import qs from 'qs'
import type { AjaxInstance, AnyObj, ProxyedAttrs } from './types'
import { callCancellerByCancelKey, hasCancelers } from './canceller'

/**
 * 标准化config配置，或根据配置项设置相关的参数
 * 该函数返回的配置对象，应该完全符合axios的配置规范
 * @param {*} config
 */
export function normalizeConfig<CusOpt extends object>(ctx: AjaxInstance<CusOpt>, config: any) {
  const {
    headers = {},
    sendFormData = false,
    data = undefined,
    params = {},
    baseUrl = '',
    baseURL = '',
    reUseDuration = 300,
    ...rest
  } = { ...ctx.$options, ...config }
  // 数据格式为FormData，修改content-type头，以及修改data格式
  const contentType = headers['content-type'] || headers['Content-Type'] || 'application/json'
  headers['content-type'] = sendFormData ? 'application/x-www-form-urlencoded' : contentType
  const sendData = sendFormData && typeof data === 'object' && data !== null ? qs.stringify(data) : data

  // baseUrl，支持两种写法，且用户配置的baseUrl优先级最高
  const bUrl = baseUrl || baseURL || ctx.$baseUrl

  if (typeof reUseDuration !== 'number' || Number.isNaN(reUseDuration)) {
    throw new Error('ajax配置reUseDuration必须是数字')
  }

  return {
    headers,
    params,
    data: sendData,
    baseURL: bUrl,
    reUseDuration,
    ...rest,
  }
}

export function addInstanceExtendMethod(ctx: any) {
  const extend = (source: AnyObj) => {
    Object.keys(source).forEach((key) => {
      ctx[key] = source[key]
    })
  }
  ctx.extend = extend
}

export function proxyAxiosInstanceAttrs<S extends { [K in ProxyedAttrs]: any }>(target: AnyObj, source: S): void {
  const attrs: ProxyedAttrs[] = ['request', 'interceptors', 'defaults']
  // const methods: ProxyedAttrs[] = ['request', 'get', 'post', 'delete', 'head', 'options', 'put', 'patch', 'interceptors'];

  attrs.forEach((method) => {
    Object.defineProperty(target, method, {
      value: source[method],
      writable: false,
    })
  })
}

export function proxyAjaxCanceler(ctx: AjaxInstance) {
  ctx.canceller = new Proxy(
    {},
    {
      get(_target, prop: string) {
        if (!hasCancelers(prop)) {
          return () => {
            const str = `ajax.canceller对象上不存在名为${prop}的函数！`
            console.warn(str)
            return str
          }
        }
        return () => {
          callCancellerByCancelKey(prop)
        }
      },
    }
  )
}