#!/usr/bin/env python
"""
Unit-Tests for moznetwork
"""

import re
import subprocess
from distutils.spawn import find_executable
from unittest import mock

import mozinfo
import moznetwork
import mozunit
import pytest


@pytest.fixture(scope="session")
def ip_addresses():
    """List of IP addresses associated with the host."""

    # Regex to match IPv4 addresses.
    # 0-255.0-255.0-255.0-255, note order is important here.
    regexip = re.compile(
        "((25[0-5]|2[0-4]\d|1\d\d|[1-9]\d|\d)\.){3}"
        "(25[0-5]|2[0-4]\d|1\d\d|[1-9]\d|\d)"
    )

    commands = (
        ["ip", "addr", "show"],
        ["ifconfig"],
        ["ipconfig"],
        # Explicitly search '/sbin' because it doesn't always appear
        # to be on the $PATH of all systems
        ["/sbin/ip", "addr", "show"],
        ["/sbin/ifconfig"],
    )

    cmd = None
    for command in commands:
        if find_executable(command[0]):
            cmd = command
            break
    else:
        raise OSError(
            "No program for detecting ip address found! Ensure one of 'ip', "
            "'ifconfig' or 'ipconfig' exists on your $PATH."
        )

    ps = subprocess.Popen(cmd, stdout=subprocess.PIPE)
    standardoutput, _ = ps.communicate()

    # Generate a list of IPs by parsing the output of ip/ifconfig
    return [x.group() for x in re.finditer(regexip, standardoutput.decode("UTF-8"))]


def test_get_ip(ip_addresses):
    """Attempt to test the IP address returned by
    moznetwork.get_ip() is valid"""
    assert moznetwork.get_ip() in ip_addresses


@pytest.mark.skipif(mozinfo.isWin, reason="Test is not supported in Windows")
def test_get_ip_using_get_interface(ip_addresses):
    """Test that the control flow path for get_ip() using
    _get_interface_list() is works"""
    with mock.patch("socket.gethostbyname") as byname:
        # Force socket.gethostbyname to return None
        byname.return_value = None
        assert moznetwork.get_ip() in ip_addresses


if __name__ == "__main__":
    mozunit.main()
