path: root/duplicate_finder/cli.py

# SPDX-FileCopyrightText: 2026 Dennis Fink <me+coding@dennisfink.me>
#
# SPDX-License-Identifier: BSD-3-Clause

"""Define Click parameter types and styled terminal message helpers."""

import re
from collections.abc import Callable
from functools import update_wrapper
from typing import Any, Concatenate

import click_extra as click
from click_extra.color import ColorOption

_SIZE_RE = re.compile(
    r"^\s*(?P<value>\d+\.?\d*)\s*((?P<unit>[kmgtpe]i?)?)b?\s*$", re.IGNORECASE
)
_SIZE_MULTIPLIERS = {
    "": 1,
    "k": 1000,
    "ki": 1024,
    "m": 1000**2,
    "mi": 1024**2,
    "g": 1000**3,
    "gi": 1024**3,
    "t": 1000**4,
    "ti": 1024**4,
    "p": 1000**5,
    "pi": 1024**5,
    "e": 1000**6,
    "ei": 1024**6,
}


class ByteSizeParamType(click.ParamType):
    """Parse byte sizes with optional decimal or binary unit suffixes."""

    name = "size"

    def convert(
        self, value: Any, param: click.Parameter | None, ctx: click.Context | None
    ) -> int:
        """Convert a Click parameter value to a size in bytes.

        :param value: Value supplied by Click.
        :param param: Parameter currently being converted, if available.
        :param ctx: Active Click context, if available.
        :returns: The parsed size in bytes.
        :raises click.BadParameter: If the value is negative, has an unsupported type,
            or cannot be parsed as a byte size.
        """
        if isinstance(value, int):
            if value < 0:
                self.fail("Size must be non-negative.", param, ctx)
            return value

        if not isinstance(value, str):
            self.fail("Size must be a string like '10M' or an integer.", param, ctx)

        if (match := _SIZE_RE.match(value)) is not None:
            groups = match.groupdict()
            return round(
                float(groups["value"]) * _SIZE_MULTIPLIERS[groups["unit"].lower()]
            )
        else:
            self.fail(f"Invalid size: {value!r}", param, ctx)


class FlexibleColorOption(ColorOption):
    """Allow the color option value to be passed with or without ``=``."""

    _gnu_optional_value = False


def pass_obj_silent[T, **P, R](
    f: Callable[Concatenate[T | None, P], R],
) -> Callable[P, R]:
    """Pass the current context object to a callback, if available.

    The current Click context is retrieved silently. If no context exists or
    its object is not a dictionary, ``None`` is passed instead.

    The context object is inserted as the first positional argument to *f*.
    """

    def new_func(*args: P.args, **kwargs: P.kwargs) -> R:
        ctx = click.get_current_context(silent=True)
        obj = ctx.obj if ctx is not None else None
        return f(obj, *args, **kwargs)

    return update_wrapper(new_func, f)


def emit(
    prefix: str, color: str, *message: str, enabled: bool = True, err: bool = False
) -> None:
    """Render a styled prefix and message to stdout.

    This helper is used by :func:`error`, :func:`msg`, :func:`warn`,
    :func:`verbose`, and :func:`debug`. The first message argument is rendered in
    bold and subsequent arguments are appended unstyled.

    :param prefix: Prefix displayed before the message.
    :param color: Click-compatible color name applied to the prefix.
    :param message: One or more message parts to display.
    :param enabled: Whether the message should be emitted.
    :param err: Write to `stderr` instead of `stdout`.
    :raises TypeError: If no message arguments are provided.
    """
    if not message:
        raise TypeError("emit() missing 1 required positional argument: 'message'")

    if not enabled:
        return

    click.echo(
        " ".join(
            [
                click.style(prefix, fg=color, bold=True),
                click.style(message[0], bold=True),
                *message[1:],
            ]
        ),
        err=err,
    )


def error(*message: str) -> None:
    """Print a formatted error message to stdout in red.

    The first argument is rendered in bold and subsequent arguments are appended
    unstyled. Error messages are always printed regardless of quiet or verbose
    flags.

    :param message: One or more message parts to display.
    """
    emit("==> ERROR:", "red", *message, err=True)


@pass_obj_silent
def msg(obj: dict[str, Any] | None, *message: str, err: bool = False) -> None:
    """Print a formatted informational message to stdout in green.

    The message is suppressed when the quiet flag is set. When called outside a
    Click context, the message is emitted normally. The first argument is rendered
    in bold and subsequent arguments are appended unstyled.

    :param message: One or more message parts to display.
    """
    emit(
        "==>",
        "green",
        *message,
        enabled=obj is None or not obj.get("quiet", False),
        err=err,
    )


@pass_obj_silent
def warn(obj: dict[str, Any] | None, *message: str, err: bool = False) -> None:
    """Print a formatted warning message to stdout in yellow.

    The message is suppressed when the quiet flag is set. When called outside a
    Click context, the message is emitted normally. The first argument is rendered
    in bold and subsequent arguments are appended unstyled.

    :param message: One or more message parts to display.
    """
    emit(
        "==>",
        "yellow",
        *message,
        enabled=obj is None or not obj.get("quiet", False),
        err=err,
    )


@pass_obj_silent
def verbose(obj: dict[str, Any] | None, *message: str, err: bool = False) -> None:
    """Print a formatted verbose message to stdout in blue.

    The message is printed only when called from a Click context with the verbose
    flag set and the quiet flag unset. Calls made outside a Click context are a
    no-op.

    :param message: One or more message parts to display.
    """
    emit(
        "==>",
        "blue",
        *message,
        enabled=(
            obj is not None
            and obj.get("verbose", False)
            and not obj.get("quiet", False)
        ),
        err=err,
    )


@pass_obj_silent
def debug(obj: dict[str, Any] | None, *message: str, err: bool = False) -> None:
    """Print a formatted debug message to stdout in magenta.

    The message is printed only when called from a Click context with the debug
    flag enabled. Calls made outside a Click context are a no-op.

    :param message: One or more message parts to display.
    """
    emit(
        "==>",
        "magenta",
        *message,
        enabled=obj is not None and obj.get("debug", False),
        err=err,
    )


@pass_obj_silent
def is_debug_enabled(obj: dict[str, Any] | None) -> bool:
    """Return whether debug output is enabled for the active Click context.

    :returns: ``True`` when a Click context exists and its debug flag is enabled.
    """
    return obj is not None and obj.get("debug", False)


@pass_obj_silent
def is_quiet_enabled(obj: dict[str, Any] | None) -> bool:
    """Return whether quiet output is enabled for the active Click context.

    :returns: ``True`` when a Click context exists and its quiet flag is enabled.
    """
    return obj is not None and obj.get("quiet", False)