import uuid
from django.db import models
from django.utils.text import slugify
from django.conf import settings
from apps.profiles.models import Institution


class EventCategory(models.TextChoices):
    RELIGIOUS = 'religious', 'Religious'
    EDUCATIONAL = 'educational', 'Educational'
    CULTURAL = 'cultural', 'Cultural'
    COUNSELING = 'counseling', 'Counseling'
    CONFERENCE = 'conference', 'Conference'
    WORKSHOP = 'workshop', 'Workshop'


class LocationType(models.TextChoices):
    IN_PERSON = 'in_person', 'In Person'
    ONLINE = 'online', 'Online'
    HYBRID = 'hybrid', 'Hybrid'


class RegistrationStatus(models.TextChoices):
    REGISTERED = 'registered', 'Registered'
    ATTENDED = 'attended', 'Attended'
    CANCELLED = 'cancelled', 'Cancelled'


class Event(models.Model):
    LANGUAGE_CHOICES = [
        ('fa', 'Persian'),
        ('ar', 'Arabic'),
        ('en', 'English'),
        ('ur', 'Urdu'),
        ('fr', 'French'),
    ]

    title = models.CharField(max_length=255, verbose_name="Event Title")
    slug = models.SlugField(max_length=280, unique=True, blank=True, verbose_name="Slug")
    description = models.TextField(verbose_name="Event Description")
    organizer = models.ForeignKey(
        Institution,
        on_delete=models.CASCADE,
        related_name='events',
        verbose_name="Organizer Institution"
    )
    created_by = models.ForeignKey(
        settings.AUTH_USER_MODEL,
        on_delete=models.SET_NULL,
        null=True,
        blank=True,
        related_name='created_events',
        verbose_name="Created By"
    )
    category = models.CharField(
        max_length=30,
        choices=EventCategory.choices,
        default=EventCategory.CULTURAL,
        verbose_name="Category"
    )
    event_date = models.DateField(verbose_name="Event Date")
    start_time = models.TimeField(verbose_name="Start Time")
    end_time = models.TimeField(null=True, blank=True, verbose_name="End Time")
    
    speaker_name = models.CharField(max_length=255, blank=True, verbose_name="Speaker Name")
    speaker_title = models.CharField(max_length=255, blank=True, verbose_name="Speaker Title / Affiliation")
    speaker_avatar = models.ImageField(upload_to='events/speakers/', blank=True, null=True, verbose_name="Speaker Avatar")
    
    location_type = models.CharField(
        max_length=20,
        choices=LocationType.choices,
        default=LocationType.IN_PERSON,
        verbose_name="Location Type"
    )
    venue_address = models.CharField(max_length=500, blank=True, verbose_name="Venue Address")
    online_meeting_url = models.URLField(blank=True, verbose_name="Online Meeting Link")
    cover_image = models.ImageField(upload_to='events/covers/', blank=True, null=True, verbose_name="Cover Image")
    
    capacity = models.PositiveIntegerField(default=100, verbose_name="Capacity Limit")
    registration_count = models.PositiveIntegerField(default=0, verbose_name="Current Registrations")
    
    is_active = models.BooleanField(default=True, verbose_name="Is Active")
    is_featured = models.BooleanField(default=False, verbose_name="Is Featured")
    tags = models.JSONField(default=list, blank=True, verbose_name="Tags")
    language = models.CharField(max_length=10, choices=LANGUAGE_CHOICES, default='fa', verbose_name="Language")
    
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        ordering = ['event_date', 'start_time']
        verbose_name = "Event"
        verbose_name_plural = "Events"
        indexes = [
            models.Index(fields=['event_date', 'is_active']),
            models.Index(fields=['category', 'is_active']),
            models.Index(fields=['organizer', 'is_active']),
        ]

    def __str__(self):
        return f"{self.title} ({self.event_date})"

    def save(self, *args, **kwargs):
        if not self.slug:
            base_slug = slugify(self.title, allow_unicode=True) or "event"
            unique_slug = base_slug
            counter = 1
            while Event.objects.filter(slug=unique_slug).exclude(pk=self.pk).exists():
                unique_slug = f"{base_slug}-{counter}"
                counter += 1
            self.slug = unique_slug
        super().save(*args, **kwargs)

    def update_registration_count(self):
        count = self.registrations.filter(status=RegistrationStatus.REGISTERED).count()
        if self.registration_count != count:
            self.registration_count = count
            self.save(update_fields=['registration_count', 'updated_at'])


class EventRegistration(models.Model):
    event = models.ForeignKey(
        Event,
        on_delete=models.CASCADE,
        related_name='registrations',
        verbose_name="Event"
    )
    user = models.ForeignKey(
        settings.AUTH_USER_MODEL,
        on_delete=models.CASCADE,
        related_name='event_registrations',
        verbose_name="Participant"
    )
    status = models.CharField(
        max_length=20,
        choices=RegistrationStatus.choices,
        default=RegistrationStatus.REGISTERED,
        verbose_name="Status"
    )
    notes = models.TextField(blank=True, verbose_name="Participant Notes")
    registered_at = models.DateTimeField(auto_now_add=True)

    class Meta:
        unique_together = ('event', 'user')
        ordering = ['-registered_at']
        verbose_name = "Event Registration"
        verbose_name_plural = "Event Registrations"

    def __str__(self):
        return f"{self.user} -> {self.event.title} ({self.status})"