/**
 * Pure task-pane motion math — snappy enter/exit (faster than toasts).
 *
 * Open:  slide in (~120ms ease-out)
 * Close: slide out (~100ms ease-in), then unmount
 */
/** Slide-in duration — a bit snappier than toast (200ms). */
export declare const PLAN_PANE_ENTER_MS = 120;
/** Slide-out duration — slightly faster than enter so hide feels instant. */
export declare const PLAN_PANE_EXIT_MS = 100;
export type PaneAnimPhase = "enter" | "open" | "exit" | "closed";
export interface PaneAnimState {
    readonly phase: PaneAnimPhase;
    /** 0 = fully hidden, 1 = fully shown. */
    readonly progress: number;
    /** Keep the pane in the tree during enter/open/exit. */
    readonly mounted: boolean;
}
/**
 * Progress for a known phase + age within that phase.
 */
export declare function paneProgress(phase: PaneAnimPhase, ageMs: number, enterMs?: number, exitMs?: number): number;
export declare function paneMounted(phase: PaneAnimPhase): boolean;
/**
 * Overlay placement: slide from above the viewport to restTop.
 * @param progress 0..1 visibility
 * @param restTop resting top row when fully open
 * @param paneHeight box height (for off-screen start)
 */
export declare function paneSlideTop(progress: number, restTop: number, paneHeight: number): number;
/**
 * Split placement: grow/shrink width with progress.
 */
export declare function paneSlideWidth(progress: number, fullWidth: number): number;
/**
 * Whether the enter/exit phase has finished and should advance.
 */
export declare function panePhaseComplete(phase: PaneAnimPhase, ageMs: number, enterMs?: number, exitMs?: number): PaneAnimPhase | null;