// Copyright 2015 Joyent, Inc.

var assert = require('assert')
var util = require('util')

var isDN = require('./dn').DN.isDN
var isAttribute = require('./attribute').isAttribute

/// --- Helpers

// Copied from mcavage/node-assert-plus
function _assert (arg, type, name) {
  name = name || type
  throw new assert.AssertionError({
    message: util.format('%s (%s) required', name, type),
    actual: typeof (arg),
    expected: type,
    operator: '===',
    stackStartFunction: _assert.caller
  })
}

/// --- API

function stringDN (input, name) {
  if (isDN(input) || typeof (input) === 'string') { return }
  _assert(input, 'DN or string', name)
}

function optionalStringDN (input, name) {
  if (input === undefined || isDN(input) || typeof (input) === 'string') { return }
  _assert(input, 'DN or string', name)
}

function optionalDN (input, name) {
  if (input !== undefined && !isDN(input)) { _assert(input, 'DN', name) }
}

function optionalArrayOfAttribute (input, name) {
  if (input === undefined) { return }
  if (!Array.isArray(input) ||
      input.some(function (v) { return !isAttribute(v) })) {
    _assert(input, 'array of Attribute', name)
  }
}

/// --- Exports

module.exports = {
  stringDN: stringDN,
  optionalStringDN: optionalStringDN,
  optionalDN: optionalDN,
  optionalArrayOfAttribute: optionalArrayOfAttribute
}