#!/usr/bin/python
#
# Authors:
#   Rob Crittenden <rcritten@redhat.com>
#
# Copyright (C) 2011  Red Hat
# see file 'COPYING' for use and warranty information
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

"""
Generate a custom certificate used in the service unit tests. The certificate
will be created in ipatests/test_xmlrpc/service.crt
"""
import sys
import os
import tempfile
import shutil
import nss.nss as nss
from ipalib import api, x509, backend, errors
from ipaserver.plugins import rabase
from ipapython import ipautil
from ipapython.dn import DN

CERTPATH = 'ipatests/test_xmlrpc/service.crt'

def run_certutil(reqdir, args, stdin=None):
    """
    Run an NSS certutil command
    """
    new_args = ["/usr/bin/certutil", "-d", reqdir]
    new_args = new_args + args
    return ipautil.run(new_args, stdin)

def generateCSR(reqdir, pwname, subject):
    """
    Create a CSR for the given subject.
    """
    run_certutil(reqdir, ["-R", "-s", subject,
                       "-o", '%s/req' % reqdir,
                       "-z", "/etc/group",
                       "-f", pwname,
                       "-a",
                       ])
    fp = open('%s/req' % reqdir, "r")
    data = fp.read()
    fp.close()
    return data

class client(backend.Executioner):
    """
    A simple-minded IPA client that can execute remote commands.
    """

    def run(self, method, *args, **options):
        self.create_context()
        result = self.execute(method, *args, **options)
        return result


def makecert(reqdir):
    """
    Generate a service certificate that can be used during unit testing.
    """
    cfg = dict(
        context='cli',
        in_server=False,
        debug=False,
        verbose=0,
    )

    api.bootstrap(**cfg)
    api.register(client)
    api.finalize()

    ra = rabase.rabase()
    if not os.path.exists(ra.sec_dir) and api.env.xmlrpc_uri == 'http://localhost:8888/ipa/xml':
        sys.exit('The in-tree self-signed CA is not configured, see ipatests/test_xmlrpc/test_cert.py')

    pwname = reqdir + "/pwd"

    # Create an empty password file
    fp = open(pwname, "w")
    fp.write("\n")
    fp.close()

    # Generate NSS cert database to store the private key for our CSR
    run_certutil(reqdir, ["-N", "-f", pwname])

    res = api.Backend.client.run('config_show')
    subject_base = res['result']['ipacertificatesubjectbase'][0]

    cert = None
    subject = DN(('CN', api.env.host), subject_base)
    princ = 'unittest/%s@%s' % (api.env.host, api.env.realm)
    csr = unicode(generateCSR(reqdir, pwname, str(subject)))

    try:
        res = api.Backend.client.run('cert_request', csr, principal=princ,
            add=True)
        cert = x509.make_pem(res['result']['certificate'])
        fd = open(CERTPATH, 'w')
        fd.write(cert)
        fd.close()
    except errors.NotFound:
        return "certificate request failed"
    except errors.CommandError:
        return "You need to set enable_ra=True in ~/.ipa/default.conf"

    nss.nss_init_nodb()
    c = x509.load_certificate(cert, x509.PEM)
    print c

    return 0

reqdir = None

if os.path.exists(CERTPATH):
    print "Test certificate %s exists, skipping." % CERTPATH
    sys.exit(0)
try:
    reqdir = tempfile.mkdtemp(prefix = "tmp-")
    sys.exit(makecert(reqdir))
finally:
    shutil.rmtree(reqdir)