import argparse
import sys
import json
from pathlib import Path

# Add the utils directory to the Python path
utils_path = Path(__file__).parent / 'utils'
sys.path.append(str(utils_path))

from file_utils import find_files_by_extension
from deep_parser import parse_scene_or_prefab

def main():
    """
    Main function to run the low-level data extraction process.
    """
    parser = argparse.ArgumentParser(
        description="Generates a deeply detailed, per-GameObject breakdown of scenes and prefabs."
    )
    parser.add_argument(
        "--input",
        type=str,
        required=True,
        help="The root directory of the target Unity project."
    )
    parser.add_argument(
        "--output",
        type=str,
        required=True,
        help="The directory where the generated output folder will be saved."
    )
    args = parser.parse_args()

    input_dir = Path(args.input).resolve()
    output_dir = Path(args.output).resolve()

    if not input_dir.is_dir():
        print(f"Error: Input path '{input_dir}' is not a valid directory.", file=sys.stderr)
        sys.exit(1)

    # Create the main output folder, named "LowLevel"
    low_level_output_dir = output_dir / "LowLevel"
    try:
        low_level_output_dir.mkdir(parents=True, exist_ok=True)
        print(f"Output will be saved to: {low_level_output_dir}")
    except OSError as e:
        print(f"Error: Could not create output directory '{low_level_output_dir}'. {e}", file=sys.stderr)
        sys.exit(1)

    # --- Orchestration ---
    assets_dir = input_dir / "Assets"
    if not assets_dir.is_dir():
        print(f"Error: 'Assets' directory not found in '{input_dir}'.", file=sys.stderr)
        return

    scene_files = find_files_by_extension(str(assets_dir), '.unity')
    prefab_files = find_files_by_extension(str(assets_dir), '.prefab')
    files_to_process = scene_files + prefab_files
    
    print(f"\nFound {len(files_to_process)} scene/prefab files to process.")

    for file_path_str in files_to_process:
        file_path = Path(file_path_str)
        print(f"\nProcessing: {file_path.name}")

        gameobject_list = parse_scene_or_prefab(str(file_path))

        if gameobject_list:
            # Create the output subdirectory for this asset
            relative_path = file_path.relative_to(input_dir)
            asset_output_dir = low_level_output_dir / relative_path
            try:
                asset_output_dir.mkdir(parents=True, exist_ok=True)
            except OSError as e:
                print(f"Error creating directory {asset_output_dir}: {e}", file=sys.stderr)
                continue

            print(f"Saving {len(gameobject_list)} GameObjects to {asset_output_dir}")
            for go_data in gameobject_list:
                file_id = go_data.get('fileID')
                if file_id:
                    output_json_path = asset_output_dir / f"{file_id}.json"
                    try:
                        with open(output_json_path, 'w', encoding='utf-8') as f:
                            json.dump(go_data, f, separators=(',', ':'))
                    except IOError as e:
                        print(f"Error writing to {output_json_path}: {e}", file=sys.stderr)
        else:
            print(f"Skipped {file_path.name} as deep parsing failed.")

    print("\nLow-level extraction complete.")

if __name__ == "__main__":
    main()