# Copyright 2022 The JAX Authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import io
import re
import textwrap
import unittest

from typing import IO, Sequence

from absl.testing import absltest
import jax
from jax import config
from jax.experimental import pjit
from jax._src import debugger
from jax._src import test_util as jtu
from jax._src import xla_bridge
import jax.numpy as jnp
import numpy as np

config.parse_flags_with_absl()

def make_fake_stdin_stdout(commands: Sequence[str]) -> tuple[IO[str], io.StringIO]:
  fake_stdin = io.StringIO()
  fake_stdin.truncate(0)
  for command in commands:
    fake_stdin.write(command + "\n")
  fake_stdin.seek(0)
  return fake_stdin, io.StringIO()

def _format_multiline(text):
  return textwrap.dedent(text).lstrip()

prev_xla_flags = None

def setUpModule():
  global prev_xla_flags
  # This will control the CPU devices. On TPU we always have 2 devices
  prev_xla_flags = jtu.set_host_platform_device_count(2)

# Reset to previous configuration in case other test modules will be run.
def tearDownModule():
  prev_xla_flags()

foo = 2

class CliDebuggerTest(jtu.JaxTestCase):

  def test_debugger_eof(self):
    stdin, stdout = make_fake_stdin_stdout([])

    def f(x):
      y = jnp.sin(x)
      debugger.breakpoint(stdin=stdin, stdout=stdout, backend="cli")
      return y
    with self.assertRaises(SystemExit):
      f(2.)
      jax.effects_barrier()

  def test_debugger_can_continue(self):
    stdin, stdout = make_fake_stdin_stdout(["c"])

    def f(x):
      y = jnp.sin(x)
      debugger.breakpoint(stdin=stdin, stdout=stdout, backend="cli")
      return y
    f(2.)
    jax.effects_barrier()
    expected = _format_multiline(r"""
    Entering jdb:
    (jdb) """)
    self.assertEqual(stdout.getvalue(), expected)

  def test_debugger_can_print_value(self):
    stdin, stdout = make_fake_stdin_stdout(["p x", "c"])

    def f(x):
      y = jnp.sin(x)
      debugger.breakpoint(stdin=stdin, stdout=stdout, backend="cli")
      return y
    expected = _format_multiline(r"""
    Entering jdb:
    (jdb) Array(2., dtype=float32)
    (jdb) """)
    f(jnp.array(2., jnp.float32))
    jax.effects_barrier()
    self.assertEqual(stdout.getvalue(), expected)

  def test_debugger_can_print_value_in_jit(self):
    if xla_bridge.get_backend().runtime_type == 'stream_executor':
      raise unittest.SkipTest('Host callback not supported for runtime type: stream_executor.')

    stdin, stdout = make_fake_stdin_stdout(["p x", "c"])

    @jax.jit
    def f(x):
      y = jnp.sin(x)
      debugger.breakpoint(stdin=stdin, stdout=stdout, backend="cli")
      return y
    expected = _format_multiline(r"""
    Entering jdb:
    (jdb) array(2., dtype=float32)
    (jdb) """)
    f(jnp.array(2., jnp.float32))
    jax.effects_barrier()
    self.assertEqual(stdout.getvalue(), expected)

  def test_debugger_can_print_multiple_values(self):
    if xla_bridge.get_backend().runtime_type == 'stream_executor':
      raise unittest.SkipTest('Host callback not supported for runtime type: stream_executor.')

    stdin, stdout = make_fake_stdin_stdout(["p x, y", "c"])

    @jax.jit
    def f(x):
      y = x + 1.
      debugger.breakpoint(stdin=stdin, stdout=stdout, backend="cli")
      return y
    expected = _format_multiline(r"""
    Entering jdb:
    (jdb) (array(2., dtype=float32), array(3., dtype=float32))
    (jdb) """)
    f(jnp.array(2., jnp.float32))
    jax.effects_barrier()
    self.assertEqual(stdout.getvalue(), expected)

  def test_debugger_can_print_context(self):
    if xla_bridge.get_backend().runtime_type == 'stream_executor':
      raise unittest.SkipTest('Host callback not supported for runtime type: stream_executor.')

    stdin, stdout = make_fake_stdin_stdout(["l", "c"])

    @jax.jit
    def f(x):
      y = jnp.sin(x)
      debugger.breakpoint(stdin=stdin, stdout=stdout, backend="cli")
      return y
    f(2.)
    jax.effects_barrier()
    expected = _format_multiline(r"""
    Entering jdb:
    \(jdb\) > .*debugger_test\.py\([0-9]+\)
            @jax\.jit
            def f\(x\):
              y = jnp\.sin\(x\)
    ->        debugger\.breakpoint\(stdin=stdin, stdout=stdout, backend="cli"\)
              return y
    .*
    \(jdb\) """)
    self.assertRegex(stdout.getvalue(), expected)

  def test_debugger_can_print_backtrace(self):
    if xla_bridge.get_backend().runtime_type == 'stream_executor':
      raise unittest.SkipTest('Host callback not supported for runtime type: stream_executor.')

    stdin, stdout = make_fake_stdin_stdout(["bt", "c"])

    @jax.jit
    def f(x):
      y = jnp.sin(x)
      debugger.breakpoint(stdin=stdin, stdout=stdout, backend="cli")
      return y
    expected = _format_multiline(r"""
    Entering jdb:.*
    \(jdb\) Traceback:.*
    """)
    f(2.)
    jax.effects_barrier()
    self.assertRegex(stdout.getvalue(), expected)

  def test_debugger_can_work_with_multiple_stack_frames(self):
    if xla_bridge.get_backend().runtime_type == 'stream_executor':
      raise unittest.SkipTest('Host callback not supported for runtime type: stream_executor.')

    stdin, stdout = make_fake_stdin_stdout(["l", "u", "p x", "d", "c"])

    def f(x):
      y = jnp.sin(x)
      debugger.breakpoint(stdin=stdin, stdout=stdout, backend="cli")
      return y

    @jax.jit
    def g(x):
      y = f(x)
      return jnp.exp(y)
    expected = _format_multiline(r"""
    Entering jdb:
    \(jdb\) > .*debugger_test\.py\([0-9]+\)
            def f\(x\):
              y = jnp\.sin\(x\)
    ->        debugger\.breakpoint\(stdin=stdin, stdout=stdout, backend="cli"\)
              return y
    .*
    \(jdb\) > .*debugger_test\.py\([0-9]+\).*
            @jax\.jit
            def g\(x\):
    ->        y = f\(x\)
              return jnp\.exp\(y\)
    .*
    \(jdb\) array\(2\., dtype=float32\)
    \(jdb\) > .*debugger_test\.py\([0-9]+\)
            def f\(x\):
              y = jnp\.sin\(x\)
    ->        debugger\.breakpoint\(stdin=stdin, stdout=stdout, backend="cli"\)
              return y
    .*
    \(jdb\) """)
    g(jnp.array(2., jnp.float32))
    jax.effects_barrier()
    self.assertRegex(stdout.getvalue(), expected)

  def test_can_use_multiple_breakpoints(self):
    if xla_bridge.get_backend().runtime_type == 'stream_executor':
      raise unittest.SkipTest('Host callback not supported for runtime type: stream_executor.')

    stdin, stdout = make_fake_stdin_stdout(["p y", "c", "p y", "c"])

    def f(x):
      y = x + 1.
      debugger.breakpoint(stdin=stdin, stdout=stdout, ordered=True,
          backend="cli")
      return y

    @jax.jit
    def g(x):
      y = f(x) * 2.
      debugger.breakpoint(stdin=stdin, stdout=stdout, ordered=True,
          backend="cli")
      return jnp.exp(y)
    expected = _format_multiline(r"""
    Entering jdb:
    (jdb) array(3., dtype=float32)
    (jdb) Entering jdb:
    (jdb) array(6., dtype=float32)
    (jdb) """)
    g(jnp.array(2., jnp.float32))
    jax.effects_barrier()
    self.assertEqual(stdout.getvalue(), expected)

  def test_debugger_works_with_vmap(self):
    if xla_bridge.get_backend().runtime_type == 'stream_executor':
      raise unittest.SkipTest('Host callback not supported for runtime type: stream_executor.')

    stdin, stdout = make_fake_stdin_stdout(["p y", "c", "p y", "c"])

    # On TPU, the breakpoints can be reordered inside of vmap but can be fixed
    # by ordering sends.
    # TODO(sharadmv): change back to ordered = False when sends are ordered
    ordered = jax.default_backend() == "tpu"

    def f(x):
      y = x + 1.
      debugger.breakpoint(stdin=stdin, stdout=stdout, ordered=ordered,
          backend="cli")
      return 2. * y

    @jax.jit
    @jax.vmap
    def g(x):
      y = f(x)
      return jnp.exp(y)
    expected = _format_multiline(r"""
    Entering jdb:
    (jdb) array(1., dtype=float32)
    (jdb) Entering jdb:
    (jdb) array(2., dtype=float32)
    (jdb) """)
    g(jnp.arange(2., dtype=jnp.float32))
    jax.effects_barrier()
    self.assertEqual(stdout.getvalue(), expected)

  def test_debugger_works_with_pmap(self):
    if xla_bridge.get_backend().runtime_type == 'stream_executor':
      raise unittest.SkipTest('Host callback not supported for runtime type: stream_executor.')

    if jax.local_device_count() < 2:
      raise unittest.SkipTest("Test requires >= 2 devices.")

    stdin, stdout = make_fake_stdin_stdout(["p y", "c", "p y", "c"])

    def f(x):
      y = jnp.sin(x)
      debugger.breakpoint(stdin=stdin, stdout=stdout, backend="cli")
      return y

    @jax.pmap
    def g(x):
      y = f(x)
      return jnp.exp(y)
    expected = _format_multiline(r"""
    Entering jdb:
    \(jdb\) array\(.*, dtype=float32\)
    \(jdb\) Entering jdb:
    \(jdb\) array\(.*, dtype=float32\)
    \(jdb\) """)
    g(jnp.arange(2., dtype=jnp.float32))
    jax.effects_barrier()
    self.assertRegex(stdout.getvalue(), expected)

  def test_debugger_works_with_pjit(self):
    if xla_bridge.get_backend().runtime_type == 'stream_executor':
      raise unittest.SkipTest('Host callback not supported for runtime type: stream_executor.')

    if jax.default_backend() != "tpu":
      raise unittest.SkipTest("`pjit` doesn't work with CustomCall.")

    stdin, stdout = make_fake_stdin_stdout(["p y", "c"])

    def f(x):
      y = x + 1
      debugger.breakpoint(stdin=stdin, stdout=stdout, backend="cli")
      return y

    def g(x):
      y = f(x)
      return jnp.exp(y)
    g = pjit.pjit(
        g,
        in_shardings=jax.sharding.PartitionSpec("dev"),
        out_shardings=jax.sharding.PartitionSpec("dev"),
    )
    with jax.sharding.Mesh(np.array(jax.devices()), ["dev"]):
      arr = (1 + np.arange(8)).astype(np.int32)
      expected = _format_multiline(r"""
      Entering jdb:
      \(jdb\) {}
      \(jdb\) """.format(re.escape(repr(arr))))
      g(jnp.arange(8, dtype=jnp.int32))
      jax.effects_barrier()
      self.assertRegex(stdout.getvalue(), expected)

  def test_debugger_uses_local_before_global_scope(self):
    stdin, stdout = make_fake_stdin_stdout(["p foo", "c"])

    foo = "outer"

    def f(x):
      foo = "inner"
      debugger.breakpoint(stdin=stdin, stdout=stdout, backend="cli")
      del foo
      return x

    del foo
    expected = _format_multiline(r"""
    Entering jdb:
    \(jdb\) 'inner'
    \(jdb\) """)
    f(2.)
    jax.effects_barrier()
    self.assertRegex(stdout.getvalue(), expected)

  def test_debugger_accesses_globals(self):
    if xla_bridge.get_backend().runtime_type == 'stream_executor':
      raise unittest.SkipTest('Host callback not supported for runtime type: stream_executor.')

    stdin, stdout = make_fake_stdin_stdout(["p foo", "c"])

    @jax.jit
    def g():
      debugger.breakpoint(stdin=stdin, stdout=stdout, backend="cli")

    expected = _format_multiline(r"""
    Entering jdb:
    \(jdb\) \*\*\* NameError: name 'foo' is not defined
    \(jdb\) """)
    g()
    jax.effects_barrier()
    self.assertRegex(stdout.getvalue(), expected)

  def test_can_limit_num_frames(self):
    if xla_bridge.get_backend().runtime_type == 'stream_executor':
      raise unittest.SkipTest('Host callback not supported for runtime type: stream_executor.')
    stdin, stdout = make_fake_stdin_stdout(["u", "p x", "c"])

    def g():
      debugger.breakpoint(stdin=stdin, stdout=stdout, backend="cli",
                          num_frames=2)

    @jax.jit
    def f():
      x = 2
      g()
      return x
    _ = f()
    expected = _format_multiline(r"""
    Entering jdb:
    \(jdb\) .*
    .*
    .*
    .*
    .*
    .*
    .*
    \(jdb\) 2
    \(jdb\) """)
    jax.effects_barrier()
    self.assertRegex(stdout.getvalue(), expected)

    stdin, stdout = make_fake_stdin_stdout(["u", "u", "c"])

    def g2():
      debugger.breakpoint(stdin=stdin, stdout=stdout, backend="cli",
                          num_frames=2)

    @jax.jit
    def f2():
      x = 2
      g2()
      return x

    expected = ".*At topmost frame.*"
    _ = f2()
    jax.effects_barrier()
    self.assertRegex(stdout.getvalue(), expected)

  def test_can_handle_dictionaries_with_unsortable_keys(self):
    if xla_bridge.get_backend().runtime_type == 'stream_executor':
      raise unittest.SkipTest('Host callback not supported for runtime type: stream_executor.')

    stdin, stdout = make_fake_stdin_stdout(["p x", "p weird_dict",
                                            "p weirder_dict", "c"])

    @jax.jit
    def f():
      weird_dict = {(lambda x: x): 2., (lambda x: x * 2): 3}
      weirder_dict = {(lambda x: x): weird_dict}
      x = 2.
      debugger.breakpoint(stdin=stdin, stdout=stdout, backend="cli")
      del weirder_dict
      return x
    expected = _format_multiline(r"""
    Entering jdb:
    \(jdb\) 2.0
    \(jdb\) <cant_flatten>
    \(jdb\) <cant_flatten>
    \(jdb\) """)
    _ = f()
    jax.effects_barrier()
    self.assertRegex(stdout.getvalue(), expected)

if __name__ == '__main__':
  absltest.main(testLoader=jtu.JaxTestLoader())
