"""
CompI Phase 2.E: Style Reference/Example Image to AI Art Generation

This module implements multimodal AI art generation that combines:
- Text prompts with style and mood conditioning
- Reference image style transfer and guidance
- Image-to-image generation with controllable strength
- Support for both local files and web URLs
- Advanced style analysis and prompt enhancement

Features:
- Support for various image formats and web sources
- Real-time image analysis and style suggestion
- Controllable reference strength for creative flexibility
- Comprehensive metadata logging and filename conventions
- Batch processing capabilities with multiple variations
"""

import os
import sys
import torch
import json
from datetime import datetime
from typing import Dict, List, Optional, Tuple, Union
from pathlib import Path
import logging

# Add project root to path
sys.path.append(os.path.join(os.path.dirname(__file__), '..', '..'))

from diffusers import StableDiffusionImg2ImgPipeline, StableDiffusionPipeline
from PIL import Image
import numpy as np

from src.utils.image_utils import ImageProcessor, StyleAnalyzer
from src.utils.logging_utils import setup_logger
from src.utils.file_utils import ensure_directory_exists, generate_filename
from src.config import (
    STABLE_DIFFUSION_IMG2IMG_MODEL, 
    OUTPUTS_DIR, 
    DEFAULT_IMAGE_SIZE,
    DEFAULT_INFERENCE_STEPS,
    DEFAULT_GUIDANCE_SCALE
)

# Setup logging
logger = setup_logger(__name__)

class CompIPhase2ERefImageToImage:
    """
    CompI Phase 2.E: Style Reference/Example Image to AI Art Generation System
    
    Combines text prompts with reference image style guidance for enhanced creativity
    """
    
    def __init__(
        self,
        model_name: str = STABLE_DIFFUSION_IMG2IMG_MODEL,
        device: Optional[str] = None,
        enable_attention_slicing: bool = True,
        enable_memory_efficient_attention: bool = True
    ):
        """
        Initialize the CompI Phase 2.E system
        
        Args:
            model_name: Hugging Face model identifier
            device: Device to run on ('cuda', 'cpu', or None for auto)
            enable_attention_slicing: Enable attention slicing for memory efficiency
            enable_memory_efficient_attention: Enable memory efficient attention
        """
        self.model_name = model_name
        self.device = device or ("cuda" if torch.cuda.is_available() else "cpu")
        
        # Initialize components
        self.image_processor = ImageProcessor()
        self.style_analyzer = StyleAnalyzer()
        
        # Initialize pipelines (lazy loading)
        self._img2img_pipeline = None
        self._txt2img_pipeline = None
        
        # Configuration
        self.enable_attention_slicing = enable_attention_slicing
        self.enable_memory_efficient_attention = enable_memory_efficient_attention
        
        logger.info(f"Initialized CompI Phase 2.E on device: {self.device}")
        
    @property
    def img2img_pipeline(self) -> StableDiffusionImg2ImgPipeline:
        """Lazy load img2img pipeline"""
        if self._img2img_pipeline is None:
            logger.info(f"Loading img2img pipeline: {self.model_name}")
            self._img2img_pipeline = StableDiffusionImg2ImgPipeline.from_pretrained(
                self.model_name,
                torch_dtype=torch.float16 if self.device == "cuda" else torch.float32,
                safety_checker=None,  # Disabled for creative use
                requires_safety_checker=False
            )
            self._img2img_pipeline = self._img2img_pipeline.to(self.device)
            
            if self.enable_attention_slicing:
                self._img2img_pipeline.enable_attention_slicing()
            if self.enable_memory_efficient_attention and hasattr(self._img2img_pipeline, 'enable_memory_efficient_attention'):
                self._img2img_pipeline.enable_memory_efficient_attention()
                
        return self._img2img_pipeline
        
    @property
    def txt2img_pipeline(self) -> StableDiffusionPipeline:
        """Lazy load txt2img pipeline for fallback"""
        if self._txt2img_pipeline is None:
            logger.info(f"Loading txt2img pipeline: {self.model_name}")
            self._txt2img_pipeline = StableDiffusionPipeline.from_pretrained(
                self.model_name,
                torch_dtype=torch.float16 if self.device == "cuda" else torch.float32,
                safety_checker=None,  # Disabled for creative use
                requires_safety_checker=False
            )
            self._txt2img_pipeline = self._txt2img_pipeline.to(self.device)
            
            if self.enable_attention_slicing:
                self._txt2img_pipeline.enable_attention_slicing()
            if self.enable_memory_efficient_attention and hasattr(self._txt2img_pipeline, 'enable_memory_efficient_attention'):
                self._txt2img_pipeline.enable_memory_efficient_attention()
                
        return self._txt2img_pipeline
        
    def load_reference_image(
        self, 
        source: Union[str, Path, Image.Image],
        preprocess: bool = True
    ) -> Optional[Tuple[Image.Image, Dict]]:
        """
        Load and analyze reference image from various sources
        
        Args:
            source: Image source (file path, URL, or PIL Image)
            preprocess: Whether to preprocess the image
            
        Returns:
            Tuple of (processed_image, analysis_results) or None if failed
        """
        try:
            # Load image based on source type
            if isinstance(source, Image.Image):
                image = source.convert('RGB')
                source_info = "PIL Image object"
            elif isinstance(source, (str, Path)):
                source_str = str(source)
                if source_str.startswith(('http://', 'https://')):
                    image = self.image_processor.load_image_from_url(source_str)
                    source_info = f"URL: {source_str}"
                else:
                    image = self.image_processor.load_image_from_file(source_str)
                    source_info = f"File: {source_str}"
                    
                if image is None:
                    return None
            else:
                logger.error(f"Unsupported source type: {type(source)}")
                return None
                
            # Preprocess if requested
            if preprocess:
                image = self.image_processor.preprocess_image(image, DEFAULT_IMAGE_SIZE)
                
            # Analyze image properties
            properties = self.image_processor.analyze_image_properties(image)
            style_suggestions = self.style_analyzer.suggest_style_keywords(properties)
            image_hash = self.image_processor.generate_image_hash(image)
            
            analysis = {
                'source': source_info,
                'properties': properties,
                'style_suggestions': style_suggestions,
                'hash': image_hash,
                'processed_size': image.size
            }
            
            logger.info(f"Successfully loaded and analyzed reference image: {analysis}")
            return image, analysis
            
        except Exception as e:
            logger.error(f"Error loading reference image: {e}")
            return None
            
    def enhance_prompt_with_style(
        self, 
        base_prompt: str,
        style: str = "",
        mood: str = "",
        style_suggestions: List[str] = None
    ) -> str:
        """
        Enhance prompt with style information from reference image
        
        Args:
            base_prompt: Base text prompt
            style: Additional style keywords
            mood: Mood/atmosphere keywords
            style_suggestions: Suggested keywords from image analysis
            
        Returns:
            Enhanced prompt string
        """
        try:
            prompt_parts = [base_prompt.strip()]
            
            # Add explicit style
            if style.strip():
                prompt_parts.append(style.strip())
                
            # Add mood
            if mood.strip():
                prompt_parts.append(mood.strip())
                
            # Add style suggestions from image analysis
            if style_suggestions:
                # Limit to top 3 suggestions to avoid prompt bloat
                top_suggestions = style_suggestions[:3]
                prompt_parts.extend(top_suggestions)
                
            enhanced_prompt = ", ".join(prompt_parts)
            logger.info(f"Enhanced prompt: {enhanced_prompt}")
            return enhanced_prompt
            
        except Exception as e:
            logger.error(f"Error enhancing prompt: {e}")
            return base_prompt

    def generate_with_reference(
        self,
        prompt: str,
        reference_image: Image.Image,
        style: str = "",
        mood: str = "",
        strength: float = 0.5,
        num_images: int = 1,
        num_inference_steps: int = DEFAULT_INFERENCE_STEPS,
        guidance_scale: float = DEFAULT_GUIDANCE_SCALE,
        seed: Optional[int] = None,
        style_suggestions: List[str] = None
    ) -> List[Dict]:
        """
        Generate images using reference image guidance

        Args:
            prompt: Text prompt
            reference_image: Reference PIL Image
            style: Style keywords
            mood: Mood keywords
            strength: Reference strength (0.0-1.0, higher = closer to reference)
            num_images: Number of images to generate
            num_inference_steps: Number of denoising steps
            guidance_scale: Classifier-free guidance scale
            seed: Random seed for reproducibility
            style_suggestions: Style suggestions from image analysis

        Returns:
            List of generation results with metadata
        """
        try:
            # Enhance prompt with style information
            enhanced_prompt = self.enhance_prompt_with_style(
                prompt, style, mood, style_suggestions
            )

            results = []

            for i in range(num_images):
                # Set up random seed
                if seed is not None:
                    current_seed = seed + i
                else:
                    current_seed = torch.seed()

                generator = torch.Generator(device=self.device).manual_seed(current_seed)

                # Generate image
                logger.info(f"Generating image {i+1}/{num_images} with reference guidance")

                with torch.autocast(self.device) if self.device == "cuda" else torch.no_grad():
                    result = self.img2img_pipeline(
                        prompt=enhanced_prompt,
                        image=reference_image,
                        strength=strength,
                        num_inference_steps=num_inference_steps,
                        guidance_scale=guidance_scale,
                        generator=generator
                    )

                generated_image = result.images[0]

                # Create metadata
                metadata = {
                    'prompt': prompt,
                    'enhanced_prompt': enhanced_prompt,
                    'style': style,
                    'mood': mood,
                    'strength': strength,
                    'num_inference_steps': num_inference_steps,
                    'guidance_scale': guidance_scale,
                    'seed': current_seed,
                    'model': self.model_name,
                    'generation_type': 'img2img_reference',
                    'timestamp': datetime.now().isoformat(),
                    'device': self.device,
                    'reference_size': reference_image.size,
                    'output_size': generated_image.size,
                    'style_suggestions': style_suggestions or []
                }

                results.append({
                    'image': generated_image,
                    'metadata': metadata,
                    'index': i
                })

            logger.info(f"Successfully generated {len(results)} images with reference guidance")
            return results

        except Exception as e:
            logger.error(f"Error generating images with reference: {e}")
            return []

    def generate_without_reference(
        self,
        prompt: str,
        style: str = "",
        mood: str = "",
        num_images: int = 1,
        num_inference_steps: int = DEFAULT_INFERENCE_STEPS,
        guidance_scale: float = DEFAULT_GUIDANCE_SCALE,
        seed: Optional[int] = None
    ) -> List[Dict]:
        """
        Generate images without reference (fallback to text-to-image)

        Args:
            prompt: Text prompt
            style: Style keywords
            mood: Mood keywords
            num_images: Number of images to generate
            num_inference_steps: Number of denoising steps
            guidance_scale: Classifier-free guidance scale
            seed: Random seed for reproducibility

        Returns:
            List of generation results with metadata
        """
        try:
            # Enhance prompt
            enhanced_prompt = self.enhance_prompt_with_style(prompt, style, mood)

            results = []

            for i in range(num_images):
                # Set up random seed
                if seed is not None:
                    current_seed = seed + i
                else:
                    current_seed = torch.seed()

                generator = torch.Generator(device=self.device).manual_seed(current_seed)

                # Generate image
                logger.info(f"Generating image {i+1}/{num_images} without reference")

                with torch.autocast(self.device) if self.device == "cuda" else torch.no_grad():
                    result = self.txt2img_pipeline(
                        prompt=enhanced_prompt,
                        height=DEFAULT_IMAGE_SIZE[1],
                        width=DEFAULT_IMAGE_SIZE[0],
                        num_inference_steps=num_inference_steps,
                        guidance_scale=guidance_scale,
                        generator=generator
                    )

                generated_image = result.images[0]

                # Create metadata
                metadata = {
                    'prompt': prompt,
                    'enhanced_prompt': enhanced_prompt,
                    'style': style,
                    'mood': mood,
                    'num_inference_steps': num_inference_steps,
                    'guidance_scale': guidance_scale,
                    'seed': current_seed,
                    'model': self.model_name,
                    'generation_type': 'txt2img_fallback',
                    'timestamp': datetime.now().isoformat(),
                    'device': self.device,
                    'output_size': generated_image.size
                }

                results.append({
                    'image': generated_image,
                    'metadata': metadata,
                    'index': i
                })

            logger.info(f"Successfully generated {len(results)} images without reference")
            return results

        except Exception as e:
            logger.error(f"Error generating images without reference: {e}")
            return []

    def save_results(
        self,
        results: List[Dict],
        output_dir: Path = OUTPUTS_DIR,
        reference_info: Optional[Dict] = None
    ) -> List[str]:
        """
        Save generation results with comprehensive metadata

        Args:
            results: List of generation results
            output_dir: Output directory
            reference_info: Reference image information

        Returns:
            List of saved file paths
        """
        try:
            ensure_directory_exists(output_dir)
            saved_files = []

            for result in results:
                image = result['image']
                metadata = result['metadata']
                index = result['index']

                # Generate filename
                timestamp = datetime.now().strftime("%Y%m%d_%H%M%S")
                prompt_slug = "_".join(metadata['prompt'].lower().split()[:5])
                style_slug = metadata.get('style', '').replace(' ', '')[:10]
                mood_slug = metadata.get('mood', '').replace(' ', '')[:10]

                # Add reference indicator
                ref_indicator = "REFIMG" if metadata['generation_type'] == 'img2img_reference' else "NOREFIMG"

                filename = f"{prompt_slug}_{style_slug}_{mood_slug}_{timestamp}_seed{metadata['seed']}_{ref_indicator}_v{index+1}.png"
                filepath = output_dir / filename

                # Save image
                image.save(filepath)

                # Add reference info to metadata if available
                if reference_info:
                    metadata['reference_info'] = reference_info

                # Save metadata
                metadata_filename = filepath.stem + "_metadata.json"
                metadata_filepath = output_dir / metadata_filename

                with open(metadata_filepath, 'w') as f:
                    json.dump(metadata, f, indent=2, default=str)

                saved_files.extend([str(filepath), str(metadata_filepath)])
                logger.info(f"Saved: {filepath}")

            return saved_files

        except Exception as e:
            logger.error(f"Error saving results: {e}")
            return []

    def generate_batch(
        self,
        prompt: str,
        reference_source: Optional[Union[str, Path, Image.Image]] = None,
        style: str = "",
        mood: str = "",
        strength: float = 0.5,
        num_images: int = 1,
        num_inference_steps: int = DEFAULT_INFERENCE_STEPS,
        guidance_scale: float = DEFAULT_GUIDANCE_SCALE,
        seed: Optional[int] = None,
        save_results: bool = True,
        output_dir: Path = OUTPUTS_DIR
    ) -> Dict:
        """
        Complete batch generation pipeline

        Args:
            prompt: Text prompt
            reference_source: Reference image source (file, URL, or PIL Image)
            style: Style keywords
            mood: Mood keywords
            strength: Reference strength (only used if reference provided)
            num_images: Number of images to generate
            num_inference_steps: Number of denoising steps
            guidance_scale: Classifier-free guidance scale
            seed: Random seed for reproducibility
            save_results: Whether to save results to disk
            output_dir: Output directory for saved files

        Returns:
            Dictionary with results and metadata
        """
        try:
            logger.info(f"Starting batch generation: {num_images} images")

            reference_image = None
            reference_info = None
            style_suggestions = []

            # Load and analyze reference image if provided
            if reference_source is not None:
                ref_result = self.load_reference_image(reference_source)
                if ref_result:
                    reference_image, reference_info = ref_result
                    style_suggestions = reference_info.get('style_suggestions', [])
                    logger.info(f"Using reference image with suggestions: {style_suggestions}")
                else:
                    logger.warning("Failed to load reference image, falling back to text-only generation")

            # Generate images
            if reference_image is not None:
                results = self.generate_with_reference(
                    prompt=prompt,
                    reference_image=reference_image,
                    style=style,
                    mood=mood,
                    strength=strength,
                    num_images=num_images,
                    num_inference_steps=num_inference_steps,
                    guidance_scale=guidance_scale,
                    seed=seed,
                    style_suggestions=style_suggestions
                )
            else:
                results = self.generate_without_reference(
                    prompt=prompt,
                    style=style,
                    mood=mood,
                    num_images=num_images,
                    num_inference_steps=num_inference_steps,
                    guidance_scale=guidance_scale,
                    seed=seed
                )

            # Save results if requested
            saved_files = []
            if save_results and results:
                saved_files = self.save_results(results, output_dir, reference_info)

            # Compile final results
            batch_result = {
                'results': results,
                'reference_info': reference_info,
                'saved_files': saved_files,
                'generation_summary': {
                    'total_images': len(results),
                    'prompt': prompt,
                    'style': style,
                    'mood': mood,
                    'has_reference': reference_image is not None,
                    'style_suggestions': style_suggestions,
                    'timestamp': datetime.now().isoformat()
                }
            }

            logger.info(f"Batch generation complete: {len(results)} images generated")
            return batch_result

        except Exception as e:
            logger.error(f"Error in batch generation: {e}")
            return {
                'results': [],
                'reference_info': None,
                'saved_files': [],
                'error': str(e)
            }