"""Tests for debugging machinery."""

# Copyright (c) IPython Development Team.
# Distributed under the terms of the Modified BSD License.

import builtins
import os
import sys
import platform
from pathlib import Path

from tempfile import NamedTemporaryFile, TemporaryDirectory
from textwrap import dedent
from unittest.mock import patch

from IPython.core import debugger
from IPython.testing import IPYTHON_TESTING_TIMEOUT_SCALE
from IPython.testing.decorators import skip_win32
import pytest

# -----------------------------------------------------------------------------
# Helper classes, from CPython's Pdb test suite
# -----------------------------------------------------------------------------


class _FakeInput(object):
    """
    A fake input stream for pdb's interactive debugger.  Whenever a
    line is read, print it (to simulate the user typing it), and then
    return it.  The set of lines to return is specified in the
    constructor; they should not have trailing newlines.
    """

    def __init__(self, lines):
        self.lines = iter(lines)

    def readline(self):
        line = next(self.lines)
        print(line)
        return line + "\n"


class PdbTestInput(object):
    """Context manager that makes testing Pdb in doctests easier."""

    def __init__(self, input):
        self.input = input

    def __enter__(self):
        self.real_stdin = sys.stdin
        sys.stdin = _FakeInput(self.input)

    def __exit__(self, *exc):
        sys.stdin = self.real_stdin


# -----------------------------------------------------------------------------
# Tests
# -----------------------------------------------------------------------------


def test_ipdb_magics():
    '''Test calling some IPython magics from ipdb.

    First, set up some test functions and classes which we can inspect.

    In [1]: class ExampleClass(object):
       ...:    """Docstring for ExampleClass."""
       ...:    def __init__(self):
       ...:        """Docstring for ExampleClass.__init__"""
       ...:        pass
       ...:    def __str__(self):
       ...:        return "ExampleClass()"

    In [2]: def example_function(x, y, z="hello"):
       ...:     """Docstring for example_function."""
       ...:     pass

    In [3]: old_trace = sys.gettrace()

    Create a function which triggers ipdb.

    In [4]: def trigger_ipdb():
       ...:    a = ExampleClass()
       ...:    debugger.Pdb().set_trace()

    Run ipdb with faked input & check output. Because of a difference between
    Python 3.13 & older versions, the first bit of the output is inconsistent.
    We need to use ... to accommodate that, so the examples have to use IPython
    prompts so that ... is distinct from the Python PS2 prompt.

    In [5]: with PdbTestInput([
       ...:    'pdef example_function',
       ...:    'pdoc ExampleClass',
       ...:    'up',
       ...:    'down',
       ...:    'list',
       ...:    'pinfo a',
       ...:    'll',
       ...:    'continue',
       ...: ]):
       ...:     trigger_ipdb()
    ...> <doctest ...>(3)trigger_ipdb()
          1 def trigger_ipdb():
          2    a = ExampleClass()
    ----> 3    debugger.Pdb().set_trace()
    <BLANKLINE>
    ipdb> pdef example_function
     example_function(x, y, z='hello')
     ipdb> pdoc ExampleClass
    Class docstring:
        Docstring for ExampleClass.
    Init docstring:
        Docstring for ExampleClass.__init__
    ipdb> up
    > <doctest ...>(11)<module>()
          7    'pinfo a',
          8    'll',
          9    'continue',
         10 ]):
    ---> 11     trigger_ipdb()
    <BLANKLINE>
    ipdb> down...
    > <doctest ...>(3)trigger_ipdb()
          1 def trigger_ipdb():
          2    a = ExampleClass()
    ----> 3    debugger.Pdb().set_trace()
    <BLANKLINE>
    ipdb> list
          1 def trigger_ipdb():
          2    a = ExampleClass()
    ----> 3    debugger.Pdb().set_trace()
    <BLANKLINE>
    ipdb> pinfo a
    Type:           ExampleClass
    String form:    ExampleClass()
    Namespace:      Local...
    Docstring:      Docstring for ExampleClass.
    Init docstring: Docstring for ExampleClass.__init__
    ipdb> ll
          1 def trigger_ipdb():
          2    a = ExampleClass()
    ----> 3    debugger.Pdb().set_trace()
    <BLANKLINE>
    ipdb> continue

    Restore previous trace function, e.g. for coverage.py

    In [6]: sys.settrace(old_trace)
    '''


def test_ipdb_closure():
    """Test evaluation of expressions which depend on closure.

    In [1]: old_trace = sys.gettrace()

    Create a function which triggers ipdb.

    In [2]: def trigger_ipdb():
       ...:    debugger.Pdb().set_trace()

    In [3]: with PdbTestInput([
       ...:    'x = 1; sum(x * i for i in range(5))',
       ...:    'continue',
       ...: ]):
       ...:     trigger_ipdb()
    ...> <doctest ...>(2)trigger_ipdb()
          1 def trigger_ipdb():
    ----> 2    debugger.Pdb().set_trace()
    <BLANKLINE>
    ipdb> x = 1; sum(x * i for i in range(5))
    ipdb> continue

    Restore previous trace function, e.g. for coverage.py

    In [4]: sys.settrace(old_trace)
    """


def test_ipdb_magics2():
    """Test ipdb with a very short function.

    >>> old_trace = sys.gettrace()

    >>> def bar():
    ...     pass

    Run ipdb.

    >>> with PdbTestInput([
    ...    'continue',
    ... ]):
    ...     debugger.Pdb().runcall(bar)
    > <doctest ...>(2)bar()
          1 def bar():
    ----> 2    pass
    <BLANKLINE>
    ipdb> continue

    Restore previous trace function, e.g. for coverage.py

    >>> sys.settrace(old_trace)
    """


def can_quit():
    """Test that quit work in ipydb

    >>> old_trace = sys.gettrace()

    >>> def bar():
    ...     pass

    >>> with PdbTestInput([
    ...    'quit',
    ... ]):
    ...     debugger.Pdb().runcall(bar)
    > <doctest ...>(2)bar()
            1 def bar():
    ----> 2    pass
    <BLANKLINE>
    ipdb> quit

    Restore previous trace function, e.g. for coverage.py

    >>> sys.settrace(old_trace)
    """


def can_exit():
    """Test that quit work in ipydb

    >>> old_trace = sys.gettrace()

    >>> def bar():
    ...     pass

    >>> with PdbTestInput([
    ...    'exit',
    ... ]):
    ...     debugger.Pdb().runcall(bar)
    > <doctest ...>(2)bar()
            1 def bar():
    ----> 2    pass
    <BLANKLINE>
    ipdb> exit

    Restore previous trace function, e.g. for coverage.py

    >>> sys.settrace(old_trace)
    """


def test_interruptible_core_debugger():
    """The debugger can be interrupted.

    The presumption is there is some mechanism that causes a KeyboardInterrupt
    (this is implemented in ipykernel).  We want to ensure the
    KeyboardInterrupt cause debugging to cease.
    """

    def raising_input(msg="", called=[0]):
        called[0] += 1
        assert called[0] == 1, "input() should only be called once!"
        raise KeyboardInterrupt()

    tracer_orig = sys.gettrace()
    try:
        with patch.object(builtins, "input", raising_input):
            debugger.InterruptiblePdb().set_trace()
            # The way this test will fail is by set_trace() never exiting,
            # resulting in a timeout by the test runner. The alternative
            # implementation would involve a subprocess, but that adds issues
            # with interrupting subprocesses that are rather complex, so it's
            # simpler just to do it this way.
    finally:
        # restore the original trace function
        sys.settrace(tracer_orig)


@skip_win32
def test_xmode_skip():
    """that xmode skip frames

    Not as a doctest as pytest does not run doctests.
    """
    import pexpect

    env = os.environ.copy()
    env["IPY_TEST_SIMPLE_PROMPT"] = "1"

    child = pexpect.spawn(
        sys.executable, ["-m", "IPython", "--colors=nocolor"], env=env
    )
    child.timeout = 15 * IPYTHON_TESTING_TIMEOUT_SCALE

    child.expect("IPython")
    child.expect("\n")
    child.expect_exact("In [1]")

    block = dedent(
        """
    def f():
        __tracebackhide__ = True
        g()

    def g():
        raise ValueError

    f()
    """
    )

    for line in block.splitlines():
        child.sendline(line)
        child.expect_exact(line)
    child.expect_exact("skipping")

    block = dedent(
        """
    def f():
        __tracebackhide__ = True
        g()

    def g():
        from IPython.core.debugger import set_trace
        set_trace()

    f()
    """
    )

    for line in block.splitlines():
        child.sendline(line)
        child.expect_exact(line)

    child.expect("ipdb>")
    child.sendline("w")
    child.expect("hidden")
    child.expect("ipdb>")
    child.sendline("skip_hidden false")
    child.sendline("w")
    child.expect("__traceba")
    child.expect("ipdb>")

    child.close()


skip_decorators_blocks = (
    """
    def helpers_helper():
        pass # should not stop here except breakpoint
    """,
    """
    def helper_1():
        helpers_helper() # should not stop here
    """,
    """
    def helper_2():
        pass # should not stop here
    """,
    """
    def pdb_skipped_decorator2(function):
        def wrapped_fn(*args, **kwargs):
            __debuggerskip__ = True
            helper_2()
            __debuggerskip__ = False
            result = function(*args, **kwargs)
            __debuggerskip__ = True
            helper_2()
            return result
        return wrapped_fn
    """,
    """
    def pdb_skipped_decorator(function):
        def wrapped_fn(*args, **kwargs):
            __debuggerskip__ = True
            helper_1()
            __debuggerskip__ = False
            result = function(*args, **kwargs)
            __debuggerskip__ = True
            helper_2()
            return result
        return wrapped_fn
    """,
    """
    @pdb_skipped_decorator
    @pdb_skipped_decorator2
    def bar(x, y):
        return x * y
    """,
    """import IPython.terminal.debugger as ipdb""",
    """
    def f():
        ipdb.set_trace()
        bar(3, 4)
    """,
    """
    f()
    """,
)


def _decorator_skip_setup():
    import pexpect

    env = os.environ.copy()
    env["IPY_TEST_SIMPLE_PROMPT"] = "1"
    env["PROMPT_TOOLKIT_NO_CPR"] = "1"

    child = pexpect.spawn(
        sys.executable, ["-m", "IPython", "--colors=nocolor"], env=env
    )
    child.timeout = 15 * IPYTHON_TESTING_TIMEOUT_SCALE

    child.expect("IPython")
    child.expect("\n")

    child.timeout = 5 * IPYTHON_TESTING_TIMEOUT_SCALE
    child.str_last_chars = 500

    dedented_blocks = [dedent(b).strip() for b in skip_decorators_blocks]
    in_prompt_number = 1
    for cblock in dedented_blocks:
        child.expect_exact(f"In [{in_prompt_number}]:")
        in_prompt_number += 1
        for line in cblock.splitlines():
            child.sendline(line)
            child.expect_exact(line)
        child.sendline("")
    return child


@pytest.mark.skip(reason="recently fail for unknown reason on CI")
@skip_win32
def test_decorator_skip():
    """test that decorator frames can be skipped."""

    child = _decorator_skip_setup()

    child.expect_exact("ipython-input-8")
    child.expect_exact("3     bar(3, 4)")
    child.expect("ipdb>")

    child.expect("ipdb>")
    child.sendline("step")
    child.expect_exact("step")
    child.expect_exact("--Call--")
    child.expect_exact("ipython-input-6")

    child.expect_exact("1 @pdb_skipped_decorator")

    child.sendline("s")
    child.expect_exact("return x * y")

    child.close()


@pytest.mark.skip(reason="recently fail for unknown reason on CI")
@pytest.mark.skipif(platform.python_implementation() == "PyPy", reason="issues on PyPy")
@skip_win32
def test_decorator_skip_disabled():
    """test that decorator frame skipping can be disabled"""

    child = _decorator_skip_setup()

    child.expect_exact("3     bar(3, 4)")

    for input_, expected in [
        ("skip_predicates debuggerskip False", ""),
        ("skip_predicates", "debuggerskip : False"),
        ("step", "---> 2     def wrapped_fn"),
        ("step", "----> 3         __debuggerskip__"),
        ("step", "----> 4         helper_1()"),
        ("step", "---> 1 def helper_1():"),
        ("next", "----> 2     helpers_helper()"),
        ("next", "--Return--"),
        ("next", "----> 5         __debuggerskip__ = False"),
    ]:
        child.expect("ipdb>")
        child.sendline(input_)
        child.expect_exact(input_)
        child.expect_exact(expected)

    child.close()


@pytest.mark.skip(reason="recently fail for unknown reason on CI")
@pytest.mark.skipif(platform.python_implementation() == "PyPy", reason="issues on PyPy")
@skip_win32
def test_decorator_skip_with_breakpoint():
    """test that decorator frame skipping can be disabled"""

    import pexpect

    env = os.environ.copy()
    env["IPY_TEST_SIMPLE_PROMPT"] = "1"
    env["PROMPT_TOOLKIT_NO_CPR"] = "1"

    child = pexpect.spawn(
        sys.executable, ["-m", "IPython", "--colors=nocolor"], env=env
    )
    child.timeout = 15 * IPYTHON_TESTING_TIMEOUT_SCALE
    child.str_last_chars = 500

    child.expect("IPython")
    child.expect("\n")

    child.timeout = 5 * IPYTHON_TESTING_TIMEOUT_SCALE

    ### we need a filename, so we need to exec the full block with a filename
    with NamedTemporaryFile(suffix=".py", dir=".", delete=True) as tf:
        name = tf.name[:-3].split("/")[-1]
        tf.write("\n".join([dedent(x) for x in skip_decorators_blocks[:-1]]).encode())
        tf.flush()
        codeblock = f"from {name} import f"

        dedented_blocks = [
            codeblock,
            "f()",
        ]

        in_prompt_number = 1
        for cblock in dedented_blocks:
            child.expect_exact(f"In [{in_prompt_number}]:")
            in_prompt_number += 1
            for line in cblock.splitlines():
                child.sendline(line)
                child.expect_exact(line)
            child.sendline("")

        # From 3.13, set_trace()/breakpoint() stop on the line where they're
        # called, instead of the next line.
        if sys.version_info >= (3, 14):
            child.expect_exact("     46     ipdb.set_trace()")
            extra_step = [("step", "--> 47     bar(3, 4)")]
        elif sys.version_info >= (3, 13):
            child.expect_exact("--> 46     ipdb.set_trace()")
            extra_step = [("step", "--> 47     bar(3, 4)")]
        else:
            child.expect_exact("--> 47     bar(3, 4)")
            extra_step = []

        for input_, expected in (
            [
                (f"b {name}.py:3", ""),
            ]
            + extra_step
            + [
                ("step", "1---> 3     pass # should not stop here except"),
                ("step", "---> 38 @pdb_skipped_decorator"),
                ("continue", ""),
            ]
        ):
            child.expect("ipdb>")
            child.sendline(input_)
            child.expect_exact(input_)
            child.expect_exact(expected)

    child.close()


@skip_win32
def test_where_erase_value():
    """Test that `where` does not access f_locals and erase values."""
    import pexpect

    env = os.environ.copy()
    env["IPY_TEST_SIMPLE_PROMPT"] = "1"

    child = pexpect.spawn(
        sys.executable, ["-m", "IPython", "--colors=nocolor"], env=env
    )
    child.timeout = 15 * IPYTHON_TESTING_TIMEOUT_SCALE

    child.expect("IPython")
    child.expect("\n")
    child.expect_exact("In [1]")

    block = dedent(
        """
    def simple_f():
         myvar = 1
         print(myvar)
         1/0
         print(myvar)
    simple_f()    """
    )

    for line in block.splitlines():
        child.sendline(line)
        child.expect_exact(line)
    child.expect_exact("ZeroDivisionError")
    child.expect_exact("In [2]:")

    child.sendline("%debug")

    ##
    child.expect("ipdb>")

    child.sendline("myvar")
    child.expect("1")

    ##
    child.expect("ipdb>")

    child.sendline("myvar = 2")

    ##
    child.expect_exact("ipdb>")

    child.sendline("myvar")

    child.expect_exact("2")

    ##
    child.expect("ipdb>")
    child.sendline("where")

    ##
    child.expect("ipdb>")
    child.sendline("myvar")

    child.expect_exact("2")
    child.expect("ipdb>")

    child.close()


@skip_win32
def test_ignore_module_basic_functionality():
    """Test basic ignore/unignore functionality and error handling."""
    import pexpect

    env = os.environ.copy()
    env["IPY_TEST_SIMPLE_PROMPT"] = "1"

    with TemporaryDirectory() as temp_dir:
        main_path = create_test_modules(temp_dir)

        child = pexpect.spawn(sys.executable, [main_path], env=env, cwd=temp_dir)
        child.timeout = 15 * IPYTHON_TESTING_TIMEOUT_SCALE
        child.expect("ipdb>")

        # Test listing modules when none are ignored
        child.sendline("ignore_module")
        child.expect_exact("No modules are currently ignored.")
        child.expect("ipdb>")

        # Test ignoring a module
        child.sendline("ignore_module level2_module")
        child.expect("ipdb>")

        # Test listing ignored modules
        child.sendline("ignore_module")
        child.expect_exact("Currently ignored modules: ['level2_module']")
        child.expect("ipdb>")

        # Test wildcard pattern
        child.sendline("ignore_module testpkg.*")
        child.expect("ipdb>")

        child.sendline("ignore_module")
        child.expect_exact("Currently ignored modules: ['level2_module', 'testpkg.*']")
        child.expect("ipdb>")

        # Test error handling - removing non-existent module
        child.sendline("unignore_module nonexistent")
        child.expect_exact("Module nonexistent is not currently ignored")
        child.expect("ipdb>")

        # Test successful removal
        child.sendline("unignore_module level2_module")
        child.expect("ipdb>")

        child.sendline("ignore_module")
        child.expect_exact("Currently ignored modules: ['testpkg.*']")
        child.expect("ipdb>")

        # Test removing already removed module
        child.sendline("unignore_module level2_module")
        child.expect_exact("Module level2_module is not currently ignored")
        child.expect("ipdb>")

        # Remove wildcard pattern
        child.sendline("unignore_module testpkg.*")
        child.expect("ipdb>")

        child.sendline("ignore_module")
        child.expect_exact("No modules are currently ignored.")
        child.expect("ipdb>")

        child.sendline("continue")
        child.close()


# Helper function for creating temporary modules
def create_test_modules(temp_dir):
    """Create a comprehensive module hierarchy for testing all debugger commands."""

    temp_path = Path(temp_dir)

    # Create package structure for wildcard testing
    package_dir = temp_path / "testpkg"
    package_dir.mkdir()

    # Package __init__.py
    (package_dir / "__init__.py").write_text("# Test package")

    # testpkg/submod1.py
    (package_dir / "submod1.py").write_text(
        dedent(
            """
        def submod1_func():
            x = 1
            y = 2
            return x + y
        """
        )
    )

    # testpkg/submod2.py
    (package_dir / "submod2.py").write_text(
        dedent(
            """
        def submod2_func():
            z = 10
            return z * 2
        """
        )
    )

    # Level 1 (top level module)
    (temp_path / "level1_module.py").write_text(
        dedent(
            """
        from level2_module import level2_func

        def level1_func():
            return level2_func()
        """
        )
    )

    # Level 2 (middle level module)
    (temp_path / "level2_module.py").write_text(
        dedent(
            """
        from level3_module import level3_func
        from testpkg.submod1 import submod1_func
        from testpkg.submod2 import submod2_func

        def level2_func():
            # Call package functions for step/next testing
            result1 = submod1_func()
            result2 = submod2_func()
            return level3_func() + result1 + result2
        """
        )
    )

    # Level 3 (bottom level with debugger)
    (temp_path / "level3_module.py").write_text(
        dedent(
            """
        from level4_module import level4_func

        from IPython.core.debugger import set_trace

        def level3_func():
            set_trace()
            pass
            result = level4_func()
            return result
        """
        )
    )

    # Level 4 (bottom level with debugger)
    (temp_path / "level4_module.py").write_text(
        dedent(
            """
        def level4_func():
            a = 70
            b = 30
            return a + b
        """
        )
    )

    # Main runner
    main_path = temp_path / "main_runner.py"
    main_path.write_text(
        dedent(
            """
        import sys
        sys.path.insert(0, '.')
        from level1_module import level1_func

        if __name__ == "__main__":
            result = level1_func()
            print(f"Final result: {result}")
        """
        )
    )

    return str(main_path)


@skip_win32
def test_ignore_module_all_commands():
    """Comprehensive test for all debugger commands (up/down/step/next) with ignore functionality."""
    import pexpect

    env = os.environ.copy()
    env["IPY_TEST_SIMPLE_PROMPT"] = "1"

    with TemporaryDirectory() as temp_dir:
        main_path = create_test_modules(temp_dir)

        # Test UP and DOWN commands
        child = pexpect.spawn(sys.executable, [main_path], env=env, cwd=temp_dir)
        child.timeout = 15 * IPYTHON_TESTING_TIMEOUT_SCALE
        child.expect("ipdb>")

        # Test up without ignores (baseline)
        child.sendline("up")
        child.expect("ipdb>")
        child.sendline("__name__")
        child.expect_exact("level2_module")
        child.expect("ipdb>")

        # Reset position
        child.sendline("down")
        child.expect("ipdb>")

        # Test up with single module ignore
        child.sendline("ignore_module level2_module")
        child.expect("ipdb>")
        child.sendline("up")
        child.expect_exact(
            "[... skipped 1 frame(s): 0 hidden frames + 1 ignored modules]"
        )
        child.expect("ipdb>")
        child.sendline("__name__")
        child.expect_exact("level1_module")
        child.expect("ipdb>")

        # Test up with wildcard ignore
        child.sendline("down")
        child.expect_exact(
            "[... skipped 1 frame(s): 0 hidden frames + 1 ignored modules]"
        )
        child.expect("ipdb>")
        child.sendline("unignore_module level2_module")
        child.expect("ipdb>")
        child.sendline("ignore_module level*")
        child.expect("ipdb>")
        child.sendline("up")
        child.expect_exact(
            "[... skipped 2 frame(s): 0 hidden frames + 2 ignored modules]"
        )
        child.expect("ipdb>")
        child.sendline("__name__")
        child.expect_exact("__main__")
        child.expect("ipdb>")

        child.sendline("continue")
        child.close()

        # Test STEP command
        child = pexpect.spawn(sys.executable, [main_path], env=env, cwd=temp_dir)
        child.timeout = 15 * IPYTHON_TESTING_TIMEOUT_SCALE
        child.expect("ipdb>")

        # Test step without ignores (should step into module)
        child.sendline("until 9")
        child.expect("ipdb>")
        child.sendline("step")
        child.expect("ipdb>")
        child.sendline("__name__")
        child.expect_exact("level4_module")
        child.expect("ipdb>")

        child.sendline("continue")
        child.close()

        # Test step with single module ignore
        child = pexpect.spawn(sys.executable, [main_path], env=env, cwd=temp_dir)
        child.timeout = 15 * IPYTHON_TESTING_TIMEOUT_SCALE
        child.expect("ipdb>")

        child.sendline("ignore_module level4_module")
        child.expect("ipdb>")
        child.sendline("until 9")
        child.expect("ipdb>")
        child.sendline("step")
        child.expect_exact("[... skipped 1 ignored module(s)]")
        child.expect("ipdb>")
        child.sendline("__name__")
        child.expect_exact("level3_module")
        child.expect("ipdb>")

        child.sendline("continue")
        child.close()

        # Test NEXT command
        child = pexpect.spawn(sys.executable, [main_path], env=env, cwd=temp_dir)
        child.timeout = 15 * IPYTHON_TESTING_TIMEOUT_SCALE
        child.expect("ipdb>")

        # Test next without ignores
        child.sendline("until 9")
        child.expect("ipdb>")
        child.sendline("next")
        child.expect("ipdb>")
        child.sendline("__name__")
        child.expect_exact("level3_module")
        child.expect("ipdb>")

        child.sendline("continue")
        child.close()

        # Test next with module ignore
        child = pexpect.spawn(sys.executable, [main_path], env=env, cwd=temp_dir)
        child.timeout = 15 * IPYTHON_TESTING_TIMEOUT_SCALE
        child.expect("ipdb>")

        child.sendline("ignore_module level2_module")
        child.expect("ipdb>")
        child.sendline("return")
        child.expect("ipdb>")
        child.sendline("next")
        child.expect_exact("[... skipped 1 ignored module(s)]")
        child.expect("ipdb>")

        child.sendline("continue")
        child.close()