import buffers from './testing/test-buffers'
import BufferList from './testing/buffer-list'
import { PgPacketStream } from './'
import assert from 'assert'
import { Readable } from 'stream'

var authOkBuffer = buffers.authenticationOk()
var paramStatusBuffer = buffers.parameterStatus('client_encoding', 'UTF8')
var readyForQueryBuffer = buffers.readyForQuery()
var backendKeyDataBuffer = buffers.backendKeyData(1, 2)
var commandCompleteBuffer = buffers.commandComplete('SELECT 3')
var parseCompleteBuffer = buffers.parseComplete()
var bindCompleteBuffer = buffers.bindComplete()
var portalSuspendedBuffer = buffers.portalSuspended()

var addRow = function (bufferList: BufferList, name: string, offset: number) {
  return bufferList.addCString(name) // field name
    .addInt32(offset++) // table id
    .addInt16(offset++) // attribute of column number
    .addInt32(offset++) // objectId of field's data type
    .addInt16(offset++) // datatype size
    .addInt32(offset++) // type modifier
    .addInt16(0) // format code, 0 => text
}

var row1 = {
  name: 'id',
  tableID: 1,
  attributeNumber: 2,
  dataTypeID: 3,
  dataTypeSize: 4,
  typeModifier: 5,
  formatCode: 0
}
var oneRowDescBuff = buffers.rowDescription([row1])
row1.name = 'bang'

var twoRowBuf = buffers.rowDescription([row1, {
  name: 'whoah',
  tableID: 10,
  attributeNumber: 11,
  dataTypeID: 12,
  dataTypeSize: 13,
  typeModifier: 14,
  formatCode: 0
}])

var emptyRowFieldBuf = new BufferList()
  .addInt16(0)
  .join(true, 'D')

var emptyRowFieldBuf = buffers.dataRow([])

var oneFieldBuf = new BufferList()
  .addInt16(1) // number of fields
  .addInt32(5) // length of bytes of fields
  .addCString('test')
  .join(true, 'D')

var oneFieldBuf = buffers.dataRow(['test'])

var expectedAuthenticationOkayMessage = {
  name: 'authenticationOk',
  length: 8
}

var expectedParameterStatusMessage = {
  name: 'parameterStatus',
  parameterName: 'client_encoding',
  parameterValue: 'UTF8',
  length: 25
}

var expectedBackendKeyDataMessage = {
  name: 'backendKeyData',
  processID: 1,
  secretKey: 2
}

var expectedReadyForQueryMessage = {
  name: 'readyForQuery',
  length: 5,
  status: 'I'
}

var expectedCommandCompleteMessage = {
  name: 'commandComplete',
  length: 13,
  text: 'SELECT 3'
}
var emptyRowDescriptionBuffer = new BufferList()
  .addInt16(0) // number of fields
  .join(true, 'T')

var expectedEmptyRowDescriptionMessage = {
  name: 'rowDescription',
  length: 6,
  fieldCount: 0,
  fields: [],
}
var expectedOneRowMessage = {
  name: 'rowDescription',
  length: 27,
  fieldCount: 1,
  fields: [{
    name: 'id',
    tableID: 1,
    columnID: 2,
    dataTypeID: 3,
    dataTypeSize: 4,
    dataTypeModifier: 5,
    format: 'text'
  }]
}

var expectedTwoRowMessage = {
  name: 'rowDescription',
  length: 53,
  fieldCount: 2,
  fields: [{
    name: 'bang',
    tableID: 1,
    columnID: 2,
    dataTypeID: 3,
    dataTypeSize: 4,
    dataTypeModifier: 5,
    format: 'text'
  },
  {
    name: 'whoah',
    tableID: 10,
    columnID: 11,
    dataTypeID: 12,
    dataTypeSize: 13,
    dataTypeModifier: 14,
    format: 'text'
  }]
}

const concat = (stream: Readable): Promise<any[]> => {
  return new Promise((resolve) => {
    const results: any[] = []
    stream.on('data', item => results.push(item))
    stream.on('end', () => resolve(results))
  })
}

var testForMessage = function (buffer: Buffer, expectedMessage: any) {
  it('recieves and parses ' + expectedMessage.name, async () => {
    const parser = new PgPacketStream();
    parser.write(buffer);
    parser.end();
    const [lastMessage] = await concat(parser);

    for (const key in expectedMessage) {
      assert.deepEqual(lastMessage[key], expectedMessage[key])
    }

  })
}

var plainPasswordBuffer = buffers.authenticationCleartextPassword()
var md5PasswordBuffer = buffers.authenticationMD5Password()
var SASLBuffer = buffers.authenticationSASL()
var SASLContinueBuffer = buffers.authenticationSASLContinue()
var SASLFinalBuffer = buffers.authenticationSASLFinal()

var expectedPlainPasswordMessage = {
  name: 'authenticationCleartextPassword'
}

var expectedMD5PasswordMessage = {
  name: 'authenticationMD5Password',
  salt: Buffer.from([1, 2, 3, 4])
}

var expectedSASLMessage = {
  name: 'authenticationSASL',
  mechanisms: ['SCRAM-SHA-256']
}

var expectedSASLContinueMessage = {
  name: 'authenticationSASLContinue',
  data: 'data',
}

var expectedSASLFinalMessage = {
  name: 'authenticationSASLFinal',
  data: 'data',
}

var notificationResponseBuffer = buffers.notification(4, 'hi', 'boom')
var expectedNotificationResponseMessage = {
  name: 'notification',
  processId: 4,
  channel: 'hi',
  payload: 'boom'
}

describe('PgPacketStream', function () {
  testForMessage(authOkBuffer, expectedAuthenticationOkayMessage)
  testForMessage(plainPasswordBuffer, expectedPlainPasswordMessage)
  testForMessage(md5PasswordBuffer, expectedMD5PasswordMessage)
  testForMessage(SASLBuffer, expectedSASLMessage)
  testForMessage(SASLContinueBuffer, expectedSASLContinueMessage)
  testForMessage(SASLFinalBuffer, expectedSASLFinalMessage)

  testForMessage(paramStatusBuffer, expectedParameterStatusMessage)
  testForMessage(backendKeyDataBuffer, expectedBackendKeyDataMessage)
  testForMessage(readyForQueryBuffer, expectedReadyForQueryMessage)
  testForMessage(commandCompleteBuffer, expectedCommandCompleteMessage)
  testForMessage(notificationResponseBuffer, expectedNotificationResponseMessage)
  testForMessage(buffers.emptyQuery(), {
    name: 'emptyQuery',
    length: 4,
  })

  testForMessage(Buffer.from([0x6e, 0, 0, 0, 4]), {
    name: 'noData'
  })

  describe('rowDescription messages', function () {
    testForMessage(emptyRowDescriptionBuffer, expectedEmptyRowDescriptionMessage)
    testForMessage(oneRowDescBuff, expectedOneRowMessage)
    testForMessage(twoRowBuf, expectedTwoRowMessage)
  })

  describe('parsing rows', function () {
    describe('parsing empty row', function () {
      testForMessage(emptyRowFieldBuf, {
        name: 'dataRow',
        fieldCount: 0
      })
    })

    describe('parsing data row with fields', function () {
      testForMessage(oneFieldBuf, {
        name: 'dataRow',
        fieldCount: 1,
        fields: ['test']
      })
    })
  })

  describe('notice message', function () {
    // this uses the same logic as error message
    var buff = buffers.notice([{ type: 'C', value: 'code' }])
    testForMessage(buff, {
      name: 'notice',
      code: 'code'
    })
  })

  testForMessage(buffers.error([]), {
    name: 'error'
  })

  describe('with all the fields', function () {
    var buffer = buffers.error([{
      type: 'S',
      value: 'ERROR'
    }, {
      type: 'C',
      value: 'code'
    }, {
      type: 'M',
      value: 'message'
    }, {
      type: 'D',
      value: 'details'
    }, {
      type: 'H',
      value: 'hint'
    }, {
      type: 'P',
      value: '100'
    }, {
      type: 'p',
      value: '101'
    }, {
      type: 'q',
      value: 'query'
    }, {
      type: 'W',
      value: 'where'
    }, {
      type: 'F',
      value: 'file'
    }, {
      type: 'L',
      value: 'line'
    }, {
      type: 'R',
      value: 'routine'
    }, {
      type: 'Z', // ignored
      value: 'alsdkf'
    }])

    testForMessage(buffer, {
      name: 'error',
      severity: 'ERROR',
      code: 'code',
      message: 'message',
      detail: 'details',
      hint: 'hint',
      position: '100',
      internalPosition: '101',
      internalQuery: 'query',
      where: 'where',
      file: 'file',
      line: 'line',
      routine: 'routine'
    })
  })

  testForMessage(parseCompleteBuffer, {
    name: 'parseComplete'
  })

  testForMessage(bindCompleteBuffer, {
    name: 'bindComplete'
  })

  testForMessage(bindCompleteBuffer, {
    name: 'bindComplete'
  })

  testForMessage(buffers.closeComplete(), {
    name: 'closeComplete'
  })

  describe('parses portal suspended message', function () {
    testForMessage(portalSuspendedBuffer, {
      name: 'portalSuspended'
    })
  })

  describe('parses replication start message', function () {
    testForMessage(Buffer.from([0x57, 0x00, 0x00, 0x00, 0x04]), {
      name: 'replicationStart',
      length: 4
    })
  })

  describe('copy', () => {
    testForMessage(buffers.copyIn(0), {
      name: 'copyInResponse',
      length: 7,
      binary: false,
      columnTypes: []
    })

    testForMessage(buffers.copyIn(2), {
      name: 'copyInResponse',
      length: 11,
      binary: false,
      columnTypes: [0, 1]
    })

    testForMessage(buffers.copyOut(0), {
      name: 'copyOutResponse',
      length: 7,
      binary: false,
      columnTypes: []
    })

    testForMessage(buffers.copyOut(3), {
      name: 'copyOutResponse',
      length: 13,
      binary: false,
      columnTypes: [0, 1, 2]
    })

    testForMessage(buffers.copyDone(), {
      name: 'copyDone',
      length: 4,
    })

    testForMessage(buffers.copyData(Buffer.from([5, 6, 7])), {
      name: 'copyData',
      length: 7,
      chunk: Buffer.from([5, 6, 7])
    })
  })


  // since the data message on a stream can randomly divide the incomming
  // tcp packets anywhere, we need to make sure we can parse every single
  // split on a tcp message
  describe('split buffer, single message parsing', function () {
    var fullBuffer = buffers.dataRow([null, 'bang', 'zug zug', null, '!'])

    const parse = async (buffers: Buffer[]): Promise<any> => {
      const parser = new PgPacketStream();
      for (const buffer of buffers) {
        parser.write(buffer);
      }
      parser.end()
      const [msg] = await concat(parser)
      return msg;
    }

    it('parses when full buffer comes in', async function () {
      const message = await parse([fullBuffer]);
      assert.equal(message.fields.length, 5)
      assert.equal(message.fields[0], null)
      assert.equal(message.fields[1], 'bang')
      assert.equal(message.fields[2], 'zug zug')
      assert.equal(message.fields[3], null)
      assert.equal(message.fields[4], '!')
    })

    var testMessageRecievedAfterSpiltAt = async function (split: number) {
      var firstBuffer = Buffer.alloc(fullBuffer.length - split)
      var secondBuffer = Buffer.alloc(fullBuffer.length - firstBuffer.length)
      fullBuffer.copy(firstBuffer, 0, 0)
      fullBuffer.copy(secondBuffer, 0, firstBuffer.length)
      const message = await parse([firstBuffer, secondBuffer]);
      assert.equal(message.fields.length, 5)
      assert.equal(message.fields[0], null)
      assert.equal(message.fields[1], 'bang')
      assert.equal(message.fields[2], 'zug zug')
      assert.equal(message.fields[3], null)
      assert.equal(message.fields[4], '!')
    }

    it('parses when split in the middle', function () {
      testMessageRecievedAfterSpiltAt(6)
    })

    it('parses when split at end', function () {
      testMessageRecievedAfterSpiltAt(2)
    })

    it('parses when split at beginning', function () {
      testMessageRecievedAfterSpiltAt(fullBuffer.length - 2)
      testMessageRecievedAfterSpiltAt(fullBuffer.length - 1)
      testMessageRecievedAfterSpiltAt(fullBuffer.length - 5)
    })
  })

  describe('split buffer, multiple message parsing', function () {
    var dataRowBuffer = buffers.dataRow(['!'])
    var readyForQueryBuffer = buffers.readyForQuery()
    var fullBuffer = Buffer.alloc(dataRowBuffer.length + readyForQueryBuffer.length)
    dataRowBuffer.copy(fullBuffer, 0, 0)
    readyForQueryBuffer.copy(fullBuffer, dataRowBuffer.length, 0)

    const parse = (buffers: Buffer[]): Promise<any[]> => {
      const parser = new PgPacketStream();
      for (const buffer of buffers) {
        parser.write(buffer);
      }
      parser.end()
      return concat(parser)
    }

    var verifyMessages = function (messages: any[]) {
      assert.strictEqual(messages.length, 2)
      assert.deepEqual(messages[0], {
        name: 'dataRow',
        fieldCount: 1,
        length: 11,
        fields: ['!']
      })
      assert.equal(messages[0].fields[0], '!')
      assert.deepEqual(messages[1], {
        name: 'readyForQuery',
        length: 5,
        status: 'I'
      })
    }
    // sanity check
    it('recieves both messages when packet is not split', async function () {
      const messages = await parse([fullBuffer])
      verifyMessages(messages)
    })

    var splitAndVerifyTwoMessages = async function (split: number) {
      var firstBuffer = Buffer.alloc(fullBuffer.length - split)
      var secondBuffer = Buffer.alloc(fullBuffer.length - firstBuffer.length)
      fullBuffer.copy(firstBuffer, 0, 0)
      fullBuffer.copy(secondBuffer, 0, firstBuffer.length)
      const messages = await parse([firstBuffer, secondBuffer])
      verifyMessages(messages)
    }

    describe('recieves both messages when packet is split', function () {
      it('in the middle', function () {
        return splitAndVerifyTwoMessages(11)
      })
      it('at the front', function () {
        return Promise.all([
          splitAndVerifyTwoMessages(fullBuffer.length - 1),
          splitAndVerifyTwoMessages(fullBuffer.length - 4),
          splitAndVerifyTwoMessages(fullBuffer.length - 6)
        ])
      })

      it('at the end', function () {
        return Promise.all([
          splitAndVerifyTwoMessages(8),
          splitAndVerifyTwoMessages(1)
        ])
      })
    })
  })

})