import os

from dotenv import load_dotenv
from mysql.connector import Error, connect, errorcode

load_dotenv()

db_host = os.environ.get("DB_HOST")
db_user = os.environ.get("DB_USER")
db_password = os.environ.get("DB_PASSWORD")
db_name = os.environ.get("DB_NAME")

try:
    connection = connect(
        host= db_host,
        user= db_user,
        password= db_password,
        database= db_name
    ) 
    
    cursor = connection.cursor()
    ### Exemple 1 : commande
    # cursor.execute("SELECT * FROM employee LIMIT 5")
    # results = cursor.fetchone()
    # print(results)

    # ### Exemple 2 : requête complète comme variable
    # query = """
    # CREATE TABLE IF NOT EXISTS movies (
    # id INT AUTO_INCREMENT PRIMARY KEY,
    # title VARCHAR(100),
    # release_year YEAR(4),
    # genre VARCHAR(100),
    # collection_in_mil DECIMAL(4,1)
    # )
    # """
    # cursor.execute(query)
    # # CIUD : Create, Insert, Update, Delete => Commit
    # connection.commit()

    ### Exemple 3 : multiple requête
    insert_query = """
    INSERT INTO movies (title, release_year, genre, collection_in_mil)
    VALUES
        ("Forrest Gump", 1994, "Drama", 330.2),
        ("INception", 2010, "Aventure", 293.7),
        ("Titanic", 1995, "Drama", 530.4)
    """

    create_query = """
    CREATE TABLE IF NOT EXISTS reviewers (
    id INT AUTO_INCREMENT PRIMARY KEY,
    firstname VARCHAR(100),
    lastname VARCHAR(100)
    )
    """

    insert_query_2 = """
    INSERT INTO reviewers (firstname, lastname)
    VALUES (%s, %s)
    """

    reviewers = [
        ("Jean", "FAIBLE"),
        ("Alain", "TERIEUR"),
        ("Tabatha", "CLOISON"),
        ("Ahmed", "BIEN")
    ]

    cursor.execute(insert_query)
    cursor.execute(create_query)
    cursor.executemany(insert_query_2, reviewers)
    connection.commit()
    
    cursor.execute("SELECT * FROM movies")
    # lire un par un
    resultat = cursor.fetchone()
    print(resultat)
    while resultat is not None:
        print(resultat)
        resultat = cursor.fetchone()

    # utilisation de lot
    cursor.execute("SELECT * FROM movies")
    batch = cursor.fetchmany(size= 4)
    while batch:
        print("----")
        for row in batch:
            print(row)
        batch = cursor.fetchmany(4)

    # Out of Memory

    insert_movies_query = """
    INSERT INTO movies (title, release_year, genre, collection_in_mil)
    VALUES (%s, %s, %s, %s) 
    """

    with open("movies.csv", "r") as fichier:
        reader = csv.reader(fichier)
        next(reader)

except Error as error:
    match error.errno:
        case errorcode.ER_ACCESS_DENIED_ERROR:
            print("Accès refusé. Vérifier USER et PASSWORD")
        case errorcode.ER_BAD_DB_ERROR:
            print("BDD n'existe pas")
        case _:
            print(f"Erreur {error}")
finally:
    if cursor is not None:
        cursor.close()
    if connection is not None and connection.is_connected():
        connection.close()