run.py

import gspread
from google.oauth2.service_account import Credentials
from pprint import pprint

SCOPE = [
    "https://www.googleapis.com/auth/spreadsheets",
    "https://www.googleapis.com/auth/drive.file",
    "https://www.googleapis.com/auth/drive"
]

CREDS = Credentials.from_service_account_file('creds.json')
SCOPED_CREDS = CREDS.with_scopes(SCOPE)
GSPREAD_CLIENT = gspread.authorize(SCOPED_CREDS)
SHEET = GSPREAD_CLIENT.open('Love Sandwiches')

def get_sales_data():
    """Get sales figures input from the user.
    Run a while loop to collect valid data from the user
    via the terminal, which must be a string of 6 numbers separated
    by commas. The loop will request data until valid."""
    while True:
        print("Please enter sales data from the last market.")
        print("Data should be six numbers, separated by commas.")
        print("Example: 10,20,30,40,50,60\n")

        data_str = input("Enter your data here: ")

        sales_data = data_str.split(',')

        if validate_data(sales_data):
            print("Data is valid!")
            break

    return sales_data

def validate_data(values):
    """Inside the try, converts strings to integers.
    Raises ValueError if strings can't be converted to integers,
    or if there aren't 6 values."""
    try:
        [int(value) for value in values]
        if len(values) != 6:
            raise ValueError(f"Exactly 6 values required, you provided {len(values)}")
    except ValueError as e:
        print(f"Invalid data: {e}, please try again.\n")
        return False

    return True

def update_worksheet(data, worksheet):
    """Update sales and surplus worksheet, add new rows with the list provided."""
    print(f"Updating {worksheet} worksheet...\n")
    worksheet_to_update = SHEET.worksheet(worksheet)
    worksheet_to_update.append_row(data)
    print(f"{worksheet} worksheet updated successfully!")

def calculate_surplus_data(sales_row):
    """Compare sales with stock and calculate the surplus for each item type.
    The surplus is defined as the sales figure subtracted from the stock:
    -Positive surplus indicates waste
    -Negative surplus indicates extra made when stock was sold out."""

    print("Calculating surplus data...\n")
    stock = SHEET.worksheet('stock').get_all_values()
    stock_row = stock[-1]
    surplus_data = []
    for stock, sales in zip(stock_row, sales_row):
        surplus = int(stock) - sales
        surplus_data.append(surplus)
    
    return surplus_data

def get_last_5_entries_sales():
    """Collects columns of data from sales worksheet collecting the last 5 entries for each sandwich and returns the data as a list of lists."""

    sales = SHEET.worksheet('sales')
    columns = []

    for ind in range(1, 7):
        column = sales.col_values(ind)
        columns.append(column[-5:])
    return columns

def calculate_stock_data(data):
    """Calculate the average stock for each type, adding 10%"""
    print("Calculating stock data...\n")
    new_stock_data = []

    for column in data:
        int_column = [int(num) for num in column]
        average = sum(int_column)/len(int_column)
        stock_num = average * 1.1
        new_stock_data.append(round(stock_num))

    return new_stock_data

def get_stock_values(data):
    headings = SHEET.worksheet('stock').row_values(1)
    dict = {}
    for head, val in zip(headings, data):
        dict.update({head: val})
    return dict

def main():
    """Run all program functions"""
    data = get_sales_data()
    sales_data = [int(num) for num in data]
    new_surplus_data = calculate_surplus_data(sales_data)
    update_worksheet(sales_data, 'sales')
    update_worksheet(new_surplus_data, 'surplus')
    sales_columns = get_last_5_entries_sales()
    stock_data = calculate_stock_data(sales_columns)
    update_worksheet(stock_data, 'stock')
    return stock_data

print("Welcome to Love Sandwiches Data Automation")
stock_data = main()
stock_values = get_stock_values(stock_data)
print("Make the following numbers of sandwiches for next market:\n")
print(stock_values)