import os
from contextlib import contextmanager
from zipfile import ZipFile


def parse_dict(parsers, data):
    """
    Make a generator that yields callables applying parser functions to their
    matching input data. *parsers* and *data* must both be dictionaries. Parser
    functions are matched to input data using their dictionary keys. If a
    parser's key is not present in *data*, it is ignored.

    A key in *parsers* may map to another dictionary of parsers. In this case,
    this function will be applied recursively to the matching value in *data*,
    which is assumed to be a dictionary as well.

    If a parser is matched to a list type, one callable for each list item is
    yielded.

    :param dict parsers: A mapping of parsers.
    :param dict data: A mapping of data to be parsed.
    """
    for field, parser in parsers.items():
        if field not in data:
            continue

        value = data[field]

        if isinstance(value, list):
            yield from [lambda i=x: parser(i) for x in value]
        elif isinstance(value, dict):
            yield from parse_dict(parser, value)
        else:
            yield lambda: parser(value)


@contextmanager
def open_archive_file(archive, member, check_sidecar=True):  # pragma: no cover
    """
    Open an archive file for use with the :ref:`with <with>` statement. Yields
    a :term:`file object` obtained from:

    1. The archive's :ref:`sidecar file <sidecar-files>`, if it exists and
       *check_sidecar* is ``True``.
    2. Otherwise, the archive itself.

    :param Archive archive: The archive.
    :param str member: The name of the file within the archive (or its sidecar suffix).
    :param bool check_sidecar: Whether to check for the sidecar file.
    """
    if check_sidecar:
        sidecar = f"{archive.path}.{member}"

        if os.path.exists(sidecar):
            with open(sidecar, "r") as file:
                yield file

            return

    with ZipFile(archive.path, "r") as zip:
        with zip.open(member, "r") as file:
            yield file