from django.shortcuts import render, get_object_or_404, redirect
from django.http import HttpResponse
from django.contrib.auth.forms import AuthenticationForm
from django.db.models import Q
from django.views.decorators.csrf import csrf_exempt
from django.utils import timezone
from django.core.files import File
from django.db.models.fields.files import FieldFile
from .models import Device, Organization, Network

from distutils.dir_util import copy_tree

import glob
import sys
import subprocess
import os
import socket
import tempfile
import crypt
import tarfile

def index(request):
    if request.user.is_authenticated:
        return redirect("/devices")
    else:
        return redirect("/accounts/login")

@csrf_exempt
def heartbeat(request):
    device = get_object_or_404(Device, secret=request.POST.get("secret", ""))
    ip = request.POST.get("ip", "")
    if ip:
        device.lasttime = timezone.now()
        if device.curip:
            device.curip = ip or device.curip
        else:
            device.curip = ip

    device.save()
    return HttpResponse("reboot" if device.reboot else "")

@csrf_exempt
def hosts(request):
    device = get_object_or_404(Device, secret=request.POST.get("secret", ""))
    device.reboot = False
    device.save()
    return render(request, "manager/hosts", {"device": device})

def ping(request, device_id):
    if request.user.is_authenticated:
        device = None
        ajax = '{\n "status": '

        for organization in Organization.objects.filter(users=request.user):
            device = device or Device.objects.filter(id=device_id, organization=organization)

        if not device:
            ajax += "-1"

        else:
            try:
                socket.inet_aton(device[0].curip)
                ajax += str(int(not os.WEXITSTATUS(os.system("ping -c1 -w1 " + device[0].curip + " > /dev/null 2>&1")))) # This monster is not long enough yet.
                ajax += ',\n "ip": "%s"' % device[0].curip
                ajax += ',\n "time": "%s"' % device[0].lasttime

            except:
                ajax += "-3"

    else:
        ajax += "-2"

    ajax += "\n}"
    return HttpResponse(ajax)
    
def devices(request):
    if request.user.is_authenticated:
        user = request.user
        devices = set()
        orga = None

        for organization in Organization.objects.filter(users=user):
            orga = orga or organization
            for device in Device.objects.filter(organization=organization):
                devices.add(device)

        return render(request, "manager/index.html",
                {
                    "title": "Device Administration",
                    "user": user,
                    "organization": orga,
                    "devices": devices
                    }
                )
    else:
        return redirect("/")

def editdevice(request, device_id):
    if request.user.is_authenticated:
       device = None
       subnets = set()
       for organization in Organization.objects.filter(users=request.user):
          device = device or Device.objects.filter(id=device_id, organization=organization)
          for subnet in Network.objects.filter(organizations=organization):
              subnets.add(subnet)

       if not device:
           return redirect("/")

       if request.POST.get("subnet", ""):
           subnet = Network.objects.filter(intip=request.POST.get("subnet", device[0].network.intip))

           if subnet[0] in subnets:
            device[0].name = request.POST.get("name", "")
            device[0].network = subnet[0]
            device[0].reboot = True if request.POST.get("reboot", "0") == "True" else False
            device[0].save()

            return redirect("/")

       return render(request, "manager/edit.html",
                {
                    "title": "Edit Device",
                    "device": device[0],
                    "subnets": subnets
                    }
                )

    else:
        return redirect("/")

def getconfig(request, device_id):
    BEFORE = os.getcwd()
    DEVICEDIR = "/opt/vpnmanager/device-config/"
    SRCDIR = "/opt/openwrt/"

    if not request.user.is_superuser:
        return redirect("/")

    device = get_object_or_404(Device, id=device_id)

    tempdir = tempfile.TemporaryDirectory()

    copy_tree(DEVICEDIR, tempdir.name)
    
    # Write OpenVPN config

    with open(tempdir.name + "/etc/openvpn/client.conf", "w") as vpnconf:
        vpnconf.write(device.vpnconfig)

    # Write secret

    with open(tempdir.name + "/etc/vpnsecret", "w") as secret:
        secret.write('SECRET="%s"' % device.secret)

    # Write password

    with open(tempdir.name + "/etc/shadow", "r") as shadow: 
        password = crypt.crypt(device.password, crypt.mksalt(crypt.METHOD_MD5))
        shadowin = shadow.read()

    with open(tempdir.name + "/etc/shadow", "w") as shadowout:
        shadowout.write(shadowin.replace("$PASSWORD", password))

    # Write SSID

    with open(tempdir.name + "/etc/config/wireless", "r") as wireless:
        wirein = wireless.read()

    with open(tempdir.name + "/etc/config/wireless", "w") as wireout:
        wireout.write(wirein.replace("$SSID", device.serial))

    '''
    # Generate .tar.gz file

    with tarfile.open(tempdir.name + ".tar.gz", "w:gz") as tar:
        tar.add(tempdir.name, arcname=os.path.sep)

    with open(tempdir.name + ".tar.gz", "rb") as download:
        response = HttpResponse(download.read(), content_type="application/tar+gzip")
        response['Content-Disposition'] = 'inline; filename=' + os.path.basename(device.serial + ".tar.gz")
        return response
    '''

    # Create compilation environment

    os.system("rm -rf " + SRCDIR + "/files/")
    os.mkdir(SRCDIR + "/files/")
    os.system("cp -r " + tempdir.name + "/* " + SRCDIR + "/files/")

    tempdir.cleanup()

    os.system("rm " + SRCDIR + "/bin/targets/ar71xx/generic/*")

    # Build image

    os.chdir(SRCDIR)

    try:
        output = subprocess.check_output(["make", "-j9"])
    except:
        os.chdir(BEFORE)
        return HttpResponse("Something went wrong building the image file.\n\n" + output)
    
    os.chdir(BEFORE)

    with open(glob.glob(SRCDIR + "/bin/targets/ar71xx/generic/*squashfs-sysupgrade.bin")[0], "rb") as download:
        response = HttpResponse(download.read(), content_type="application/octet-stream")
        response['Content-Disposition'] = 'inline; filename=' + os.path.basename(device.serial + ".bin")
        os.system("rm -rf " + SRCDIR + "/files/")
        os.system("rm " + SRCDIR + "/bin/targets/ar71xx/generic/*")
        return response

def rebootdevice(request, device_id):
    if request.user.is_authenticated:
       device = None
       for organization in Organization.objects.filter(users=request.user):
          device = device or Device.objects.filter(id=device_id, organization=organization)

       if not device:
           return redirect("/")

       device[0].reboot = True
       device[0].save()

       return redirect("/")

def deletedevice(request, device_id):
    if request.user.is_superuser:
        device = get_object_or_404(Device, id=device_id)
        device.delete()

    return redirect("/")

def makedevice(request):
   CADIR = "/etc/openvpn/ca/"
   CONFIGDIR = "/etc/openvpn/client-configs/"
   BEFORE = os.getcwd()

   device_serial = request.POST.get("serial", "")
   device_name = request.POST.get("name", "")
   device_organization = request.POST.get("organization", "")

   if not request.user.is_superuser:
        return redirect("/")

   if not device_serial:
        orga = Organization.objects.all()
   
        return render(request, "manager/add.html",
                {
                    "title": "Add Device",
                    "organizations": orga,
                    }
                )

   if glob.glob(CADIR + "/keys/" + device_serial + "*"):
        return HttpResponse("This key already exists.")

   os.chdir(CADIR)

   if subprocess.call(CADIR + "/generate-key " + device_serial, shell=True):
        return HttpResponse("Something went wrong trying to generate the key.")

   if glob.glob(CONFIGDIR + "/files/" + device_serial + "*"):
       return HttpResponse("This configuration file already exists.")

   os.chdir(CONFIGDIR)

   if subprocess.call(CONFIGDIR + "/make_config " + device_serial, shell=True):
       return HttpResponse("Something went wrong trying to generate the config file.")

   os.chdir(BEFORE)

   device = Device.objects.create(
           serial=device_serial,
           name=device_name,
           network=Network.objects.filter(intip="No VPN")[0],
           organization=Organization.objects.filter(id=device_organization)[0],
           vpnconfig = open(CONFIGDIR + "/files/" + device_serial + ".ovpn").read()
           )

   return redirect("/")