# Licensed under the GPL: https://www.gnu.org/licenses/old-licenses/gpl-2.0.html
# For details: https://github.com/pylint-dev/pylint/blob/main/LICENSE
# Copyright (c) https://github.com/pylint-dev/pylint/blob/main/CONTRIBUTORS.txt

from __future__ import annotations

import codecs
import os
import re
import sys
import textwrap
import tokenize
import warnings
from collections import deque
from collections.abc import Iterable, Sequence
from io import BufferedReader, BytesIO
from re import Pattern
from typing import TYPE_CHECKING, Any, Literal, TextIO, TypeVar

from astroid import modutils, nodes

from pylint.constants import PY_EXTS
from pylint.typing import OptionDict

if TYPE_CHECKING:
    from pylint.lint import PyLinter

DEFAULT_LINE_LENGTH = 79

# These are types used to overload get_global_option() and refer to the options type
GLOBAL_OPTION_BOOL = Literal[
    "analyse-fallback-blocks",
    "allow-global-unused-variables",
    "prefer-stubs",
]
GLOBAL_OPTION_INT = Literal["max-line-length", "docstring-min-length"]
GLOBAL_OPTION_LIST = Literal["ignored-modules"]
GLOBAL_OPTION_PATTERN = Literal[
    "no-docstring-rgx",
    "dummy-variables-rgx",
    "ignored-argument-names",
    "mixin-class-rgx",
]
GLOBAL_OPTION_PATTERN_LIST = Literal["exclude-too-few-public-methods", "ignore-paths"]
GLOBAL_OPTION_TUPLE_INT = Literal["py-version"]
GLOBAL_OPTION_NAMES = (
    GLOBAL_OPTION_BOOL
    | GLOBAL_OPTION_INT
    | GLOBAL_OPTION_LIST
    | GLOBAL_OPTION_PATTERN
    | GLOBAL_OPTION_PATTERN_LIST
    | GLOBAL_OPTION_TUPLE_INT
)
T_GlobalOptionReturnTypes = TypeVar(
    "T_GlobalOptionReturnTypes",
    bool,
    int,
    list[str],
    Pattern[str],
    list[Pattern[str]],
    tuple[int, ...],
)


def normalize_text(
    text: str, line_len: int = DEFAULT_LINE_LENGTH, indent: str = ""
) -> str:
    """Wrap the text on the given line length."""
    return "\n".join(
        textwrap.wrap(
            text, width=line_len, initial_indent=indent, subsequent_indent=indent
        )
    )


CMPS = ["=", "-", "+"]


# py3k has no more cmp builtin
def cmp(a: float, b: float) -> int:
    return (a > b) - (a < b)


def diff_string(old: float, new: float) -> str:
    """Given an old and new value, return a string representing the difference."""
    diff = abs(old - new)
    diff_str = f"{CMPS[cmp(old, new)]}{(diff and f'{diff:.2f}') or ''}"
    return diff_str


def get_module_and_frameid(node: nodes.NodeNG) -> tuple[str, str]:
    """Return the module name and the frame id in the module."""
    frame = node.frame()
    module, obj = "", []
    while frame:
        if isinstance(frame, nodes.Module):
            module = frame.name
        else:
            obj.append(getattr(frame, "name", "<lambda>"))
        try:
            frame = frame.parent.frame()
        except AttributeError:
            break
    return module, ".".join(reversed(obj))


def get_rst_title(title: str, character: str) -> str:
    """Permit to get a title formatted as ReStructuredText test (underlined with a
    chosen character).
    """
    return f"{title}\n{character * len(title)}\n"


def get_rst_section(
    section: str | None,
    options: list[tuple[str, OptionDict, Any]],
    doc: str | None = None,
) -> str:
    """Format an option's section using as a ReStructuredText formatted output."""
    result = ""
    if section:
        result += get_rst_title(section, "'")
    if doc:
        formatted_doc = normalize_text(doc)
        result += f"{formatted_doc}\n\n"
    for optname, optdict, value in options:
        help_opt = optdict.get("help")
        result += f":{optname}:\n"
        if help_opt:
            assert isinstance(help_opt, str)
            formatted_help = normalize_text(help_opt, indent="  ")
            result += f"{formatted_help}\n"
        if value and optname != "py-version":
            value = str(_format_option_value(optdict, value))
            result += f"\n  Default: ``{value.replace('`` ', '```` ``')}``\n"
    return result


def decoding_stream(
    stream: BufferedReader | BytesIO,
    encoding: str,
    errors: Literal["strict"] = "strict",
) -> codecs.StreamReader:
    try:
        reader_cls = codecs.getreader(encoding or sys.getdefaultencoding())
    except LookupError:
        reader_cls = codecs.getreader(sys.getdefaultencoding())
    return reader_cls(stream, errors)


def tokenize_module(node: nodes.Module) -> list[tokenize.TokenInfo]:
    with node.stream() as stream:
        readline = stream.readline
        return list(tokenize.tokenize(readline))


def register_plugins(linter: PyLinter, directory: str) -> None:
    """Load all module and package in the given directory, looking for a
    'register' function in each one, used to register pylint checkers.
    """
    imported = {}
    for filename in os.listdir(directory):
        base, extension = os.path.splitext(filename)
        if base in imported or base == "__pycache__":
            continue
        if (extension in PY_EXTS and base != "__init__") or (
            not extension
            and os.path.isdir(os.path.join(directory, base))
            and not filename.startswith(".")
        ):
            try:
                module = modutils.load_module_from_file(
                    os.path.join(directory, filename)
                )
            except ValueError:
                # empty module name (usually Emacs auto-save files)
                continue
            except ImportError as exc:
                print(f"Problem importing module {filename}: {exc}", file=sys.stderr)
            else:
                if hasattr(module, "register"):
                    module.register(linter)
                    imported[base] = 1


def _splitstrip(string: str, sep: str = ",") -> list[str]:
    r"""Return a list of stripped string by splitting the string given as
    argument on `sep` (',' by default), empty strings are discarded.

    >>> _splitstrip('a, b, c   ,  4,,')
    ['a', 'b', 'c', '4']
    >>> _splitstrip('a')
    ['a']
    >>> _splitstrip('a,\nb,\nc,')
    ['a', 'b', 'c']

    :type string: str or unicode
    :param string: a csv line

    :type sep: str or unicode
    :param sep: field separator, default to the comma (',')

    :rtype: str or unicode
    :return: the unquoted string (or the input string if it wasn't quoted)
    """
    return [word.strip() for word in string.split(sep) if word.strip()]


def _unquote(string: str) -> str:
    """Remove optional quotes (simple or double) from the string.

    :param string: an optionally quoted string
    :return: the unquoted string (or the input string if it wasn't quoted)
    """
    if not string:
        return string
    if string[0] in "\"'":
        string = string[1:]
    if string[-1] in "\"'":
        string = string[:-1]
    return string


def _check_csv(value: list[str] | tuple[str] | str) -> Sequence[str]:
    if isinstance(value, (list, tuple)):
        return value
    return _splitstrip(value)


def _check_regexp_csv(value: list[str] | tuple[str] | str) -> Iterable[str]:
    r"""Split a comma-separated list of regexps, taking care to avoid splitting
    a regex employing a comma as quantifier, as in `\d{1,2}`.
    """
    if isinstance(value, (list, tuple)):
        yield from value
    else:
        # None is a sentinel value here
        regexps: deque[deque[str] | None] = deque([None])
        open_braces = False
        for char in value:
            if char == "{":
                open_braces = True
            elif char == "}" and open_braces:
                open_braces = False

            if char == "," and not open_braces:
                regexps.append(None)
            elif regexps[-1] is None:
                regexps.pop()
                regexps.append(deque([char]))
            else:
                regexps[-1].append(char)
        yield from ("".join(regexp).strip() for regexp in regexps if regexp is not None)


def _comment(string: str) -> str:
    """Return string as a comment."""
    lines = [line.strip() for line in string.splitlines()]
    sep = "\n"
    return "# " + f"{sep}# ".join(lines)


def _format_option_value(optdict: OptionDict, value: Any) -> str:
    """Return the user input's value from a 'compiled' value.

    TODO: Refactor the code to not use this deprecated function
    """
    if optdict.get("type", None) == "py_version":
        value = ".".join(str(item) for item in value)
    elif isinstance(value, (list, tuple)):
        value = ",".join(_format_option_value(optdict, item) for item in value)
    elif isinstance(value, dict):
        value = ",".join(f"{k}:{v}" for k, v in value.items())
    elif hasattr(value, "match"):  # optdict.get('type') == 'regexp'
        # compiled regexp
        value = value.pattern
    elif optdict.get("type") == "yn":
        value = "yes" if value else "no"
    elif isinstance(value, str) and value.isspace():
        value = f"'{value}'"
    return str(value)


def format_section(
    stream: TextIO,
    section: str,
    options: list[tuple[str, OptionDict, Any]],
    doc: str | None = None,
) -> None:
    """Format an option's section using the INI format."""
    warnings.warn(
        "format_section has been deprecated. It will be removed in pylint 4.0.",
        DeprecationWarning,
        stacklevel=2,
    )
    if doc:
        print(_comment(doc), file=stream)
    print(f"[{section}]", file=stream)
    with warnings.catch_warnings():
        warnings.filterwarnings("ignore", category=DeprecationWarning)
        _ini_format(stream, options)


def _ini_format(stream: TextIO, options: list[tuple[str, OptionDict, Any]]) -> None:
    """Format options using the INI format."""
    warnings.warn(
        "_ini_format has been deprecated. It will be removed in pylint 4.0.",
        DeprecationWarning,
        stacklevel=2,
    )
    for optname, optdict, value in options:
        # Skip deprecated option
        if "kwargs" in optdict:
            assert isinstance(optdict["kwargs"], dict)
            if "new_names" in optdict["kwargs"]:
                continue
        value = _format_option_value(optdict, value)
        help_opt = optdict.get("help")
        if help_opt:
            assert isinstance(help_opt, str)
            help_opt = normalize_text(help_opt, indent="# ")
            print(file=stream)
            print(help_opt, file=stream)
        else:
            print(file=stream)
        if value in {"None", "False"}:
            print(f"#{optname}=", file=stream)
        else:
            value = str(value).strip()
            if re.match(r"^([\w-]+,)+[\w-]+$", str(value)):
                separator = "\n " + " " * len(optname)
                value = separator.join(x + "," for x in str(value).split(","))
                # remove trailing ',' from last element of the list
                value = value[:-1]
            print(f"{optname}={value}", file=stream)
