"""
Dataset Manager for NanoBanana Image Generator
Handles saving generated images to Hugging Face Dataset Repository
"""

import os
import json
import logging
from typing import Optional, Dict, Any, List
from datetime import datetime
from pathlib import Path
from PIL import Image
from io import BytesIO
import tempfile

from huggingface_hub import HfApi, upload_file, upload_folder, create_repo, list_repo_files

logger = logging.getLogger(__name__)


class DatasetManager:
    """
    Manages image uploads to Hugging Face Dataset Repository
    with custom folder structure support
    """

    def __init__(self, repo_id: str, token: str):
        """
        Initialize Dataset Manager

        Args:
            repo_id: Hugging Face dataset repository ID (e.g., "username/dataset-name")
            token: Hugging Face API token with write access
        """
        self.repo_id = repo_id
        self.token = token
        self.api = HfApi(token=token)

        # Ensure repository exists
        self._ensure_repo_exists()

        logger.info(f"DatasetManager initialized for repository: {repo_id}")

    def _ensure_repo_exists(self):
        """Create dataset repository if it doesn't exist"""
        try:
            # Try to get repository info
            self.api.repo_info(repo_id=self.repo_id, repo_type="dataset")
            logger.info(f"Dataset repository {self.repo_id} already exists")
        except Exception as e:
            # Repository doesn't exist, create it
            try:
                self.api.create_repo(
                    repo_id=self.repo_id,
                    repo_type="dataset",
                    private=False,
                    exist_ok=True
                )
                logger.info(f"Created new dataset repository: {self.repo_id}")

                # Create initial README
                readme_content = f"""# NanoBanana Generated Images Dataset

This dataset contains images generated by the NanoBanana Gemini Image Generator.

## Structure
- `images/` - Generated images organized by date or custom folders
  - `YYYY_MM_DD/` - Images generated on specific dates
  - Custom folders as specified during generation

## Metadata
Each image is accompanied by a JSON metadata file containing:
- Generation prompt
- Model used
- Generation parameters
- Timestamp

## Usage
You can load this dataset using the Hugging Face `datasets` library:

```python
from datasets import load_dataset
dataset = load_dataset("{self.repo_id}")
```

---
Generated with 🍌 NanoBanana Image Generator
"""
                self._upload_readme(readme_content)
            except Exception as create_error:
                logger.warning(f"Could not create repository: {create_error}")

    def _upload_readme(self, content: str):
        """Upload README.md to repository"""
        try:
            with tempfile.NamedTemporaryFile(mode='w', suffix='.md', delete=False) as f:
                f.write(content)
                temp_path = f.name

            self.api.upload_file(
                path_or_fileobj=temp_path,
                path_in_repo="README.md",
                repo_id=self.repo_id,
                repo_type="dataset"
            )

            # Clean up temp file
            os.unlink(temp_path)
        except Exception as e:
            logger.error(f"Failed to upload README: {e}")

    def save_image(
        self,
        image: Image.Image,
        prompt: str,
        folder_name: Optional[str] = None,
        filename: Optional[str] = None,  # 新しいパラメータ追加
        metadata: Optional[Dict[str, Any]] = None
    ) -> Optional[str]:
        """
        Save image to dataset repository

        Args:
            image: PIL Image object to save
            prompt: Generation prompt used
            folder_name: Optional folder name. If None, uses YYYY_MM_DD format
            filename: Optional custom filename (without extension). If None, auto-generates
            metadata: Optional additional metadata to save

        Returns:
            URL to the uploaded image in the dataset repository, or None if failed
        """
        try:
            # Determine folder name
            if not folder_name:
                folder_name = datetime.now().strftime("%Y_%m_%d")

            # Generate or use custom filename
            if filename:
                # Sanitize filename - remove extension if provided
                clean_filename = os.path.splitext(filename)[0]
                # Replace invalid characters
                clean_filename = "".join(c if c.isalnum() or c in '-_' else '_' for c in clean_filename)
                # Ensure filename is not empty
                if not clean_filename:
                    clean_filename = f"image_{datetime.now().strftime('%Y%m%d_%H%M%S_%f')[:-3]}"
                image_filename = f"{clean_filename}.png"
                metadata_filename = f"{clean_filename}.json"
            else:
                # Auto-generate filename
                timestamp = datetime.now().strftime("%Y%m%d_%H%M%S_%f")[:-3]  # Milliseconds
                image_filename = f"image_{timestamp}.png"
                metadata_filename = f"image_{timestamp}.json"

            # Paths in repository
            image_path_in_repo = f"images/{folder_name}/{image_filename}"
            metadata_path_in_repo = f"images/{folder_name}/{metadata_filename}"

            # Create metadata
            image_metadata = {
                "prompt": prompt,
                "timestamp": datetime.now().isoformat(),
                "folder": folder_name,
                "filename": image_filename,
                "custom_filename": filename is not None,  # Track if filename was custom
                "size": {
                    "width": image.width,
                    "height": image.height
                }
            }

            # Add additional metadata if provided
            if metadata:
                image_metadata.update(metadata)

            # Save image to temporary file
            with tempfile.NamedTemporaryFile(suffix='.png', delete=False) as img_temp:
                image.save(img_temp, format='PNG')
                img_temp_path = img_temp.name

            # Save metadata to temporary file
            with tempfile.NamedTemporaryFile(mode='w', suffix='.json', delete=False) as meta_temp:
                json.dump(image_metadata, meta_temp, indent=2)
                meta_temp_path = meta_temp.name

            # Upload image
            self.api.upload_file(
                path_or_fileobj=img_temp_path,
                path_in_repo=image_path_in_repo,
                repo_id=self.repo_id,
                repo_type="dataset",
                commit_message=f"Add generated image: {image_filename}"
            )

            # Upload metadata
            self.api.upload_file(
                path_or_fileobj=meta_temp_path,
                path_in_repo=metadata_path_in_repo,
                repo_id=self.repo_id,
                repo_type="dataset",
                commit_message=f"Add metadata for: {image_filename}"
            )

            # Clean up temp files
            os.unlink(img_temp_path)
            os.unlink(meta_temp_path)

            # Return URL to the image
            dataset_url = f"https://huggingface.co/datasets/{self.repo_id}/blob/main/{image_path_in_repo}"

            logger.info(f"Successfully saved image to dataset: {image_path_in_repo}")
            return dataset_url

        except Exception as e:
            logger.error(f"Failed to save image to dataset: {e}")
            return None

    def get_folders(self) -> List[str]:
        """
        Get list of folders in the dataset repository

        Returns:
            List of folder names
        """
        try:
            files = self.api.list_repo_files(
                repo_id=self.repo_id,
                repo_type="dataset"
            )

            # Extract folder names from paths
            folders = set()
            for file in files:
                if file.startswith("images/"):
                    parts = file.split("/")
                    if len(parts) > 1:
                        folder = parts[1]
                        folders.add(folder)

            return sorted(list(folders))

        except Exception as e:
            logger.error(f"Failed to get folders: {e}")
            return []

    def get_images_in_folder(self, folder_name: str) -> List[Dict[str, str]]:
        """
        Get list of images in a specific folder

        Args:
            folder_name: Name of the folder

        Returns:
            List of dictionaries containing image info
        """
        try:
            files = self.api.list_repo_files(
                repo_id=self.repo_id,
                repo_type="dataset"
            )

            images = []
            folder_prefix = f"images/{folder_name}/"

            for file in files:
                if file.startswith(folder_prefix) and file.endswith(".png"):
                    # Get corresponding metadata file
                    metadata_file = file.replace(".png", ".json")

                    image_info = {
                        "filename": os.path.basename(file),
                        "path": file,
                        "url": f"https://huggingface.co/datasets/{self.repo_id}/resolve/main/{file}",
                        "metadata_url": f"https://huggingface.co/datasets/{self.repo_id}/resolve/main/{metadata_file}"
                    }
                    images.append(image_info)

            return sorted(images, key=lambda x: x["filename"], reverse=True)

        except Exception as e:
            logger.error(f"Failed to get images in folder {folder_name}: {e}")
            return []

    def batch_save_images(
        self,
        images_data: List[Dict[str, Any]],
        folder_name: Optional[str] = None
    ) -> List[Optional[str]]:
        """
        Save multiple images in batch

        Args:
            images_data: List of dicts with 'image', 'prompt', and optional 'metadata'
            folder_name: Optional folder name for all images

        Returns:
            List of URLs for uploaded images
        """
        urls = []
        for data in images_data:
            url = self.save_image(
                image=data['image'],
                prompt=data['prompt'],
                folder_name=folder_name,
                metadata=data.get('metadata')
            )
            urls.append(url)

        return urls