"""
Internal constants.
"""

import os
import sys

from snakeoil import mappings

from . import __title__

osp = os.path
_reporoot = osp.realpath(__file__).rsplit(os.path.sep, 3)[0]
_module = sys.modules[__name__]

try:
    # This is a file written during pkgcore installation;
    # if it exists, we defer to it.  If it doesn't, then we're
    # running from a git checkout or a tarball.
    from . import _const as _defaults
except ImportError:
    _defaults = object()


def _GET_CONST(attr, default_value):
    consts = mappings.ProxiedAttrs(_module)
    is_tuple = not isinstance(default_value, str)
    if is_tuple:
        default_value = tuple(x % consts for x in default_value)
    else:
        default_value %= consts

    result = getattr(_defaults, attr, default_value)
    if is_tuple:
        result = tuple(result)
    return result


# determine XDG compatible paths
for xdg_var, var_name, fallback_dir in (
    ("XDG_CONFIG_HOME", "USER_CONFIG_PATH", "~/.config"),
    ("XDG_CACHE_HOME", "USER_CACHE_PATH", "~/.cache"),
    ("XDG_DATA_HOME", "USER_DATA_PATH", "~/.local/share"),
):
    setattr(
        _module,
        var_name,
        os.environ.get(xdg_var, osp.join(osp.expanduser(fallback_dir), __title__)),
    )

USER_CONF_FILE = osp.join(getattr(_module, "USER_CONFIG_PATH"), "pkgcore.conf")
SYSTEM_CONF_FILE = "/etc/pkgcore/pkgcore.conf"
SYSTEM_CACHE_PATH = "/var/cache/pkgcore"

REPO_PATH = _GET_CONST("REPO_PATH", _reporoot)
DATA_PATH = _GET_CONST("DATA_PATH", "%(REPO_PATH)s/data/share/pkgcore")
LIBDIR_PATH = _GET_CONST("LIBDIR_PATH", "%(REPO_PATH)s/data/lib/pkgcore")
EBD_PATH = _GET_CONST("EBD_PATH", "%(LIBDIR_PATH)s/ebd")
CONFIG_PATH = _GET_CONST("CONFIG_PATH", "%(DATA_PATH)s/config")
PATH_FORCED_PREPEND = _GET_CONST("INJECTED_BIN_PATH", ("%(REPO_PATH)s/bin",))
