import perf
from six.moves import xrange

from sqlalchemy import Column, ForeignKey, Integer, String
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import relationship, sessionmaker
from sqlalchemy import create_engine


Base = declarative_base()


class Person(Base):
    __tablename__ = 'person'
    # Here we define columns for the table person
    # Notice that each column is also a normal Python instance attribute.
    id = Column(Integer, primary_key=True)
    name = Column(String(250), nullable=False)


class Address(Base):
    __tablename__ = 'address'
    # Here we define columns for the table address.
    # Notice that each column is also a normal Python instance attribute.
    id = Column(Integer, primary_key=True)
    street_name = Column(String(250))
    street_number = Column(String(250))
    post_code = Column(String(250), nullable=False)
    person_id = Column(Integer, ForeignKey('person.id'))
    person = relationship(Person)


# Create an engine that stores data in the local directory's
# sqlalchemy_example.db file.
engine = create_engine('sqlite://')

# Create all tables in the engine. This is equivalent to "Create Table"
# statements in raw SQL.
Base.metadata.create_all(engine)


# Bind the engine to the metadata of the Base class so that the
# declaratives can be accessed through a DBSession instance
Base.metadata.bind = engine

DBSession = sessionmaker(bind=engine)
# A DBSession() instance establishes all conversations with the database
# and represents a "staging zone" for all the objects loaded into the
# database session object. Any change made against the objects in the
# session won't be persisted into the database until you call
# session.commit(). If you're not happy about the changes, you can
# revert all of them back to the last commit by calling
# session.rollback()
session = DBSession()


# add 'npeople' people to the database

def bench_sqlalchemy(loops, npeople):
    total_dt = 0.0

    for loops in xrange(loops):
        # drop rows created by the previous benchmark
        session.query(Person).delete(synchronize_session=False)
        session.query(Address).delete(synchronize_session=False)

        # Run the benchmark once
        t0 = perf.perf_counter()

        for i in xrange(npeople):
            # Insert a Person in the person table
            new_person = Person(name="name %i" % i)
            session.add(new_person)
            session.commit()

            # Insert an Address in the address table
            new_address = Address(post_code='%05i' % i, person=new_person)
            session.add(new_address)
            session.commit()

        # do 100 queries per insert
        for i in xrange(npeople):
            session.query(Person).all()

        total_dt += (perf.perf_counter() - t0)

    return total_dt


def add_cmdline_args(cmd, args):
    cmd.extend(("--rows", str(args.rows)))


if __name__ == "__main__":
    runner = perf.Runner(add_cmdline_args=add_cmdline_args)
    runner.metadata['description'] = ("SQLAlchemy Declarative benchmark "
                                      "using SQLite")
    runner.argparser.add_argument("--rows", type=int, default=100,
                                  help="Number of rows (default: 100)")

    args = runner.parse_args()
    runner.bench_time_func('sqlalchemy_declarative', bench_sqlalchemy,
                           args.rows)
