from django import forms
from decimal import Decimal, InvalidOperation, ROUND_DOWN
from autocomplete import AutocompleteWidget

from django import forms
from .models import Park
from .models.location import ParkLocation
from .querysets import get_base_park_queryset


class ParkAutocomplete(forms.Form):
    """Autocomplete for searching parks.
    
    Features:
    - Name-based search with partial matching
    - Prefetches related owner data
    - Applies standard park queryset filtering
    - Includes park status and location in results
    """
    model = Park
    search_attrs = ['name']  # We'll match on park names
    
    def get_search_results(self, search):
        """Return search results with related data."""
        return (get_base_park_queryset()
                .filter(name__icontains=search)
                .select_related('operator', 'property_owner')
                .order_by('name'))
    
    def format_result(self, park):
        """Format each park result with status and location."""
        location = park.formatted_location
        location_text = f" • {location}" if location else ""
        return {
            'key': str(park.pk),
            'label': park.name,
            'extra': f"{park.get_status_display()}{location_text}"
        }


class ParkSearchForm(forms.Form):
    """Form for searching parks with autocomplete."""
    park = forms.ModelChoiceField(
        queryset=Park.objects.all(),
        required=False,
        widget=AutocompleteWidget(
            ac_class=ParkAutocomplete,
            attrs={'class': 'w-full border-gray-300 rounded-lg form-input dark:border-gray-600 dark:bg-gray-700 dark:text-white',
                   'placeholder': 'Search parks...'}
        )
    )


class ParkForm(forms.ModelForm):
    """Form for creating and updating Park objects with location support"""
    # Location fields
    latitude = forms.DecimalField(
        max_digits=9,
        decimal_places=6,
        required=False,
        widget=forms.HiddenInput()
    )
    longitude = forms.DecimalField(
        max_digits=10,
        decimal_places=6,
        required=False,
        widget=forms.HiddenInput()
    )
    street_address = forms.CharField(
        max_length=255,
        required=False,
        widget=forms.TextInput(
            attrs={
                "class": "w-full border-gray-300 rounded-lg form-input dark:border-gray-600 dark:bg-gray-700 dark:text-white"
            }
        )
    )
    city = forms.CharField(
        max_length=255,
        required=False,
        widget=forms.TextInput(
            attrs={
                "class": "w-full border-gray-300 rounded-lg form-input dark:border-gray-600 dark:bg-gray-700 dark:text-white"
            }
        )
    )
    state = forms.CharField(
        max_length=255,
        required=False,
        widget=forms.TextInput(
            attrs={
                "class": "w-full border-gray-300 rounded-lg form-input dark:border-gray-600 dark:bg-gray-700 dark:text-white"
            }
        )
    )
    country = forms.CharField(
        max_length=255,
        required=False,
        widget=forms.TextInput(
            attrs={
                "class": "w-full border-gray-300 rounded-lg form-input dark:border-gray-600 dark:bg-gray-700 dark:text-white"
            }
        )
    )
    postal_code = forms.CharField(
        max_length=20,
        required=False,
        widget=forms.TextInput(
            attrs={
                "class": "w-full border-gray-300 rounded-lg form-input dark:border-gray-600 dark:bg-gray-700 dark:text-white"
            }
        )
    )

    class Meta:
        model = Park
        fields = [
            "name",
            "description",
            "operator",
            "property_owner",
            "status",
            "opening_date",
            "closing_date",
            "operating_season",
            "size_acres",
            "website",
            # Location fields handled separately
            "latitude",
            "longitude",
            "street_address",
            "city",
            "state",
            "country",
            "postal_code",
        ]
        widgets = {
            "name": forms.TextInput(
                attrs={
                    "class": "w-full border-gray-300 rounded-lg form-input dark:border-gray-600 dark:bg-gray-700 dark:text-white"
                }
            ),
            "description": forms.Textarea(
                attrs={
                    "class": "w-full border-gray-300 rounded-lg form-textarea dark:border-gray-600 dark:bg-gray-700 dark:text-white",
                    "rows": 2,
                }
            ),
            "operator": forms.Select(
                attrs={
                    "class": "w-full border-gray-300 rounded-lg form-select dark:border-gray-600 dark:bg-gray-700 dark:text-white"
                }
            ),
            "property_owner": forms.Select(
                attrs={
                    "class": "w-full border-gray-300 rounded-lg form-select dark:border-gray-600 dark:bg-gray-700 dark:text-white"
                }
            ),
            "status": forms.Select(
                attrs={
                    "class": "w-full border-gray-300 rounded-lg form-select dark:border-gray-600 dark:bg-gray-700 dark:text-white"
                }
            ),
            "opening_date": forms.DateInput(
                attrs={
                    "type": "date",
                    "class": "w-full border-gray-300 rounded-lg form-input dark:border-gray-600 dark:bg-gray-700 dark:text-white",
                }
            ),
            "closing_date": forms.DateInput(
                attrs={
                    "type": "date",
                    "class": "w-full border-gray-300 rounded-lg form-input dark:border-gray-600 dark:bg-gray-700 dark:text-white",
                }
            ),
            "operating_season": forms.TextInput(
                attrs={
                    "class": "w-full border-gray-300 rounded-lg form-input dark:border-gray-600 dark:bg-gray-700 dark:text-white",
                    "placeholder": "e.g., Year-round, Summer only, etc.",
                }
            ),
            "size_acres": forms.NumberInput(
                attrs={
                    "class": "w-full border-gray-300 rounded-lg form-input dark:border-gray-600 dark:bg-gray-700 dark:text-white",
                    "step": "0.01",
                    "min": "0",
                }
            ),
            "website": forms.URLInput(
                attrs={
                    "class": "w-full border-gray-300 rounded-lg form-input dark:border-gray-600 dark:bg-gray-700 dark:text-white",
                    "placeholder": "https://example.com",
                }
            ),
        }

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        # Pre-fill location fields if editing existing park
        if self.instance and self.instance.pk and self.instance.location.exists():
            location = self.instance.location.first()
            self.fields['latitude'].initial = location.latitude
            self.fields['longitude'].initial = location.longitude
            self.fields['street_address'].initial = location.street_address
            self.fields['city'].initial = location.city
            self.fields['state'].initial = location.state
            self.fields['country'].initial = location.country
            self.fields['postal_code'].initial = location.postal_code

    def clean_latitude(self):
        latitude = self.cleaned_data.get('latitude')
        if latitude is not None:
            try:
                # Convert to Decimal for precise handling
                latitude = Decimal(str(latitude))
                # Round to exactly 6 decimal places
                latitude = latitude.quantize(Decimal('0.000001'), rounding=ROUND_DOWN)
                
                # Validate range
                if latitude < -90 or latitude > 90:
                    raise forms.ValidationError("Latitude must be between -90 and 90 degrees.")
                
                # Convert to string to preserve exact decimal places
                return str(latitude)
            except (InvalidOperation, TypeError) as e:
                raise forms.ValidationError("Invalid latitude value.") from e
        return latitude

    def clean_longitude(self):
        longitude = self.cleaned_data.get('longitude')
        if longitude is not None:
            try:
                # Convert to Decimal for precise handling
                longitude = Decimal(str(longitude))
                # Round to exactly 6 decimal places
                longitude = longitude.quantize(Decimal('0.000001'), rounding=ROUND_DOWN)
                
                # Validate range
                if longitude < -180 or longitude > 180:
                    raise forms.ValidationError("Longitude must be between -180 and 180 degrees.")
                
                # Convert to string to preserve exact decimal places
                return str(longitude)
            except (InvalidOperation, TypeError) as e:
                raise forms.ValidationError("Invalid longitude value.") from e
        return longitude

    def save(self, commit=True):
        park = super().save(commit=False)
        
        # Prepare location data
        location_data = {
            'name': park.name,
            'location_type': 'park',
            'latitude': self.cleaned_data.get('latitude'),
            'longitude': self.cleaned_data.get('longitude'),
            'street_address': self.cleaned_data.get('street_address'),
            'city': self.cleaned_data.get('city'),
            'state': self.cleaned_data.get('state'),
            'country': self.cleaned_data.get('country'),
            'postal_code': self.cleaned_data.get('postal_code'),
        }
        
        # Handle location: update if exists, create if not
        try:
            park_location = park.location
            # Update existing location
            for key, value in location_data.items():
                if key in ['latitude', 'longitude'] and value:
                    continue  # Handle coordinates separately
                if hasattr(park_location, key):
                    setattr(park_location, key, value)
            
            # Handle coordinates if provided
            if 'latitude' in location_data and 'longitude' in location_data:
                if location_data['latitude'] and location_data['longitude']:
                    park_location.set_coordinates(
                        float(location_data['latitude']),
                        float(location_data['longitude'])
                    )
            park_location.save()
        except ParkLocation.DoesNotExist:
            # Create new ParkLocation
            coordinates_data = {}
            if 'latitude' in location_data and 'longitude' in location_data:
                if location_data['latitude'] and location_data['longitude']:
                    coordinates_data = {
                        'latitude': float(location_data['latitude']),
                        'longitude': float(location_data['longitude'])
                    }
            
            # Remove coordinate fields from location_data for creation
            creation_data = {k: v for k, v in location_data.items()
                           if k not in ['latitude', 'longitude']}
            creation_data.setdefault('country', 'USA')
            
            park_location = ParkLocation.objects.create(
                park=park,
                **creation_data
            )
            
            if coordinates_data:
                park_location.set_coordinates(
                    coordinates_data['latitude'],
                    coordinates_data['longitude']
                )
                park_location.save()
        
        if commit:
            park.save()
        
        return park