from django.contrib.auth import get_user_model

from rest_framework import serializers

from .models import *
from uncloud_pay.models import RecurringPeriod, BillingAddress

# XXX: does not seem to be used?

GB_SSD_PER_DAY=0.012
GB_HDD_PER_DAY=0.0006

GB_SSD_PER_DAY=0.012
GB_HDD_PER_DAY=0.0006

###
# Admin views.

class VMHostSerializer(serializers.HyperlinkedModelSerializer):
    vms = serializers.PrimaryKeyRelatedField(many=True, read_only=True)

    class Meta:
        model = VMHost
        fields = '__all__'
        read_only_fields = [ 'vms' ]

class VMClusterSerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = VMCluster
        fields = '__all__'


###
# Disks.

class VMDiskProductSerializer(serializers.ModelSerializer):
    class Meta:
        model = VMDiskProduct
        fields = '__all__'

class CreateVMDiskProductSerializer(serializers.ModelSerializer):
    class Meta:
        model = VMDiskProduct
        fields = ['size_in_gb', 'image']

class CreateManagedVMDiskProductSerializer(serializers.ModelSerializer):
    class Meta:
        model = VMDiskProduct
        fields = ['size_in_gb']

class VMDiskImageProductSerializer(serializers.ModelSerializer):
    class Meta:
        model = VMDiskImageProduct
        fields = '__all__'

class VMSnapshotProductSerializer(serializers.ModelSerializer):
    class Meta:
        model = VMSnapshotProduct
        fields = '__all__'


    # verify that vm.owner == user.request
    def validate_vm(self, value):
        if not value.owner == self.context['request'].user:
            raise serializers.ValidationError("VM {} not found for owner {}.".format(value,
                                                                                     self.context['request'].user))
        disks = VMDiskProduct.objects.filter(vm=value)

        if len(disks) == 0:
            raise serializers.ValidationError("VM {} does not have any disks, cannot snapshot".format(value.id))

        return value

    pricing = {}
    pricing['per_gb_ssd'] = 0.012
    pricing['per_gb_hdd'] = 0.0006
    pricing['recurring_period'] = 'per_day'

###
# VMs

# Helper used in uncloud_service for services allocating VM.
class ManagedVMProductSerializer(serializers.ModelSerializer):
    """
    Managed VM serializer used in ungleich_service app.
    """
    primary_disk = CreateManagedVMDiskProductSerializer()
    class Meta:
        model = VMWithOSProduct
        fields = [ 'cores', 'ram_in_gb', 'primary_disk']

class VMProductSerializer(serializers.ModelSerializer):
    primary_disk = CreateVMDiskProductSerializer()
    snapshots = VMSnapshotProductSerializer(many=True, read_only=True)
    disks = VMDiskProductSerializer(many=True, read_only=True)

    class Meta:
        model = VMWithOSProduct
        fields = ['order', 'owner', 'status', 'name', 'cores',
                'ram_in_gb', 'primary_disk', 'snapshots', 'disks', 'extra_data']
        read_only_fields = ['order', 'owner', 'status']

class OrderVMProductSerializer(VMProductSerializer):
    recurring_period = serializers.ChoiceField(
            choices=VMWithOSProduct.allowed_recurring_periods())

    def __init__(self, *args, **kwargs):
        super(VMProductSerializer, self).__init__(*args, **kwargs)

    class Meta:
        model = VMProductSerializer.Meta.model
        fields = VMProductSerializer.Meta.fields + [ 'recurring_period' ]
        read_only_fields = VMProductSerializer.Meta.read_only_fields

# Nico's playground.
class NicoVMProductSerializer(serializers.ModelSerializer):
    snapshots = VMSnapshotProductSerializer(many=True, read_only=True)
    order = serializers.StringRelatedField()

    class Meta:
        model = VMProduct
        read_only_fields = ['order', 'owner', 'status',
                            'vmhost', 'vmcluster', 'snapshots',
                            'extra_data' ]
        fields = read_only_fields + [ 'name',
                                      'cores',
                                      'ram_in_gb'
        ]

class DCLVMProductSerializer(serializers.HyperlinkedModelSerializer):
    """
    Create an interface similar to standard DCL
    """

    # Custom field used at creation (= ordering) only.
    recurring_period = serializers.ChoiceField(
        choices=VMProduct.allowed_recurring_periods())

    os_disk_uuid = serializers.UUIDField()
    # os_disk_size =

    class Meta:
        model = VMProduct