import os
import json


def record_data_lineage(path_to_output_file, projectPath, metadata):
    
    path_to_output_dir, output_file = os.path.split(path_to_output_file)
         
    path_to_metadata_file = '/'.join([path_to_output_dir,'data_lineage_metadata.json'])
    # Ensure the file exists
    if not os.path.exists(path_to_metadata_file):
        with open(path_to_metadata_file, 'w') as f:
            json.dump({}, f)  # Initialize empty JSON

    # Read the existing JSON
    with open(path_to_metadata_file, 'r') as metadata_file:
        try:
            json_dict = json.load(metadata_file)
        except json.JSONDecodeError:
            json_dict = {}  # Start fresh if file is invalid

    # Compute relative output file path and update the JSON object
    #grelpath_to_output_file = os.path.relpath(path_to_output_file, start=projectPath).replace(os.sep, '/')
    json_dict[output_file] = metadata

    # Write updated JSON back to the file
    with open(path_to_metadata_file, 'w') as metadata_file:
        json.dump(json_dict, metadata_file, indent=4)
        
    
    print(f"Metadata for calibrated data saved to {path_to_metadata_file}")
    
    return 0

def get_metadata(path_to_file):

    path, filename = os.path.split(path_to_file)

    path_to_metadata = None
    for item in os.listdir(path):
        if 'metadata.json' in item:
            path_to_metadata = os.path.normpath(os.path.join(path,item))
    metadata = {}
    if path_to_file:
        with open(path_to_metadata,'r') as stream:
            metadata = json.load(stream)
    
        metadata = metadata.get(filename,{})

    return metadata