#from django.shortcuts import render
from django.http import JsonResponse
from django.core.exceptions import ValidationError
from django.contrib.auth.views import login_required

from whoisdb.models import ASBlock, ASNumber, InetNum

@login_required
def asblockFreeAS(request):

	ret = {
		"success": False,
		"errorMsg": None,
		"number": -1,
	}

	try:
		blockName = request.GET.get('block', None)
		if not blockName:
			raise ValidationError("No block given")

		try:
			mnts = request.user.maintainer_set.all()
			block = ASBlock.objects.filter(mnt_by__in=mnts).distinct().get(handle=blockName)
			if block.asblock_set.count() > 0:
				raise ValidationError("AS Block already has sub AS Blocks")
			if block.asnumber_set.count() > 0:
				num = block.asnumber_set.order_by("-number")[0].number + 1
				if num > block.asEnd:
					num = None
					for n in range(block.asBegin, block.asEnd+1):
						try:
							ASNumber.objects.get(number=n)
						except ASNumber.DoesNotExist:
							num = n
							break
					if not num:
						raise ValidationError("No free AS Number in block")
				ret["number"] = num
			else:
				ret["number"] = block.asBegin
		except ASBlock.DoesNotExist:
			raise ValidationError("Could not get AS Block")

		ret["success"] = True
	except ValidationError as e:
		ret["errorMsg"] = e.message
	return JsonResponse(ret)
@login_required
def freeSubnet(request):

	ret = {
		"success": False,
		"errorMsg": None,
		"network": None,
	}
		

	try:
		parentRangeName = request.GET.get('parentRange', None)
		if not parentRangeName:
			raise ValidationError("No subnet given")

		parentRange = None
		try:
			mnts = request.user.maintainer_set.all()
			parentRange = InetNum.objects.filter(mnt_by__in=mnts).distinct().get(handle=parentRangeName)
		except InetNum.DoesNotExist:
			raise ValidationError("Parent range does not exist / is not maintained by you")

		prefixLen = 0
		try:
			prefixLen = int(request.GET.get("prefixLen", 27))
			if prefixLen < 8 or \
				(parentRange.protocol == InetNum.IPv4 and prefixLen > 32) or \
				(parentRange.protocol == InetNum.IPv6 and prefixLen > 128):
				raise ValidationError("Given prefix length is out of range")
		except ValueError:
			raise ValidationError("PrefixLen is not a number")
		nets = list(parentRange.getNetwork().subnets())
		for subRange in parentRange.inetnum_set.all():
			newNet = None
			for net in nets:
				if subRange.getNetwork().network_address in net:
					newNet = net
			if not newNet:
				# critical error, we want a 500 here
				raise ValueError("Subnet not in range")

			nets.remove(newNet)
			nets.extend(newNet.address_exclude(subRange.getNetwork()))

		nets = sorted(nets)
		usableNet = None
		for net in nets:
			if net.prefixlen <= prefixLen:
				usableNet = net
				break

		if not usableNet:
			raise ValidationError("No space left in given range")

		ret["network"] = "%s/%s" % (usableNet.network_address, prefixLen)
		ret["success"] = True
	except ValidationError as e:
		ret["errorMsg"] = e.message
	return JsonResponse(ret)