import { ElementVNode, Module, VNode } from '../'

export class ModuleCallbacks implements Module {
  private _modules: Array<Module>
  private _moduleCount: number

  constructor(modules: Array<Module>) {
    this._modules = modules
    this._moduleCount = modules.length
  }

  public createRemoveElementFn(element: Element) {
    let listeners = this._moduleCount + 1

    return function removeElement() {
      if (--listeners === 0) {
        const parent = element.parentNode as Node
        parent.removeChild(element)
      }
    }
  }

  // module hooks
  public pre(vNode: VNode) {
    const modules = this._modules
    const moduleCount = this._moduleCount

    for (let i = 0; i < moduleCount; ++i)
      modules[i].pre(vNode)
  }

  public post(vNode: ElementVNode) {
    const modules = this._modules
    const moduleCount = this._moduleCount

    for (let i = 0; i < moduleCount; ++i)
      modules[i].post(vNode)
  }

  public init(vNode: VNode) {
    const modules = this._modules
    const moduleCount = this._moduleCount

    for (let i = 0; i < moduleCount; ++i)
      modules[i].init(vNode)
  }

  public create(vNode: ElementVNode) {
    const modules = this._modules
    const moduleCount = this._moduleCount

    for (let i = 0; i < moduleCount; ++i)
      modules[i].create(vNode)
  }

  public update(formerVNode: ElementVNode, vNode: ElementVNode) {
    const modules = this._modules
    const moduleCount = this._moduleCount

    for (let i = 0; i < moduleCount; ++i)
      modules[i].update(formerVNode, vNode)
  }

  public remove(vNode: ElementVNode, removeElement: () => void) {
    const modules = this._modules
    const moduleCount = this._moduleCount

    for (let i = 0; i < moduleCount; ++i)
      modules[i].remove(vNode, removeElement)
  }

  public destroy(vNode: ElementVNode) {
    const modules = this._modules
    const moduleCount = this._moduleCount

    for (let i = 0; i < moduleCount; ++i)
      modules[i].destroy(vNode)
  }

  public prepatch(formerVNode: VNode, vNode: VNode) {
    const modules = this._modules
    const moduleCount = this._moduleCount

    for (let i = 0; i < moduleCount; ++i)
      modules[i].prepatch(formerVNode, vNode)
  }

  public postpatch(formerVNode: ElementVNode, vNode: ElementVNode) {
    const modules = this._modules
    const moduleCount = this._moduleCount

    for (let i = 0; i < moduleCount; ++i)
      modules[i].postpatch(formerVNode, vNode)
  }
}