"""
Tests for the image generation application.

This module contains unit tests for the various components of the application.
"""

import unittest
from unittest.mock import MagicMock, patch
import os
from pathlib import Path

import numpy as np
from PIL import Image

# Import application modules
from config import MODEL_REPO_ID, MAX_SEED
from model import ModelManager
from utils import save_image, format_generation_info, GenerationHistory


class TestConfig(unittest.TestCase):
    """Test the configuration module."""
    
    def test_config_values(self):
        """Test that configuration values are properly set."""
        from config import (
            MODEL_REPO_ID, 
            DEFAULT_GUIDANCE_SCALE,
            DEFAULT_INFERENCE_STEPS,
            DEFAULT_WIDTH,
            DEFAULT_HEIGHT,
            MAX_IMAGE_SIZE,
            EXAMPLE_PROMPTS
        )
        
        self.assertEqual(MODEL_REPO_ID, "stabilityai/sdxl-turbo")
        self.assertEqual(DEFAULT_GUIDANCE_SCALE, 0.0)
        self.assertEqual(DEFAULT_INFERENCE_STEPS, 2)
        self.assertEqual(DEFAULT_WIDTH, 1024)
        self.assertEqual(DEFAULT_HEIGHT, 1024)
        self.assertEqual(MAX_IMAGE_SIZE, 1024)
        self.assertIsInstance(EXAMPLE_PROMPTS, list)
        self.assertTrue(len(EXAMPLE_PROMPTS) > 0)


class TestModelManager(unittest.TestCase):
    """Test the ModelManager class."""
    
    @patch('model.DiffusionPipeline')
    def test_init(self, mock_pipeline):
        """Test ModelManager initialization."""
        manager = ModelManager()
        self.assertIn(manager.device, ["cuda", "cpu"])
        self.assertIsNone(manager.pipe)
    
    @patch('model.DiffusionPipeline.from_pretrained')
    def test_load_model(self, mock_from_pretrained):
        """Test model loading."""
        # Setup mock
        mock_pipe = MagicMock()
        mock_from_pretrained.return_value = mock_pipe
        mock_pipe.to.return_value = mock_pipe
        
        # Test loading
        manager = ModelManager()
        manager.load_model()
        
        # Verify calls
        mock_from_pretrained.assert_called_once_with(
            MODEL_REPO_ID, 
            torch_dtype=manager.torch_dtype
        )
        mock_pipe.to.assert_called_once_with(manager.device)
        self.assertEqual(manager.pipe, mock_pipe)
    
    @patch('model.DiffusionPipeline')
    def test_generate_image_with_randomize(self, mock_pipeline):
        """Test image generation with randomized seed."""
        # Setup mock
        manager = ModelManager()
        manager.pipe = MagicMock()
        mock_image = MagicMock()
        manager.pipe.return_value = MagicMock(images=[mock_image])
        
        # Test generation with randomized seed
        prompt = "test prompt"
        image, seed = manager.generate_image(
            prompt=prompt,
            randomize_seed=True
        )
        
        # Verify result
        self.assertEqual(image, mock_image)
        self.assertGreaterEqual(seed, 0)
        self.assertLessEqual(seed, MAX_SEED)


class TestUtils(unittest.TestCase):
    """Test utility functions."""
    
    def setUp(self):
        """Set up test environment."""
        # Create a test image
        self.test_image = Image.new('RGB', (100, 100), color='red')
        
        # Ensure test output directory exists
        from utils import OUTPUTS_DIR
        self.test_outputs_dir = OUTPUTS_DIR
        self.test_outputs_dir.mkdir(exist_ok=True)
    
    def test_save_image(self):
        """Test image saving functionality."""
        prompt = "test image prompt"
        filepath = save_image(self.test_image, prompt)
        
        # Check that file was created
        self.assertTrue(os.path.exists(filepath))
        self.assertTrue(filepath.endswith(".png"))
        
        # Clean up
        os.remove(filepath)
    
    def test_format_generation_info(self):
        """Test generation info formatting."""
        prompt = "test prompt"
        negative_prompt = "test negative"
        seed = 42
        width = 512
        height = 512
        guidance_scale = 7.5
        steps = 30
        
        info = format_generation_info(
            prompt, negative_prompt, seed, width, height, guidance_scale, steps
        )
        
        # Check that all parameters are included in the info string
        self.assertIn(prompt, info)
        self.assertIn(negative_prompt, info)
        self.assertIn(str(seed), info)
        self.assertIn(str(width), info)
        self.assertIn(str(height), info)
        self.assertIn(str(guidance_scale), info)
        self.assertIn(str(steps), info)
    
    def test_generation_history(self):
        """Test the GenerationHistory class."""
        history = GenerationHistory(max_history=3)
        
        # Test empty history
        self.assertEqual(len(history.history), 0)
        self.assertEqual(history.get_latest(), [])
        
        # Add entries
        for i in range(5):
            history.add(
                self.test_image,
                f"prompt {i}",
                f"negative {i}",
                i,
                512,
                512,
                7.5,
                30
            )
        
        # Check that history is limited to max_history
        self.assertEqual(len(history.history), 3)
        
        # Check that entries are in correct order (newest last)
        latest = history.get_latest(1)[0]
        self.assertEqual(latest["prompt"], "prompt 4")
        
        # Test clear
        history.clear()
        self.assertEqual(len(history.history), 0)


if __name__ == '__main__':
    unittest.main()