#                Chronos Test Suite
#            (c) Copyright 2018-Present
#         Status Research & Development GmbH
#
#              Licensed under either of
#  Apache License, version 2.0, (LICENSE-APACHEv2)
#              MIT license (LICENSE-MIT)

import unittest
import ../chronos

proc testFuture1(): Future[int] {.async.} =
  await sleepAsync(1.milliseconds)

proc testFuture2(): Future[int] {.async.} =
  return 1

proc testFuture3(): Future[int] {.async.} =
  result = await testFuture2()

proc testFuture100(): Future[int] {.async.} =
  await sleepAsync(100.milliseconds)

proc testFuture4(): Future[int] {.async.} =
  ## Test for not immediately completed future and timeout = -1
  result = 0
  try:
    var res = await wait(testFuture1(), InfiniteDuration)
    result = 1
  except:
    result = 0

  if result == 0:
    return -1

  ## Test for immediately completed future and timeout = -1
  result = 0
  try:
    var res = await wait(testFuture2(), InfiniteDuration)
    result = 2
  except:
    result = 0

  if result == 0:
    return -2

  ## Test for not immediately completed future and timeout = 0
  result = 0
  try:
    var res = await wait(testFuture1(), 0.milliseconds)
  except AsyncTimeoutError:
    result = 3

  if result == 0:
    return -3

  ## Test for immediately completed future and timeout = 0
  result = 0
  try:
    var res = await wait(testFuture2(), 0.milliseconds)
    result = 4
  except:
    result = 0

  if result == 0:
    return -4

  ## Test for future which cannot be completed in timeout period
  result = 0
  try:
    var res = await wait(testFuture100(), 50.milliseconds)
  except AsyncTimeoutError:
    result = 5

  if result == 0:
    return -5

  ## Test for future which will be completed before timeout exceeded.
  try:
    var res = await wait(testFuture100(), 500.milliseconds)
    result = 6
  except:
    result = -6

proc test1(): bool =
  var fut = testFuture1()
  poll()
  poll()
  if not fut.finished:
    poll()
  result = fut.finished

proc test2(): bool =
  var fut = testFuture3()
  result = fut.finished

proc test3(): string =
  var testResult = ""
  var fut = testFuture1()
  fut.addCallback proc(udata: pointer) =
    testResult &= "1"
  fut.addCallback proc(udata: pointer) =
    testResult &= "2"
  fut.addCallback proc(udata: pointer) =
    testResult &= "3"
  fut.addCallback proc(udata: pointer) =
    testResult &= "4"
  fut.addCallback proc(udata: pointer) =
    testResult &= "5"
  discard waitFor(fut)
  poll()
  if fut.finished:
    result = testResult

proc test4(): string =
  var testResult = ""
  var fut = testFuture1()
  proc cb1(udata: pointer) =
    testResult &= "1"
  proc cb2(udata: pointer) =
    testResult &= "2"
  proc cb3(udata: pointer) =
    testResult &= "3"
  proc cb4(udata: pointer) =
    testResult &= "4"
  proc cb5(udata: pointer) =
    testResult &= "5"
  fut.addCallback cb1
  fut.addCallback cb2
  fut.addCallback cb3
  fut.addCallback cb4
  fut.addCallback cb5
  fut.removeCallback cb3
  discard waitFor(fut)
  poll()
  if fut.finished:
    result = testResult

proc test5(): int =
  result = waitFor(testFuture4())

proc testAllVarargs(): int =
  var completedFutures = 0

  proc vlient1() {.async.} =
    await sleepAsync(100.milliseconds)
    inc(completedFutures)

  proc vlient2() {.async.} =
    await sleepAsync(200.milliseconds)
    inc(completedFutures)

  proc vlient3() {.async.} =
    await sleepAsync(300.milliseconds)
    inc(completedFutures)

  proc vlient4() {.async.} =
    await sleepAsync(400.milliseconds)
    inc(completedFutures)

  proc vlient5() {.async.} =
    await sleepAsync(500.milliseconds)
    inc(completedFutures)

  proc vlient1f() {.async.} =
    await sleepAsync(100.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  proc vlient2f() {.async.} =
    await sleepAsync(100.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  proc vlient3f() {.async.} =
    await sleepAsync(100.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  proc vlient4f() {.async.} =
    await sleepAsync(100.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  proc vlient5f() {.async.} =
    await sleepAsync(100.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  proc client1(): Future[int] {.async.} =
    await sleepAsync(100.milliseconds)
    inc(completedFutures)
    result = 1

  proc client2(): Future[int] {.async.} =
    await sleepAsync(200.milliseconds)
    inc(completedFutures)
    result = 1

  proc client3(): Future[int] {.async.} =
    await sleepAsync(300.milliseconds)
    inc(completedFutures)
    result = 1

  proc client4(): Future[int] {.async.} =
    await sleepAsync(400.milliseconds)
    inc(completedFutures)
    result = 1

  proc client5(): Future[int] {.async.} =
    await sleepAsync(500.milliseconds)
    inc(completedFutures)
    result = 1

  proc client1f(): Future[int] {.async.} =
    await sleepAsync(100.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  proc client2f(): Future[int] {.async.} =
    await sleepAsync(200.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  proc client3f(): Future[int] {.async.} =
    await sleepAsync(300.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  proc client4f(): Future[int] {.async.} =
    await sleepAsync(400.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  proc client5f(): Future[int] {.async.} =
    await sleepAsync(500.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  waitFor(all(vlient1(), vlient2(), vlient3(), vlient4(), vlient5()))
  # 5 completed futures = 5
  result += completedFutures
  completedFutures = 0
  try:
    waitFor(all(vlient1(), vlient1f(),
                vlient2(), vlient2f(),
                vlient3(), vlient3f(),
                vlient4(), vlient4f(),
                vlient5(), vlient5f()))
    result -= 10000
  except:
    discard
  # 10 completed futures = 10
  result += completedFutures

  completedFutures = 0
  var res = waitFor(all(client1(), client2(), client3(), client4(), client5()))
  for item in res:
    result += item
  # 5 completed futures + 5 values = 10
  result += completedFutures

  completedFutures = 0
  try:
    var res = waitFor(all(client1(), client1f(),
                          client2(), client2f(),
                          client3(), client3f(),
                          client4(), client4f(),
                          client5(), client5f()))
    result -= 10000
  except:
    discard
  # 10 completed futures = 10
  result += completedFutures

proc testAllSeq(): int =
  var completedFutures = 0
  var vfutures = newSeq[Future[void]]()
  var nfutures = newSeq[Future[int]]()

  proc vlient1() {.async.} =
    await sleepAsync(100.milliseconds)
    inc(completedFutures)

  proc vlient2() {.async.} =
    await sleepAsync(200.milliseconds)
    inc(completedFutures)

  proc vlient3() {.async.} =
    await sleepAsync(300.milliseconds)
    inc(completedFutures)

  proc vlient4() {.async.} =
    await sleepAsync(400.milliseconds)
    inc(completedFutures)

  proc vlient5() {.async.} =
    await sleepAsync(500.milliseconds)
    inc(completedFutures)

  proc vlient1f() {.async.} =
    await sleepAsync(100.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  proc vlient2f() {.async.} =
    await sleepAsync(100.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  proc vlient3f() {.async.} =
    await sleepAsync(100.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  proc vlient4f() {.async.} =
    await sleepAsync(100.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  proc vlient5f() {.async.} =
    await sleepAsync(100.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  proc client1(): Future[int] {.async.} =
    await sleepAsync(100.milliseconds)
    inc(completedFutures)
    result = 1

  proc client2(): Future[int] {.async.} =
    await sleepAsync(200.milliseconds)
    inc(completedFutures)
    result = 1

  proc client3(): Future[int] {.async.} =
    await sleepAsync(300.milliseconds)
    inc(completedFutures)
    result = 1

  proc client4(): Future[int] {.async.} =
    await sleepAsync(400.milliseconds)
    inc(completedFutures)
    result = 1

  proc client5(): Future[int] {.async.} =
    await sleepAsync(500.milliseconds)
    inc(completedFutures)
    result = 1

  proc client1f(): Future[int] {.async.} =
    await sleepAsync(100.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  proc client2f(): Future[int] {.async.} =
    await sleepAsync(200.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  proc client3f(): Future[int] {.async.} =
    await sleepAsync(300.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  proc client4f(): Future[int] {.async.} =
    await sleepAsync(400.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  proc client5f(): Future[int] {.async.} =
    await sleepAsync(500.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  vfutures.setLen(0)
  for i in 0..<10:
    vfutures.add(vlient1())
    vfutures.add(vlient2())
    vfutures.add(vlient3())
    vfutures.add(vlient4())
    vfutures.add(vlient5())

  waitFor(all(vfutures))
  # 5 * 10 completed futures = 50
  result += completedFutures

  completedFutures = 0
  vfutures.setLen(0)
  for i in 0..<10:
    vfutures.add(vlient1())
    vfutures.add(vlient1f())
    vfutures.add(vlient2())
    vfutures.add(vlient2f())
    vfutures.add(vlient3())
    vfutures.add(vlient3f())
    vfutures.add(vlient4())
    vfutures.add(vlient4f())
    vfutures.add(vlient5())
    vfutures.add(vlient5f())

  try:
    waitFor(all(vfutures))
    result -= 10000
  except:
    discard
  # 10 * 10 completed futures = 100
  result += completedFutures

  completedFutures = 0
  nfutures.setLen(0)
  for i in 0..<10:
    nfutures.add(client1())
    nfutures.add(client2())
    nfutures.add(client3())
    nfutures.add(client4())
    nfutures.add(client5())

  var res = waitFor(all(nfutures))
  for i in 0..<len(nfutures):
    result += res[i]
  # 5 * 10 completed futures + 5 * 10 results = 100
  result += completedFutures

  completedFutures = 0
  nfutures.setLen(0)
  for i in 0..<10:
    nfutures.add(client1())
    nfutures.add(client1f())
    nfutures.add(client2())
    nfutures.add(client2f())
    nfutures.add(client3())
    nfutures.add(client3f())
    nfutures.add(client4())
    nfutures.add(client4f())
    nfutures.add(client5())
    nfutures.add(client5f())

  try:
    var results = waitFor(all(nfutures))
    result -= 10000
  except:
    discard

  # 10 * 10 completed futures + 0 * 10 results = 100
  result += completedFutures

proc testAsyncDiscard(): int =
  var completedFutures = 0

  proc client1() {.async.} =
    await sleepAsync(100.milliseconds)
    inc(completedFutures)

  proc client2() {.async.} =
    await sleepAsync(200.milliseconds)
    inc(completedFutures)

  proc client3() {.async.} =
    await sleepAsync(300.milliseconds)
    inc(completedFutures)

  proc client4() {.async.} =
    await sleepAsync(400.milliseconds)
    inc(completedFutures)

  proc client5() {.async.} =
    await sleepAsync(500.milliseconds)
    inc(completedFutures)

  proc client1f() {.async.} =
    await sleepAsync(100.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  proc client2f() {.async.} =
    await sleepAsync(200.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  proc client3f() {.async.} =
    await sleepAsync(300.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  proc client4f() {.async.} =
    await sleepAsync(400.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  proc client5f() {.async.} =
    await sleepAsync(500.milliseconds)
    inc(completedFutures)
    if true:
      raise newException(ValueError, "")

  asyncDiscard client1()
  asyncDiscard client1f()
  asyncDiscard client2()
  asyncDiscard client2f()
  asyncDiscard client3()
  asyncDiscard client3f()
  asyncDiscard client4()
  asyncDiscard client4f()
  asyncDiscard client5()
  asyncDiscard client5f()

  waitFor(sleepAsync(2000.milliseconds))
  result = completedFutures

proc testAllZero(): bool =
  var tseq = newSeq[Future[int]]()
  var fut = all(tseq)
  result = fut.finished

when isMainModule:
  suite "Future[T] behavior test suite":
    test "Async undefined behavior (#7758) test":
      check test1() == true
    test "Immediately completed asynchronous procedure test":
      check test2() == true
    test "Future[T] callbacks are invoked in reverse order (#7197) test":
      check test3() == "12345"
    test "Future[T] callbacks not changing order after removeCallback()":
      check test4() == "1245"
    test "wait[T]() test":
      check test5() == 6
    test "all[T](varargs) test":
      check testAllVarargs() == 35
    test "all[T](seq) test":
      check testAllSeq() == 350
    test "all[T](zero) test":
      check testAllZero() == true
    test "asyncDiscard() test":
      check testAsyncDiscard() == 10