import unittest, deques, sequtils
import chronos
import ../libp2p/stream/bufferstream

suite "BufferStream":
  test "push data to buffer":
    proc testPushTo(): Future[bool] {.async.} =
      proc writeHandler(data: seq[byte]) = discard
      let buff = newBufferStream(writeHandler, 16)
      check buff.len == 0
      var data: seq[char]
      data.add(@"12345")
      await buff.pushTo(cast[seq[byte]](data))
      check buff.len == 5
      result = true

    check:
      waitFor(testPushTo()) == true

  test "push and wait":
    proc testPushTo(): Future[bool] {.async.} =
      proc writeHandler(data: seq[byte]) = discard
      let buff = newBufferStream(writeHandler, 4)
      check buff.len == 0

      let fut = buff.pushTo(cast[seq[byte]](@"12345"))
      check buff.len == 4
      check buff.popFirst() == byte(ord('1'))
      await fut
      check buff.len == 4

      result = true

    check:
      waitFor(testPushTo()) == true

  test "read":
    proc testRead(): Future[bool] {.async.} =
      proc writeHandler(data: seq[byte]) = discard
      let buff = newBufferStream(writeHandler, 10)
      check buff.len == 0

      await buff.pushTo(cast[seq[byte]](@"12345"))
      check @"12345" == cast[string](await buff.read())

      result = true

    check:
      waitFor(testRead()) == true

  test "read with size":
    proc testRead(): Future[bool] {.async.} =
      proc writeHandler(data: seq[byte]) = discard
      let buff = newBufferStream(writeHandler, 10)
      check buff.len == 0

      await buff.pushTo(cast[seq[byte]](@"12345"))
      let data = cast[string](await buff.read(3))
      check ['1', '2', '3'] == data

      result = true

    check:
      waitFor(testRead()) == true

  test "read and wait":
    proc testRead(): Future[bool] {.async.} =
      proc writeHandler(data: seq[byte]) = discard
      let buff = newBufferStream(writeHandler, 10)
      check buff.len == 0

      await buff.pushTo(cast[seq[byte]](@"123"))
      check buff.len == 3
      let readFut = buff.read(5)
      await buff.pushTo(cast[seq[byte]](@"45"))
      check buff.len == 2

      check cast[string](await readFut) == ['1', '2', '3', '4', '5']

      result = true

    check:
      waitFor(testRead()) == true

  test "readExactly":
    proc testReadExactly(): Future[bool] {.async.} =
      proc writeHandler(data: seq[byte]) = discard
      let buff = newBufferStream(writeHandler, 10)
      check buff.len == 0

      await buff.pushTo(cast[seq[byte]](@"12345"))
      check buff.len == 5
      var data: seq[byte] = newSeq[byte](2)
      await buff.readExactly(addr data[0], 2)
      check cast[string](data) == @['1', '2']
      result = true

    check:
      waitFor(testReadExactly()) == true

  test "readLine":
    proc testReadLine(): Future[bool] {.async.} =
      proc writeHandler(data: seq[byte]) = discard
      let buff = newBufferStream(writeHandler, 16)
      check buff.len == 0

      await buff.pushTo(cast[seq[byte]](@"12345\n67890"))
      check buff.len == 11
      check "12345" == await buff.readLine(0, "\n")
      result = true

    check:
      waitFor(testReadLine()) == true

  test "readOnce":
    proc testReadOnce(): Future[bool] {.async.} =
      proc writeHandler(data: seq[byte]) = discard
      let buff = newBufferStream(writeHandler, 10)
      check buff.len == 0

      var data: seq[byte] = newSeq[byte](3)
      let readFut = buff.readOnce(addr data[0], 5)
      await buff.pushTo(cast[seq[byte]](@"123"))
      check buff.len == 3

      check (await readFut) == 3
      check cast[string](data) == @['1', '2', '3']
      result = true

    check:
      waitFor(testReadOnce()) == true

  test "readUntil":
    proc testReadUntil(): Future[bool] {.async.} =
      proc writeHandler(data: seq[byte]) = discard
      let buff = newBufferStream(writeHandler, 10)
      check buff.len == 0

      var data: seq[byte] = newSeq[byte](3)
      await buff.pushTo(cast[seq[byte]](@"123$45"))
      check buff.len == 6
      let readFut = buff.readUntil(addr data[0], 5, @[byte('$')])

      check (await readFut) == 4
      check cast[string](data) == @['1', '2', '3']
      result = true

    check:
      waitFor(testReadUntil()) == true

  test "write ptr":
    proc testWritePtr(): Future[bool] {.async.} =
      proc writeHandler(data: seq[byte]) = 
        check cast[string](data) == "Hello!"

      let buff = newBufferStream(writeHandler, 10)
      check buff.len == 0

      var data = "Hello!"
      await buff.write(addr data[0], data.len)
      result = true

    check:
      waitFor(testWritePtr()) == true

  test "write string":
    proc testWritePtr(): Future[bool] {.async.} =
      proc writeHandler(data: seq[byte]) = 
        check cast[string](data) == "Hello!"

      let buff = newBufferStream(writeHandler, 10)
      check buff.len == 0

      await buff.write("Hello!", 6)
      result = true

    check:
      waitFor(testWritePtr()) == true

  test "write bytes":
    proc testWritePtr(): Future[bool] {.async.} =
      proc writeHandler(data: seq[byte]) = 
        check cast[string](data) == "Hello!"

      let buff = newBufferStream(writeHandler, 10)
      check buff.len == 0

      await buff.write(cast[seq[byte]](toSeq("Hello!".items)), 6)
      result = true

    check:
      waitFor(testWritePtr()) == true