import json

def split_json(input_file, output_prefix, num_chunks):
    # Open the large JSON file
    with open(input_file, 'r') as file:
        data = json.load(file)
    
    # Get the list of keys (to split them into chunks)
    keys = list(data.keys())
    
    # Calculate the chunk size (roughly equal parts)
    total_keys = len(keys)
    chunk_size = total_keys // num_chunks
    remainder = total_keys % num_chunks

    # Split the data into chunks and save each chunk to a separate file
    start = 0
    for i in range(num_chunks):
        # Determine the end index for each chunk
        end = start + chunk_size + (1 if i < remainder else 0)
        
        # Create the chunked dictionary
        chunk_keys = keys[start:end]
        chunk_data = {key: data[key] for key in chunk_keys}
        
        # Generate a file name for the chunk
        output_file = f"{output_prefix}_{i + 1}.json"
        
        # Write the chunk data to a new JSON file
        with open(output_file, 'w') as chunk_file:
            json.dump(chunk_data, chunk_file, indent=4)
        
        print(f"Saved chunk {i + 1} to {output_file}")
        
        start = end

# Example usage
split_json('full_gavl_polygons_obj.json', 'smaller_jsons/output_chunk', 20)