# SPDX-License-Identifier: AGPL-3.0-or-later

# Building Hydrilla packages.
#
# This file is part of Hydrilla
#
# Copyright (C) 2021, 2022 Wojtek Kosior
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <https://www.gnu.org/licenses/>.
#
#
# I, Wojtek Kosior, thereby promise not to sue for violation of this
# file's license. Although I request that you do not make use this code
# in a proprietary program, I am not going to enforce this in court.

import re as _re
import json as _json

from typing import Optional as _Optional

_strip_comment_re = _re.compile(r'''
^ # match from the beginning of each line
( # catch the part before '//' comment
  (?: # this group matches either a string or a single out-of-string character
    [^"/] |
    "
    (?: # this group matches any in-a-string character
      [^"\\] |          # match any normal character
      \\[^u] |          # match any escaped character like '\f' or '\n'
      \\u[a-fA-F0-9]{4} # match an escape
    )*
    "
  )*
)
# expect either end-of-line or a comment:
# * unterminated strings will cause matching to fail
# * bad comment (with '/' instead of '//') will be indicated by second group
#   having length 1 instead of 2 or 0
(//?|$)
''', _re.VERBOSE)

def strip_json_comments(text: str) -> str:
    """
    Accept JSON text with optional C++-style ('//') comments and return the text
    with comments removed. Consecutive slashes inside strings are handled
    properly. A spurious single slash ('/') shall generate an error. Errors in
    JSON itself shall be ignored.
    """
    processed = 0
    stripped_text = []
    for line in text.split('\n'):
        match = _strip_comment_re.match(line)

        if match is None: # unterminated string
            # ignore this error, let json module report it
            stripped = line
        elif len(match[2]) == 1:
            raise _json.JSONDecodeError('bad comment', text,
                                        processed + len(match[1]))
        else:
            stripped = match[1]

        stripped_text.append(stripped)
        processed += len(line) + 1

    return '\n'.join(stripped_text)

def normalize_version(ver: list[int]) -> list[int]:
    """Strip right-most zeroes from 'ver'. The original list is not modified."""
    new_len = 0
    for i, num in enumerate(ver):
        if num != 0:
            new_len = i + 1

    return ver[:new_len]

def parse_version(ver_str: str) -> list[int]:
    """
    Convert 'ver_str' into an array representation, e.g. for ver_str="4.6.13.0"
    return [4, 6, 13, 0].
    """
    return [int(num) for num in ver_str.split('.')]

def version_string(ver: list[int], rev: _Optional[int]=None) -> str:
    """
    Produce version's string representation (optionally with revision), like:
        1.2.3-5
    No version normalization is performed.
    """
    return '.'.join([str(n) for n in ver]) + ('' if rev is None else f'-{rev}')