Stock-inventory-system.py

"""
This application implements software to record stock and inventory of a computer store. 

This stock inventory will record manufacturer, quantity of devices, unique serial number and the price of the 
device.This inventory will not allow any negative number in the quantity of item or the price. The price will have 
2 decimal float value, and the quantity will be a whole number only. Application is designed for the user's ease, 
hence initial of each choice will work as well (eg: instead of 'add' you can just type 'a'). All data will be 
non-case sensitive, so it can be searched or typed in any case.

Please note: random is used create unique serial numbers, and tabulate had been used with list of lists to display
the inventory in a table format.

"""

#importing random - unique serial numbers & tabulate to create a neat table format
import random
from tabulate import tabulate 

#defining the function to add the item details and serial_num
def add_item (stock_inventory):
    # prompting user to provide item name
    item_name = input("Enter item name:\t")
    item_name=item_name.capitalize()

    #promting for quantity of the item
    while True:
        item_qty = input("Enter item quantity:\t")
        #convert the item_qty input string to integer
        #this loop will ensure no negative or non-real numbers are added to the quantity
        try:
            item_qty=int(item_qty)
            if item_qty<=0:
                print("Invalid input. Negative or zero values are not acceptable, please type whole number.")
            else:
                break
        except ValueError:
            print("Invalid input. Decimal values are not acceptable. Please enter whole number.")

    #promting user for price of the item
    while True:
        item_price_str=input("Enter item price:\t$")
        #convert the price to 2 decimal floating value
        try:
            item_price_flt=float(item_price_str) #conveting string to float
            if item_price_flt<=0:
                print("Invalid input. Negative or zero values are not acceptable, please type whole number.")
            else:
                #allow float to use only 2 decimals
                item_price= f"${item_price_flt:.2f}"
                break
        except ValueError:
            print("Invalid value. Please enter a valid price.")

    # generate random serial number with initial of the item_name + 4 digit int
    while True:

        random_serial_value=random.randint(1111,9999)
        serial_num=item_name[0].upper()+str(random_serial_value)
        serial_num=unique_serial_num(stock_inventory, serial_num)

        if serial_num != "":
            new_item = [item_name, serial_num, item_qty, item_price]
            stock_inventory.append(new_item) # Append the new item as a list
            display_header = ["Item Name", "Serial Number", "Quantity", "Price"]
            display_inventory = tabulate([new_item], headers=display_header, tablefmt="fancy_grid")
            print("\nBelow item is now added to the inventory:")
            print(display_inventory+"\n")
            return stock_inventory

#verifying if the serial_num generated is unique or not
def unique_serial_num(stock_inventory, serial_num):

    if stock_inventory=="":
        return serial_num
    for each_item in stock_inventory:
        if each_item[1]==serial_num:
            return""
    return serial_num

def application():

    stock_inventory=[]
    hash_break="#"*100

    main_menu=[
        ["Add:","add item in stock"],
        ["Display:","display all items from stock"],
        ["Search:","search item by name in stock"],
        ["End:","end application"]
        ]

    while True:
        #printing main header as per your requirement
        print(hash_break)
        print(tabulate(main_menu,tablefmt="plain")) #printing the menu using tabulate
        print(hash_break)

        select_option=(input("\nEnter your choice:\t")) #get user's input from main_menu options

        #add option will call the function add_item
        if select_option.upper()=="ADD" or select_option.upper()=="A":
            stock_inventory=add_item(stock_inventory)

        #display all the items in the inventory stock
        elif select_option.upper()=="DISPLAY" or select_option.upper()=="D":
            #if inventory is empty, print display_error message
            if len(stock_inventory)==0:
                print("There are no items in stock, please try later...\n")

            #if items are present in inventory, display the items in a table format using tabulate
            else:
                display_header= ["Item Name", "Serial Number", "Quantity","Price"]
                display_inventory = tabulate(stock_inventory, headers=display_header, tablefmt="fancy_grid")
                print(display_inventory)

        #Search functionality based on name of the item
        elif select_option.upper()=="SEARCH" or select_option.upper()=="S":
            #if inventory is empty, print display_search_error message
            if len(stock_inventory)==0:
                print("""There are no items in stock \nplease try again, later...\n""")

            else:
                print("Search item by name......")
                search_by_name= input("Enter name of the item to search:\t") #input variable to search by item_name
                search_by_name=search_by_name.upper() #convert all input to upper case to remove case-insensitivity

                found_item = [each_item for each_item in stock_inventory if search_by_name in each_item[0].upper()]

                if found_item:
                    print("\nSearch results are as below:")
                    display_header=["Item Name", "Serial Number", "Quantity","Price"]
                    print(tabulate(found_item, headers=display_header, tablefmt="fancy_grid"))
                else:
                    #serach error to indicate if the item searched was invalid
                    print(f"The stock does not have {search_by_name}, please try again later...")

        #End the application if "End" selected
        elif select_option.upper()=="END" or select_option.upper()=="E":
            print("Application ending now...\n")
            break

        else:
            print("Enter valid choice.\n")

application()


#***********Code Ends here*********