import cmd
import sqlite3
from textwrap import dedent
import sys

class SqliteShell(cmd.Cmd):

    intro = dedent(f'''
       SQLite version {sqlite3.version}

        Enter "help" for usage hints
    ''')

    prompt = 'sqlite> '

    def __init__(self, filename=None):
        super().__init__()
        self.filename = filename
        self.conn = filename and sqlite3.connect(filename)

    def do_open(self, filename):
        'Connnect to a database using the given filename'
        self.conn = sqlite3.connect(filename)

    def do_select(self, statement):
        'Run a SQL SELECT statement'
        try:
            for row in self.conn.execute(f'SELECT {statement}'):
                print(row)
        except AttributeError:
            print('Need to open a database before running SELECT', file=sys.stderr)
        except sqlite3.OperationalError as e:
            print('sqlite OperationalError:', *e.args, file=sys.stderr)

    def do_quit(self, arg):
        'Exit the shell'
        return True

if __name__ == '__main__':

    SqliteShell().cmdloop()