import os
import yaml
import datetime
import pandas as pd
from  mrds.utils.secrets import  get_secret
import mrds.utils.manage_runs as runManager
import mrds.utils.manage_files as fileManager
import mrds.utils.sql_statements as sqls

import oci

from impala.dbapi import (
    connect,
    ProgrammingError,
    DatabaseError,
    IntegrityError,
    OperationalError,
)
from impala.error import HiveServer2Error


def get_impala_connection(hostname: str, user: str, secret: str):
    conn = connect(
        host=hostname,
        port=443,
        auth_mechanism="PLAIN",
        user=user,
        password=secret,
        use_http_transport=True,
        http_path="cliservice",
        use_ssl=True
        )
    return conn

def execute_query(query: str,user,hostname,password):
    conn = get_impala_connection(hostname, user, password)
    print(conn)
    columns, result = execute_devo_query(query, conn)
    return columns, result

def execute_devo_query(query: str, conn):
    #impersonation_configuration = {"impala.doas.user": userid} # to be changed
    #impersonation_configuration = {} # to be changed
    cursor = conn.cursor()
    print("executing query")
    try:
        cursor.execute(query)
        # Check if the query is a SELECT query (i.e., reads data)
        return None, cursor.rowcount  # rowcount returns the number of rows affected
    except OperationalError as oe:
        raise Exception(
            status_code=500, detail="Failed to connect to Impala: " + str(oe)
        )

    except ProgrammingError as pe:
        raise Exception(status_code=400, detail="Query syntax error: " + str(pe))

    except IntegrityError as ie:
        raise Exception(
            status_code=403, detail="Insufficient permissions: " + str(ie)
        )

    except DatabaseError as db_err:
        raise Exception(status_code=500, detail="Database error: " + str(db_err))

    except HiveServer2Error as au_err:
        raise Exception(
            status_code=403, detail="HiveServer2Error error: " + str(au_err)
        )

    except Exception as e:
        raise Exception(
            status_code=500, detail="An unexpected error occurred: " + str(e)
        ) from e

    finally:
        try:
            if cursor:
                cursor.close()
            if conn:
                conn.close()
        except Exception as e:
            raise Exception(
                status_code=500, detail="Failed to close the connection: " + str(e)
            )

def initialize_task(workflow_context, task_name):
    # Initialize task
    a_task_history_key = runManager.init_task(
        task_name,
        workflow_context["run_id"],
        workflow_context["a_workflow_history_key"],
    )

    return a_task_history_key

def initialize_config(config_file_path): 
    # Ensure the file exists
    if not os.path.exists(config_file_path):
        raise FileNotFoundError(f"Configuration file {config_file_path} not found.")

    # Load the configuration
    with open(config_file_path, "r") as f:
        config_data = yaml.safe_load(f)

    return config_data

def main(env_config_path, env, table, corporate_store):

    #init setup
    envs_info = initialize_config(env_config_path)
    environment_info = envs_info[env]

    try:
        devo_secret_name = environment_info["DEVO_SECRET"]
        password = get_secret(devo_secret_name)
    except:
        print("Failed to retrieve credentials from secrets")    
        raise(Exception)
    # get devo data
    try:
        execute_query(f"INVALIDATE METADATA {corporate_store}.{table}", environment_info['DEVO_USERNAME'], environment_info['IMPALA_HOSTNAME'], password)
        execute_query(f"COMPUTE STATS {corporate_store}.{table}", environment_info['DEVO_USERNAME'], environment_info['IMPALA_HOSTNAME'], password)

    except:
        print("Failed to retrieve DEVO data, error during connection or request")
        raise(Exception)
    return True