import _WidgetBase = require("./_WidgetBase");
import { PlacePosition, PlaceLocation } from "./place";

interface PopupOpenArgs {
    /**
     * widget to display
     */
    popup?: _WidgetBase;

    /**
     * the button etc. that is displaying this popup
     */
    parent?: _WidgetBase;

    /**
     * DOM node (typically a button); place popup relative to this node.  (Specify this *or* "x" and "y" parameters.)
     */
    around?: HTMLElement;

    /**
     * Absolute horizontal position (in pixels) to place node at.  (Specify this *or* "around" parameter.)
     */
    x?: number;

    /**
     * Absolute vertical position (in pixels) to place node at.  (Specify this *or* "around" parameter.)
     */
    y?: number;

    /**
     * When the around parameter is specified, orient should be a list of positions to try
     */
    orient?: string | string[] | { BL?: string; TR?: string; TL?: string; BR?: string; };

    /**
     * callback when user has canceled the popup by:
     *
     * 1. hitting ESC or
     * 2. by using the popup widget's proprietary cancel mechanism (like a cancel button in a dialog);
     *    i.e. whenever popupWidget.onCancel() is called, args.onCancel is called
     */
    onCancel?: () => void;

    /**
     * callback whenever this popup is closed
     */
    onClose?: () => void;

    /**
     * callback when user "executed" on the popup/sub-popup by selecting a menu choice, etc. (top menu only)
     */
    onExecute?: () => void;

    /**
     * adding a buffer around the opening position. This is only useful when around is not set.
     */
    padding?: PlacePosition;

    /**
     * The max height for the popup.  Any popup taller than this will have scrollbars.
     * Set to Infinity for no max height.  Default is to limit height to available space in viewport,
     * above or below the aroundNode or specified x/y position.
     */
    maxHeight?: number;
}

interface PopupManager {
    /**
     * Stack of currently popped up widgets.
     * (someone opened _stack[0], and then it opened _stack[1], etc.)
     */
    _stack: _WidgetBase[];

    /**
     * Z-index of the first popup.   (If first popup opens other
     * popups they get a higher z-index.)
     */
    _beginZIndex: number;

    _idGen: number;

    /**
     * If screen has been scrolled, reposition all the popups in the stack.
     * Then set timer to check again later.
     */
    _repositionAll(): void;

    /**
     * Initialization for widgets that will be used as popups.
     * Puts widget inside a wrapper DIV (if not already in one),
     * and returns pointer to that wrapper DIV.
     */
    _createWrapper(widget: _WidgetBase): HTMLDivElement;

    /**
     * Moves the popup widget off-screen.
     * Do not use this method to hide popups when not in use, because
     * that will create an accessibility issue: the offscreen popup is
     * still in the tabbing order.
     */
    moveOffScreen(widget: _WidgetBase): HTMLDivElement;

    /**
     * Hide this popup widget (until it is ready to be shown).
     * Initialization for widgets that will be used as popups
     *
     * Also puts widget inside a wrapper DIV (if not already in one)
     *
     * If popup widget needs to layout it should
     * do so when it is made visible, and popup._onShow() is called.
     */
    hide(widget: _WidgetBase): void;

    /**
     * Compute the closest ancestor popup that's *not* a child of another popup.
     * Ex: For a TooltipDialog with a button that spawns a tree of menus, find the popup of the button.
     */
    getTopPopup(): _WidgetBase;

    /**
     * Popup the widget at the specified position
     */
    open(args: PopupOpenArgs): PlaceLocation;

    /**
     * Close specified popup and any popups that it parented.
     * If no popup is specified, closes all popups.
     */
    close(popup?: _WidgetBase): void;
}