@newy/define

export class VNode {
  public children?: any[]
  public tag?: string
  constructor(
    public template: string | TemplateStringsArray,
    public propList: any[]
  ) {}
}

export function h(template: TemplateStringsArray | string, ...propList: any[]) {
  if (!isTemplateStringsArray(template) && !is(template, 'string'))
    throw new Error('template should be a string or a TemplateStringsArray')

  const vnode = new VNode(template, propList)
  const res = Object.setPrototypeOf(
    Object.assign(
      (...children: any[]) => {
        if (children.length) vnode.children = children
        if (res.tag) vnode.tag = res.tag
        return vnode
      },
      vnode,
      { [Symbol.toStringTag]: VNode.name }
    ),
    VNode.prototype
  ) as ((...children: any[]) => VNode) & VNode
  return res
}

export function define<T extends (...args: any[]) => any>(tag: string, fn: T, ...options: any[]) {
  return (template: TemplateStringsArray | string, ...propList: Parameters<T>) => {
    const res = h(template, ...propList)
    res.tag = tag
    return res
  }
}