from uuid import uuid4

from django.db import models
from django.db.models import Field
from django.db.models.query import QuerySet

import mptt
from mptt.fields import TreeForeignKey, TreeManyToManyField, TreeOneToOneField
from mptt.managers import TreeManager
from mptt.models import MPTTModel


class CustomTreeQueryset(QuerySet):
    def custom_method(self):
        pass


class CustomTreeManager(TreeManager):
    def get_queryset(self):
        return CustomTreeQueryset(model=self.model, using=self._db)


class Category(MPTTModel):
    name = models.CharField(max_length=50)
    visible = models.BooleanField(default=True)
    parent = TreeForeignKey(
        "self", null=True, blank=True, related_name="children", on_delete=models.CASCADE
    )
    category_uuid = models.CharField(max_length=50, unique=True, null=True)

    def __str__(self):
        return self.name

    def delete(self):
        super().delete()

    delete.alters_data = True


class Item(models.Model):

    name = models.CharField(max_length=100)
    category_fk = models.ForeignKey(
        "Category",
        to_field="category_uuid",
        null=True,
        related_name="items_by_fk",
        on_delete=models.CASCADE,
    )
    category_pk = models.ForeignKey(
        "Category", null=True, related_name="items_by_pk", on_delete=models.CASCADE
    )

    def __str__(self):
        return self.name


class SubItem(models.Model):
    item = models.ForeignKey(Item, null=True, on_delete=models.CASCADE)


class Genre(MPTTModel):
    name = models.CharField(max_length=50, unique=True)
    parent = TreeForeignKey(
        "self", null=True, blank=True, related_name="children", on_delete=models.CASCADE
    )

    def __str__(self):
        return self.name


class Game(models.Model):
    genre = TreeForeignKey(Genre, on_delete=models.CASCADE)
    genres_m2m = models.ManyToManyField(Genre, related_name="games_m2m")
    name = models.CharField(max_length=50)

    def __str__(self):
        return self.name


class Insert(MPTTModel):
    parent = models.ForeignKey(
        "self", null=True, blank=True, related_name="children", on_delete=models.CASCADE
    )


class MultiOrder(MPTTModel):
    name = models.CharField(max_length=50)
    size = models.PositiveIntegerField()
    date = models.DateField()
    parent = TreeForeignKey(
        "self", null=True, blank=True, related_name="children", on_delete=models.CASCADE
    )

    class MPTTMeta:
        order_insertion_by = ["name", "size", "-date"]

    def __str__(self):
        return self.name


class Node(MPTTModel):
    parent = TreeForeignKey(
        "self", null=True, blank=True, related_name="children", on_delete=models.CASCADE
    )
    # To check that you can set level_attr etc to an existing field.
    level = models.IntegerField()

    class MPTTMeta:
        left_attr = "does"
        right_attr = "zis"
        level_attr = "level"
        tree_id_attr = "work"


class UUIDNode(MPTTModel):
    parent = models.ForeignKey(
        "self", null=True, blank=True, related_name="children", on_delete=models.CASCADE
    )
    uuid = models.UUIDField(primary_key=True, default=uuid4)
    name = models.CharField(max_length=50)

    def __str__(self):
        return self.name


class OrderedInsertion(MPTTModel):
    name = models.CharField(max_length=50)
    parent = TreeForeignKey(
        "self", null=True, blank=True, related_name="children", on_delete=models.CASCADE
    )

    class MPTTMeta:
        order_insertion_by = ["name"]

    def __str__(self):
        return self.name


class Tree(MPTTModel):
    parent = TreeForeignKey(
        "self", null=True, blank=True, related_name="children", on_delete=models.CASCADE
    )


class NewStyleMPTTMeta(MPTTModel):
    parent = TreeForeignKey(
        "self", null=True, blank=True, related_name="children", on_delete=models.CASCADE
    )

    class MPTTMeta:
        left_attr = "testing"


class Person(MPTTModel):
    name = models.CharField(max_length=50)
    parent = TreeForeignKey(
        "self", null=True, blank=True, related_name="children", on_delete=models.CASCADE
    )

    # just testing it's actually possible to override the tree manager
    objects = CustomTreeManager()

    def __str__(self):
        return self.name


class Student(Person):
    type = models.CharField(max_length=50)


class CustomPKName(MPTTModel):
    my_id = models.AutoField(db_column="my_custom_name", primary_key=True)
    name = models.CharField(max_length=50)
    parent = TreeForeignKey(
        "self",
        null=True,
        blank=True,
        related_name="children",
        db_column="my_cusom_parent",
        on_delete=models.CASCADE,
    )

    def __str__(self):
        return self.name


class ReferencingModel(models.Model):
    fk = TreeForeignKey(Category, related_name="+", on_delete=models.CASCADE)
    one = TreeOneToOneField(Category, related_name="+", on_delete=models.CASCADE)
    m2m = TreeManyToManyField(Category, related_name="+")


# for testing various types of inheritance:

# 1. multi-table inheritance, with mptt fields on base class.


class MultiTableInheritanceA1(MPTTModel):
    parent = TreeForeignKey(
        "self", null=True, blank=True, related_name="children", on_delete=models.CASCADE
    )


class MultiTableInheritanceA2(MultiTableInheritanceA1):
    name = models.CharField(max_length=50)


# 2. multi-table inheritance, with mptt fields on child class.


class MultiTableInheritanceB1(MPTTModel):
    name = models.CharField(max_length=50)


class MultiTableInheritanceB2(MultiTableInheritanceB1):
    parent = TreeForeignKey(
        "self", null=True, blank=True, related_name="children", on_delete=models.CASCADE
    )


# 3. abstract models


class AbstractModel(MPTTModel):
    parent = TreeForeignKey(
        "self", null=True, blank=True, related_name="children", on_delete=models.CASCADE
    )
    ghosts = models.CharField(max_length=50)

    class Meta:
        abstract = True


class ConcreteModel(AbstractModel):
    name = models.CharField(max_length=50)


class AbstractConcreteAbstract(ConcreteModel):
    # abstract --> concrete --> abstract

    class Meta:
        abstract = True


class ConcreteAbstractConcreteAbstract(ConcreteModel):
    # concrete --> abstract --> concrete --> abstract
    pass


class ConcreteConcrete(ConcreteModel):
    # another subclass (concrete this time) of the root concrete model
    pass


# 4. proxy models


class SingleProxyModel(ConcreteModel):
    objects = CustomTreeManager()

    class Meta:
        proxy = True


class DoubleProxyModel(SingleProxyModel):
    class Meta:
        proxy = True


# 5. swappable models


class SwappableModel(MPTTModel):
    parent = TreeForeignKey(
        "self", null=True, blank=True, related_name="children", on_delete=models.CASCADE
    )

    class Meta:
        swappable = "MPTT_SWAPPABLE_MODEL"


class SwappedInModel(MPTTModel):
    parent = TreeForeignKey(
        "self", null=True, blank=True, related_name="children", on_delete=models.CASCADE
    )
    name = models.CharField(max_length=50)


# Default manager
class MultipleManager(TreeManager):
    def get_queryset(self):
        return super().get_queryset().exclude(published=False)


class MultipleManagerModel(MPTTModel):
    parent = TreeForeignKey(
        "self", null=True, blank=True, related_name="children", on_delete=models.CASCADE
    )
    published = models.BooleanField()

    objects = TreeManager()
    foo_objects = MultipleManager()


class AutoNowDateFieldModel(MPTTModel):
    parent = TreeForeignKey(
        "self", null=True, blank=True, related_name="children", on_delete=models.CASCADE
    )
    now = models.DateTimeField(auto_now_add=True)

    class MPTTMeta:
        order_insertion_by = ("now",)


# test registering of remote model
class Group(models.Model):
    name = models.CharField(max_length=100)


TreeForeignKey(
    Group, blank=True, null=True, on_delete=models.CASCADE
).contribute_to_class(Group, "parent")
mptt.register(Group, order_insertion_by=("name",))


class Book(MPTTModel):
    parent = TreeForeignKey(
        "self", null=True, blank=True, related_name="children", on_delete=models.CASCADE
    )

    name = models.CharField(max_length=50)
    fk = TreeForeignKey(
        Category,
        null=True,
        blank=True,
        related_name="books_fk",
        on_delete=models.CASCADE,
    )
    m2m = TreeManyToManyField(Category, blank=True, related_name="books_m2m")


class UniqueTogetherModel(MPTTModel):
    class Meta:
        unique_together = (
            (
                "parent",
                "code",
            ),
        )

    parent = TreeForeignKey("self", null=True, on_delete=models.CASCADE)
    code = models.CharField(max_length=10)


class NullableOrderedInsertionModel(MPTTModel):
    name = models.CharField(max_length=50, null=True)
    parent = TreeForeignKey(
        "self", null=True, blank=True, related_name="children", on_delete=models.CASCADE
    )

    class MPTTMeta:
        order_insertion_by = ["name"]

    def __str__(self):
        return self.name


class NullableDescOrderedInsertionModel(MPTTModel):
    name = models.CharField(max_length=50, null=True)
    parent = TreeForeignKey(
        "self", null=True, blank=True, related_name="children", on_delete=models.CASCADE
    )

    class MPTTMeta:
        order_insertion_by = ["-name"]

    def __str__(self):
        return self.name


class FakeNotConcreteField(Field):
    """Returning None as column results in the field being not concrete"""

    def get_attname_column(self):
        return self.name, None


class NotConcreteFieldModel(MPTTModel):
    parent = TreeForeignKey(
        "self", null=True, blank=True, related_name="children", on_delete=models.CASCADE
    )
    not_concrete_field = FakeNotConcreteField()