import { JSXInternal } from "./jsx";
import { ElementChildren, FunctionComponent } from "./shared";

import { subscribe } from "./observable";

declare namespace _h {
  function h(
    type: string,
    props:
      | (JSXInternal.HTMLAttributes | JSXInternal.SVGAttributes) &
        Record<string, unknown>
      | null,
    ...children: ElementChildren[]
  ): HTMLElement | SVGElement;
  function h(
    type: FunctionComponent,
    props:
      | (JSXInternal.HTMLAttributes | JSXInternal.SVGAttributes) &
        Record<string, unknown>
      | null,
    ...children: ElementChildren[]
  ): HTMLElement | SVGElement | DocumentFragment;
  function h(
    tag: ElementChildren[] | [],
    ...children: ElementChildren[]
  ): DocumentFragment;
  namespace h {
    export import JSX = JSXInternal;
  }
}

type Frag = { _startMark: Text }
type Value = Node | DocumentFragment | string | number

export interface HyperscriptApi {
  // Hyperscript
  h: typeof _h.h;

  // Internal API
  s: Boolean;
  insert<T>(el: Node, value: T, endMark?: Node, current?: T | Frag, startNode?: Node): T | Frag;
  property(el: Node, value: unknown, name: string, isAttr?: boolean, isCss?: boolean): void;
  add(parent: Node, value: Value | Value[], endMark?: Node): Node | Frag;
  rm(parent: Node, startNode: Node, endMark: Node): void;

  // Required from an observable implmentation
  subscribe: typeof subscribe;
}

export const api: HyperscriptApi;