import time
import psycopg2

def connect_postgres():
    return psycopg2.connect(
        host="localhost",
        database="postgres",
        user="postgres",
        password="1"
    )

def create_tables():
    sql_command_create_table= (
        """CREATE TABLE airlines
        (
            IATA_CODE VARCHAR(2),
            AIRLINE VARCHAR(30)
        )
        """,
        """CREATE TABLE airports
        (
            IATA_CODE VARCHAR(3),
            AIRPORT VARCHAR(100),
            CITY VARCHAR(40),
            STATE VARCHAR(2),
            COUNTRY VARCHAR(40),
            LATITUDE REAL,
            LONGITUDE REAL
        )
        """,
        """CREATE TABLE flights
        (
            YEAR INTEGER,
            MONTH INTEGER,
            DAY INTEGER,
            DAY_OF_WEEK INTEGER,
            AIRLINE VARCHAR(2),
            FLIGHT_NUMBER INTEGER,
            TAIL_NUMBER VARCHAR(6),
            ORIGIN_AIRPORT VARCHAR(5),
            DESTINATION_AIRPORT VARCHAR(5),
            SCHEDULED_DEPARTURE INTEGER,
            DEPARTURE_TIME INTEGER,
            DEPARTURE_DELAY INTEGER,
            TAXI_OUT INTEGER,
            WHEELS_OFF INTEGER,
            SCHEDULED_TIME INTEGER,
            ELAPSED_TIME INTEGER,
            AIR_TIME INTEGER,
            DISTANCE INTEGER,
            WHEELS_ON INTEGER,
            TAXI_IN INTEGER,
            SCHEDULED_ARRIVAL INTEGER,
            ARRIVAL_TIME INTEGER,
            ARRIVAL_DELAY INTEGER,
            DIVERTED INTEGER,
            CANCELLED INTEGER,
            CANCELLATION_REASON VARCHAR(1),
            AIR_SYSTEM_DELAY INTEGER,
            SECURITY_DELAY INTEGER,
            AIRLINE_DELAY INTEGER,
            LATE_AIRCRAFT_DELAY INTEGER,
            WEATHER_DELAY INTEGER
        )
        """)
    try:
        with connect_postgres() as conn:
            with conn.cursor() as cursor:
                for command in sql_command_create_table:
                    cursor.execute(command)
            conn.commit()
            cursor.close()
        conn.close()
    except (psycopg2.DatabaseError, Exception) as error:
        print(error)


def create_data():
    sql_command_copy =(
        """COPY airlines FROM 'C://Users//Public//2015_Flight_Delay_and_cancellations//airlines.csv' DELIMITER ',' NULL AS ''""",
        """COPY airports FROM 'C://Users//Public//2015_Flight_Delay_and_cancellations//airports.csv' DELIMITER ',' NULL AS ''""",
        """COPY flights FROM 'C://Users//Public//2015_Flight_Delay_and_cancellations//flights.csv' DELIMITER ',' NULL AS ''""")
    try:
        with connect_postgres() as conn:
            with conn.cursor() as cursor:
                for command in sql_command_copy:
                    cursor.execute(command)
            conn.commit()
            cursor.close()
        conn.close()
    except (psycopg2.DatabaseError, Exception) as error:
        print(error)


def requete_lecture(str):
    try:
        with connect_postgres() as conn:
            with conn.cursor() as cursor:
                start = time.time()
                cursor.execute(str)
            conn.commit()
            temps = time.time() -start
            print("Cette requête prends:", temps, "seconde")
            cursor.close()
        conn.close()
    except (psycopg2.DatabaseError, Exception) as error:
        print(error)