# report.py
import csv

def read_portfolio(filename):
    '''
    Read a stock portfolio file into a list of dictionaries with keys
    name, shares, and price.
    '''
    portfolio = []
    with open(filename) as f:
        rows = csv.reader(f)
        headers = next(rows)

        for row in rows:
            stock = {
                 'name'   : row[0],
                 'shares' : int(row[1]),
                 'price'   : float(row[2])
            }
            portfolio.append(stock)

    return portfolio

def read_prices(filename):
    '''
    Read a CSV file of price data into a dict mapping names to prices.
    '''
    prices = {}
    with open(filename) as f:
        rows = csv.reader(f)
        for row in rows:
            try:
                prices[row[0]] = float(row[1])
            except IndexError:
                pass

    return prices

portfolio = read_portfolio('../../Work/Data/portfolio.csv')
prices    = read_prices('../../Work/Data/prices.csv')

# Calculate the total cost of the portfolio
total_cost = 0.0
for s in portfolio:
    total_cost += s['shares']*s['price']

print('Total cost', total_cost)

# Compute the current value of the portfolio
total_value = 0.0
for s in portfolio:
    total_value += s['shares']*prices[s['name']]

print('Current value', total_value)
print('Gain', total_value - total_cost)