import { CloseBehavior, MenuInstance, MenuInstanceOptions, PositionOptions, Selection } from "./MenuInstance"
import { MenuItem } from "./MenuItem"

export class Menu {
    private active?: MenuInstance

    async close(behavior = CloseBehavior.Immediate): Promise<void> {
        if (!this.active) return
        return this.active.close(behavior)
    }

    /**
     * Shows a menu.
     *
     * It'll resolve with the selected item, but not before all the animations
     * finish. Note that this may break the user interaction chain, so if you
     * want to execute code that needs to originate with a user interaction, use
     * the {@link MenuInstanceOptions#onSelection} callback instead of awaiting
     * the returned promise.
     */
    async show(
        items: MenuItem[],
        {
            className,
            location,
            within,
            isDarkMode,
            maxItemsPerMenu,
            enableTranslate,
            onSelection,
            expandRight,
        }: MenuInstanceOptions & PositionOptions
    ): Promise<Selection | null> {
        if (this.active) {
            if (this.active.isOpenWith(items)) {
                this.active.position({ location, within, expandRight })
                return this.active.wait()
            } else {
                await this.active.close(CloseBehavior.NoAnimation)
            }
        }

        const instance = new MenuInstance(items, { className, isDarkMode, maxItemsPerMenu, enableTranslate })
        this.active = instance
        const promise = instance.show({ location, within, expandRight }, onSelection)

        promise.finally(() => {
            if (this.active !== instance) return
            this.active = undefined
        })

        return promise
    }
}

/**
 * A single instance that can be used to avoid more than one menu showing on screen at once.
 */
export const menu = new Menu()