import type { FlowNode } from "../types.js";
import type { BuildApi, BuilderMethod, Edge, EmitApi, LoopCtx } from "../declarative.js";
/** Recurse the tree walker into a node's nested bodies (see `walkNodes`). */
export type WalkRecurse = (body: FlowNode[]) => void;
/** The three handlers a flow-node kind contributes. `N` is the kind's own
 *  `FlowNode` variant (narrowed from the union by the registry key). */
export interface NodeKindHandlers<N extends FlowNode = FlowNode> {
    /** Factory for the `FlowBuilder` method that appends this kind's node. Given
     *  the per-body {@link BuildApi}, returns the method installed on the builder
     *  as `w.<builderMethod ?? kind>`. Omit for a kind with no authoring method. */
    build?: (api: BuildApi) => BuilderMethod;
    /** The builder method name, when it differs from the kind (defaults to the
     *  kind). */
    builderMethod?: string;
    /** Depth-first recursion into the node's nested bodies. Omit for a leaf. */
    walk?: (node: N, recurse: WalkRecurse) => void;
    /** Emit this node into the BPMN graph, returning the outgoing (dangling)
     *  edges its continuation attaches to. */
    emit: (node: N, incoming: Edge[], loop: LoopCtx | null, api: EmitApi) => Edge[];
}
/** Register the handlers for one flow-node kind. Called once, at module import
 *  time, from `src/nodes/<kind>.ts`. */
export declare function registerNodeKind<K extends FlowNode["kind"]>(kind: K, handlers: NodeKindHandlers<Extract<FlowNode, {
    kind: K;
}>>): void;
/** The handlers registered for a kind, or `undefined` if none. */
export declare function nodeKind(kind: string): NodeKindHandlers | undefined;
/** The registered kind, or a thrown error naming the unknown kind — used by the
 *  emitter, which cannot proceed without a handler. */
export declare function requireNodeKind(kind: string): NodeKindHandlers;
/** Every registered kind + its handlers, in registration order. Used by
 *  `makeBuilder` to install each kind's builder method. */
export declare function eachNodeKind(): Iterable<[string, NodeKindHandlers]>;