# resourceutil.py - utility for looking up resources

#

#  Copyright 2005 K. Thananchayan <thananck@yahoo.com>

#  Copyright 2005-2007 Olivia Mackall <olivia@selenic.com>

#  Copyright 2006 Vadim Gelfer <vadim.gelfer@gmail.com>

#

# This software may be used and distributed according to the terms of the

# GNU General Public License version 2 or any later version.

import _imp

import os

import sys

from .. import pycompat

def mainfrozen():

    """return True if we are a frozen executable.

    The code supports py2exe (most common, Windows only) and tools/freeze

    (portable, not much used).

    """

    return (

        hasattr(sys, "frozen")  # new py2exe

        or hasattr(sys, "importers")  # old py2exe

        or _imp.is_frozen("__main__")  # tools/freeze

    )

# the location of data files matching the source code

if mainfrozen() and getattr(sys, "frozen", None) != "macosx_app":

    # executable version (py2exe) doesn't support __file__

    datapath = os.path.dirname(pycompat.sysexecutable)

    _rootpath = datapath

    # The installers store the files outside of library.zip, like

    # C:\Program Files\Mercurial\defaultrc\*.rc.  This strips the

    # leading "mercurial." off of the package name, so that these

    # pseudo resources are found in their directory next to the

    # executable.

    def _package_path(package):

        dirs = package.split(b".")

        assert dirs[0] == b"mercurial"

        return os.path.join(_rootpath, *dirs[1:])

else:

    datapath = os.path.dirname(os.path.dirname(pycompat.fsencode(__file__)))

    _rootpath = os.path.dirname(datapath)

    def _package_path(package):

        return os.path.join(_rootpath, *package.split(b"."))

try:

    # importlib.resources exists from Python 3.7; see fallback in except clause

    # further down

    from importlib import resources  # pytype: disable=import-error

    # Force loading of the resources module

    if hasattr(resources, 'files'):

        resources.files  # pytype: disable=module-attr

    else:

        resources.open_binary  # pytype: disable=module-attr

    # py2exe raises an AssertionError if uses importlib.resources

    if getattr(sys, "frozen", None) in ("console_exe", "windows_exe"):

        raise ImportError

except (ImportError, AttributeError):

    # importlib.resources was not found (almost definitely because we're on a

    # Python version before 3.7)

    def open_resource(package, name):

        path = os.path.join(_package_path(package), name)

        return open(path, "rb")

    def is_resource(package, name):

        path = os.path.join(_package_path(package), name)

        try:

            return os.path.isfile(pycompat.fsdecode(path))

        except (IOError, OSError):

            return False

    def contents(package):

        path = pycompat.fsdecode(_package_path(package))

        for p in os.listdir(path):

            yield pycompat.fsencode(p)

else:

    from .. import encoding

    def open_resource(package, name):

        if hasattr(resources, 'files'):

            return (

                resources.files(  # pytype: disable=module-attr

                    pycompat.sysstr(package)

                )

                .joinpath(pycompat.sysstr(name))

                .open('rb')

            )

        else:

            return resources.open_binary(  # pytype: disable=module-attr

                pycompat.sysstr(package), pycompat.sysstr(name)

            )

    def is_resource(package, name):

        return resources.is_resource(  # pytype: disable=module-attr

            pycompat.sysstr(package), encoding.strfromlocal(name)

        )

    def contents(package):

        # pytype: disable=module-attr

        for r in resources.contents(pycompat.sysstr(package)):

            # pytype: enable=module-attr

            yield encoding.strtolocal(r)