#!/usr/bin/env python

# Copyright (C) 2016-2018 g10 Code GmbH
# Copyright (C) 2004,2008 Igor Belyi <belyi@users.sourceforge.net>
# Copyright (C) 2002 John Goerzen <jgoerzen@complete.org>
#
#    This library is free software; you can redistribute it and/or
#    modify it under the terms of the GNU Lesser General Public
#    License as published by the Free Software Foundation; either
#    version 2.1 of the License, or (at your option) any later version.
#
#    This library is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
#    Lesser General Public License for more details.
#
#    You should have received a copy of the GNU Lesser General Public
#    License along with this library; if not, write to the Free Software
#    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA

from distutils.core import setup, Extension
from distutils.command.build import build

import glob
import os
import os.path
import re
import shutil
import subprocess
import sys

# Out-of-tree build of the gpg bindings.
gpg_error_config = ["gpg-error-config"]
gpgme_config_flags = ["--thread=pthread"]
gpgme_config = ["gpgme-config"] + gpgme_config_flags
gpgme_h = ""
include_dirs = [os.getcwd()]
library_dirs = []
in_tree = False
extra_swig_opts = []
extra_macros = dict()

top_builddir = os.environ.get("top_builddir")
if top_builddir:
    # In-tree build.
    in_tree = True
    gpgme_config = [os.path.join(top_builddir, "src/gpgme-config")
                    ] + gpgme_config_flags
    gpgme_h = os.path.join(top_builddir, "src/gpgme.h")
    library_dirs = [os.path.join(top_builddir,
                                 "src/.libs")]  # XXX uses libtool internals
    extra_macros.update(
        HAVE_CONFIG_H=1,
        HAVE_DATA_H=1,
        IN_TREE_BUILD=1,
    )

if hasattr(subprocess, "DEVNULL"):
    devnull = subprocess.DEVNULL
else:
    devnull = open(os.devnull, "w")

try:
    subprocess.check_call(gpgme_config + ['--version'], stdout=devnull)
except:
    sys.exit("Could not find gpgme-config.  " +
             "Please install the libgpgme development package.")


def getconfig(what, config=gpgme_config):
    confdata = subprocess.Popen(
        config + ["--%s" % what], stdout=subprocess.PIPE).communicate()[0]
    return [x for x in confdata.decode('utf-8').split() if x != '']


version = version_raw = getconfig("version")[0]
if '-' in version:
    version = version.split('-')[0]
major, minor, patch = map(int, version.split('.'))

if not (major > 1 or (major == 1 and minor >= 7)):
    sys.exit('Need at least GPGME version 1.7, found {}.'.format(version_raw))

if not gpgme_h:
    gpgme_h = os.path.join(getconfig("prefix")[0], "include", "gpgme.h")

define_macros = []
libs = getconfig('libs')

# Define extra_macros for both the SWIG and C code
for k, v in extra_macros.items():
    extra_swig_opts.append("-D{0}={1}".format(k, v))
    define_macros.append((k, str(v)))

for item in getconfig('cflags'):
    if item.startswith("-I"):
        include_dirs.append(item[2:])
    elif item.startswith("-D"):
        defitem = item[2:].split("=", 1)
        if len(defitem) == 2:
            define_macros.append((defitem[0], defitem[1]))
        else:
            define_macros.append((defitem[0], None))

# Adjust include and library locations in case of win32
uname_s = os.popen("uname -s").read()
if uname_s.startswith("MINGW32"):
    mnts = [
        x.split()[0:3:2] for x in os.popen("mount").read().split("\n") if x
    ]
    tmplist = sorted([(len(x[1]), x[1], x[0]) for x in mnts])
    tmplist.reverse()
    extra_dirs = []
    for item in include_dirs:
        for ln, mnt, tgt in tmplist:
            if item.startswith(mnt):
                item = os.path.normpath(item[ln:])
                while item[0] == os.path.sep:
                    item = item[1:]
                extra_dirs.append(os.path.join(tgt, item))
                break
    include_dirs += extra_dirs
    for item in [x[2:] for x in libs if x.startswith("-L")]:
        for ln, mnt, tgt in tmplist:
            if item.startswith(mnt):
                item = os.path.normpath(item[ln:])
                while item[0] == os.path.sep:
                    item = item[1:]
                library_dirs.append(os.path.join(tgt, item))
                break


def in_srcdir(name):
    return os.path.join(os.environ.get("srcdir", ""), name)


def up_to_date(source, target):
    return (os.path.exists(target) and
            os.path.getmtime(source) <= os.path.getmtime(target))


# We build an Extension using SWIG, which generates a Python module.
# By default, the 'build_py' step is run before 'build_ext', and
# therefore the generated Python module is not copied into the build
# directory.
# Bugs: https://bugs.python.org/issue1016626
#       https://bugs.python.org/issue2624
# Workaround:
# https://stackoverflow.com/questions/12491328/python-distutils-not-include-the-swig-generated-module
#
# To install to multiple Python installations or to alternate ones run the
# following three commands (yes, run the build one twice):
#
# /path/to/pythonX.Y setup.py build
# /path/to/pythonX.Y setup.py build
# /path/to/pythonX.Y setup.py install
#
# It is highly likely that this will need to be run as root or with sudo (or
# sudo -H).  It may or may not work with venv. and outside a virtualenv

class BuildExtFirstHack(build):
    def _read_header(self, header, cflags):
        tmp_include = self._in_build_base("include1.h")
        with open(tmp_include, 'w') as f:
            f.write("#include <%s>" % header)
        return subprocess.check_output(
            os.environ.get('CPP', 'cc -E').split() + cflags +
            [tmp_include]).decode('utf-8')

    def _write_if_unchanged(self, target, content):
        if os.path.exists(target):
            with open(target) as f:
                if f.read() == content:
                    return

        with open(target, "w") as sink:
            sink.write(content)

    def _generate_gpgme_h(self, source_name, sink_name):
        print("Using gpgme.h from {}".format(source_name))
        shutil.copy2(source_name, sink_name)

    def _generate_errors_i(self):

        try:
            subprocess.check_call(
                gpg_error_config + ['--version'], stdout=devnull)
        except:
            sys.exit("Could not find gpg-error-config.  " +
                     "Please install the libgpg-error development package.")

        gpg_error_content = self._read_header(
            "gpg-error.h", getconfig("cflags", config=gpg_error_config))

        filter_re = re.compile(r'GPG_ERR_[^ ]* =')
        rewrite_re = re.compile(r' *(.*) = .*')

        errors_i_content = ''
        for line in gpg_error_content.splitlines():
            if not filter_re.search(line):
                continue
            errors_i_content += rewrite_re.sub(
                r'%constant long \1 = \1;' + '\n', line.strip())

        self._write_if_unchanged(
            self._in_build_base("errors.i"), errors_i_content)

    def _in_build_base(self, name):
        return os.path.join(self.build_base, name)

    def _generate(self):
        # Cleanup gpgme.h from deprecated functions and typedefs.
        if not os.path.exists(self.build_base):
            os.makedirs(self.build_base)

        self._generate_gpgme_h(gpgme_h, self._in_build_base("gpgme.h"))
        self._generate_errors_i()

        # Copy due to http://bugs.python.org/issue2624
        # Avoid creating in srcdir
        for source, target in ((in_srcdir(n), self._in_build_base(n))
                               for n in ('gpgme.i', 'helpers.c', 'private.h',
                                         'helpers.h')):
            if not up_to_date(source, target):
                shutil.copy2(source, target)

        # Append generated files via build_base
        if not os.path.exists(os.path.join(self.build_lib, "gpg")):
            os.makedirs(os.path.join(self.build_lib, "gpg"))
        shutil.copy2("version.py", os.path.join(self.build_lib, "gpg"))

    def run(self):
        self._generate()

        swig_sources.extend((self._in_build_base('gpgme.i'),
                             self._in_build_base('helpers.c')))
        swig_opts.extend([
            '-I' + self.build_base, '-outdir',
            os.path.join(self.build_lib, 'gpg')
        ])
        include_dirs.insert(0, self.build_base)

        self.run_command('build_ext')
        build.run(self)


py3 = [] if sys.version_info.major < 3 else ['-py3']
swig_sources = []
swig_opts = ['-threads'] + py3 + extra_swig_opts
swige = Extension(
    "gpg._gpgme",
    sources=swig_sources,
    swig_opts=swig_opts,
    include_dirs=include_dirs,
    define_macros=define_macros,
    library_dirs=library_dirs,
    extra_link_args=libs)

setup(
    name="gpg",
    cmdclass={'build': BuildExtFirstHack},
    version="@VERSION@",
    description='Python bindings for GPGME GnuPG cryptography library',
    # TODO: add a long description
    # long_description=long_description,
    author='The GnuPG hackers',
    author_email='gnupg-devel@gnupg.org',
    url='https://www.gnupg.org',
    ext_modules=[swige],
    packages=[
        'gpg', 'gpg.constants', 'gpg.constants.data', 'gpg.constants.keylist',
        'gpg.constants.sig', 'gpg.constants.tofu'
    ],
    license="LGPL2.1+ (the library), GPL2+ (tests and examples)",
    classifiers=[
        'Development Status :: 4 - Beta',
        'Intended Audience :: Developers',
        'License :: OSI Approved :: GNU Lesser General Public License v2 or later (LGPLv2+)',
        'Programming Language :: Python :: 2',
        'Programming Language :: Python :: 2.7',
        'Programming Language :: Python :: 3',
        'Programming Language :: Python :: 3.4',
        'Programming Language :: Python :: 3.5',
        'Programming Language :: Python :: 3.6',
        'Programming Language :: Python :: 3.7',
        'Operating System :: POSIX',
        'Operating System :: Microsoft :: Windows',
        'Topic :: Communications :: Email',
        'Topic :: Security :: Cryptography',
    ],
)
