const Toa = require('toa')
const toaCORS = require('toa-cors')

const app = new Toa()
app.use(toaCORS({
  credentials: true,
  allowOrigins: ['*']
}))
app.use(function () {
  this.body = 'hello'
})
app.listen(3000)

app.use(toaCORS(options))

const defaultOptions = {
  // allowOrigins defines the origins which will be allowed to access
  // the resource. Default value is:
  allowOrigins: ['*'],
  // allowMethods defines the methods which will be allowed to access
  // the resource. It is used in handling the preflighted requests.
  // Default value is:
  allowMethods: ['GET', 'HEAD', 'PUT', 'POST', 'DELETE', 'PATCH'],
  // allowHeaders defines the headers which will be allowed in the actual
  // request. It is used in handling the preflighted requests.
  allowHeaders: [],
  // exposeHeaders defines the allowed headers that client could send when
  // accessing the resource.
  exposeHeaders: [],
  // maxAge defines the max age that the preflighted requests can be cached, seconds.
  maxAge: 0,
  // credentials defines whether or not the response to the request can be exposed.
  credentials: false,
  // allowOriginsValidator validates the request Origin by validator
  // function. The validator function accpects the origin and should returns the
  // Access-Control-Allow-Origin value. If the validator is set, then
  // allowMethods will be ignored.
  allowOriginsValidator: null
}

if (opts.allowOriginsValidator == null) {
  opts.allowOriginsValidator = (origin) => {
    for (let key of Object.keys(opts.allowOrigins)) {
      if (opts.allowOrigins[key] === origin || opts.allowOrigins[key] === '*') {
        return origin
      }
    }
    return ''
  }
}