#!/usr/bin/env python
#
# Copyright (C) 2016 VyOS maintainers and contributors
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2 or later as
# published by the Free Software Foundation.
#
# 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/>.
#
# File: check-vm-build-env
# Purpose:
#   Checks if packages required for VM image build are installed.


import os
import sys
from distutils.spawn import find_executable

required_packages = [
    'make',
    'qemu-system-x86',
    'qemu-utils'
]


def is_installed(name):
    result = os.system("dpkg-query -W --showformat='${{Status}}\n' {name} 2>&1 | grep 'install ok installed' >/dev/null".format(name=name))
    return True if result == 0 else False


missing_packages = []

print("Checking if packages required for VyOS VM image build are installed")

for p in required_packages:
    if not is_installed(p):
        missing_packages.append(p)

if missing_packages:
    print("Your system does not have some of the required packages installed.")
    print("Please install the following packages:")
    print(" ".join(missing_packages))
    sys.exit(1)
else:
    print("All required packages are installed")

if find_executable("packer"):
    print("Your system has Packer.")
else:
    print("Your system does not have Packer.")
    print("Please install Packer from https://www.packer.io/downloads.html.")
    sys.exit(1)

sys.exit(0)