#!/usr/bin/env python3

"""
This script launches a dbus session, sets the DBUS_SESSION_BUS_ADDRESS
and DBUS_STARTER_BUS_TYPE Eenvironment variables and puts the generated files
in the dbus dir location passed as a parameter. It then runs the unit test
script, and then cleans up the generated dbus files.
"""

import argparse
import os
import re
import sys
import tempfile
from subprocess import check_call, check_output


def launch_session_dbus(dbus_dir, dbus_config_file):
    """
    Launches a session debus using a modified config file and
    sets the DBUS_SESSION_BUS_ADDRESS environment variable

    Parameter descriptions:
    dbus_dir            Directory location for generated files
    dbus_config_file    File location of dbus sys config file
    """
    dbus_pid = os.path.join(dbus_dir, "pid")
    dbus_socket = os.path.join(dbus_dir, "system_bus_socket")
    dbus_local_conf = os.path.join(dbus_dir, "system-local.conf")
    if os.path.isfile(dbus_pid):
        os.remove(dbus_pid)
    with open(dbus_config_file) as infile, open(
        dbus_local_conf, "w"
    ) as outfile:
        for line in infile:
            line = re.sub(
                "<type>.*</type>",
                "<type>session</type>",
                line,
                flags=re.DOTALL,
            )
            line = re.sub(
                "<pidfile>.*</pidfile>",
                "<pidfile>%s</pidfile>" % dbus_pid,
                line,
                flags=re.DOTALL,
            )
            line = re.sub(
                "<listen>.*</listen>",
                "<listen>unix:path=%s</listen>" % dbus_socket,
                line,
                flags=re.DOTALL,
            )
            line = re.sub("<deny", "<allow", line)
            outfile.write(line)
    infile.close()
    outfile.close()
    command = [
        "dbus-daemon",
        "--config-file=%s" % dbus_local_conf,
        "--print-address",
    ]
    out = check_output(command).splitlines()
    os.environ["DBUS_SESSION_BUS_ADDRESS"] = out[0].decode("utf-8")
    os.environ["DBUS_STARTER_BUS_TYPE"] = "session"


def dbus_cleanup(dbus_dir):
    """
    Kills the dbus session started by launch_session_dbus

    Parameter descriptions:
    dbus_dir            Directory location of generated files
    """

    dbus_pid = os.path.join(dbus_dir, "pid")
    if os.path.isfile(dbus_pid):
        dbus_pid = open(dbus_pid, "r").read().replace("\n", "")
        check_call(["kill", dbus_pid])


if __name__ == "__main__":
    # Set command line arguments
    parser = argparse.ArgumentParser()

    parser.add_argument(
        "-f",
        "--dbussysconfigfile",
        dest="DBUS_SYS_CONFIG_FILE",
        required=True,
        help="Dbus sys config file location",
    )
    parser.add_argument(
        "-u",
        "--unittestandparams",
        dest="UNIT_TEST",
        required=True,
        help=(
            "Unit test script and params                         as comma"
            " delimited string"
        ),
    )
    args = parser.parse_args(sys.argv[1:])
    DBUS_DIR = tempfile.TemporaryDirectory(dir="/tmp/")
    DBUS_SYS_CONFIG_FILE = args.DBUS_SYS_CONFIG_FILE
    UNIT_TEST = args.UNIT_TEST

    launch_session_dbus(DBUS_DIR.name, DBUS_SYS_CONFIG_FILE)
    check_call(UNIT_TEST.split(","), env=os.environ)
    dbus_cleanup(DBUS_DIR.name)