import { EastTypeValue, PatchLeafOp } from '@elaraai/east';
export type LeafOp = PatchLeafOp;
/** A leaf change — one user-visible before/after pair. */
export interface LeafNode {
    kind: "leaf";
    /** Stringified PatchPath — stable id within the binding. */
    path: string;
    /** Last segment, for display. */
    label: string;
    op: LeafOp;
    leafType: EastTypeValue | null;
    before: any;
    after: any;
    /** Set when the patch's expectation at this leaf disagrees with the
     *  actual base value (overlay-mode drift). When present, the row should
     *  render a warning badge with `actual` so the user can see what the
     *  source has now vs what the patch expected. */
    stale?: {
        expected: unknown;
        actual: unknown;
    };
}
/** An interior change — wraps multiple leaf or group children. */
export interface GroupNode {
    kind: "group";
    /** Stringified PatchPath. */
    path: string;
    /** Last segment, for display. */
    label: string;
    /** Total leaves under this subtree. */
    leafCount: number;
    /** Flat list of every leaf path under this subtree. Pre-computed during
     *  walk so the renderer's "discard all" handler doesn't re-traverse on
     *  each render. */
    subtreeLeafPaths: string[];
    children: DiffNode[];
}
export type DiffNode = LeafNode | GroupNode;
/** Enumerate all leaves under a node — used for total-count tallies that
 *  need {@link LeafNode} objects (not just paths). */
export declare function collectLeaves(node: DiffNode, into?: LeafNode[]): LeafNode[];
/**
 * Walk a patch and build the renderer's `DiffNode` tree. Returns `null` when
 * the patch is unchanged (no events fire).
 *
 * @param typeValue - Runtime EastTypeValue of the value being patched.
 * @param patch     - The patch (`PatchTypeOf<T>`).
 * @param rootLabel - Display label for the root node (the renderer fills in
 *   the binding name here).
 */
export declare function walkPatchToTree(typeValue: EastTypeValue, patch: any, rootLabel: string): DiffNode | null;
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