From 766cba186e6f396e6ade4f3c5efeab42a978744a Mon Sep 17 00:00:00 2001
From: Ghost Ops <72981180+GhostOps77@users.noreply.github.com>
Date: Wed, 1 May 2024 17:21:12 +0530
Subject: [PATCH 1/4] implement repl context class

---
 click_repl/__init__.py   |   1 +
 click_repl/_ctx_stack.py |  28 +++++
 click_repl/_repl.py      |  96 ++++++++++--------
 click_repl/core.py       | 213 +++++++++++++++++++++++++++++++++++++++
 click_repl/globals_.py   |  46 +++++++++
 5 files changed, 341 insertions(+), 43 deletions(-)
 create mode 100644 click_repl/_ctx_stack.py
 create mode 100644 click_repl/core.py
 create mode 100644 click_repl/globals_.py

diff --git a/click_repl/__init__.py b/click_repl/__init__.py
index df3cea8..425c447 100644
--- a/click_repl/__init__.py
+++ b/click_repl/__init__.py
@@ -7,5 +7,6 @@
     InternalCommandException as InternalCommandException,
 )
 from .utils import exit as exit  # noqa: F401
+from .core import pass_context as pass_context
 
 __version__ = "0.3.0"
diff --git a/click_repl/_ctx_stack.py b/click_repl/_ctx_stack.py
new file mode 100644
index 0000000..1046ccd
--- /dev/null
+++ b/click_repl/_ctx_stack.py
@@ -0,0 +1,28 @@
+from __future__ import annotations
+
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from .core import ReplContext
+
+
+# To store the ReplContext objects generated throughout the Runtime.
+_context_stack: list[ReplContext] = []
+
+
+def _push_context(ctx: ReplContext) -> None:
+    """
+    Pushes a new REPL context onto the current stack.
+
+    Parameters
+    ----------
+    ctx
+        The :class:`~click_repl.core.ReplContext` object that should be
+        added to the REPL context stack.
+    """
+    _context_stack.append(ctx)
+
+
+def _pop_context() -> None:
+    """Removes the top-level REPL context from the stack."""
+    _context_stack.pop()
diff --git a/click_repl/_repl.py b/click_repl/_repl.py
index 5693f52..d3ae9ff 100644
--- a/click_repl/_repl.py
+++ b/click_repl/_repl.py
@@ -2,13 +2,14 @@
 
 import click
 import sys
-from prompt_toolkit import PromptSession
 from prompt_toolkit.history import InMemoryHistory
 
 from ._completer import ClickCompleter
 from .exceptions import ClickExit  # type: ignore[attr-defined]
 from .exceptions import CommandLineParserError, ExitReplException, InvalidGroupFormat
 from .utils import _execute_internal_and_sys_cmds
+from .core import ReplContext
+from .globals_ import ISATTY, get_current_repl_ctx
 
 
 __all__ = ["bootstrap_prompt", "register_repl", "repl"]
@@ -90,58 +91,67 @@ def repl(
 
     original_command = available_commands.pop(repl_command_name, None)
 
-    if isatty:
-        prompt_kwargs = bootstrap_prompt(group, prompt_kwargs, group_ctx)
-        session = PromptSession(**prompt_kwargs)
+    repl_ctx = ReplContext(
+        group_ctx,
+        bootstrap_prompt(group, prompt_kwargs, group_ctx),
+        get_current_repl_ctx(silent=True)
+    )
 
-        def get_command():
-            return session.prompt()
+    if ISATTY:
+        # If stdin is a TTY, prompt the user for input using PromptSession.
+        def get_command() -> str:
+            return repl_ctx.session.prompt()  # type: ignore
 
     else:
-        get_command = sys.stdin.readline
-
-    while True:
-        try:
-            command = get_command()
-        except KeyboardInterrupt:
-            continue
-        except EOFError:
-            break
-
-        if not command:
-            if isatty:
+        # If stdin is not a TTY, read input from stdin directly.
+        def get_command() -> str:
+            inp = sys.stdin.readline().strip()
+            repl_ctx._history.append(inp)
+            return inp
+
+    with repl_ctx:
+        while True:
+            try:
+                command = get_command()
+            except KeyboardInterrupt:
                 continue
-            else:
+            except EOFError:
                 break
 
-        try:
-            args = _execute_internal_and_sys_cmds(
-                command, allow_internal_commands, allow_system_commands
-            )
-            if args is None:
-                continue
+            if not command:
+                if isatty:
+                    continue
+                else:
+                    break
+
+            try:
+                args = _execute_internal_and_sys_cmds(
+                    command, allow_internal_commands, allow_system_commands
+                )
+                if args is None:
+                    continue
 
-        except CommandLineParserError:
-            continue
+            except CommandLineParserError:
+                continue
 
-        except ExitReplException:
-            break
+            except ExitReplException:
+                break
 
-        try:
-            # The group command will dispatch based on args.
-            old_protected_args = group_ctx.protected_args
             try:
-                group_ctx.protected_args = args
-                group.invoke(group_ctx)
-            finally:
-                group_ctx.protected_args = old_protected_args
-        except click.ClickException as e:
-            e.show()
-        except (ClickExit, SystemExit):
-            pass
-
-        except ExitReplException:
-            break
+                # The group command will dispatch based on args.
+                old_protected_args = group_ctx.protected_args
+                try:
+                    group_ctx.protected_args = args
+                    group.invoke(group_ctx)
+                finally:
+                    group_ctx.protected_args = old_protected_args
+            except click.ClickException as e:
+                e.show()
+            except (ClickExit, SystemExit):
+                pass
+
+            except ExitReplException:
+                break
 
     if original_command is not None:
         available_commands[repl_command_name] = original_command
diff --git a/click_repl/core.py b/click_repl/core.py
new file mode 100644
index 0000000..3c81031
--- /dev/null
+++ b/click_repl/core.py
@@ -0,0 +1,213 @@
+"""
+Core functionalities for managing context of the click_repl app.
+"""
+
+from __future__ import annotations
+
+from functools import wraps
+from typing import TYPE_CHECKING, Any, Callable, Dict, Generator, TypeVar
+
+from click import Context
+from prompt_toolkit import PromptSession
+from typing_extensions import Concatenate, Final, ParamSpec, TypeAlias, TypedDict
+
+from ._ctx_stack import _pop_context, _push_context
+from .globals_ import ISATTY, get_current_repl_ctx
+
+if TYPE_CHECKING:
+    from prompt_toolkit.formatted_text import AnyFormattedText
+
+
+P = ParamSpec("P")
+R = TypeVar("R")
+F = TypeVar("F", bound=Callable[..., Any])
+
+
+__all__ = ["ReplContext", "pass_context"]
+
+
+_PromptSession: TypeAlias = PromptSession[Dict[str, Any]]
+
+
+class ReplContextInfoDict(TypedDict):
+    group_ctx: Context
+    prompt_kwargs: dict[str, Any]
+    session: _PromptSession | None
+    parent: ReplContext | None
+    _history: list[str]
+
+
+class ReplContext:
+    """
+    Context object for the REPL sessions.
+
+    This class tracks the depth of nested REPLs, ensuring seamless navigation
+    between different levels. It facilitates nested REPL scenarios, allowing
+    multiple levels of interactive REPL sessions.
+
+    Each REPL's properties are stored inside this context class, allowing them to
+    be accessed and shared with their parent REPL.
+
+    All the settings for each REPL session persist until the session is terminated.
+
+    Parameters
+    ----------
+    group_ctx
+        The click context object that belong to the CLI/parent Group.
+
+    prompt_kwargs
+        Extra keyword arguments for :class:`~prompt_toolkit.shortcuts.PromptSession` class.
+
+    parent
+        REPL Context object of the parent REPL session, if exists. Otherwise, :obj:`None`.
+    """
+
+    __slots__ = (
+        "group_ctx",
+        "prompt_kwargs",
+        "parent",
+        "session",
+        "_history",
+    )
+
+    def __init__(
+        self,
+        group_ctx: Context,
+        prompt_kwargs: dict[str, Any] = {},
+        parent: ReplContext | None = None,
+    ) -> None:
+        """
+        Initializes the `ReplContext` class.
+        """
+        session: _PromptSession | None
+
+        if ISATTY:
+            session = PromptSession(**prompt_kwargs)
+
+        else:
+            session = None
+
+        self.group_ctx: Final[Context] = group_ctx
+        """The click context object that belong to the CLI/parent Group."""
+
+        self.session = session
+        """Object that's responsible for managing and executing the REPL."""
+
+        self._history: list[str] = []
+        """
+        History of past executed commands.
+
+        Used only when :func:`~sys.stdin.isatty` is :obj:`False`.
+        """
+
+        self.prompt_kwargs = prompt_kwargs
+        """
+        Extra keyword arguments for
+        :class:`~prompt_toolkit.shortcuts.PromptSession` class.
+        """
+
+        self.parent: Final[ReplContext | None] = parent
+        """
+        REPL Context object of the parent REPL session, if exists.
+        Otherwise, :obj:`None`.
+        """
+
+    def __enter__(self) -> ReplContext:
+        _push_context(self)
+        return self
+
+    def __exit__(self, *_: Any) -> None:
+        _pop_context()
+
+    @property
+    def prompt(self) -> AnyFormattedText:
+        """
+        The prompt text of the REPL.
+
+        Returns
+        -------
+        prompt_toolkit.formatted_text.AnyFormattedText
+            The prompt object if :func:`~sys.stdin.isatty` is :obj:`True`,
+            else :obj:`None`.
+        """
+        if ISATTY and self.session is not None:
+            return self.session.message
+        return None
+
+    @prompt.setter
+    def prompt(self, value: AnyFormattedText) -> None:
+        if ISATTY and self.session is not None:
+            self.session.message = value
+
+    def to_info_dict(self) -> ReplContextInfoDict:
+        """
+        Provides a dictionary with minimal info about the current REPL.
+
+        Returns
+        -------
+        ReplContextInfoDict
+            A dictionary that has the instance variables and their values.
+        """
+
+        res: ReplContextInfoDict = {
+            "group_ctx": self.group_ctx,
+            "prompt_kwargs": self.prompt_kwargs,
+            "session": self.session,
+            "parent": self.parent,
+            "_history": self._history,
+        }
+
+        return res
+
+    def session_reset(self) -> None:
+        """
+        Resets values of :class:`~prompt_toolkit.session.PromptSession` to
+        the provided :attr:`~.prompt_kwargs`, discarding any changes done to the
+        :class:`~prompt_toolkit.session.PromptSession` object.
+        """
+
+        if ISATTY and self.session is not None:
+            self.session = PromptSession(**self.prompt_kwargs)
+
+    def history(self) -> Generator[str, None, None]:
+        """
+        Generates the history of past executed commands.
+
+        Yields
+        ------
+        str
+            The executed command string from the history,
+            in chronological order from most recent to oldest.
+        """
+
+        if ISATTY and self.session is not None:
+            yield from self.session.history.load_history_strings()
+
+        else:
+            yield from reversed(self._history)
+
+
+def pass_context(
+    func: Callable[Concatenate[ReplContext | None, P], R],
+) -> Callable[P, R]:
+    """
+    Decorator that marks a callback function to receive the current
+    REPL context object as its first argument.
+
+    Parameters
+    ----------
+    func
+        The callback function to pass context as its first parameter.
+
+    Returns
+    -------
+    Callable[P,R]
+        The decorated callback function that receives the current REPL
+        context object as its first argument.
+    """
+
+    @wraps(func)
+    def decorator(*args: P.args, **kwargs: P.kwargs) -> R:
+        return func(get_current_repl_ctx(), *args, **kwargs)
+
+    return decorator
diff --git a/click_repl/globals_.py b/click_repl/globals_.py
new file mode 100644
index 0000000..d009d3b
--- /dev/null
+++ b/click_repl/globals_.py
@@ -0,0 +1,46 @@
+from __future__ import annotations
+
+import sys
+from typing import TYPE_CHECKING, NoReturn
+
+from ._ctx_stack import _context_stack
+
+if TYPE_CHECKING:
+    from .core import ReplContext
+
+
+ISATTY = sys.stdin.isatty()
+
+
+def get_current_repl_ctx(silent: bool = False) -> ReplContext | NoReturn | None:
+    """
+    Retrieves the current click-repl context.
+
+    This function provides a way to access the context from anywhere
+    in the code. This function serves as a more implicit alternative to the
+    :func:`~click.core.pass_context` decorator.
+
+    Parameters
+    ----------
+    silent
+        If set to :obj:`True`, the function returns :obj:`None` if no context
+        is available. The default behavior is to raise a :exc:`~RuntimeError`.
+
+    Returns
+    -------
+    :class:`~click_repl.core.ReplContext` | None
+        REPL context object if available, or :obj:`None` if ``silent`` is :obj:`True`.
+
+    Raises
+    ------
+    RuntimeError
+        If there's no context object in the stack and ``silent`` is :obj:`False`.
+    """
+
+    try:
+        return _context_stack[-1]
+    except (AttributeError, IndexError):
+        if not silent:
+            raise RuntimeError("There is no active click-repl context.")
+
+    return None

From 244405117e34b5cede1d9d17b5f5100efde981cf Mon Sep 17 00:00:00 2001
From: Ghost Ops <72981180+GhostOps77@users.noreply.github.com>
Date: Wed, 1 May 2024 17:25:35 +0530
Subject: [PATCH 2/4] added tests

---
 tests/test_repl_ctx.py | 65 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 65 insertions(+)
 create mode 100644 tests/test_repl_ctx.py

diff --git a/tests/test_repl_ctx.py b/tests/test_repl_ctx.py
new file mode 100644
index 0000000..8613d25
--- /dev/null
+++ b/tests/test_repl_ctx.py
@@ -0,0 +1,65 @@
+from __future__ import annotations
+
+import click
+import pytest
+
+import click_repl
+from click_repl.core import ReplContext
+from tests import mock_stdin
+
+
+@click.group(invoke_without_command=True)
+@click.pass_context
+def cli(ctx):
+    if ctx.invoked_subcommand is None:
+        click_repl.repl(ctx)
+
+
+@cli.command()
+def hello():
+    print("Hello!")
+
+
+@cli.command()
+@click_repl.pass_context
+def history_test(repl_ctx):
+    print(list(repl_ctx.history()))
+
+
+def test_repl_ctx_history(capsys):
+    with mock_stdin("hello\nhistory-test\n"):
+        with pytest.raises(SystemExit):
+            cli(args=[], prog_name="test_repl_ctx_history")
+
+    assert (
+        capsys.readouterr().out.replace("\r\n", "\n")
+        == "Hello!\n['history-test', 'hello']\n"
+    )
+
+
+@cli.command()
+@click_repl.pass_context
+def prompt_test(repl_ctx):
+    print(repl_ctx.prompt)
+
+
+def test_repl_ctx_prompt(capsys):
+    with mock_stdin("prompt-test\n"):
+        with pytest.raises(SystemExit):
+            cli(args=[], prog_name="test_repl_ctx_history")
+
+    assert capsys.readouterr().out.replace("\r\n", "\n") == "None\n"
+
+
+def test_repl_ctx_info_dict():
+    repl_ctx = ReplContext(
+        click.Context(click.Command(test_repl_ctx_info_dict))
+    )
+
+    assert repl_ctx.to_info_dict() == {
+        "group_ctx": repl_ctx.group_ctx,
+        "prompt_kwargs": repl_ctx.prompt_kwargs,
+        "session": repl_ctx.session,
+        "parent": repl_ctx.parent,
+        "_history": repl_ctx._history,
+    }

From 70994ec52650172967fa04103b115ff86e6d83e5 Mon Sep 17 00:00:00 2001
From: Ghost Ops <72981180+GhostOps77@users.noreply.github.com>
Date: Wed, 1 May 2024 17:26:30 +0530
Subject: [PATCH 3/4] updated dependencies

---
 setup.cfg | 1 +
 1 file changed, 1 insertion(+)

diff --git a/setup.cfg b/setup.cfg
index 7cba7f5..b8b3a2d 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -29,6 +29,7 @@ packages=
 install_requires =
   click>=7.0
   prompt_toolkit>=3.0.36
+  typing-extensions>=4.7.0
 
 python_requires = >=3.6
 zip_safe = no

From 718dd0a862689f2ab5f3646afce5fbf4f09b4c66 Mon Sep 17 00:00:00 2001
From: Ghost Ops <72981180+GhostOps77@users.noreply.github.com>
Date: Wed, 1 May 2024 17:28:48 +0530
Subject: [PATCH 4/4] fixed flake8 errors

---
 click_repl/__init__.py | 2 +-
 click_repl/core.py     | 3 ++-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/click_repl/__init__.py b/click_repl/__init__.py
index 425c447..139d939 100644
--- a/click_repl/__init__.py
+++ b/click_repl/__init__.py
@@ -7,6 +7,6 @@
     InternalCommandException as InternalCommandException,
 )
 from .utils import exit as exit  # noqa: F401
-from .core import pass_context as pass_context
+from .core import pass_context as pass_context  # noqa: F401
 
 __version__ = "0.3.0"
diff --git a/click_repl/core.py b/click_repl/core.py
index 3c81031..79d30fa 100644
--- a/click_repl/core.py
+++ b/click_repl/core.py
@@ -56,7 +56,8 @@ class ReplContext:
         The click context object that belong to the CLI/parent Group.
 
     prompt_kwargs
-        Extra keyword arguments for :class:`~prompt_toolkit.shortcuts.PromptSession` class.
+        Extra keyword arguments for
+        :class:`~prompt_toolkit.shortcuts.PromptSession` class.
 
     parent
         REPL Context object of the parent REPL session, if exists. Otherwise, :obj:`None`.