import mysql


def generate_new_s3_key(old_key, prefix):
    """
    Generates a new S3 key by prepending the destination prefix to the old key,
    thereby preserving the original path structure.
    """
    if not isinstance(old_key, str) or not old_key:
        return None
    
    # Ensure the prefix ends with a slash if it's not empty and doesn't already end with one.
    prefixed_path = prefix
    if prefix and not prefix.endswith('/'):
        prefixed_path += '/'
        
    # Combine the prefix and the old key. If the old key starts with a slash, strip it.
    final_key = old_key.lstrip('/')
    
    return f"{prefixed_path}{final_key}"

def move_s3_object(s3_client, source_bucket, source_key, dest_bucket, dest_key):
    """
    Performs the S3 'move' operation (Copy + Delete).
    
    Returns True on success, False otherwise.
    """
    copy_source = {
        'Bucket': source_bucket,
        'Key': source_key
    }

    try:
        print(f"  -> Copying '{source_key}' to '{dest_key}' in '{dest_bucket}'...")
        # 1. Copy the object
        s3_client.copy_object(
            CopySource=copy_source,
            Bucket=dest_bucket,
            Key=dest_key
        )
        print("  -> Copy object successful.")
        
        # print(f"  -> Deleting original object from '{source_bucket}/{source_key}'...")
        # # 2. Delete the original object
        # s3_client.delete_object(
        #     Bucket=source_bucket,
        #     Key=source_key
        # )
        # print("  -> Delete object successful.")
        return True
    
    except Exception as e:
        print(f"  -> S3 Move FAILED for {source_key}: {e}")
        return False

def update_document_key(db_config_full, doc_id, new_s3_key):
    """
    Updates the S3Key for a specific document ID in the database.
    NOTE: db_config_full includes the 'table' key, which must be filtered out for the connection.
    """
    conn = None
    cursor = None

    # Separate connection parameters from the table name
    table_name = db_config_full['table']
    connection_config = {k: v for k, v in db_config_full.items() if k != 'table'}

    try:
        # Connect using only valid connection parameters
        conn = mysql.connector.connect(**connection_config)
        cursor = conn.cursor()
        
        # Prepare the UPDATE query
        update_query = (
            f"UPDATE {table_name} SET S3Key = %s WHERE ID = %s"
        )
        
        cursor.execute(update_query, (new_s3_key, doc_id))
        
        # Commit the transaction to apply the changes
        conn.commit()
        print(f"  -> DB Update SUCCESS for ID {doc_id}.")
        return True
        
    except mysql.connector.Error as err:
        print(f"  -> DB Update FAILED for ID {doc_id}: {err}. Rolling back.")
        if conn:
            conn.rollback()
        return False
        
    finally:
        if cursor:
            cursor.close()
        if conn and conn.is_connected():
            conn.close()