import uuid
from pathlib import Path
from django.conf import settings
from django.db import models
from apps.core.models import PublicIdModel
def attachment_path(instance,filename):
    ext=Path(filename).suffix.lower(); t=instance.message.ticket; m=instance.message
    return f"tickets/{t.created_at:%Y/%m}/{t.public_id}/{m.public_id}/{uuid.uuid4().hex}{ext}"
class AttachmentPolicy(models.Model):
    attachment_type=models.CharField(max_length=20,unique=True); is_enabled=models.BooleanField(default=True); max_file_size=models.PositiveBigIntegerField(); max_files_per_message=models.PositiveSmallIntegerField(default=10); allowed_extensions=models.JSONField(default=list); allowed_mime_types=models.JSONField(default=list); sort_order=models.PositiveIntegerField(default=0); updated_at=models.DateTimeField(auto_now=True)
class Attachment(PublicIdModel,models.Model):
    class Type(models.TextChoices): IMAGE="IMAGE","تصویر"; VIDEO="VIDEO","ویدئو"; VOICE="VOICE","صدا"; PDF="PDF","PDF"; WORD="WORD","Word"; EXCEL="EXCEL","Excel"; ZIP="ZIP","ZIP"; RAR="RAR","RAR"; OTHER="OTHER","سایر"
    message=models.ForeignKey("messaging.Message",on_delete=models.PROTECT,related_name="attachments"); file=models.FileField(upload_to=attachment_path,max_length=500); original_name=models.CharField(max_length=255); stored_name=models.CharField(max_length=255); relative_path=models.CharField(max_length=500); attachment_type=models.CharField(max_length=20,choices=Type.choices); mime_type=models.CharField(max_length=150); extension=models.CharField(max_length=20); file_size=models.PositiveBigIntegerField(); uploaded_by=models.ForeignKey(settings.AUTH_USER_MODEL,on_delete=models.PROTECT); created_at=models.DateTimeField(auto_now_add=True)
    class Meta: permissions=[("download_attachment","Can download attachment"),("manage_attachment_policy","Can manage attachment policy")]