from rest_framework.permissions import BasePermission
from django.core.exceptions import ValidationError

from users.models import User

MAX_IMAGE_SIZE_MB = 2
MAX_VIDEO_SIZE_MB = 50

def validate_score(score):
    if score < 1 or score > 5:
        raise ValidationError('Score must be between 1 and 5')

def validate_image_size(file):
    max_size = MAX_IMAGE_SIZE_MB * 1024 * 1024
    if file.size > max_size:
        raise ValidationError(f'Max size file is {MAX_IMAGE_SIZE_MB} MB')
    
def validate_video_size(file):
    max_size = MAX_VIDEO_SIZE_MB * 1024 * 1024
    if file.size > max_size:
        raise ValidationError(f'Max size file is {MAX_VIDEO_SIZE_MB} MB')
    
class IsProfessorOnly(BasePermission):
    def has_permission(self, request, view):
        user: User = request.user
        return user.is_authenticated and (user.role == User.Roles.PROFESSOR.value or user.is_superuser)