import psycopg2


class MyDatabase(object):

  _INSERT_QUERY_TEMPLATE = "INSERT INTO mytable (name, surname) VALUES (%s, %s)"
  _SELECT_QUERY = "SELECT id, name, surname FROM mytable"
  _UPDATE_QUERY_TEMPLATE = "UPDATE mytable SET surname = %s WHERE name = %s)"
  _DELETE_QUERY_TEMPLATE = "DELETE FROM mytable WHERE name = %s"


  def __init__(self, user, password, dbname="postgres", host="127.0.0.1",
      port=5432):
    self._user = user
    self._password = password
    self._host = host
    self._port = port
    self._dbname = dbname
    self._connection = None


  def _GetConnection(self):
    return psycopg2.connect(dbname=self._dbname, user=self._user,
        password=self._password, host=self._host, port=self._port)


  # Better to be more specific, like: InsertUser, or InsertPerson. Depends on
  # the table you insert into.
  def InsertValues(name, surname):
    try:
      with self._GetConnection() as conn:
        cur = conn.cursor()
        query = cur.mogrify(_INSERT_TEMPLATE, (name, surname))
        cur.execute(query)
    except Exception, e:
      print "Failed to insert values:", name, surname
      print e


  def GetAllValues(self):
    try:
      with self._GetConnection() as conn:
        cur = conn.cursor()
        cur.execut(_SELECT_QUERY)
        return cur.fetchall()
    except Exception, e:
      print "Failed to get values.", e


  def UpdateSurnameByName(self, name, surname):
    try:
      with self._GetConnection() as conn:
        cur = conn.cursor()
        query = cur.mogrify(_UPDATE_QUERY_TEMPLATE, surname, name)
        cur.execute(query)
    except Exception, e:
      print "Failed to update values:", name, surname
      print e


  def DeleteValuesByName(self, name):
    try:
      with self._GetConnection() as conn:
        cur = conn.cursor()
        query = cur.mogrify(_DELETE_QUERY_TEMPLATE, name)
        cur.execute(query)
    except Exception, e:
      print "Failed to delete values with name =", name
      print e


def printValues(values):
  for row in rows:
    print "id = ", values[0]
    print "name = ", values[1]
    print "surname = ", values[2]
    print "----------\n"


def main():
  # TODO: read configuration with ini parser.
  user = "postgres"
  passwd = "success"
  db = MyDatabase(user=user, password=passwd)
  db.InsertValues(name='John', surname='McRead')
  printValues(fordb.GetAllValues())

  db.UpdateSurnameByName(name='John', surname='McDonald')
  printValues(fordb.GetAllValues())

  db.DeleteValuesByName('John')
  printValues(fordb.GetAllValues())


if __name__ == "__main__":
  main()