from __future__ import absolute_import

import contextlib
import errno
import io
import locale
# we have a submodule named 'logging' which would shadow this if we used the
# regular name:
import logging as std_logging
import os
import posixpath
import re
import shutil
import stat
import subprocess
import sys
import tarfile
import zipfile
from collections import deque

from pip._vendor import pkg_resources
# NOTE: retrying is not annotated in typeshed as on 2017-07-17, which is
#       why we ignore the type on this import.
from pip._vendor.retrying import retry  # type: ignore
from pip._vendor.six import PY2
from pip._vendor.six.moves import input
from pip._vendor.six.moves.urllib import parse as urllib_parse

from pip._internal.exceptions import CommandError, InstallationError
from pip._internal.locations import (
    running_under_virtualenv, site_packages, user_site, virtualenv_no_global,
    write_delete_marker_file,
)
from pip._internal.utils.compat import (
    WINDOWS, console_to_str, expanduser, stdlib_pkgs,
)

if PY2:
    from io import BytesIO as StringIO
else:
    from io import StringIO

__all__ = ['rmtree', 'display_path', 'backup_dir',
           'ask', 'splitext',
           'format_size', 'is_installable_dir',
           'is_svn_page', 'file_contents',
           'split_leading_dir', 'has_leading_dir',
           'normalize_path',
           'renames', 'get_prog',
           'unzip_file', 'untar_file', 'unpack_file', 'call_subprocess',
           'captured_stdout', 'ensure_dir',
           'ARCHIVE_EXTENSIONS', 'SUPPORTED_EXTENSIONS',
           'get_installed_version', 'remove_auth_from_url']


logger = std_logging.getLogger(__name__)

BZ2_EXTENSIONS = ('.tar.bz2', '.tbz')
XZ_EXTENSIONS = ('.tar.xz', '.txz', '.tlz', '.tar.lz', '.tar.lzma')
ZIP_EXTENSIONS = ('.zip', '.whl')
TAR_EXTENSIONS = ('.tar.gz', '.tgz', '.tar')
ARCHIVE_EXTENSIONS = (
    ZIP_EXTENSIONS + BZ2_EXTENSIONS + TAR_EXTENSIONS + XZ_EXTENSIONS)
SUPPORTED_EXTENSIONS = ZIP_EXTENSIONS + TAR_EXTENSIONS
try:
    import bz2  # noqa
    SUPPORTED_EXTENSIONS += BZ2_EXTENSIONS
except ImportError:
    logger.debug('bz2 module is not available')

try:
    # Only for Python 3.3+
    import lzma  # noqa
    SUPPORTED_EXTENSIONS += XZ_EXTENSIONS
except ImportError:
    logger.debug('lzma module is not available')


def import_or_raise(pkg_or_module_string, ExceptionType, *args, **kwargs):
    try:
        return __import__(pkg_or_module_string)
    except ImportError:
        raise ExceptionType(*args, **kwargs)


def ensure_dir(path):
    """os.path.makedirs without EEXIST."""
    try:
        os.makedirs(path)
    except OSError as e:
        if e.errno != errno.EEXIST:
            raise


def get_prog():
    try:
        prog = os.path.basename(sys.argv[0])
        if prog in ('__main__.py', '-c'):
            return "%s -m pip" % sys.executable
        else:
            return prog
    except (AttributeError, TypeError, IndexError):
        pass
    return 'pip'


# Retry every half second for up to 3 seconds
@retry(stop_max_delay=3000, wait_fixed=500)
def rmtree(dir, ignore_errors=False):
    shutil.rmtree(dir, ignore_errors=ignore_errors,
                  onerror=rmtree_errorhandler)


def rmtree_errorhandler(func, path, exc_info):
    """On Windows, the files in .svn are read-only, so when rmtree() tries to
    remove them, an exception is thrown.  We catch that here, remove the
    read-only attribute, and hopefully continue without problems."""
    # if file type currently read only
    if os.stat(path).st_mode & stat.S_IREAD:
        # convert to read/write
        os.chmod(path, stat.S_IWRITE)
        # use the original function to repeat the operation
        func(path)
        return
    else:
        raise


def display_path(path):
    """Gives the display value for a given path, making it relative to cwd
    if possible."""
    path = os.path.normcase(os.path.abspath(path))
    if sys.version_info[0] == 2:
        path = path.decode(sys.getfilesystemencoding(), 'replace')
        path = path.encode(sys.getdefaultencoding(), 'replace')
    if path.startswith(os.getcwd() + os.path.sep):
        path = '.' + path[len(os.getcwd()):]
    return path


def backup_dir(dir, ext='.bak'):
    """Figure out the name of a directory to back up the given dir to
    (adding .bak, .bak2, etc)"""
    n = 1
    extension = ext
    while os.path.exists(dir + extension):
        n += 1
        extension = ext + str(n)
    return dir + extension


def ask_path_exists(message, options):
    for action in os.environ.get('PIP_EXISTS_ACTION', '').split():
        if action in options:
            return action
    return ask(message, options)


def ask(message, options):
    """Ask the message interactively, with the given possible responses"""
    while 1:
        if os.environ.get('PIP_NO_INPUT'):
            raise Exception(
                'No input was expected ($PIP_NO_INPUT set); question: %s' %
                message
            )
        response = input(message)
        response = response.strip().lower()
        if response not in options:
            print(
                'Your response (%r) was not one of the expected responses: '
                '%s' % (response, ', '.join(options))
            )
        else:
            return response


def format_size(bytes):
    if bytes > 1000 * 1000:
        return '%.1fMB' % (bytes / 1000.0 / 1000)
    elif bytes > 10 * 1000:
        return '%ikB' % (bytes / 1000)
    elif bytes > 1000:
        return '%.1fkB' % (bytes / 1000.0)
    else:
        return '%ibytes' % bytes


def is_installable_dir(path):
    """Is path is a directory containing setup.py or pyproject.toml?
    """
    if not os.path.isdir(path):
        return False
    setup_py = os.path.join(path, 'setup.py')
    if os.path.isfile(setup_py):
        return True
    pyproject_toml = os.path.join(path, 'pyproject.toml')
    if os.path.isfile(pyproject_toml):
        return True
    return False


def is_svn_page(html):
    """
    Returns true if the page appears to be the index page of an svn repository
    """
    return (re.search(r'<title>[^<]*Revision \d+:', html) and
            re.search(r'Powered by (?:<a[^>]*?>)?Subversion', html, re.I))


def file_contents(filename):
    with open(filename, 'rb') as fp:
        return fp.read().decode('utf-8')


def read_chunks(file, size=io.DEFAULT_BUFFER_SIZE):
    """Yield pieces of data from a file-like object until EOF."""
    while True:
        chunk = file.read(size)
        if not chunk:
            break
        yield chunk


def split_leading_dir(path):
    path = path.lstrip('/').lstrip('\\')
    if '/' in path and (('\\' in path and path.find('/') < path.find('\\')) or
                        '\\' not in path):
        return path.split('/', 1)
    elif '\\' in path:
        return path.split('\\', 1)
    else:
        return path, ''


def has_leading_dir(paths):
    """Returns true if all the paths have the same leading path name
    (i.e., everything is in one subdirectory in an archive)"""
    common_prefix = None
    for path in paths:
        prefix, rest = split_leading_dir(path)
        if not prefix:
            return False
        elif common_prefix is None:
            common_prefix = prefix
        elif prefix != common_prefix:
            return False
    return True


def normalize_path(path, resolve_symlinks=True):
    """
    Convert a path to its canonical, case-normalized, absolute version.

    """
    path = expanduser(path)
    if resolve_symlinks:
        path = os.path.realpath(path)
    else:
        path = os.path.abspath(path)
    return os.path.normcase(path)


def splitext(path):
    """Like os.path.splitext, but take off .tar too"""
    base, ext = posixpath.splitext(path)
    if base.lower().endswith('.tar'):
        ext = base[-4:] + ext
        base = base[:-4]
    return base, ext


def renames(old, new):
    """Like os.renames(), but handles renaming across devices."""
    # Implementation borrowed from os.renames().
    head, tail = os.path.split(new)
    if head and tail and not os.path.exists(head):
        os.makedirs(head)

    shutil.move(old, new)

    head, tail = os.path.split(old)
    if head and tail:
        try:
            os.removedirs(head)
        except OSError:
            pass


def is_local(path):
    """
    Return True if path is within sys.prefix, if we're running in a virtualenv.

    If we're not in a virtualenv, all paths are considered "local."

    """
    if not running_under_virtualenv():
        return True
    return normalize_path(path).startswith(normalize_path(sys.prefix))


def dist_is_local(dist):
    """
    Return True if given Distribution object is installed locally
    (i.e. within current virtualenv).

    Always True if we're not in a virtualenv.

    """
    return is_local(dist_location(dist))


def dist_in_usersite(dist):
    """
    Return True if given Distribution is installed in user site.
    """
    norm_path = normalize_path(dist_location(dist))
    return norm_path.startswith(normalize_path(user_site))


def dist_in_site_packages(dist):
    """
    Return True if given Distribution is installed in
    sysconfig.get_python_lib().
    """
    return normalize_path(
        dist_location(dist)
    ).startswith(normalize_path(site_packages))


def dist_is_editable(dist):
    """Is distribution an editable install?"""
    for path_item in sys.path:
        egg_link = os.path.join(path_item, dist.project_name + '.egg-link')
        if os.path.isfile(egg_link):
            return True
    return False


def get_installed_distributions(local_only=True,
                                skip=stdlib_pkgs,
                                include_editables=True,
                                editables_only=False,
                                user_only=False):
    """