from distutils import log
import distutils.command.sdist as orig
import os
import sys
import io
import contextlib
from glob import iglob

from setuptools.extern import ordered_set

from .py36compat import sdist_add_defaults

import pkg_resources

_default_revctrl = list


def walk_revctrl(dirname=""):
    """Find all files under revision control"""
    for ep in pkg_resources.iter_entry_points("setuptools.file_finders"):
        for item in ep.load()(dirname):
            yield item


class sdist(sdist_add_defaults, orig.sdist):
    """Smart sdist that finds anything supported by revision control"""

    user_options = [
        ("formats=", None, "formats for source distribution (comma-separated list)"),
        (
            "keep-temp",
            "k",
            "keep the distribution tree around after creating " + "archive file(s)",
        ),
        (
            "dist-dir=",
            "d",
            "directory to put the source distribution archive(s) in " "[default: dist]",
        ),
    ]

    negative_opt = {}

    README_EXTENSIONS = ["", ".rst", ".txt", ".md"]
    READMES = tuple("README{0}".format(ext) for ext in README_EXTENSIONS)

    def run(self):
        self.run_command("egg_info")
        ei_cmd = self.get_finalized_command("egg_info")
        self.filelist = ei_cmd.filelist
        self.filelist.append(os.path.join(ei_cmd.egg_info, "SOURCES.txt"))
        self.check_readme()

        # Run sub commands
        for cmd_name in self.get_sub_commands():
            self.run_command(cmd_name)

        self.make_distribution()

        dist_files = getattr(self.distribution, "dist_files", [])
        for file in self.archive_files:
            data = ("sdist", "", file)
            if data not in dist_files:
                dist_files.append(data)

    def initialize_options(self):
        orig.sdist.initialize_options(self)

        self._default_to_gztar()

    def _default_to_gztar(self):
        # only needed on Python prior to 3.6.
        if sys.version_info >= (3, 6, 0, "beta", 1):
            return
        self.formats = ["gztar"]

    def make_distribution(self):
        """
        Workaround for #516
        """
        with self._remove_os_link():
            orig.sdist.make_distribution(self)

    @staticmethod
    @contextlib.contextmanager
    def _remove_os_link():
        """
        In a context, remove and restore os.link if it exists
        """

        class NoValue:
            pass

        orig_val = getattr(os, "link", NoValue)
        try:
            del os.link
        except Exception:
            pass
        try:
            yield
        finally:
            if orig_val is not NoValue:
                setattr(os, "link", orig_val)

    def _add_defaults_optional(self):
        super()._add_defaults_optional()
        if os.path.isfile("pyproject.toml"):
            self.filelist.append("pyproject.toml")

    def _add_defaults_python(self):
        """getting python files"""
        if self.distribution.has_pure_modules():
            build_py = self.get_finalized_command("build_py")
            self.filelist.extend(build_py.get_source_files())
            self._add_data_files(self._safe_data_files(build_py))

    def _safe_data_files(self, build_py):
        """
        Extracting data_files from build_py is known to cause
        infinite recursion errors when `include_package_data`
        is enabled, so suppress it in that case.
        """
        if self.distribution.include_package_data:
            return ()
        return build_py.data_files

    def _add_data_files(self, data_files):
        """
        Add data files as found in build_py.data_files.
        """
        self.filelist.extend(
            os.path.join(src_dir, name)
            for _, src_dir, _, filenames in data_files
            for name in filenames
        )

    def _add_defaults_data_files(self):
        try:
            super()._add_defaults_data_files()
        except TypeError:
            log.warn("data_files contains unexpected objects")

    def check_readme(self):
        for f in self.READMES:
            if os.path.exists(f):
                return
        else:
            self.warn(
                "standard file not found: should have one of " + ", ".join(self.READMES)
            )

    def make_release_tree(self, base_dir, files):
        orig.sdist.make_release_tree(self, base_dir, files)

        # Save any egg_info command line options used to create this sdist
        dest = os.path.join(base_dir, "setup.cfg")
        if hasattr(os, "link") and os.path.exists(dest):
            # unlink and re-copy, since it might be hard-linked, and
            # we don't want to change the source version
            os.unlink(dest)
            self.copy_file("setup.cfg", dest)

        self.get_finalized_command("egg_info").save_version_info(dest)

    def _manifest_is_not_generated(self):
        # check for special comment used in 2.7.1 and higher
        if not os.path.isfile(self.manifest):
            return False

        with io.open(self.manifest, "rb") as fp:
            first_line = fp.readline()
        return first_line != "# file GENERATED by distutils, do NOT edit\n".encode()

    def read_manifest(self):
        """Read the manifest file (named by 'self.manifest') and use it to
        fill in 'self.filelist', the list of files to include in the source
        distribution.
        """
        log.info("reading manifest file '%s'", self.manifest)
        manifest = open(self.manifest, "rb")
        for line in manifest:
            # The manifest must contain UTF-8. See #303.
            try:
                line = line.decode("UTF-8")
            except UnicodeDecodeError:
                log.warn("%r not UTF-8 decodable -- skipping" % line)
                continue
            # ignore comments and blank lines
            line = line.strip()
            if line.startswith("#") or not line:
                continue
            self.filelist.append(line)
        manifest.close()

    def check_license(self):
        """Checks if license_file' or 'license_files' is configured and adds any
        valid paths to 'self.filelist'.
        """
        opts = self.distribution.get_option_dict("metadata")

        files = ordered_set.OrderedSet()
        try:
            license_files = self.distribution.metadata.license_files
        except TypeError:
            log.warn("warning: 'license_files' option is malformed")
            license_files = ordered_set.OrderedSet()
        patterns = (
            license_files
            if isinstance(license_files, ordered_set.OrderedSet)
            else ordered_set.OrderedSet(license_files)
        )

        if "license_file" in opts:
            log.warn(
                "warning: the 'license_file' option is deprecated, "
                "use 'license_files' instead"
            )
            patterns.append(opts["license_file"][1])

        if "license_file" not in opts and "license_files" not in opts:
            # Default patterns match the ones wheel uses
            # See https://wheel.readthedocs.io/en/stable/user_guide.html
            # -> 'Including license files in the generated wheel file'
            patterns = ("LICEN[CS]E*", "COPYING*", "NOTICE*", "AUTHORS*")

        for pattern in patterns:
            for path in iglob(pattern):
                if path.endswith("~"):
                    log.debug(
                        "ignoring license file '%s' as it looks like a backup", path
                    )
                    continue

                if path not in files and os.path.isfile(path):
                    log.info(
                        "adding license file '%s' (matched pattern '%s')", path, pattern
                    )
                    files.add(path)

        self.filelist.extend(sorted(files))
