference gains a schema qualifier (a `String` node is
 *   prepended to `funcname`), and the reverse removes it.
 *
 * All rewrites are AST-precise and driven by the router's version-aware symbol
 * inventory, so built-ins that merely share a name with an extension symbol
 * (and symbols that have graduated into core) are left untouched.
 */
import type { ExtensionRouterOptions, ExtensionRouteSpec } from './extension-router';
import { ExtensionRouter } from './extension-router';
/** What an extension transform changed. */
export interface ExtensionTransformResult {
    /** Extensions whose install schema was rewritten: extname -> target (null = unqualified). */
    installsMoved: Map<string, string | null>;
    /** Symbol references rewritten, counted by bare symbol name. */
    symbolsRewritten: Map<string, number>;
}
/** Create a fresh result tracker. */
export declare function createExtensionResult(): ExtensionTransformResult;
/**
 * Create a SQL AST visitor that applies extension routing. Composable with the
 * walkers used by the core transform and by PL/pgSQL body traversal.
 */
export declare function createExtensionVisitor(router: ExtensionRouter, result: ExtensionTransformResult): {
    CreateExtensionStmt: (path: any) => void;
    AlterObjectSchemaStmt: (path: any) => void;
    FuncCall: (path: any) => void;
    CallStmt: (path: any) => void;
    TypeName: (path: any) => void;
    CreateFunctionStmt: (path: any) => void;
};
/**
 * Apply extension routing to a SQL string: parse -> walk -> deparse, including
 * PL/pgSQL and `LANGUAGE sql` bodies. Returns the rewritten SQL and a summary
 * of what changed.
 */
export declare function transformExtensions(sql: string, router: ExtensionRouter | ExtensionRouteSpec, options?: ExtensionRouterOptions): {
    sql: string;
    result: ExtensionTransformResult;
};