from django.db import models
from django.urls import reverse
from django.utils.text import slugify
from django.contrib.contenttypes.fields import GenericRelation
from django.core.exceptions import ValidationError
from decimal import Decimal, ROUND_DOWN, InvalidOperation
from typing import Tuple, Optional, Any, TYPE_CHECKING

from companies.models import Company
from history_tracking.signals import get_current_branch
from media.models import Photo
from history_tracking.models import HistoricalModel
from location.models import Location

if TYPE_CHECKING:
    from rides.models import Ride


class Park(HistoricalModel):
    id: int  # Type hint for Django's automatic id field
    STATUS_CHOICES = [
        ("OPERATING", "Operating"),
        ("CLOSED_TEMP", "Temporarily Closed"),
        ("CLOSED_PERM", "Permanently Closed"),
        ("UNDER_CONSTRUCTION", "Under Construction"),
        ("DEMOLISHED", "Demolished"),
        ("RELOCATED", "Relocated"),
    ]

    name = models.CharField(max_length=255)
    slug = models.SlugField(max_length=255, unique=True)
    description = models.TextField(blank=True)
    status = models.CharField(
        max_length=20, choices=STATUS_CHOICES, default="OPERATING"
    )

    # Location fields using GenericRelation
    location = GenericRelation(Location, related_query_name='park')

    # Details
    opening_date = models.DateField(null=True, blank=True)
    closing_date = models.DateField(null=True, blank=True)
    operating_season = models.CharField(max_length=255, blank=True)
    size_acres = models.DecimalField(
        max_digits=10, decimal_places=2, null=True, blank=True
    )
    website = models.URLField(blank=True)

    # Statistics
    average_rating = models.DecimalField(
        max_digits=3, decimal_places=2, null=True, blank=True
    )
    ride_count = models.IntegerField(null=True, blank=True)
    coaster_count = models.IntegerField(null=True, blank=True)

    # Relationships
    owner = models.ForeignKey(
        Company, on_delete=models.SET_NULL, null=True, blank=True, related_name="parks"
    )
    photos = GenericRelation(Photo, related_query_name="park")
    areas: models.Manager['ParkArea']  # Type hint for reverse relation
    rides: models.Manager['Ride']  # Type hint for reverse relation from rides app

    # Metadata
    created_at = models.DateTimeField(auto_now_add=True, null=True)
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        ordering = ["name"]

    def __str__(self) -> str:
        return self.name

    def save(self, *args: Any, **kwargs: Any) -> None:
        if not self.slug:
            self.slug = slugify(self.name)
            
        # Get the branch from context or use default
        from history_tracking.signals import get_current_branch
        current_branch = get_current_branch()
        
        if current_branch:
            # Save in the context of the current branch
            super().save(*args, **kwargs)
        else:
            # If no branch context, save in main branch
            from history_tracking.models import VersionBranch
            main_branch, _ = VersionBranch.objects.get_or_create(
                name='main',
                defaults={'metadata': {'type': 'default_branch'}}
            )
            
            from history_tracking.signals import ChangesetContextManager
            with ChangesetContextManager(branch=main_branch):
                super().save(*args, **kwargs)

    def get_version_info(self) -> dict:
        """Get version control information for this park"""
        from history_tracking.models import VersionBranch, ChangeSet
        from django.contrib.contenttypes.models import ContentType
        
        content_type = ContentType.objects.get_for_model(self)
        latest_changes = ChangeSet.objects.filter(
            content_type=content_type,
            object_id=self.pk,
            status='applied'
        ).order_by('-created_at')[:5]
        
        active_branches = VersionBranch.objects.filter(
            changesets__content_type=content_type,
            changesets__object_id=self.pk,
            is_active=True
        ).distinct()
        
        return {
            'latest_changes': latest_changes,
            'active_branches': active_branches,
            'current_branch': get_current_branch(),
            'total_changes': latest_changes.count()
        }

    def get_absolute_url(self) -> str:
        return reverse("parks:park_detail", kwargs={"slug": self.slug})

    @property
    def formatted_location(self) -> str:
        if self.location.exists():
            location = self.location.first()
            if location:
                return location.get_formatted_address()
        return ""

    @property
    def coordinates(self) -> Optional[Tuple[float, float]]:
        """Returns coordinates as a tuple (latitude, longitude)"""
        if self.location.exists():
            location = self.location.first()
            if location:
                return location.coordinates
        return None

    @classmethod
    def get_by_slug(cls, slug: str) -> Tuple['Park', bool]:
        """Get park by current or historical slug"""
        try:
            return cls.objects.get(slug=slug), False
        except cls.DoesNotExist:
            # Check historical slugs
            history = cls.history.filter(slug=slug).order_by("-history_date").first()  # type: ignore[attr-defined]
            if history:
                try:
                    return cls.objects.get(pk=history.instance.pk), True
                except cls.DoesNotExist as e:
                    raise cls.DoesNotExist("No park found with this slug") from e
            raise cls.DoesNotExist("No park found with this slug")


class ParkArea(HistoricalModel):
    id: int  # Type hint for Django's automatic id field
    park = models.ForeignKey(Park, on_delete=models.CASCADE, related_name="areas")
    name = models.CharField(max_length=255)
    slug = models.SlugField(max_length=255)
    description = models.TextField(blank=True)
    opening_date = models.DateField(null=True, blank=True)
    closing_date = models.DateField(null=True, blank=True)

    # Metadata
    created_at = models.DateTimeField(auto_now_add=True, null=True)
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        ordering = ["name"]
        unique_together = ["park", "slug"]

    def __str__(self) -> str:
        return f"{self.name} at {self.park.name}"

    def save(self, *args: Any, **kwargs: Any) -> None:
        if not self.slug:
            self.slug = slugify(self.name)
            
        # Get the branch from context or use default
        from history_tracking.signals import get_current_branch
        current_branch = get_current_branch()
        
        if current_branch:
            # Save in the context of the current branch
            super().save(*args, **kwargs)
        else:
            # If no branch context, save in main branch
            from history_tracking.models import VersionBranch
            main_branch, _ = VersionBranch.objects.get_or_create(
                name='main',
                defaults={'metadata': {'type': 'default_branch'}}
            )
            
            from history_tracking.signals import ChangesetContextManager
            with ChangesetContextManager(branch=main_branch):
                super().save(*args, **kwargs)

    def get_version_info(self) -> dict:
        """Get version control information for this park area"""
        from history_tracking.models import VersionBranch, ChangeSet
        from django.contrib.contenttypes.models import ContentType
        
        content_type = ContentType.objects.get_for_model(self)
        latest_changes = ChangeSet.objects.filter(
            content_type=content_type,
            object_id=self.pk,
            status='applied'
        ).order_by('-created_at')[:5]
        
        active_branches = VersionBranch.objects.filter(
            changesets__content_type=content_type,
            changesets__object_id=self.pk,
            is_active=True
        ).distinct()
        
        return {
            'latest_changes': latest_changes,
            'active_branches': active_branches,
            'current_branch': get_current_branch(),
            'total_changes': latest_changes.count(),
            'parent_park_branch': self.park.get_version_info()['current_branch']
        }

    def get_absolute_url(self) -> str:
        return reverse(
            "parks:area_detail",
            kwargs={"park_slug": self.park.slug, "area_slug": self.slug},
        )

    @classmethod
    def get_by_slug(cls, slug: str) -> Tuple['ParkArea', bool]:
        """Get area by current or historical slug"""
        try:
            return cls.objects.get(slug=slug), False
        except cls.DoesNotExist:
            # Check historical slugs
            history = cls.history.filter(slug=slug).order_by("-history_date").first()  # type: ignore[attr-defined]
            if history:
                try:
                    return cls.objects.get(pk=history.instance.pk), True
                except cls.DoesNotExist as e:
                    raise cls.DoesNotExist("No park area found with this slug") from e
            raise cls.DoesNotExist("No park area found with this slug")