#! /usr/bin/python3.8
#
# Argument Clinic
# Copyright 2012-2013 by Larry Hastings.
# Licensed to the PSF under a contributor agreement.
#

import abc
import ast
import collections
import contextlib
import copy
import cpp
import functools
import hashlib
import inspect
import io
import itertools
import os
import pprint
import re
import shlex
import string
import sys
import tempfile
import textwrap
import traceback
import types

from types import *
NoneType = type(None)

# TODO:
#
# soon:
#
# * allow mixing any two of {positional-only, positional-or-keyword,
#   keyword-only}
#       * dict constructor uses positional-only and keyword-only
#       * max and min use positional only with an optional group
#         and keyword-only
#

version = '1'

NoneType = type(None)

class Unspecified:
    def __repr__(self):
        return '<Unspecified>'

unspecified = Unspecified()


class Null:
    def __repr__(self):
        return '<Null>'

NULL = Null()


class Unknown:
    def __repr__(self):
        return '<Unknown>'

unknown = Unknown()

sig_end_marker = '--'


_text_accumulator_nt = collections.namedtuple("_text_accumulator", "text append output")

def _text_accumulator():
    text = []
    def output():
        s = ''.join(text)
        text.clear()
        return s
    return _text_accumulator_nt(text, text.append, output)


text_accumulator_nt = collections.namedtuple("text_accumulator", "text append")

def text_accumulator():
    """
    Creates a simple text accumulator / joiner.

    Returns a pair of callables:
        append, output
    "append" appends a string to the accumulator.
    "output" returns the contents of the accumulator
       joined together (''.join(accumulator)) and
       empties the accumulator.
    """
    text, append, output = _text_accumulator()
    return text_accumulator_nt(append, output)


def warn_or_fail(fail=False, *args, filename=None, line_number=None):
    joined = " ".join([str(a) for a in args])
    add, output = text_accumulator()
    if fail:
        add("Error")
    else:
        add("Warning")
    if clinic:
        if filename is None:
            filename = clinic.filename
        if getattr(clinic, 'block_parser', None) and (line_number is None):
            line_number = clinic.block_parser.line_number
    if filename is not None:
        add(' in file "' + filename + '"')
    if line_number is not None:
        add(" on line " + str(line_number))
    add(':\n')
    add(joined)
    print(output())
    if fail:
        sys.exit(-1)


def warn(*args, filename=None, line_number=None):
    return warn_or_fail(False, *args, filename=filename, line_number=line_number)

def fail(*args, filename=None, line_number=None):
    return warn_or_fail(True, *args, filename=filename, line_number=line_number)


def quoted_for_c_string(s):
    for old, new in (
        ('\\', '\\\\'), # must be first!
        ('"', '\\"'),
        ("'", "\\'"),
        ):
        s = s.replace(old, new)
    return s

def c_repr(s):
    return '"' + s + '"'


is_legal_c_identifier = re.compile('^[A-Za-z_][A-Za-z0-9_]*$').match

def is_legal_py_identifier(s):
    return all(is_legal_c_identifier(field) for field in s.split('.'))

# identifiers that are okay in Python but aren't a good idea in C.
# so if they're used Argument Clinic will add "_value" to the end
# of the name in C.
c_keywords = set("""
asm auto break case char const continue default do double
else enum extern float for goto if inline int long
register return short signed sizeof static struct switch
typedef typeof union unsigned void volatile while
""".strip().split())

def ensure_legal_c_identifier(s):
    # for now, just complain if what we're given isn't legal
    if not is_legal_c_identifier(s):
        fail("Illegal C identifier: {}".format(s))
    # but if we picked a C keyword, pick something else
    if s in c_keywords:
        return s + "_value"
    return s

def rstrip_lines(s):
    text, add, output = _text_accumulator()
    for line in s.split('\n'):
        add(line.rstrip())
        add('\n')
    text.pop()
    return output()

def format_escape(s):
    # double up curly-braces, this string will be used
    # as part of a format_map() template later
    s = s.replace('{', '{{')
    s = s.replace('}', '}}')
    return s

def linear_format(s, **kwargs):
    """
    Perform str.format-like substitution, except:
      * The strings substituted must be on lines by
        themselves.  (This line is the "source line".)
      * If the substitution text is empty, the source line
        is removed in the output.
      * If the field is not recognized, the original line
        is passed unmodified through to the output.
      * If the substitution text is not empty:
          * Each line of the substituted text is indented
            by the indent of the source line.
          * A newline will be added to the end.
    """

    add, output = text_accumulator()
    for line in s.split('\n'):
        indent, curly, trailing = line.partition('{')
        if not curly:
            add(line)
            add('\n')
            continue

        name, curly, trailing = trailing.partition('}')
        if not curly or name not in kwargs:
            add(line)
            add('\n')
            continue

        if trailing:
            fail("Text found after {" + name + "} block marker!  It must be on a line by itself.")
        if indent.strip():
            fail("Non-whitespace characters found before {" + name + "} block marker!  It must be on a line by itself.")

        value = kwargs[name]
        if not value:
            continue

        value = textwrap.indent(rstrip_lines(value), indent)
        add(value)
        add('\n')

    return output()[:-1]

def indent_all_lines(s, prefix):
    """
    Returns 's', with 'prefix' prepended to all lines.

    If the last line is empty, prefix is not prepended
    to it.  (If s is blank, returns s unchanged.)

    (textwrap.indent only adds to non-blank lines.)
    """
    split = s.split('\n')
    last = split.pop()
    final = []
    for line in split:
        final.append(prefix)
        final.append(line)
        final.append('\n')
    if last:
        final.append(prefix)
        final.append(last)
    return ''.join(final)

def suffix_all_lines(s, suffix):
    """
    Returns 's', with 'suffix' appended to all lines.

    If the last line is empty, suffix is not appended
    to it.  (If s is blank, returns s unchanged.)
    """
    split = s.split('\n')
    last = split.pop()
    final = []
    for line in split:
        final.append(line)
        final.append(suffix)
        final.append('\n')
    if last:
        final.append(last)
        final.append(suffix)
    return ''.join(final)


def version_splitter(s):
    """Splits a version string into a tuple of integers.

    The following ASCII characters are allowed, and employ
    the following conversions:
        a -> -3
        b -> -2
        c -> -1
    (This permits Python-style version strings such as "1.4b3".)
    """
    version = []
    accumulator = []
    def flush():
        if not accumulator:
            raise ValueError('Unsupported version string: ' + repr(s))
        version.append(int(''.join(accumulator)))
        accumulator.clear()

    for c in s:
        if c.isdigit():
            accumulator.append(c)
        elif c == '.':
            flush()
        elif c in 'abc':
            flush()
            version.append('abc'.index(c) - 3)
        else:
            raise ValueError('Illegal character ' + repr(c) + ' in version string ' + repr(s))
    flush()
    return tuple(version)

def version_comparitor(version1, version2):
    iterator = itertools.zip_longest(version_splitter(version1), version_splitter(version2), fillvalue=0)
    for i, (a, b) in enumerate(iterator):
        if a < b:
            return -1
        if a > b:
            return 1
    return 0


class CRenderData:
    def __init__(self):

        # The C statements to declare variables.
        # Should be full lines with \n eol characters.
        self.declarations = []

        # The C statements required to initialize the variables before the parse call.
        # Should be full lines with \n eol characters.
        self.initializers = []

        # The C statements needed to dynamically modify the values
        # parsed by the parse call, before calling the impl.
        self.modifications = []

        # The entries for the "keywords" array for PyArg_ParseTuple.
        # Should be individual strings representing the names.
        self.keywords = []

        # The "format units" for PyArg_ParseTuple.
        # Should be individual strings that will get
        self.format_units = []

        # The varargs arguments for PyArg_ParseTuple.
        self.parse_arguments = []

        # The parameter declarations for the impl function.
        self.impl_parameters = []

        # The arguments to the impl function at the time it's called.
        self.impl_arguments = []

        # For return converters: the name of the variable that
        # should receive the value returned by the impl.
        self.return_value = "return_value"

        # For return converters: the code to convert the return
        # value from the parse function.  This is also where
        # you should check the _return_value for errors, and