import sys
import os
from airflow import DAG
from airflow.operators.python import PythonOperator
from airflow.utils.dates import days_ago
from datetime import datetime, timedelta
import logging

### DEVO CONNECTOR WITH DYNAMIC WORKFLOW CONTEXT & HISTORY KEY

# Importing custom modules
sys.path.append('/opt/airflow/python/connectors/devo')
sys.path.append('/opt/airflow/python/connectors/devo')

sys.path.append('/opt/airflow/python/mrds_common')
sys.path.append('/opt/airflow/src/airflow/dags/ods/rqsd')


# Import your functions from manage_runs and devo_connector as before
from mrds.utils.manage_runs import init_workflow, finalise_workflow
from devo_connector import main as devo_main

default_args = {
    'owner': 'airflow',
    'depends_on_past': False,
    'start_date': days_ago(1),
    'email_on_failure': False,
    'email_on_retry': False,
    'retries': 3,
    'retry_delay': timedelta(minutes=5),
}

# dynamic name extracton from basename
dag_id = os.path.splitext(os.path.basename(__file__))[0]

with DAG(
    dag_id=dag_id,
    default_args=default_args,
    description='Run devo RQSD data ingestion workflow',
    schedule_interval=None,
    catchup=False,
    tags=["Devo", "RQSD", "Connector"],
) as dag:

    def run_devo_connector_rqsd(**context):
        try:
            env = os.getenv("MRDS_ENV")
            username = os.getenv("MRDS_LOADER_DB_USER")
            password = os.getenv("MRDS_LOADER_DB_PASS")
            tnsalias = os.getenv("MRDS_LOADER_DB_TNS")
            if not all([username, password, tnsalias]):
                raise ValueError(
                    "Missing one or more required environment variables: "
                    "MRDS_LOADER_DB_USER, MRDS_LOADER_DB_PASS, MRDS_LOADER_DB_TNS"
                )

            logging.info(f"Starting Casper RQSD workflow from Airflow DAG for env '{env}'")
            print("======== THIS ... =========")
            print("======== THIS ... =========")
            database_name = 'MOPDB'
            workflow_name = 'w_MOPDB_RQSD_PROCESS'
            workflow_run_id = str(context['ti'].run_id)

            a_workflow_history_key = init_workflow(database_name, workflow_name, workflow_run_id)
            logging.info(f"Initialized workflow with history key: {a_workflow_history_key}")

            workflow_context = {
                "run_id": workflow_run_id,
                "a_workflow_history_key": a_workflow_history_key
            }

            flow_config_path = "/opt/airflow/src/airflow/dags/ods/rqsd/rqsd_process/config/yaml/flow_config_rqsd_observations.yaml"
            env_config_path = "/opt/airflow/python/connectors/devo/config/env_config_rqsd.yaml"

            logging.info("Starting Devo RQSD workflow from Airflow DAG")
            devo_main(workflow_context, flow_config_path, env_config_path, env)
            logging.info("Devo RQSD workflow completed successfully")

            # Push the workflow history key to XCom for downstream tasks
            context['ti'].xcom_push(key='workflow_history_key', value=a_workflow_history_key)

        except Exception as e:
            logging.error(f"Error running Devo RQSD workflow: {e}", exc_info=True)
            # If init_workflow succeeded but workflow failed, finalize with FAILED status
            # Attempt to retrieve the key to finalize
            if 'a_workflow_history_key' in locals():
                try:
                    finalise_workflow(a_workflow_history_key, "FAILED")
                except Exception as finalise_error:
                    logging.error(f"Failed to finalise workflow after error: {finalise_error}")
            raise

    def finalise_workflow_task(**context):
        # Pull the workflow_history_key from XCom pushed by the main task
        ti = context['ti']
        a_workflow_history_key = ti.xcom_pull(key='workflow_history_key', task_ids='run_devo_connector_rqsd')

        if a_workflow_history_key is None:
            raise ValueError("No workflow history key found in XCom; cannot finalise workflow")

        # Call finalise with SUCCESS status
        finalise_workflow(a_workflow_history_key, "SUCCESS")
        logging.info(f"Finalised workflow with history key {a_workflow_history_key} as SUCCESS")

    run_devo = PythonOperator(
        task_id='run_devo_connector_rqsd',
        python_callable=run_devo_connector_rqsd,
        provide_context=True,
    )

    finalize = PythonOperator(
        task_id='finalise_workflow',
        python_callable=finalise_workflow_task,
        provide_context=True,
    )

    run_devo >> finalize