"""
Mysql utilities

@author: olivier.massot, 05-2020
"""
import mysql


class MySqlServer:
    def __init__(self, host, port, username, password, description=""):
        self.host = host
        self.port = port
        self.username = username
        self.password = password
        self.description = description or "no description"
        self.cnn = None

    def __repr__(self):
        return f"{self.username}@{self.host}:{self.port} ({self.description})"

    def connect(self):
        self.cnn = mysql.connector.connect(
            host=self.host,
            port=self.port,
            user=self.username,
            passwd=self.password
        )

    def exec(self, sql):
        """ Execute the sql code and return the cursor """
        cursor = self.cnn.cursor()
        logger.debug(sql)
        cursor.execute(sql)
        return cursor

    def db_exists(self, dbname):
        cursor = self.exec(f"""SELECT SCHEMA_NAME
                           FROM INFORMATION_SCHEMA.SCHEMATA
                           WHERE SCHEMA_NAME = '{dbname}'""")
        row = cursor.fetchone()
        return row is not None