"""
This module deals with things that change between different versions
of the ASDF spec.
"""

from functools import total_ordering

import yaml
from semantic_version import SimpleSpec, Version

_yaml_base_loader = yaml.CSafeLoader if getattr(yaml, "__with_libyaml__", None) else yaml.SafeLoader


__all__ = ["AsdfVersion", "AsdfVersionMixin", "split_tag_version", "join_tag_version"]


def split_tag_version(tag):
    """
    Split a tag into its base and version.
    """
    name, version = tag.rsplit("-", 1)
    version = AsdfVersion(version)
    return name, version


def join_tag_version(name, version):
    """
    Join the root and version of a tag back together.
    """
    return f"{name}-{version}"


@total_ordering
class AsdfVersionMixin:
    """This mix-in is required in order to impose the total ordering that we
    want for ``AsdfVersion``, rather than accepting the total ordering that is
    already provided by ``Version`` from ``semantic_version``. Defining these
    comparisons directly in ``AsdfVersion`` and applying ``total_ordering``
    there will not work since ``total_ordering`` only defines comparison
    operations if they do not exist already and the base class ``Version``
    already defines these operations.
    """

    def __eq__(self, other):
        # Seems like a bit of a hack...
        if isinstance(other, SimpleSpec):
            return other == self
        if isinstance(other, (str, tuple, list)):
            other = AsdfVersion(other)
        return Version.__eq__(self, other)

    def __ne__(self, other):
        return not self.__eq__(other)

    def __lt__(self, other):
        if isinstance(other, (str, tuple, list)):
            other = AsdfVersion(other)
        return Version.__lt__(self, other)

    def __hash__(self):
        # To be honest, I'm not sure why I had to make this explicit
        return Version.__hash__(self)


class AsdfVersion(AsdfVersionMixin, Version):
    """This class adds features to the existing ``Version`` class from the
    ``semantic_version`` module. Namely, it allows ``Version`` objects to be
    constructed from tuples and lists as well as strings, and it allows
    ``Version`` objects to be compared with tuples, lists, and strings, instead
    of just other ``Version`` objects.

    If any of these features are added to the ``Version`` class itself (as
    requested in https://github.com/rbarrois/python-semanticversion/issues/52),
    then this class will become obsolete.
    """

    def __init__(self, version):
        # This is a dirty hack and you know it
        if isinstance(version, AsdfVersion):
            version = str(version)
        if isinstance(version, (tuple, list)):
            version = ".".join([str(x) for x in version])
        super().__init__(version)


supported_versions = [
    AsdfVersion("1.0.0"),
    AsdfVersion("1.1.0"),
    AsdfVersion("1.2.0"),
    AsdfVersion("1.3.0"),
    AsdfVersion("1.4.0"),
    AsdfVersion("1.5.0"),
    AsdfVersion("1.6.0"),
]


default_version = AsdfVersion("1.6.0")

# This is the ASDF Standard version that is currently in development
# it is possible that breaking changes will be made to this version.
asdf_standard_development_version = AsdfVersion("1.7.0")


# This is the ASDF Standard version at which the format of the history
# field changed to include extension metadata.
NEW_HISTORY_FORMAT_MIN_VERSION = AsdfVersion("1.2.0")


# This is the ASDF Standard version at which we begin restricting
# mapping keys to string, integer, and boolean only.
RESTRICTED_KEYS_MIN_VERSION = AsdfVersion("1.6.0")


# This library never removed defaults for ASDF Standard versions
# later than 1.5.0, so filling them isn't necessary.
FILL_DEFAULTS_MAX_VERSION = AsdfVersion("1.5.0")

# ASDF currently only defined a single file format version
_FILE_FORMAT_VERSION = AsdfVersion("1.0.0")

# ASDF currently only supports a single yaml version
# use a tuple as that is what yaml expects
_YAML_VERSION = (1, 1)
