def sell(self, ticker, quantity):
"""
SELL stock. checks if a stock exists in the user's positions and
has sufficient shares. creates a new Trade and modifies the Position
as well as adding to the user's balance. returns nothing
"""
trade = Trade()
current_price = get_price(ticker)
mv = current_price * int(quantity)
trade.account_id = self.account_id
trade.volume = quantity
trade.ticker = ticker
trade.price = current_price
trade.market_value = mv * -1
self.balance += mv
self.update_balance()
position = Position()
position.account_id = self.account_id
position.ticker = trade.ticker
stored_position = Position.select_one_where(
'WHERE account_id=? and ticker=?',
(position.account_id, position.ticker))
if stored_position:
position.num_shares = stored_position.num_shares
position.position_id = stored_position.position_id
if stored_position.num_shares < trade.volume or stored_position.num_shares == 0:
transaction_error('Not enough shares')
else:
trade.save()
if stored_position:
position.num_shares = trade.volume
else:
position.num_shares -= trade.volume
position.save()
else:
transaction_error('Ticker {} is invalid'.format(trade.ticker))
def buy(self, ticker, quantity):
"""
BUY stock. checks if a stock exists in the user's positions and
has sufficient shares. creates a new Trade and modifies the Position
as well as adding to the user's balance. returns nothing
"""
trade = Trade()
current_price = get_price(ticker)
mv = current_price * int(quantity)
if self.balance < mv:
transaction_error('Insufficient funds')
else:
trade.account_id = self.account_id
trade.volume = quantity
trade.ticker = ticker
trade.price = current_price
trade.market_value = mv
self.balance -= mv
self.update_balance()
position = Position()
position.account_id = self.account_id
position.ticker = trade.ticker
stored_position = Position.select_one_where(
'WHERE account_id=? and ticker=?',
(position.account_id, position.ticker))
if stored_position:
position.position_id = stored_position.position_id
position.num_shares = stored_position.num_shares
position.num_shares += trade.volume
else:
position.num_shares = trade.volume
trade.save()
position.save()
