import { Router } from 'express'

import Route from './models/Route'
import { Methods } from './constants/methods'

export default (middleware, options) => (...routes) => {
  let expressRouter = Router(options)

  if (middleware) {
    expressRouter.use('/', middleware)
  }

  const routerMethodsMap = {
    [Methods.GET]: expressRouter.get.bind(expressRouter),
    [Methods.POST]: expressRouter.post.bind(expressRouter),
    [Methods.PUT]: expressRouter.put.bind(expressRouter),
    [Methods.DELETE]: expressRouter.delete.bind(expressRouter),
  }

  routes.forEach(route => {
    routerMethodsMap[route.method](route.path, ...route.middleware, route.handler)

    route.subroutes.forEach(subroute => {
      routerMethodsMap[subroute.method](subroute.path, ...subroute.middleware, subroute.handler)
    })
  })

  return expressRouter
}

const route = (path, handler, method, subroutes, ...middleware) => new Route({ path, handler, method, middleware, subroutes })

export const get = (...middleware) => (path, handler, ...subroutes) => route(path, handler, Methods.GET, subroutes, middleware)

export const post = (...middleware) => (path, handler, ...subroutes) => route(path, handler, Methods.POST, subroutes, middleware)

export const put = (...middleware) => (path, handler, ...subroutes) => route(path, handler, Methods.PUT, subroutes, middleware)

export const delet = (...middleware) => (path, handler, ...subroutes) => route(path, handler, Methods.DELETE, subroutes, middleware)


//constants/methods.js
const Methods = {
  GET: 'GET',
  POST: 'POST',
  PUT: 'PUT',
  DELETE: 'DELETE',
}

export { Methods }

models/Route.js
export default class Route {
  constructor({ path, handler, method, middleware, subroutes }) {
    this._path = path
    if (typeof handler !== 'function') {
      throw new Error('Route handler must be a function!')
    }
    this._handler = handler
    this._method = method
    this._middleware = middleware
    const subroutesWithMappedPath = subroutes.map(subroute => {
      subroute.path = `${path}${subroute.path}`
      return subroute
    })
    this._subroutes = subroutesWithMappedPath
  }

  get path() {
    return this._path
  }

  set path(path) {
    this._path = path
  }

  get handler() {
    return this._handler
  }

  get method() {
    return this._method
  }

  get middleware() {
    return this._middleware
  }

  get subroutes() {
    return this._subroutes
  }
}