from datetime import datetime

from django.core.management.base import BaseCommand
from django.utils import timezone

from opennebula.models import VM as VMModel
from uncloud_vm.models import VMHost, VMProduct, VMNetworkCard, VMDiskImageProduct, VMDiskProduct
from uncloud_pay.models import Order


def convert_mac_to_int(mac_address: str):
    # Remove octet connecting characters
    mac_address = mac_address.replace(':', '')
    mac_address = mac_address.replace('.', '')
    mac_address = mac_address.replace('-', '')
    mac_address = mac_address.replace(' ', '')

    # Parse the resulting number as hexadecimal
    mac_address = int(mac_address, base=16)

    return mac_address


def get_vm_price(core, ram, storage, n_of_ipv4, n_of_ipv6):
    storage = storage / 10  # Division by 10 because our base storage unit is 10 GB
    total = 3 * core + 4 * ram + 3.5 * storage + 8 * n_of_ipv4 + 0 * n_of_ipv6

    # TODO: Find some reason about the following magical subtraction.
    total -= 8

    return total


def create_nics(one_vm, vm_product):
    for nic in one_vm.nics:
        mac_address = convert_mac_to_int(nic.get('MAC'))
        ip_address = nic.get('IP', None) or nic.get('IP6_GLOBAL', None)

        VMNetworkCard.objects.update_or_create(
            mac_address=mac_address, vm=vm_product, defaults={'ip_address': ip_address}
        )


def create_disk_and_image(one_vm, vm_product):
    for disk in one_vm.disks:
        owner = one_vm.owner
        name = disk.get('image')

        # TODO: Fix the following hard coded values
        is_os_image, is_public, status = True, True, 'active'

        image_size_in_gb = disk.get('image_size_in_gb')
        disk_size_in_gb = disk.get('size_in_gb')
        storage_class = disk.get('pool_name')
        image_source = disk.get('source')
        image_source_type = disk.get('source_type')

        image, _ = VMDiskImageProduct.objects.update_or_create(
            name=name,
            defaults={
                'owner': owner,
                'is_os_image': is_os_image,
                'is_public': is_public,
                'size_in_gb': image_size_in_gb,
                'storage_class': storage_class,
                'image_source': image_source,
                'image_source_type': image_source_type,
                'status': status
            }
        )
        VMDiskProduct.objects.update_or_create(
            owner=owner, vm=vm_product,
            defaults={
                'image': image,
                'size_in_gb': disk_size_in_gb
            }
        )


class Command(BaseCommand):
    help = 'Migrate Opennebula VM to regular (uncloud) vm'

    def handle(self, *args, **options):
        for one_vm in VMModel.objects.all():
            # Host on which the VM is currently residing
            host = VMHost.objects.filter(vms__icontains=one_vm.vmid).first()

            # VCPU, RAM, Owner, Status
            # TODO: Set actual status instead of hard coded 'active'
            vm_id, cores, ram_in_gb = one_vm.vmid, one_vm.cores, one_vm.ram_in_gb
            owner, status = one_vm.owner, 'active'

            # Total Amount of SSD Storage
            # TODO: What would happen if the attached storage is not SSD but HDD?
            total_storage_in_gb = sum([disk['size_in_gb'] for disk in one_vm.disks])

            # List of IPv4 addresses and Global IPv6 addresses
            ipv4, ipv6 = one_vm.ips

            # TODO: Insert actual/real creation_date, starting_date, ending_date
            #       instead of pseudo one we are putting currently
            creation_date = starting_date = ending_date = datetime.now(tz=timezone.utc)

            # Price calculation

            # TODO: Make the following non-hardcoded
            one_time_price = 0
            recurring_period = 'per_month'

            recurring_price = get_vm_price(cores, ram_in_gb, total_storage_in_gb, len(ipv4), len(ipv6))
            try:
                vm_product = VMProduct.objects.get(vmid=vm_id)
            except VMProduct.DoesNotExist:
                order = Order.objects.create(
                    owner=one_vm.owner,
                    creation_date=creation_date,
                    starting_date=starting_date,
                    ending_date=ending_date,
                    one_time_price=one_time_price,
                    recurring_price=recurring_price,
                    recurring_period=recurring_period
                )
                vm_product, _ = VMProduct.objects.update_or_create(
                    vmid=vm_id,
                    defaults={
                        'cores': cores,
                        'ram_in_gb': ram_in_gb,
                        'owner': owner,
                        'vmhost': host,
                        'order': order,
                        'status': status
                    }
                )

            # Create VMNetworkCards
            create_nics(one_vm, vm_product)

            # Create VMDiskImageProduct and VMDiskProduct
            create_disk_and_image(one_vm, vm_product)