from airflow import DAG
from airflow.operators.python import PythonOperator
from airflow.providers.oracle.hooks.oracle import OracleHook
from airflow.utils.dates import days_ago
from datetime import timedelta
import logging


p_run_id = 1234
p_service_name = 'MyService'
p_table_owner = 'MY_SCHEMA'
p_table_name = 'MY_TABLE'
p_objectstore_uri = 's3://bucket/uri'  # subject to change appropriate for RAR/MOPDB


def start_log_table_task(**context):
    proc_call = "BEGIN MRDS_LOADER.DATA_REPLICATOR.start_log_table(:1, :2, :3, :4); END;"
    try:
        oracle_hook = OracleHook(oracle_conn_id='oracle_default')
        conn = oracle_hook.get_conn()
        cursor = conn.cursor()
        cursor.execute(proc_call, [p_run_id, p_service_name, p_table_owner, p_table_name])
        conn.commit()
        cursor.close()
        conn.close()
        logging.info("start_log_table executed successfully.")
    except Exception as e:
        logging.error("Failed to execute start_log_table: %s", e, exc_info=True)
        raise

def export_table_task(**context):
    proc_call = "BEGIN MRDS_LOADER.DATA_REPLICATOR.export_table(:1, :2, :3, :4); END;"
    try:
        oracle_hook = OracleHook(oracle_conn_id='oracle_default')
        conn = oracle_hook.get_conn()
        cursor = conn.cursor()
        cursor.execute(proc_call, [p_service_name, p_table_owner, p_table_name, p_objectstore_uri])
        conn.commit()
        cursor.close()
        conn.close()
        logging.info("export_table executed successfully.")
    except Exception as e:
        logging.error("Failed to execute export_table: %s", e, exc_info=True)
        raise

def devo_impyla_task(**context):
    # Placeholder for Impyla (Devo) code
    # Example for future:
    # from impala.dbapi import connect
    # conn = connect(host="...", port=21050)
    # cursor = conn.cursor()
    # cursor.execute("...")
    logging.info("Impyla (Devo) task placeholder ran. Please implement.")

def end_log_table_task(**context):
    proc_call = "BEGIN MRDS_LOADER.DATA_REPLICATOR.end_log_table(:1, :2, :3); END;"
    try:
        oracle_hook = OracleHook(oracle_conn_id='oracle_default')
        conn = oracle_hook.get_conn()
        cursor = conn.cursor()
        cursor.execute(proc_call, [p_service_name, p_table_owner, p_table_name])
        conn.commit()
        cursor.close()
        conn.close()
        logging.info("end_log_table executed successfully.")
    except Exception as e:
        logging.error("Failed to execute end_log_table: %s", e, exc_info=True)
        raise


default_args = {
    'owner': 'airflow',
    'depends_on_past': False,
    'start_date': days_ago(1),
    'email_on_failure': False,
    'email_on_retry': False,
    'retries': 2,
    'retry_delay': timedelta(minutes=5),
}


with DAG(
    dag_id='rqsd_devo_replicator_test_old',
    default_args=default_args,
    description='Run Devo replicator workflow',
    schedule_interval=None,
    catchup=False,
    tags=['Devo', 'RQSD', 'Replicator'],
) as dag:

    t1 = PythonOperator(
        task_id='start_log_table',
        python_callable=start_log_table_task,
    )

    t2 = PythonOperator(
        task_id='export_table',
        python_callable=export_table_task,
    )

    t3 = PythonOperator(
        task_id='devo_impyla',
        python_callable=devo_impyla_task,
    )

    t4 = PythonOperator(
        task_id='end_log_table',
        python_callable=end_log_table_task,
    )

    t1 >> t2 >> t3 >> t4