"""
mysql is a dbx module for the MySQL database server.

mysql requires the DB-API MySQLdb module.
"""


import MySQLdb as _mysql


def escape(value):
    if isinstance(value, basestring):
        return _mysql.escape_string(value)
    elif isinstance(value, (int, long)):
        return value
    else:
        raise TypeError


def escapeAll(values):
    return _mysql.escape_sequence(values)


class Error(Exception):
    pass


class SQLError(Error):
    pass


class MySQL:
    C_NAME = 0
    C_TYPE = 1
    C_NULL = 2
    C_DEFAULT = 3

    def __init__(self, dbname=None, *args):
        if dbname is not None:
            self.connect(dbname, *args)

    def __del__(self):
        try:
            self.close()
        except:
            pass

    def connect(self, dbname, hostname="localhost",
                username="", password=""):
        try:
            self.conn = _mysql.connect(db=dbname, host=hostname,
                                       user=username, passwd=password)
        except _mysql.Error, e:
            raise Error, "%i: %s" % (e.args[0], e.args[1])
        self.cursor = self.conn.cursor(_mysql.cursors.DictCursor)

    def selectDB(self, dbname):
        try:
            self.conn.select_db(dbname)
        except _mysql.Error, e:
            raise Error, "%i: %s" % (e.args[0], e.args[1])

    def close(self):
        self.cursor.close()
        self.conn.close()

    def query(self, sql):
        try:
            self.cursor.execute(sql)
        except _mysql.Error, e:
            raise SQLError, ("%i: %s" % (e.args[0], e.args[1]), sql)
        if self.cursor.rowcount == -1:
            return None
        return self.cursor.rowcount

    def rowQuery(self, sql):
        self.query(sql)
        return self.cursor.fetchone()

    def listQuery(self, sql):
        self.query(sql)
        return self.cursor.fetchall()

    def queryID(self):
        return self.cursor.lastrowid

    def version(self):
        return self.conn.get_server_info()

    def tables(self):
        tables = self.listQuery("SHOW TABLES")
        return [i.values()[0] for i in tables]

    def columns(self, table):
        sql = "SHOW COLUMNS FROM `%s`" % escape(table)
        columns = self.listQuery(sql)
        ret = []
        for i in columns:
            null = i["Null"] == "YES"
            ret.append((i["Field"], i["Type"], null, i["Default"]))
        return ret