#!/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: vyos-show-version
# Purpose:
#    Displays image version and system information.
#    Used by the "run show version" command.


import sys
import subprocess
import json

import pystache


def read_file(name):
    with open (name, "r") as f:
        data = f.read()
    return data.strip()

version_file = '/opt/vyatta/etc/version.json'
version_data = None

version_output_tmpl = """
Version:          VyOS {{version}}
Built by:         {{built_by}}
Built on:         {{built_on}}
Build ID:         {{build_id}}

Architecture:     {{system_arch}}
Boot via:         {{boot_via}}
System type:      {{system_type}}

Hardware vendor:  {{hardware_vendor}}
Hardware model:   {{hardware_model}}
Hardware S/N:     {{hardware_serial}}
Hardware UUID:    {{hardware_uuid}}

Copyright:        VyOS maintainers and contributors

"""

# Get and display image version data from the built-in version file
# This gives us image version, built on, build by, and build UUID
try:
    with open(version_file, 'r') as f:
        version_data = json.load(f)
except:
    print("Unable to get VyOS version data")
    sys.exit(1)


# Get system architecture (well, kernel architecture rather)
version_data['system_arch'] = subprocess.check_output('uname -m', shell=True).strip()


# Get hypervisor name, if any
system_type = "physical"
try:
    hypervisor = subprocess.check_output('hvinfo', shell=True).strip()
    system_type = "{0} guest".format(hypervisor)
except subprocess.CalledProcessError:
    # hvinfo returns 1 if it cannot detect any hypervisor
    pass
version_data['system_type'] = system_type


# Get boot type, it can be livecd, installed image, or, possible, a system installed
# via legacy "install system" mechanism
# In installed images, the squashfs image file is named after its image version,
# while on livecd it's just "filesystem.squashfs", that's how we tell a livecd boot
# from an installed image
boot_via = "installed image"
if subprocess.call(""" grep -e '^overlay.*/filesystem.squashfs' /proc/mounts >/dev/null""", shell=True) == 0:
    boot_via = "livecd"
elif subprocess.call(""" grep '^overlay /' /proc/mounts >/dev/null """, shell=True) != 0:
    boot_via = "legacy non-image installation"
version_data['boot_via'] = boot_via
    

# Get hardware details from DMI
version_data['hardware_vendor'] = read_file('/sys/class/dmi/id/sys_vendor')
version_data['hardware_model']  = read_file('/sys/class/dmi/id/product_name')
# XXX: serial and uuid files are only readable for root, so we cannot just read them
#      when script is ran by a normal user, hence this ugly fixup
version_data['hardware_serial'] = subprocess.check_output('sudo cat /sys/class/dmi/id/subsystem/id/product_serial', shell=True).strip()
version_data['hardware_uuid'] = subprocess.check_output('sudo cat /sys/class/dmi/id/subsystem/id/product_uuid', shell=True).strip()


output = pystache.render(version_output_tmpl, version_data).strip()
print(output)