#!/usr/bin/env python3
# -*- coding: utf-8 -*-
#
# Copyright (C) 2015 GNS3 Technologies Inc.
#
# 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/>.

import locale
import re
import os
import sys
import time
import subprocess
import configparser
from json import loads as convert
import urllib.request
from dialog import Dialog, PythonDialogBug

try:
    locale.setlocale(locale.LC_ALL, '')
except locale.Error:
    # Not supported via SSH
    pass

def get_ip():
    """
    Return the active IP
    """
    #request 'ip addr' data in JSON format from shell
    ip_addr_response = subprocess.run(['ip', '--json', 'addr'],capture_output=True)

    #process response, decode and use json.loads to convert the string to a dict
    ip_addr_data = convert(ip_addr_response.stdout.decode("utf-8"))

    #search ip_addr_data for the first ip adress that is not under a virtual bridge or loopback interface
    for i in ip_addr_data:
        if ('virbr' in i['ifname']) or ('lo' in i['ifname']):
            continue
        try:
            if 'UP' in i['flags']:
                ip_addr = i['addr_info'][0]['local']
                break
        except:
            continue
        ip_addr = None
    
    return ip_addr


def get_config():
    """
    Read the config
    """
    config = configparser.RawConfigParser()
    path = os.path.expanduser("~/.config/GNS3/gns3_server.conf")
    config.read([path], encoding="utf-8")
    return config


def write_config(config):
    """
    Write the config file
    """

    with open(os.path.expanduser("~/.config/GNS3/gns3_server.conf"), 'w') as f:
        config.write(f)


def gns3_major_version():
    """
    Returns the GNS3 major server version
    """

    version = gns3_version()
    if version:
        match = re.search(r"\d+.\d+", version)
        return match.group(0)
    return ""


def gns3_version():
    """
    Return the GNS3 server version
    """
    try:
        return subprocess.check_output(["gns3server", "--version"]).strip().decode()
    except (subprocess.CalledProcessError, FileNotFoundError):
        return None


def gns3vm_version():
    """
    Return the GNS3 VM version
    """
    with open('/home/gns3/.config/GNS3/gns3vm_version') as f:
        return f.read().strip()


d = Dialog(dialog="dialog", autowidgetsize=True)
if gns3_version() is None:
    d.set_background_title("GNS3")
else:
    d.set_background_title("GNS3 {}".format(gns3_version()))


def mode():
    if d.yesno("This feature is for testers only. You may break your GNS3 installation. Are you REALLY sure you want to continue?", yes_label="Exit (Safe option)", no_label="Continue") == d.OK:
        return
    code, tag = d.menu("Select the GNS3 version",
                       choices=[("2.1", "Stable release for this GNS3 VM (RECOMMENDED)"),
                                ("2.1dev", "Development version for stable release"),
                                ("2.2", "Latest stable release")])
    d.clear()
    if code == Dialog.OK:
        os.makedirs(os.path.expanduser("~/.config/GNS3"), exist_ok=True)
        with open(os.path.expanduser("~/.config/GNS3/gns3_release"), "w+") as f:
            f.write(tag)

        update(force=True)


def get_release():
    try:
        with open(os.path.expanduser("~/.config/GNS3/gns3_release")) as f:
            content = f.read()

            # Support old VM versions
            if content == "stable":
                content = "1.5"
            elif content == "testing":
                content = "1.5"
            elif content == "unstable":
                content = "1.5dev"

            return content
    except OSError:
        return "1.5"


def update(force=False):
    if not force:
        if d.yesno("PLEASE SNAPSHOT THE VM BEFORE RUNNING THE UPGRADE IN CASE OF FAILURE. The server will reboot at the end of the upgrade process. Continue?") != d.OK:
            return
    release = get_release()
    if release == "2.2":
        if d.yesno("It is recommended to run GNS3 version 2.2 with lastest GNS3 VM based on Ubuntu 18.04 LTS, please download this VM from our website or continue at your own risk!") != d.OK:
            return
    if release.endswith("dev"):
        ret = os.system("curl -Lk https://raw.githubusercontent.com/GNS3/gns3-vm/unstable/scripts/update_{}.sh > /tmp/update.sh && bash -x /tmp/update.sh".format(release))
    else:
        ret = os.system("curl -Lk https://raw.githubusercontent.com/GNS3/gns3-vm/master/scripts/update_{}.sh > /tmp/update.sh && bash -x /tmp/update.sh".format(release))
    if ret != 0:
        print("ERROR DURING UPGRADE PROCESS PLEASE TAKE A SCREENSHOT IF YOU NEED SUPPORT")
        time.sleep(15)


def migrate():
    """
    Migrate GNS3 VM data.
    """

    code, option = d.menu("Select an option",
                          choices=[("Setup", "Configure this VM to send data to another GNS3 VM"),
                                   ("Send", "Send images and projects to another GNS3 VM")])
    d.clear()
    if code == Dialog.OK:
        (answer, destination) = d.inputbox("What is IP address or hostname of the other GNS3 VM?", init="172.16.1.128")
        if answer != d.OK:
            return
        if destination == get_ip():
            d.msgbox("The destination cannot be the same as this VM IP address ({})".format(destination))
            return
        if option == "Send":
            # first make sure they are no files belonging to root
            os.system("sudo chown -R gns3:gns3 /opt/gns3")
            # then rsync the data
            command = r"rsync -az --progress -e 'ssh -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null -i /home/gns3/.ssh/gns3-vm-key' /opt/gns3 gns3@{}:/opt".format(destination)
            ret = os.system('bash -c "{}"'.format(command))
            time.sleep(10)
            if ret != 0:
                d.msgbox("Could not send data to the other GNS3 VM located at {}".format(destination))
            else:
                d.msgbox("Images and projects have been successfully sent to the other GNS3 VM located at {}".format(destination))
        elif option == "Setup":
            script = """
if [ ! -f ~/.ssh/gns3-vm-key ]
then
    ssh-keygen -f ~/.ssh/gns3-vm-key -N '' -C gns3@{}
fi
ssh-copy-id -i ~/.ssh/gns3-vm-key gns3@{}
""".format(get_ip(), destination)
            ret = os.system('bash -c "{}"'.format(script))
            time.sleep(10)
            if ret != 0:
                d.msgbox("Error while setting up the migrate feature")
            else:
                d.msgbox("Configuration successful, you can now send data to the GNS3 VM located at {} without password".format(destination))


def shrink_disk():

    ret = os.system("lspci | grep -i vmware")
    if ret != 0:
        d.msgbox("Shrinking the disk is only supported when running inside VMware")
        return

    if d.yesno("Would you like to shrink the VM disk? The VM will reboot at the end of the process. Continue?") != d.OK:
        return

    os.system("sudo service gns3 stop")
    os.system("sudo service docker stop")
    os.system("sudo vmware-toolbox-cmd disk shrink /opt")
    os.system("sudo vmware-toolbox-cmd disk shrink /")

    d.msgbox("The GNS3 VM will reboot")
    os.execvp("sudo", ['/usr/bin/sudo', "reboot"])

def vm_information():
    """
    Show IP, SSH settings....
    """

    content = "Welcome to GNS3 appliance\n\n"

    version = gns3_version()
    if version is None:
        content += "GNS3 is not installed please install it with sudo pip3 install gns3-server. Or download a preinstalled VM.\n\n"
    else:
        content = "GNS3 version: {gns3_version}\nVM version: {gns3vm_version}\nKVM support available: {kvm}\n\n".format(
            gns3vm_version=gns3vm_version(),
            gns3_version=version,
            kvm=kvm_support())

    ip = get_ip()

    if ip:
        content += "IP: {ip}\n\nTo log in using SSH:\nssh gns3@{ip}\nPassword: gns3\n\nImages and projects are located in /opt/gns3""".format(ip=ip)
    else:
        content += "eth0 is not configured. Please manually configure it via the Networking menu."

    content += "\n\nRelease channel: " + get_release()

    try:
        d.msgbox(content)
    # If it's an scp command or any bugs
    except:
        os.execvp("bash", ['/bin/bash'])


def check_internet_connectivity():
    d.pause("Please wait...\n\n")
    try:
        response = urllib.request.urlopen('http://pypi.python.org/', timeout=5)
    except urllib.request.URLError as err:
        d.infobox("Can't connect to Internet (pypi.python.org): {}".format(str(err)))
        time.sleep(15)
        return
    d.infobox("Connection to Internet: OK")
    time.sleep(2)


def keyboard_configuration():
    """
    Allow user to change the keyboard layout
    """
    os.system("/usr/bin/sudo dpkg-reconfigure keyboard-configuration")


def set_security():
    config = get_config()
    if d.yesno("Enable server authentication?") == d.OK:
        if not config.has_section("Server"):
            config.add_section("Server")
        config.set("Server", "auth", True)
        (answer, text) = d.inputbox("Login?")
        if answer != d.OK:
            return
        config.set("Server", "user", text)
        (answer, text) = d.passwordbox("Password?")
        if answer != d.OK:
            return
        config.set("Server", "password", text)
    else:
        config.set("Server", "auth", False)

    write_config(config)


def log():
    os.system("/usr/bin/sudo chmod 755 /var/log/upstart/gns3.log")
    with open("/var/log/upstart/gns3.log") as f:
        try:
            while True:
                line = f.readline()
                sys.stdout.write(line)
        except (KeyboardInterrupt, MemoryError):
            return


def edit_config():
    """
    Edit GNS3 configuration file
    """

    major_version = gns3_major_version()
    if major_version == "2.2":
        os.system("nano ~/.config/GNS3/{}/gns3_server.conf".format(major_version))
    else:
        os.system("nano ~/.config/GNS3/gns3_server.conf")


def edit_network():
    """
    Edit network configuration file
    """
    if d.yesno("The server will reboot at the end of the process. Continue?") != d.OK:
        return
    os.system("sudo nano /etc/network/interfaces")
    os.execvp("sudo", ['/usr/bin/sudo', "reboot"])


def edit_proxy():
    """
    Configure proxy settings
    """
    res, http_proxy = d.inputbox(text="HTTP proxy string, for example http://<user>:<password>@<proxy>:<port>. Leave empty for no proxy.")
    if res != d.OK:
        return
    res, https_proxy = d.inputbox(text="HTTPS proxy string, for example http://<user>:<password>@<proxy>:<port>. Leave empty for no proxy.")
    if res != d.OK:
        return

    with open('/tmp/00proxy', 'w+') as f:
        f.write('Acquire::http::Proxy "' + http_proxy + '";')
    os.system("sudo mv /tmp/00proxy /etc/apt/apt.conf.d/00proxy")
    os.system("sudo chown root /etc/apt/apt.conf.d/00proxy")
    os.system("sudo chmod 744 /etc/apt/apt.conf.d/00proxy")

    with open('/tmp/proxy.sh', 'w+') as f:
        f.write('export http_proxy="' + http_proxy + '"\n')
        f.write('export https_proxy="' + https_proxy + '"\n')
        f.write('export HTTP_PROXY="' + http_proxy + '"\n')
        f.write('export HTTPS_PROXY="' + https_proxy + '"\n')
    os.system("sudo mv /tmp/proxy.sh /etc/profile.d/proxy.sh")
    os.system("sudo chown root /etc/profile.d/proxy.sh")
    os.system("sudo chmod 744 /etc/profile.d/proxy.sh")
    os.system("sudo cp /etc/profile.d/proxy.sh /etc/default/docker")

    d.msgbox("The GNS3 VM will reboot")
    os.execvp("sudo", ['/usr/bin/sudo', "reboot"])


def kvm_support():
    """
    Returns true if KVM is available
    """
    return subprocess.call("kvm-ok") == 0


def kvm_control():
    """
    Check if KVM is correctly configured
    """

    kvm_ok = kvm_support()
    config = get_config()
    try:
        if config.getboolean("Qemu", "enable_kvm") is True:
            if kvm_ok is False:
                if d.yesno("KVM is not available!\n\nQemu VM will crash!!\n\nThe reason could be unsupported hardware or another virtualization solution is already running.\n\nDisable KVM and get lower performances?") == d.OK:
                    config.set("Qemu", "enable_kvm", False)
                    write_config(config)
                    os.execvp("sudo", ['/usr/bin/sudo', "reboot"])
        else:
            if kvm_ok is True:
                if d.yesno("KVM is available on your computer.\n\nEnable KVM and get better performances?") == d.OK:
                    config.set("Qemu", "enable_kvm", True)
                    write_config(config)
                    os.execvp("sudo", ['/usr/bin/sudo', "reboot"])
    except configparser.NoSectionError:
        return


vm_information()
kvm_control()


try:
    while True:
        code, tag = d.menu("GNS3 {}".format(gns3_version()),
                           choices=[("Information", "Display VM information"),
                            ("Upgrade", "Upgrade GNS3"),
                            ("Migrate", "Migrate data to another GNS3 VM"),
                            ("Shell", "Open a console"),
                            ("Security", "Configure authentication"),
                            ("Keyboard", "Change keyboard layout"),
                            ("Configure", "Edit server configuration (advanced users ONLY)"),
                            ("Proxy", "Configure proxy settings"),
                            ("Networking", "Configure networking settings"),
                            ("Log", "Show server log"),
                            ("Test", "Check internet connection"),
                            ("Shrink", "Shrink the VM disk"),
                            ("Version", "Select the GNS3 version"),
                            ("Restore", "Restore the VM (if you have trouble for upgrade)"),
                            ("Reboot", "Reboot the VM"),
                            ("Shutdown", "Shutdown the VM")])
        d.clear()
        if code == Dialog.OK:
            if tag == "Shell":
                os.execvp("bash", ['/bin/bash'])
            elif tag == "Version":
                mode()
            elif tag == "Restore":
                os.execvp("sudo", ['/usr/bin/sudo', "/usr/local/bin/gns3restore"])
            elif tag == "Reboot":
                os.execvp("sudo", ['/usr/bin/sudo', "reboot"])
            elif tag == "Shutdown":
                os.execvp("sudo", ['/usr/bin/sudo', "poweroff"])
            elif tag == "Upgrade":
                update()
            elif tag == "Information":
                vm_information()
            elif tag == "Log":
                log()
            elif tag == "Migrate":
                migrate()
            elif tag == "Configure":
                edit_config()
            elif tag == "Networking":
                edit_network()
            elif tag == "Security":
                set_security()
            elif tag == "Keyboard":
                keyboard_configuration()
            elif tag == "Test":
                check_internet_connectivity()
            elif tag == "Proxy":
                edit_proxy()
            elif tag == "Shrink":
                shrink_disk()
except KeyboardInterrupt:
    sys.exit(0)