import { LitElement } from "lit";
export type SkyButtonVariant = "solid" | "faded" | "bordered" | "transparent" | "flat" | "ghost" | "relief" | "gradient" | "shadow" | "link";
export type SkyButtonType = "button" | "submit" | "reset";
export type SkyButtonAnimation = "auto" | "none" | "lift" | "push" | "scale" | "rotate" | "custom";
/**
 * @element sky-button
 *
 * @summary Styled button supporting variants, icons, loading state, ripple feedback, and form-associated behavior.
 *
 * @status stable
 * @since 1.0.0
 *
 * @documentation https://sky-ui.com/components/button
 * @dependency sky-icon
 *
 * @slot - Default slot for the button label (replaces `label` property if used).
 *
 * @csspart button - The native `<button>` element.
 * @csspart icon - The optional left/right icons.
 * @csspart loading-overlay - Overlay displayed when loading.
 * @csspart spinner - Spinner displayed when loading.
 *
 * @property {SkyButtonVariant} variant - Visual variant of the button. Use `"link"` for text-only control with underline on hover. Default: `"solid"`.
 * @property {string} color - Base color token or custom CSS color. Default: `"primary"`.
 * @property {SkyButtonType} type - Button type attribute. Default: `"button"`.
 * @property {string} form - Associated form ID for custom submit handling.
 * @property {string} size - Preset size token (`xs…xl`) or CSS size (e.g., `"15px"`, `"1rem"`). Default: `"md"`.
 * @property {string} radius - Preset radius token (`none…full`) or CSS radius (e.g., `"12px"`). Default: `"md"`.
 * @property {string} label - Text label for the button. Ignored if default slot is used. Default: `"Button"`.
 * @property {boolean} disabled - Whether the button is disabled. Default: `false`.
 * @property {boolean} loading - Shows a loading overlay when true. Default: `false`.
 * @property {string} iconL - Optional left-side icon (Iconify name). Default: `""`.
 * @property {string} iconR - Optional right-side icon (Iconify name). Default: `""`.
 * @property {boolean} iconOnly - Square padding for icon-only buttons; hides label text. Default: `false`.
 * @property {string} colors - Comma-separated color stops for gradient variant. Default: `""`.
 * @property {SkyButtonAnimation} animation - Transform animation style. Default: `"auto"`.
 * @property {string} preset - Named prop preset from nearest `sky-config-provider`. Default: `""`.
 * @method focusButton Focuses the internal native button.
 * @method clickButton Triggers a click on the internal native button when enabled.
 *
 * @example
 * ```html
 * <sky-button variant="gradient" colors="linear@90deg: primary, secondary" iconl="ion:add" label="Create"></sky-button>
 * <sky-button preset="cancel" label="Cancel"></sky-button>
 * ```
 * ```vue
 * <template>
 *   <sky-button variant="gradient" colors="linear@90deg: primary, secondary" iconl="ion:add" label="Create"></sky-button>
 *   <sky-button preset="cancel" label="Cancel"></sky-button>
 * </template>
 * ```
 * ```jsx
 * export default function Demo() {
 *   return (
 *     <>
 *       <sky-button variant="gradient" colors="linear@90deg: primary, secondary" iconl="ion:add" label="Create"></sky-button>
 *       <sky-button preset="cancel" label="Cancel"></sky-button>
 *     </>
 *   );
 * }
 * ```
 */
export declare class SkyButton extends LitElement {
    static dependencies: Record<string, CustomElementConstructor>;
    static formAssociated: boolean;
    private internals;
    /** Visual variant of the button. */
    variant: SkyButtonVariant;
    /** Accepts preset tokens OR any valid CSS color (e.g., #0af, rgb(), var(--x)). */
    color: string;
    /** Button type attribute. */
    type: SkyButtonType;
    /** Associated form ID for custom form handling. */
    form: string;
    /** Preset tokens (`xs…xl`) OR CSS size like `"15px"`. */
    size: string;
    /** Preset tokens (`none…full`) OR any CSS border radius. */
    radius: string;
    /** Text label for the button. */
    label: string;
    /** Disables the button. */
    disabled: boolean;
    /** Shows a loading spinner overlay. */
    loading: boolean;
    /** Left-side icon (Iconify icon name). */
    iconL: string;
    /** Right-side icon (Iconify icon name). */
    iconR: string;
    /** Square padding and compact layout when the button shows only an icon. */
    iconOnly: boolean;
    /** Colors for gradient variant. */
    colors: string;
    /** Animation style for hover/active transforms. */
    animation: SkyButtonAnimation;
    /** Named prop preset from nearest `sky-config-provider`. */
    preset: string;
    /** @internal Set by `sky-button-group` to flatten grouped button visuals. */
    inGroup: boolean;
    private _hasMeaningfulSlot;
    /** Inline CSS variable cache. */
    private _styleVars;
    private _presets;
    private _lastPresetRevision;
    /** Set when presets change so `update()` rebuilds CSS vars after hostUpdate. */
    private _styleDirty;
    static styles: import("lit").CSSResult[];
    constructor();
    private _slotHasMeaningfulContent;
    private _onSlotChange;
    /** Uses vertical padding for equal sides (icon-only square control). */
    private _toSquarePadding;
    private _resolveSize;
    /** Theme tokens like `var(--sky-border-primary)` are full border shorthands, not colors. */
    private _isThemeBorderShorthand;
    /** Extracts the color token from a `Npx solid …` border shorthand. */
    private _borderColorFromShorthand;
    /**
     * Lit order: `willUpdate` → controllers `hostUpdate` (presets) → `update`/render.
     * Style vars must be built in `update()` so they see preset-applied props.
     * Building in `willUpdate` left render with `{}` after PresetController cleared/wrote props.
     */
    protected update(changedProperties: Map<string, unknown>): void;
    private _rebuildStyleVars;
    /**
     * Focuses the internal native button.
     *
     * @returns {void}
     */
    focusButton(): void;
    /**
     * Triggers a click on the internal native button when enabled.
     *
     * @returns {void}
     */
    clickButton(): void;
    private _createRipple;
    formDisabledCallback(disabled: boolean): void;
    get formOwner(): HTMLFormElement | null;
    private _handleClick;
    private _iconOnlyName;
    render(): import("lit-html").TemplateResult<1>;
}