from __future__ import annotations

from typing import TYPE_CHECKING

from .Cmd import Cmd, Parent
from .lib.templates import tmpl_render

if TYPE_CHECKING:
    from argparse import ArgumentParser, Namespace

class CmdCreatePkgConfig(Cmd):  # export

    def __init__(self, parent: Parent) -> None:
        super().__init__(
            parent,
            'create-pkg-config',
            help = 'Generate a pkg-config file for a module'
        )

    @staticmethod
    def __cleanup_requires(string: str) -> str:
        import re

        regexes = [
            (r'^ +', ''),
            (r'([ \t]|$)+', ', '),
            (r', $', ''),
            (r', $', ''),
            (r' *,* *([<>=]+) *,* *', r' \1 '),
        ]
        for patt, replacement in regexes:
            string = re.sub(patt, replacement, string)
        return string

    def add_arguments(self, parser: ArgumentParser) -> None:
        super().add_arguments(parser)
        parser.add_argument('-F', '--project-descr-file', default = None)
        parser.add_argument('-d', '--description', default = None)
        parser.add_argument('-n', '--name', default = None)
        parser.add_argument('-s', '--summary', default = None)
        parser.add_argument('-p', '--prefix', default = None)
        parser.add_argument('-v', '--version', default = None)
        parser.add_argument('-c', '--cflags', default = None)
        parser.add_argument('-l', '--libflags', default = None)
        parser.add_argument('-r', '--requires-run', default = None)
        parser.add_argument('-R', '--requires-build', default = None)
        parser.add_argument('-V', '--variables', nargs = '*')

    async def _run(self, args: Namespace) -> None:
        project_conf_var_keys = [
            'description',
            'summary',
            'requires_run',
            'requires_build',
        ]
        merged: dict[str, str | None] = {}
        for key in project_conf_var_keys:
            val = getattr(args, key)
            if val is not None and args.project_descr_file:
                val = self.app.get_value(args.name, key, None)
            merged[key] = val

        contents = tmpl_render(
            'pkg-config',
            [
                {
                    'prefix': args.prefix,
                    'name': args.name,
                    'description': merged['summary'] or '',
                    'version': args.version,
                }
            ]
        )

        if args.cflags is not None:
            contents += f'Cflags: {args.cflags}\n'
        if args.libflags is not None:
            contents += f'Libs: {args.libflags}\n'
        val = merged.get('requires_run')
        if val is not None:
            contents += f'Requires: {self.__cleanup_requires(val)}'
        val = merged.get('requires_build')
        if val is not None:
            contents += (f'Requires.private: {self.__cleanup_requires(val)}')
        # not sure what to do with requires_devel

        print(contents)