import { EventEmitter, OnChanges, OnDestroy, SimpleChanges } from '@angular/core';
import { CardComponent } from './card.component';
import * as i0 from "@angular/core";
/**
 * Top row of a `riv-card`: heading text plus optional adornments.
 *
 * Three projection slots, all optional:
 * - `[leading]` — icon, avatar, or status dot shown before the heading
 * - default — laid out on the heading's baseline, so status badges sit beside
 *   the title and wrap below it when space runs out. Also takes a whole custom
 *   title (an inline rename field, say) when `heading` is left unset;
 *   `subheading` still renders below either way.
 * - `[actions]` — trailing controls such as `riv-menu`
 *
 * ```html
 * <riv-card-header [heading]="'Commercial 2025'" [subheading]="'Aetna'">
 *   <riv-icon leading [name]="'FileText'"></riv-icon>
 *   <riv-badge [size]="'small'" [variant]="'categorical-8'">Draft</riv-badge>
 *   <riv-menu actions>...</riv-menu>
 * </riv-card-header>
 * ```
 *
 * `headingLevel` renders a real `h1`–`h6` so the card fits the page's heading
 * outline; pick the level that follows the surrounding content rather than the
 * one that looks right, since size comes from the design tokens either way.
 *
 * The heading font and colour can be overridden per-instance with the
 * `--card-heading-font` and `--card-heading-color` custom properties.
 *
 * ## Expanding and collapsing
 *
 * `expandable` turns the header into the toggle for the card's body: it renders
 * a chevron and covers the row with a real `<button>` carrying `aria-expanded`
 * and `aria-controls`, so the pattern is keyboard operable and announces its
 * state. Controls in `[actions]` sit above that button and stay independently
 * clickable, so a menu beside the toggle needs no `stopPropagation`.
 *
 * The header holds no state of its own — bind `expanded` and act on
 * `expandedChange`, or use `[(expanded)]`:
 *
 * ```html
 * <riv-card>
 *   <riv-card-header
 *     [heading]="'Patient info'"
 *     [expandable]="true"
 *     [(expanded)]="open"
 *   ></riv-card-header>
 *   <riv-card-content *ngIf="open">...</riv-card-content>
 * </riv-card>
 * ```
 *
 * The toggle is named by the header's title, so an expandable header needs a
 * `heading` or a projected title.
 */
export declare class CardHeaderComponent implements OnChanges, OnDestroy {
    private readonly card;
    constructor(card: CardComponent | null);
    /**
     * Identifies the title for a clickable `riv-card`, which names its click
     * target from the title rather than from the card's whole text.
     */
    readonly titleId: string;
    /**
     * Names the body the toggle controls. Handed to the enclosing card, which
     * relays it to the projected `riv-card-content`.
     */
    readonly regionId: string;
    /** Heading text. Omit when projecting custom heading markup instead. */
    heading?: string;
    /** Supporting text rendered below the heading. */
    subheading?: string;
    /** Heading element rendered for `heading`, for document outline purposes. */
    headingLevel: CardHeaderComponent.HeadingLevel;
    /** `filled` gives the header its own background, separating it from the body. */
    variant: CardHeaderComponent.Variant;
    padding: CardComponent.Padding;
    /** Draws a separator below the header. Implied by the `filled` variant. */
    divider: boolean;
    /** Cross-axis alignment of the leading slot, heading block, and actions. */
    align: CardHeaderComponent.Align;
    /**
     * Truncates the heading to this many lines with an ellipsis. Leave unset to
     * let the heading wrap freely.
     */
    clamp?: number;
    /** Turns the header row into the toggle for the card's body. */
    expandable: boolean;
    /** Whether the body is currently open. The consumer owns this state. */
    expanded: boolean;
    /** Side of the header the chevron sits on. */
    togglePosition: CardHeaderComponent.TogglePosition;
    /**
     * Blocks the toggle, for a section that is not yet available to open. Set it
     * alongside a disabled `riv-card`, whose own `disabled` mutes the surface but
     * does not reach the header's controls.
     */
    disabled: boolean;
    /** Emitted with the state the consumer is being asked to move to. */
    expandedChange: EventEmitter<boolean>;
    /**
     * Offers the heading to an enclosing card as the name for its click target,
     * and the toggle's region so a projected `riv-card-content` can wear it. Only
     * a text heading is offered: projected titles can be anything, so those cards
     * fall back to naming against their whole content.
     */
    ngOnChanges(changes: SimpleChanges): void;
    /** Withdraws the offer, so the card stops naming itself against this header. */
    ngOnDestroy(): void;
    /**
     * Asks for the opposite state rather than taking it, which keeps the header
     * free of state that could drift from the consumer's.
     */
    protected toggle(): void;
    get classes(): string;
    /**
     * Line clamping is applied inline so the line count stays a plain input
     * rather than a fixed set of CSS classes.
     */
    get clampStyle(): Record<string, string>;
    static ɵfac: i0.ɵɵFactoryDeclaration<CardHeaderComponent, [{ optional: true; }]>;
    static ɵcmp: i0.ɵɵComponentDeclaration<CardHeaderComponent, "riv-card-header", never, { "heading": "heading"; "subheading": "subheading"; "headingLevel": "headingLevel"; "variant": "variant"; "padding": "padding"; "divider": "divider"; "align": "align"; "clamp": "clamp"; "expandable": "expandable"; "expanded": "expanded"; "togglePosition": "togglePosition"; "disabled": "disabled"; }, { "expandedChange": "expandedChange"; }, never, ["[leading]", "*", "[actions]"], false, never>;
}
export declare namespace CardHeaderComponent {
    const Variants: readonly ["plain", "filled"];
    type Variant = (typeof Variants)[number];
    const HeadingLevels: readonly [1, 2, 3, 4, 5, 6];
    type HeadingLevel = (typeof HeadingLevels)[number];
    const Aligns: readonly ["start", "center"];
    type Align = (typeof Aligns)[number];
    const TogglePositions: readonly ["leading", "trailing"];
    type TogglePosition = (typeof TogglePositions)[number];
}