import type { RouteLocationRaw, RouteRecordRaw, RouteRecordName } from 'vue-router';
import type { Component } from '@vue/runtime-core';

/* This is some sort of PEP440 subset */
type Join<T extends unknown[], D extends string> = T extends []
  ? ''
  : T extends [string | number | boolean | bigint]
  ? `${T[0]}`
  : T extends [string | number | boolean | bigint, ...infer U]
  ? `${T[0]}${D}${Join<U, D>}`
  : string;
type BaseVersion = Join<[number, number], '.'> | Join<[number, number, number], '.'>;
type PreRelease = Join<[['a' | 'b' | 'rc'], number], '.'>;
type PRVersion = BaseVersion | `${BaseVersion}${PreRelease}`;
/** A PEP440 subset used to describe backend module versions */
export type PEP440Version = PRVersion | `${PRVersion}.dev${number}`;

export namespace FG_Plugin {
  /**
   * Interface defining a Flaschengeist plugin
   */
  export interface Plugin {
    /** Unique identifier for this plugin, we recommend using a FQN like com.example.my_plugin */
    id: string;
    /** Arbitrary name of the plugin used inside admin view etc */
    name: string;
    /** Version of this plugin, used for dependencies. MUST be semver parsable */
    version: string;
    /** Widgets provided by this plugin */
    widgets: Widget[];
    /** Backend modules needed for this plugin to work correctly */
    requiredModules: [string, PEP440Version?][];
    /** Menu entries for authenticated users */
    innerRoutes?: MenuRoute[];
    /** Public menu entries (without authentification) */
    outerRoutes?: MenuRoute[];
    /** Routes without menu links, for internal usage */
    internalRoutes?: NamedRouteRecordRaw[];
    /** Handle notifications, defaults to boot/plugins.ts:translateNotification() */
    notification?(msg: FG.Notification): FG_Plugin.Notification;
  }

  /**
   * Defines the loaded state of the Flaschengeist
   */
  export interface Flaschengeist {
    /** All loaded plugins */
    plugins: LoadedPlugin[];
    /** All routes, combined from all plugins */
    routes: RouteRecordRaw[];
    /** All menu entries */
    menuLinks: MenuLink[];
    /** All inner shortcuts */
    shortcuts: Shortcut[];
    /** All outer shortcuts */
    outerShortcuts: Shortcut[];
    /** All widgets */
    widgets: Widget[];
  }

  /**
   * Interface for a frontend notification
   */
  export interface Notification extends FG.Notification {
    /** If set a button for accepting will be shown, this function will get called before deleting the notification */
    accept?(): Promise<void>;
    /** If set this function is called before the notification gets deleted */
    reject?(): Promise<void>;
    /** If set the notification text is interpreted as a link to this location */
    link?: RouteLocationRaw;
    /** If set this icon is used */
    icon?: string;
  }

  /**
   * Loaded Flaschengeist plugin
   */
  interface LoadedPlugin {
    name: string;
    version: string;
    notification(msg: FG.Notification): FG_Plugin.Notification;
  }

  /**
   * Defines a shortcut link
   */
  export interface Shortcut {
    link: RouteRecordName;
    icon: string;
    permissions?: string[];
  }

  type NamedRouteRecordRaw = RouteRecordRaw & {
    name: RouteRecordName;
  };

  /**
   * Defines a main menu entry along with the route
   * Used when defining a plugin
   */
  export interface MenuRoute extends MenuEntry {
    route: NamedRouteRecordRaw;
    shortcut?: boolean;
    children?: this[];
  }

  /**
   * Defines a menu entry in the main menu
   */
  export interface MenuLink extends MenuEntry {
    /** Name of the target route */
    link: RouteRecordName;
    /**
     * Order inside the menu, higher numbers come ahead of lower numbers 
     * @todo: Promote to required with first beta
     */
    order?: number;
  }

  /**
   * Base interface for internal use
   */
  interface MenuEntry {
    title: string | (() => string);
    icon: string;
    permissions?: string[];
    children?: this[];
  }

  /**
   * Widget object for the dashboard
   */
  export interface Widget {
    name: string;
    /**
     * @deprecated Deprecated in favor of order
     * @todo Remove with beta 1
     */
    priority?: number;
    /**
     * Default order on the dashboard, higher numbers come ahead of lower numbers 
     * @todo Promote to required if priority is removed
    */
    order?: number;
    permissions: FG.Permission[];
    widget: Component;
  }
}