from django.db import models
from django.utils.translation import gettext_lazy as _

# 1. Define choices globally so they can be reused
class StatusColorChoices(models.TextChoices):
    RED = 'red', _('Red')
    GREEN = 'green', _('Green')
    BLUE = 'blue', _('Blue')
    YELLOW = 'yellow', _('Yellow')
    ORANGE = 'orange', _('Orange')
    PURPLE = 'purple', _('Purple')
    GRAY = 'gray', _('Gray')

# 2. Create the Abstract Mixin
class ColorPaletteMixin(models.Model):
    """
    An abstract base class that provides color choice fields 
    and hex code properties to any model that inherits it.
    """
    COLOR_PALETTE = {
        'red':    '#D33A3A',
        'green':  '#1DAC43',
        'blue':   '#5172E1',
        'yellow': '#EDC130',
        'orange': '#E67E22',
        'purple': '#7C5CC4',
        'gray':   '#374151',
    }

    color = models.CharField(
        max_length=20, 
        choices=StatusColorChoices.choices, 
        verbose_name=_('color'),
        default=StatusColorChoices.GRAY
    )

    class Meta:
        abstract = True

    @property
    def main_color_code(self):
        return self.COLOR_PALETTE.get(self.color, '#000000')


from django.utils.text import slugify
from django.http import HttpResponsePermanentRedirect
from django.urls import reverse


class LowercaseSlugMixin(models.Model):
    """
    Mixin to automatically generate a lowercase, unicode-supporting unique slug
    from a source field (default: 'title') on save.
    """
    slug_source_field = 'title'

    class Meta:
        abstract = True

    def save(self, *args, **kwargs):
        # 1. Generate slug if empty
        if not self.slug:
            source_value = getattr(self, self.slug_source_field, '') or ''
            base_slug = slugify(source_value, allow_unicode=True) or 'slug'
            base_slug = base_slug.lower()
            
            # Ensure uniqueness
            slug = base_slug
            counter = 1
            model_class = self.__class__
            
            # Exclude current instance from conflict check if it exists in database
            queryset = model_class.objects.all()
            if self.pk:
                queryset = queryset.exclude(pk=self.pk)
                
            while queryset.filter(slug=slug).exists():
                slug = f"{base_slug}-{counter}"
                counter += 1
                
            self.slug = slug
        else:
            # 2. Force existing slug to lowercase (handling both string and JSONField lists)
            if isinstance(self.slug, str):
                self.slug = self.slug.lower()
            elif isinstance(self.slug, list):
                for item in self.slug:
                    if isinstance(item, dict) and "title" in item and item["title"]:
                        item["title"] = str(item["title"]).lower()

        super().save(*args, **kwargs)


class CanonicalSlugViewSetMixin:
    """
    Mixin for DRF Views/ViewSets to enforce lowercase slugs and redirect with 301.
    """
    def dispatch(self, request, *args, **kwargs):
        if request.method == 'GET':
            slug = kwargs.get('slug')
            if slug and any(char.isupper() for char in slug):
                resolved = request.resolver_match
                new_kwargs = {**resolved.kwargs, 'slug': slug.lower()}
                
                # Reconstruct path using reverse
                new_path = reverse(resolved.view_name, args=resolved.args, kwargs=new_kwargs)
                
                # Ensure trailing slash
                if not new_path.endswith('/'):
                    new_path += '/'
                
                # Append query parameters if any
                query_string = request.META.get('QUERY_STRING')
                if query_string:
                    new_path = f"{new_path}?{query_string}"
                
                return HttpResponsePermanentRedirect(new_path)
                
        return super().dispatch(request, *args, **kwargs)


from utils.exceptions import ResourceGone


class Gone410ViewMixin:
    """
    Mixin for DRF detail Views/ViewSets to return 410 Gone instead of 404
    for inactive/soft-deleted records.
    """
    active_field_name = 'status'
    active_expected_value = True

    def get_object(self):
        obj = super().get_object()
        active_val = getattr(obj, self.active_field_name, None)
        if active_val != self.active_expected_value:
            raise ResourceGone()
        return obj