import os
from glob import glob
from distutils.util import convert_path
from distutils.command import sdist

from setuptools.extern.six.moves import filter


class sdist_add_defaults:
    """
    Mix-in providing forward-compatibility for functionality as found in
    distutils on Python 3.7.
    """

    def add_defaults(self):
        """Add all the default files to self.filelist:
          - README or README.txt
          - setup.py
          - test/test*.py
          - all pure Python modules mentioned in setup script
          - all files pointed by package_data (build_py)
          - all files defined in data_files.
          - all files defined as scripts.
          - all C sources listed as part of extensions or C libraries
            in the setup script (doesn't catch C headers!)
        Warns if (README or README.txt) or setup.py are missing; everything
        else is optional.
        """
        self._add_defaults_standards()
        self._add_defaults_optional()
        self._add_defaults_python()
        self._add_defaults_data_files()
        self._add_defaults_ext()
        self._add_defaults_c_libs()
        self._add_defaults_scripts()

    @staticmethod
    def _cs_path_exists(fspath):
        """
        Case-sensitive path existence check

        >>> sdist._cs_path_exists(__file__)
        True
        >>> sdist._cs_path_exists(__file__.upper())
        False
        """
        if not os.path.exists(fspath):
            return False
        # make absolute so we always have a directory
        abspath = os.path.abspath(fspath)
        directory, filename = os.path.split(abspath)
        return filename in os.listdir(directory)

    def _add_defaults_standards(self):
        standards = [self.READMES, self.distribution.script_name]
        for fn in standards:
            if isinstance(fn, tuple):
                alts = fn
                got_it = False
                for fn in alts:
                    if self._cs_path_exists(fn):
                        got_it = True
                        self.filelist.append(fn)
                        break

                if not got_it:
                    self.warn("standard file not found: should have one of " +
                              ', '.join(alts))
            else:
                if self._cs_path_exists(fn):
                    self.filelist.append(fn)
                else:
                    self.warn("standard file '%s' not found" % fn)

    def _add_defaults_optional(self):
        optional = ['test/test*.py', 'setup.cfg']
        for pattern in optional:
            files = filter(os.path.isfile, glob(pattern))
            self.filelist.extend(files)

    def _add_defaults_python(self):
        # build_py is used to get:
        #  - python modules
        #  - files defined in package_data
        build_py = self.get_finalized_command('build_py')

        # getting python files
        if self.distribution.has_pure_modules():
            self.filelist.extend(build_py.get_source_files())

        # getting package_data files
        # (computed in build_py.data_files by build_py.finalize_options)
        for pkg, src_dir, build_dir, filenames in build_py.data_files:
            for filename in filenames:
                self.filelist.append(os.path.join(src_dir, filename))

    def _add_defaults_data_files(self):
        # getting distribution.data_files
        if self.distribution.has_data_files():
            for item in self.distribution.data_files:
                if isinstance(item, str):
                    # plain file
                    item = convert_path(item)
                    if os.path.isfile(item):
                        self.filelist.append(item)
                else:
                    # a (dirname, filenames) tuple
                    dirname, filenames = item
                    for f in filenames:
                        f = convert_path(f)
                        if os.path.isfile(f):
                            self.filelist.append(f)

    def _add_defaults_ext(self):
        if self.distribution.has_ext_modules():
            build_ext = self.get_finalized_command('build_ext')
            self.filelist.extend(build_ext.get_source_files())

    def _add_defaults_c_libs(self):
        if self.distribution.has_c_libraries():
            build_clib = self.get_finalized_command('build_clib')
            self.filelist.extend(build_clib.get_source_files())

    def _add_defaults_scripts(self):
        if self.distribution.has_scripts():
            build_scripts = self.get_finalized_command('build_scripts')
            self.filelist.extend(build_scripts.get_source_files())


if hasattr(sdist.sdist, '_add_defaults_standards'):
    # disable the functionality already available upstream
    class sdist_add_defaults:
        pass