import * as _angular_core from '@angular/core';
import { TemplateRef } from '@angular/core';
import { ControlValueAccessor } from '@angular/forms';

/** One node in the cascader tree. */
interface WrCascaderOption<T = string> {
    /** Value contributed when this node is part of the selection path. */
    readonly value: T;
    /** Display label for this node. */
    readonly label: string;
    /** Disable interaction for this node. @default false */
    readonly disabled?: boolean;
    /** Children. Absence (or empty array) marks this as a leaf. */
    readonly children?: readonly WrCascaderOption<T>[];
}

/**
 * Multi-level select — drills down through hierarchical categories
 * (e.g. country → state → city). Each level renders as a column; clicks
 * advance to the next column. Selecting a leaf (no children) commits
 * the full path.
 *
 * Implements `ControlValueAccessor` — value is the path through the
 * tree as a `readonly T[]`.
 *
 * @example
 * ```html
 * <wr-cascader [options]="locations" [(ngModel)]="path" placeholder="Pick a location" />
 * ```
 *
 * ```ts
 * locations: WrCascaderOption[] = [
 *   {
 *     value: 'us', label: 'United States', children: [
 *       { value: 'ny', label: 'New York', children: [
 *         { value: 'nyc', label: 'NYC' },
 *         { value: 'buf', label: 'Buffalo' },
 *       ] },
 *     ],
 *   },
 * ];
 * ```
 *
 * @see https://ngwr.dev/components/cascader
 */
type WrCascaderSize = 'sm' | 'md' | 'lg';
declare class WrCascader<T = string> implements ControlValueAccessor {
    /** Root-level options. Each may have `children` for deeper levels. */
    readonly options: _angular_core.InputSignal<readonly WrCascaderOption<T>[]>;
    /** Placeholder shown when no path is selected. @default '' */
    readonly placeholder: _angular_core.InputSignal<string>;
    /** Disable the cascader. */
    readonly disabled: _angular_core.InputSignalWithTransform<boolean, any>;
    /** Control size — shares the `--wr-control-*` contract. @default 'md' */
    readonly size: _angular_core.InputSignal<WrCascaderSize>;
    /** Show a clear-all (×) button on the trigger when a path is selected. @default true */
    readonly clearable: _angular_core.InputSignalWithTransform<boolean, any>;
    /**
     * Allow selecting non-leaf (parent) nodes. When `false`, only leaves
     * (nodes without children) commit a selection. @default false
     */
    readonly changeOnSelect: _angular_core.InputSignalWithTransform<boolean, any>;
    /** Separator between labels in the trigger display. @default '/' */
    readonly separator: _angular_core.InputSignal<string>;
    /** Committed selection path (full T[] from root to leaf). @internal */
    protected readonly path: _angular_core.WritableSignal<readonly T[]>;
    /** Currently-expanded column path — drives which columns the panel shows. @internal */
    protected readonly activePath: _angular_core.WritableSignal<readonly T[]>;
    protected readonly open: _angular_core.WritableSignal<boolean>;
    /** Panel id used by the trigger's `aria-controls`. */
    protected readonly panelId: string;
    private readonly disabledFromCva;
    protected readonly isDisabled: _angular_core.Signal<boolean>;
    /**
     * Columns visible in the panel. Each column shows the children of the
     * preceding activePath entry. Column 0 = root options. The last
     * column is whatever the deepest active node's children resolve to —
     * we only render a column when there are children to show.
     */
    protected readonly columns: _angular_core.Signal<readonly (readonly WrCascaderOption<T>[])[]>;
    /** Label trail joined by `separator()` — what the trigger shows. */
    protected readonly displayLabel: _angular_core.Signal<string | null>;
    protected readonly hasSelection: _angular_core.Signal<boolean>;
    protected readonly classes: _angular_core.Signal<string>;
    protected readonly panelTpl: _angular_core.Signal<TemplateRef<any>>;
    private readonly host;
    private readonly overlay;
    private readonly vcr;
    private readonly scrollStrategies;
    private readonly destroyRef;
    private overlayRef;
    private onChange;
    protected onTouched: () => void;
    constructor();
    protected onTriggerClick(): void;
    protected onOptionClick(colIndex: number, opt: WrCascaderOption<T>, event: Event): void;
    protected clearSelection(event: Event): void;
    protected isActiveAt(colIndex: number, value: T): boolean;
    writeValue(value: unknown): void;
    registerOnChange(fn: (value: readonly T[]) => void): void;
    registerOnTouched(fn: () => void): void;
    setDisabledState(isDisabled: boolean): void;
    private openOverlay;
    private closeOverlay;
    static ɵfac: _angular_core.ɵɵFactoryDeclaration<WrCascader<any>, never>;
    static ɵcmp: _angular_core.ɵɵComponentDeclaration<WrCascader<any>, "wr-cascader", never, { "options": { "alias": "options"; "required": true; "isSignal": true; }; "placeholder": { "alias": "placeholder"; "required": false; "isSignal": true; }; "disabled": { "alias": "disabled"; "required": false; "isSignal": true; }; "size": { "alias": "size"; "required": false; "isSignal": true; }; "clearable": { "alias": "clearable"; "required": false; "isSignal": true; }; "changeOnSelect": { "alias": "changeOnSelect"; "required": false; "isSignal": true; }; "separator": { "alias": "separator"; "required": false; "isSignal": true; }; }, {}, never, never, true, never>;
}

export { WrCascader };
export type { WrCascaderOption, WrCascaderSize };