# -*- coding: utf-8 -*-
# This code is part of the Ansible collection community.docker, but is an independent component.
# This particular file, and this file only, is based on the Docker SDK for Python (https://github.com/docker/docker-py/)
#
# Copyright (c) 2016-2022 Docker, Inc.
#
# It is licensed under the Apache 2.0 license (see LICENSES/Apache-2.0.txt in this collection)
# SPDX-License-Identifier: Apache-2.0

from __future__ import annotations


"""Filename matching with shell patterns.

fnmatch(FILENAME, PATTERN) matches according to the local convention.
fnmatchcase(FILENAME, PATTERN) always takes case in account.

The functions operate by translating the pattern into a regular
expression.  They cache the compiled regular expressions for speed.

The function translate(PATTERN) returns a regular expression
corresponding to PATTERN.  (It does not compile it.)
"""

import re


__all__ = ["fnmatch", "fnmatchcase", "translate"]

_cache = {}
_MAXCACHE = 100


def _purge():
    """Clear the pattern cache"""
    _cache.clear()


def fnmatch(name, pat):
    """Test whether FILENAME matches PATTERN.

    Patterns are Unix shell style:

    *       matches everything
    ?       matches any single character
    [seq]   matches any character in seq
    [!seq]  matches any char not in seq

    An initial period in FILENAME is not special.
    Both FILENAME and PATTERN are first case-normalized
    if the operating system requires it.
    If you do not want this, use fnmatchcase(FILENAME, PATTERN).
    """

    name = name.lower()
    pat = pat.lower()
    return fnmatchcase(name, pat)


def fnmatchcase(name, pat):
    """Test whether FILENAME matches PATTERN, including case.
    This is a version of fnmatch() which does not case-normalize
    its arguments.
    """

    try:
        re_pat = _cache[pat]
    except KeyError:
        res = translate(pat)
        if len(_cache) >= _MAXCACHE:
            _cache.clear()
        _cache[pat] = re_pat = re.compile(res)
    return re_pat.match(name) is not None


def translate(pat):
    """Translate a shell PATTERN to a regular expression.

    There is no way to quote meta-characters.
    """
    i, n = 0, len(pat)
    res = "^"
    while i < n:
        c = pat[i]
        i = i + 1
        if c == "*":
            if i < n and pat[i] == "*":
                # is some flavor of "**"
                i = i + 1
                # Treat **/ as ** so eat the "/"
                if i < n and pat[i] == "/":
                    i = i + 1
                if i >= n:
                    # is "**EOF" - to align with .gitignore just accept all
                    res = res + ".*"
                else:
                    # is "**"
                    # Note that this allows for any # of /'s (even 0) because
                    # the .* will eat everything, even /'s
                    res = res + "(.*/)?"
            else:
                # is "*" so map it to anything but "/"
                res = res + "[^/]*"
        elif c == "?":
            # "?" is any char except "/"
            res = res + "[^/]"
        elif c == "[":
            j = i
            if j < n and pat[j] == "!":
                j = j + 1
            if j < n and pat[j] == "]":
                j = j + 1
            while j < n and pat[j] != "]":
                j = j + 1
            if j >= n:
                res = res + "\\["
            else:
                stuff = pat[i:j].replace("\\", "\\\\")
                i = j + 1
                if stuff[0] == "!":
                    stuff = "^" + stuff[1:]
                elif stuff[0] == "^":
                    stuff = "\\" + stuff
                res = f"{res}[{stuff}]"
        else:
            res = res + re.escape(c)

    return res + "$"