from django.test import TestCase, override_settings
from django.core.files.uploadedfile import SimpleUploadedFile
from django.contrib.auth import get_user_model
from django.contrib.contenttypes.models import ContentType
from django.utils import timezone
from datetime import datetime
from PIL import Image, ExifTags
import io
from .models import Photo
from parks.models import Park

User = get_user_model()

class PhotoModelTests(TestCase):
    def setUp(self):
        # Create a test user
        self.user = User.objects.create_user(
            username='testuser',
            password='testpass123'
        )
        
        # Create a test park for photo association
        self.park = Park.objects.create(
            name='Test Park',
            slug='test-park'
        )
        
        self.content_type = ContentType.objects.get_for_model(Park)

    def create_test_image_with_exif(self, date_taken=None):
        """Helper method to create a test image with EXIF data"""
        # Create a test image
        image = Image.new('RGB', (100, 100), color='red')
        image_io = io.BytesIO()
        
        # Add EXIF data if date_taken is provided
        if date_taken:
            exif_dict = {
                "0th": {},
                "Exif": {
                    ExifTags.Base.DateTimeOriginal: date_taken.strftime("%Y:%m:%d %H:%M:%S").encode()
                }
            }
            image.save(image_io, 'JPEG', exif=exif_dict)
        else:
            image.save(image_io, 'JPEG')
        
        image_io.seek(0)
        return SimpleUploadedFile(
            'test.jpg',
            image_io.getvalue(),
            content_type='image/jpeg'
        )

    def test_photo_creation(self):
        """Test basic photo creation"""
        photo = Photo.objects.create(
            image=SimpleUploadedFile(
                'test.jpg',
                b'dummy image data',
                content_type='image/jpeg'
            ),
            caption='Test Caption',
            uploaded_by=self.user,
            content_type=self.content_type,
            object_id=self.park.pk
        )
        
        self.assertEqual(photo.caption, 'Test Caption')
        self.assertEqual(photo.uploaded_by, self.user)
        self.assertIsNone(photo.date_taken)

    def test_exif_date_extraction(self):
        """Test EXIF date extraction from uploaded photos"""
        test_date = datetime(2024, 1, 1, 12, 0, 0)
        image_file = self.create_test_image_with_exif(test_date)
        
        photo = Photo.objects.create(
            image=image_file,
            uploaded_by=self.user,
            content_type=self.content_type,
            object_id=self.park.pk
        )
        
        if photo.date_taken:
            self.assertEqual(
                photo.date_taken.strftime("%Y-%m-%d %H:%M:%S"),
                test_date.strftime("%Y-%m-%d %H:%M:%S")
            )
        else:
            self.skipTest("EXIF data extraction not supported in test environment")

    def test_photo_without_exif(self):
        """Test photo upload without EXIF data"""
        image_file = self.create_test_image_with_exif()  # No date provided
        
        photo = Photo.objects.create(
            image=image_file,
            uploaded_by=self.user,
            content_type=self.content_type,
            object_id=self.park.pk
        )
        
        self.assertIsNone(photo.date_taken)

    def test_default_caption(self):
        """Test default caption generation"""
        photo = Photo.objects.create(
            image=SimpleUploadedFile(
                'test.jpg',
                b'dummy image data',
                content_type='image/jpeg'
            ),
            uploaded_by=self.user,
            content_type=self.content_type,
            object_id=self.park.pk
        )
        
        expected_prefix = f"Uploaded by {self.user.username} on"
        self.assertTrue(photo.caption.startswith(expected_prefix))

    def test_primary_photo_toggle(self):
        """Test primary photo functionality"""
        # Create two photos
        photo1 = Photo.objects.create(
            image=SimpleUploadedFile(
                'test1.jpg',
                b'dummy image data',
                content_type='image/jpeg'
            ),
            uploaded_by=self.user,
            content_type=self.content_type,
            object_id=self.park.pk,
            is_primary=True
        )
        
        photo2 = Photo.objects.create(
            image=SimpleUploadedFile(
                'test2.jpg',
                b'dummy image data',
                content_type='image/jpeg'
            ),
            uploaded_by=self.user,
            content_type=self.content_type,
            object_id=self.park.pk,
            is_primary=True
        )
        
        # Refresh from database
        photo1.refresh_from_db()
        photo2.refresh_from_db()
        
        # Verify only photo2 is primary
        self.assertFalse(photo1.is_primary)
        self.assertTrue(photo2.is_primary)

    @override_settings(MEDIA_ROOT='test_media/')
    def test_photo_upload_path(self):
        """Test photo upload path generation"""
        photo = Photo.objects.create(
            image=SimpleUploadedFile(
                'test.jpg',
                b'dummy image data',
                content_type='image/jpeg'
            ),
            uploaded_by=self.user,
            content_type=self.content_type,
            object_id=self.park.pk
        )
        
        expected_path = f"park/{self.park.slug}/"
        self.assertTrue(photo.image.name.startswith(expected_path))

    def test_date_taken_field(self):
        """Test date_taken field functionality"""
        test_date = timezone.now()
        photo = Photo.objects.create(
            image=SimpleUploadedFile(
                'test.jpg',
                b'dummy image data',
                content_type='image/jpeg'
            ),
            uploaded_by=self.user,
            content_type=self.content_type,
            object_id=self.park.pk,
            date_taken=test_date
        )
        
        self.assertEqual(photo.date_taken, test_date)