"""
Batch processing functionality for RAGAnything

Contains methods for processing multiple files in batches
"""

import asyncio
from typing import Optional, List
from pathlib import Path


class BatchMixin:
    """BatchMixin class containing batch processing functionality for RAGAnything"""

    async def process_folder_complete(
        self,
        folder_path: str,
        output_dir: str = None,
        parse_method: str = None,
        display_stats: bool = None,
        split_by_character: str | None = None,
        split_by_character_only: bool = False,
        file_extensions: Optional[List[str]] = None,
        recursive: bool = None,
        max_workers: int = None,
    ):
        """
        Process all files in a folder in batch

        Args:
            folder_path: Path to the folder to process
            output_dir: MinerU output directory (defaults to config.mineru_output_dir)
            parse_method: Parse method (defaults to config.mineru_parse_method)
            display_stats: Whether to display content statistics for each file (defaults to False for batch processing)
            split_by_character: Optional character to split text by
            split_by_character_only: If True, split only by the specified character
            file_extensions: List of file extensions to process (defaults to config.supported_file_extensions)
            recursive: Whether to recursively process subfolders (defaults to config.recursive_folder_processing)
            max_workers: Maximum number of concurrent workers (defaults to config.max_concurrent_files)
        """
        # Ensure LightRAG is initialized
        await self._ensure_lightrag_initialized()

        # Use config defaults if not provided
        if output_dir is None:
            output_dir = self.config.mineru_output_dir
        if parse_method is None:
            parse_method = self.config.mineru_parse_method
        if display_stats is None:
            display_stats = False  # Default to False for batch processing
        if recursive is None:
            recursive = self.config.recursive_folder_processing
        if max_workers is None:
            max_workers = self.config.max_concurrent_files
        if file_extensions is None:
            file_extensions = self.config.supported_file_extensions

        folder_path = Path(folder_path)
        if not folder_path.exists() or not folder_path.is_dir():
            raise ValueError(
                f"Folder does not exist or is not a valid directory: {folder_path}"
            )

        # Convert file extensions to set for faster lookup
        target_extensions = set(ext.lower().strip() for ext in file_extensions)

        # Log the extensions being used
        self.logger.info(
            f"Processing files with extensions: {sorted(target_extensions)}"
        )

        # Collect all files to process
        files_to_process = []

        if recursive:
            # Recursively traverse all subfolders
            for file_path in folder_path.rglob("*"):
                if (
                    file_path.is_file()
                    and file_path.suffix.lower() in target_extensions
                ):
                    files_to_process.append(file_path)
        else:
            # Process only current folder
            for file_path in folder_path.glob("*"):
                if (
                    file_path.is_file()
                    and file_path.suffix.lower() in target_extensions
                ):
                    files_to_process.append(file_path)

        if not files_to_process:
            self.logger.info(f"No files to process found in {folder_path}")
            return

        self.logger.info(f"Found {len(files_to_process)} files to process")
        self.logger.info("File type distribution:")

        # Count file types
        file_type_count = {}
        for file_path in files_to_process:
            ext = file_path.suffix.lower()
            file_type_count[ext] = file_type_count.get(ext, 0) + 1

        for ext, count in sorted(file_type_count.items()):
            self.logger.info(f"  {ext}: {count} files")

        # Create progress tracking
        processed_count = 0
        failed_files = []

        # Use semaphore to control concurrency
        semaphore = asyncio.Semaphore(max_workers)

        async def process_single_file(file_path: Path, index: int) -> None:
            """Process a single file"""
            async with semaphore:
                nonlocal processed_count
                try:
                    self.logger.info(
                        f"[{index}/{len(files_to_process)}] Processing: {file_path}"
                    )

                    # Create separate output directory for each file
                    file_output_dir = Path(output_dir) / file_path.stem
                    file_output_dir.mkdir(parents=True, exist_ok=True)

                    # Process file
                    await self.process_document_complete(
                        file_path=str(file_path),
                        output_dir=str(file_output_dir),
                        parse_method=parse_method,
                        display_stats=display_stats,
                        split_by_character=split_by_character,
                        split_by_character_only=split_by_character_only,
                    )

                    processed_count += 1
                    self.logger.info(
                        f"[{index}/{len(files_to_process)}] Successfully processed: {file_path}"
                    )

                except Exception as e:
                    self.logger.error(
                        f"[{index}/{len(files_to_process)}] Failed to process: {file_path}"
                    )
                    self.logger.error(f"Error: {str(e)}")
                    failed_files.append((file_path, str(e)))

        # Create all processing tasks
        tasks = []
        for index, file_path in enumerate(files_to_process, 1):
            task = process_single_file(file_path, index)
            tasks.append(task)

        # Wait for all tasks to complete
        await asyncio.gather(*tasks, return_exceptions=True)

        # Output processing statistics
        self.logger.info("\n===== Batch Processing Complete =====")
        self.logger.info(f"Total files: {len(files_to_process)}")
        self.logger.info(f"Successfully processed: {processed_count}")
        self.logger.info(f"Failed: {len(failed_files)}")

        if failed_files:
            self.logger.info("\nFailed files:")
            for file_path, error in failed_files:
                self.logger.info(f"  - {file_path}: {error}")

        return {
            "total": len(files_to_process),
            "success": processed_count,
            "failed": len(failed_files),
            "failed_files": failed_files,
        }