import type { TreeCheckedState } from '../tree/types.cjs';
import type { TreeSelectCheckStrategy, TreeSelectNode, TreeSelectValueStrategy } from './types.cjs';
/** Pure functions for cascading check state, value projection and filtering; no React/DOM, works on collapsed branches. */
/** @internal Everything derived once per collection about a single node. */
export interface TreeSelectIndexEntry {
    node: TreeSelectNode;
    /** Parent's value, or `null` for a root node. */
    parent: string | null;
    /** 1-based depth, which is exactly `aria-level`. */
    depth: number;
    /** Immediate children's values, in collection order. */
    childValues: string[];
    /** Every descendant's value, in pre-order. */
    descendants: string[];
    /** Enabled leaf descendants this node's tri-state derives from, excluding disabled leaves so one doesn't stick a branch at 'mixed'. */
    leaves: string[];
    /** Own `disabled`, or any ancestor's — disabling a branch disables its subtree. */
    disabled: boolean;
}
/** @internal Value → entry, built once per `collection` identity. */
export type TreeSelectIndex = ReadonlyMap<string, TreeSelectIndexEntry>;
/** @internal One row of the visible, expanded tree, in the order the arrow keys walk it. */
export interface TreeSelectFlatNode {
    value: string;
    parent: string | null;
    depth: number;
    disabled: boolean;
    /** Whether it has a visible child or declares itself a branch via `hasChildren`; decides `aria-expanded`. */
    hasChildren: boolean;
    expanded: boolean;
    /** 1-based position among its visible siblings — `aria-posinset`. */
    posinset: number;
    /** Number of visible siblings including itself — `aria-setsize`. */
    setsize: number;
}
/** @internal Flattens a collection into a value-keyed index plus its pre-order value list. */
export declare function indexCollection(collection: readonly TreeSelectNode[]): {
    index: Map<string, TreeSelectIndexEntry>;
    order: string[];
};
/** @internal A node's ancestors, nearest first. */
export declare function ancestorsOf(value: string, index: TreeSelectIndex): string[];
/** @internal The value strategy that can round-trip under `strategy`, falling back to `'all'` when the matching propagation direction is missing. */
export declare function effectiveValueStrategy(strategy: TreeSelectCheckStrategy, valueStrategy: TreeSelectValueStrategy): TreeSelectValueStrategy;
/** @internal A node's tri-state value: plain membership under `'independent'`, else derived from its enabled leaves. */
export declare function checkStateOf(value: string, checked: ReadonlySet<string>, index: TreeSelectIndex, strategy: TreeSelectCheckStrategy): TreeCheckedState;
/** @internal Expands an emitted `value` back into the full checked set; the inverse of {@link projectValue}, and the pair must round-trip. */
export declare function normalizeChecked(values: readonly string[], index: TreeSelectIndex, order: readonly string[], strategy: TreeSelectCheckStrategy): Set<string>;
/** @internal Reduces the full checked set to the values a consumer actually receives. */
export declare function projectValue(checked: ReadonlySet<string>, index: TreeSelectIndex, order: readonly string[], strategy: TreeSelectValueStrategy): string[];
/** @internal The checked set after activating one node. */
export declare function toggleChecked(value: string, checked: ReadonlySet<string>, index: TreeSelectIndex, strategy: TreeSelectCheckStrategy, multiple: boolean): Set<string>;
/** @internal Which nodes survive the filter and which branches must open to reveal them; a match drags its ancestor chain and subtree into visibility. */
export declare function computeFilter(index: TreeSelectIndex, order: readonly string[], matches: (node: TreeSelectNode) => boolean): {
    visible: Set<string>;
    autoExpanded: Set<string>;
    matchCount: number;
};
/** @internal Walks the visible collection in navigation order, descending only into expanded branches. */
export declare function flattenVisible(collection: readonly TreeSelectNode[], index: TreeSelectIndex, visible: ReadonlySet<string> | null, expanded: ReadonlySet<string>): TreeSelectFlatNode[];