// It's just simplified Qs, only supports primitive value except Symbol

function isPlainObject (o) { return Object.prototype.toString.call(o) === '[object Object]' }

function isString (o) { return Object.prototype.toString.call(o) === '[object String]' }

export function stringify (query, { addQueryPrefix = false } = {}) {
  if (!isPlainObject(query)) {
    return ''
  }

  return Object.keys(query)
    .reduce(
      (querystring, property) => {
        if (query[property] === void 0) { /* skip undefined */
          return querystring
        }

        return querystring + '&' + encodeURIComponent(property) + '=' + encodeURIComponent(query[property])
      },
      ''
    )
    .replace(/^&/, addQueryPrefix ? '?' : '')
}

const BOOLEAN_STRINGS = [ 'false', 'true' ]
export function parse (querystring, { ignoreQueryPrefix = false } = {}) {
  if (!isString(querystring)) {
    return {}
  }

  return querystring
    .replace(/^\?/, ignoreQueryPrefix ? '' : '$&')
    .split('&')
    .reduce(
      (query, string) => {
        const [ property, value ] = string
          .split('=')
          .map((string = '') => decodeURIComponent(string))

        if (!!~BOOLEAN_STRINGS.indexOf(value)) {
          query[property] = !!BOOLEAN_STRINGS.indexOf(value)
        } else {
          query[property] = value
        }

        return query
      },
      {}
    )
}

export default {
  stringify,
  parse
}