var test = require('tape')
var via = require('../')
var bufferEquals = require('buffer-equal')

test('via(func) - utf8', function (t) {
  var stream = via(function (data) {
    return data + 'yeah?'
  })

  stream.on('readable', function () {
    var chunk = this.read()
    if (chunk) {
      t.strictEqual(chunk, 'cliveyeah?')
      t.end()
    }
  })
  stream.setEncoding('utf8')
  stream.end('clive')
})

test('via.async(func) - utf8', function (t) {
  var stream = via.async(function (data, enc, done) {
    process.nextTick(function () {
      done(null, data + 'yeah?')
    })
  })

  stream.on('readable', function () {
    var chunk = this.read()
    if (chunk) {
      t.strictEqual(chunk, 'cliveyeah?')
      t.end()
    }
  })
  stream.setEncoding('utf8')
  stream.end('clive')
})

test('via(func) - buffer', function (t) {
  var stream = via(function (data) {
    return Buffer.concat([ data, Buffer([ 2 ]) ])
  })

  stream.on('readable', function () {
    var chunk = this.read()
    if (chunk) {
      t.ok(bufferEquals(chunk, Buffer([ 1, 2 ])))
      t.end()
    }
  })

  stream.end(Buffer([ 1 ]))
})

test('through function throws, via emits exception', function (t) {
  t.plan(1)
  var stream = via(function () {
    throw new Error('test')
  })
  stream.on('error', function (err) {
    t.strictEqual(err.message, 'test')
  })
  stream.end('data')
})

test('async through function returns err, via emits exception', function (t) {
  t.plan(1)
  var stream = via.async(function (chunk, enc, done) {
    done(new Error('test'))
  })
  stream.on('error', function (err) {
    t.strictEqual(err.message, 'test')
  })
  stream.end('data')
})

test('via: objectMode', function (t) {
  t.plan(1)

  var stream = via(function (object) {
    object.received = true
    return object
  }, { objectMode: true })

  stream.on('readable', function () {
    var chunk = this.read()
    if (chunk) {
      t.deepEquals(chunk, { received: true })
    }
  })

  stream.end({})
})

test('via: readableObjectMode', function (t) {
  var stream = via(
    function (buf) {
      t.strictEqual(buf.toString(), 'yeah')
      return {}
    },
    { readableObjectMode: true }
  )
  stream.end('yeah')
  t.end()
})