expense-tracker.py

"""
The view function only uses one search parameter at a time and is unable to use more than one filter. This is something I'll work on later by redesigning how the viewby function works. I would like to think that the solve for this would be to use a results list, similar to how I have within it for exporting results to a file. I could then get it to add or remove items from that list if they don't match the users filters. I.e. populate the temporary list variable with all the expenses in there as each list item. Then take many parameters from the user i.e. date and description and for each item that doesn't match those queries remove them from that list and then use the export function to save to file.
"""

import os
import sys
from datetime import datetime
import csv
import time
import argparse

# Global Variables:
FILE = "expenses.csv"


def on_load():
    clear_screen()
    # AI did help me make this as this was my first use of argparse. While it didn't give me the code for it, I used AI to tell me what sort of functions this module uses and how to use it correctly within my script. After spending some time on an external file and knowing how it works. I made some edits to it and then imported it on. This is a really useful feature for commmand line utilities or tools that you can build on Python
    parser = argparse.ArgumentParser(
        prog="expense-tracker.py",
        formatter_class=argparse.ArgumentDefaultsHelpFormatter,
        description=f"Welcome to the Python Expense Tracker CLI. This program was made as part of one of the projects in Roadmap.sh to learn the Python programming language.",
        epilog="Use -h for help. GitHub: Sheikh-H",
    )

    subparsers = parser.add_subparsers(required=True, dest="InitialCommand")
    add_parser = subparsers.add_parser(
        name="add",
        help="Add a new expense - 4 positional arguments [--description, --amount, --date, --category]",
    )
    add_parser.add_argument("--description", required=True, type=str)
    add_parser.add_argument("--amount", required=True, type=float)
    add_parser.add_argument("--category", required=True, type=str)
    add_parser.add_argument("--date", required=True, type=str)

    update_parser = subparsers.add_parser(
        name="update",
        help="Update an existing expense - 4 optional arguments [--id OR --description] followed by one or more of these: [--newdescription, --amount, --date, --category]",
    )
    update_parser.add_argument("--id", type=int)
    update_parser.add_argument("--description", type=str)
    update_parser.add_argument("--newdescription", type=str)
    update_parser.add_argument("--amount", type=float)
    update_parser.add_argument("--category", type=str)
    update_parser.add_argument("--date", type=str)

    delete_parser = subparsers.add_parser(
        name="delete",
        help="Delete an expense - 1 of 2 optional arguments [--id, --description]",
    )
    delete_parser_group = delete_parser.add_mutually_exclusive_group(required=True)

    delete_parser_group.add_argument("--description", type=str)
    delete_parser_group.add_argument("--id", type=int)

    view_parser = subparsers.add_parser(
        name="view",
        help="View expenses - 9 optional arguments [--id, --description, --category, --amount, --date, --day, --month, --year]",
    )
    view_parser.add_argument("--description", required=False, type=str)
    view_parser.add_argument("--amount", required=False, type=float)
    view_parser.add_argument("--category", required=False, type=str)
    view_parser.add_argument("--date", required=False, type=str)
    view_parser.add_argument("--id", required=False, type=int)

    view_parser.add_argument("--month", required=False, type=str)
    view_parser.add_argument("--year", required=False, type=str)
    view_parser.add_argument("--day", required=False, type=str)

    return parser, parser.parse_args()


def error_messages(*messages):
    clear_screen()
    for message in messages:
        print(message)
        time.sleep(0.5)
    time.sleep(3)
    clear_screen()
    exit()


def load_file(file=FILE):
    fieldnames = ["ID", "Date", "Description", "Amount", "Category"]
    if not os.path.exists(file):
        with open(file, "w") as f:
            writer = csv.DictWriter(f, fieldnames=fieldnames, dialect="excel")
            writer.writeheader()
    with open(file, "r") as f:
        data = csv.DictReader(f, dialect="excel")
        return list(data)


def save_data(DATA, file=FILE):
    fieldnames = ["ID", "Date", "Description", "Amount", "Category"]
    with open(file, "w", newline="") as f:
        writer = csv.DictWriter(f, fieldnames=fieldnames)
        writer.writeheader()
        for field in DATA:
            writer.writerow(field)


def clear_screen():
    os.system("cls" if os.name == "nt" else "clear")


def add_expense(description, amount, category, date):
    DATA = load_file()
    new_id = max(int(row["ID"]) for row in DATA) + 1 if DATA else 1

    try:
        formatted_date = datetime.strptime(date, "%d-%m-%Y").date()
    except:
        error_messages("Please re-enter the date in the following format 'dd-mm-yyy'")

    new_expense = {
        "ID": new_id,
        "Description": description,
        "Amount": amount,
        "Category": category.upper(),
        "Date": formatted_date,
    }

    DATA.append(new_expense)

    save_data(DATA, FILE)
    error_messages(
        f"Added '{description}' under '{category}' for the amount of £{amount:.2f} at {formatted_date}!"
    )


def delete_expense(expense_id, description):
    DATA = load_file()
    expense = []
    if expense_id != None:
        for i, row in enumerate(DATA):
            if int(row["ID"]) == expense_id:
                expense.append(row.copy())
                del DATA[i]
                break
    if description != None:
        counter = 0
        for i, row in enumerate(DATA):
            if str(row["Description"]).lower() == str(description).lower():
                counter += 1
        if counter == 1:
            for i, row in enumerate(DATA):
                if str(row["Description"]).lower() == description.lower():
                    expense.append(row.copy())
                    del DATA[i]
                    break
        else:
            print(
                "You have more than one expense with the same description, please use ID field instead!"
            )
            print("Here is a list of all expenses with the same description:")
            for i, row in enumerate(DATA):
                if str(row["Description"]).lower() == description.lower():
                    print("-" * 50)
                    print(f"ID: {row['ID']}\t\t\t\tDate: {row['Date']}")
                    print(f"Description: {row['Description']}")
                    print(f"Category: {row['Category']}")
                    print(f"Amount: £{row['Amount']}")
    save_data(DATA, FILE)
    if expense:
        print(f"Expense '{expense[0]['Description']}' Deleted!")
    else:
        error_messages("Unable to delete this, try again")


def update_expense(
    expense_id, description, new_description, new_amount, new_date, new_category
):
    expense_list = []
    DATA = load_file()
    if expense_id is not None and description is not None:
        error_messages(
            "Please use either expense id or expense description to search, refer to manual [-h]"
        )
    if expense_id is not None:
        for i, row in enumerate(DATA):
            if int(row["ID"]) == expense_id:
                expense_list.append(row.copy())
                if new_description != None:
                    print(row["Description"])
                    row["Description"] = new_description
                if new_amount != None:
                    row["Amount"] = new_amount
                if new_date != None:
                    formatted_date = datetime.strptime(new_date, "%d/%m/%Y").date()
                    row["Date"] = formatted_date
                if new_category != None:
                    row["Category"] = new_category
                break
    if description is not None:
        count = 0
        for row in DATA:
            if row["Description"].lower().strip() == description.lower().strip():
                count += 1
        if count > 1:
            print(
                f"You have {count} expenses with the same description, please use expense id"
            )
            print("Here is a list of all the expenses with the same description:")
            for row in DATA:
                if row["Description"].lower().strip() == description.lower().strip():
                    print("-" * 50)
                    print(f"ID: {row['ID']}\t\t\t\tDate: {row['Date']}")
                    print(f"Description: {row['Description']}")
                    print(f"Category: {row['Category']}")
                    print(f"Amount: £{row['Amount']}")
        if count == 1:
            for i, row in enumerate(DATA):
                if row["Description"].lower().strip() == description.lower().strip():
                    expense_list.append(row.copy())
                    if new_description != None:
                        row["Description"] = new_description.strip()
                    if new_amount != None:
                        row["Amount"] = new_amount
                    if new_category != None:
                        row["Category"] = new_category.strip()
                    if new_date != None:
                        formatted_date = datetime.strptime(new_date, "%d/%m/%Y").date()
                        row["Date"] = formatted_date
                    break
    save_data(DATA, FILE)
    if expense_list:
        error_messages(f"Expense '{expense_list[0]['Description']}' has been updated!")
    else:
        error_messages("Unable to update this expense, please try again!")


def view_all():
    DATA = load_file()
    clear_screen()
    print("Here is a list of all your expenses: ")
    time.sleep(2)
    for row in DATA:
        print("-" * 50)
        print(f"ID: {row['ID']}\t\t\t\tDate: {row['Date']}")
        print(f"Description: {row['Description']}")
        print(f"Category: {row['Category']}")
        print(f"Amount: £{row['Amount']}")


def export_to_csv(expenses):
    # This function needs fixing, the parameters passed into it should be what is used from the view function. After someone views their expenses using a certain filter, they should be presented with the option to save to file for that result.
    option = (
        input("Would you like to export this result to a csv file? ").lower().strip()
    )
    if option == "yes":
        fieldnames = ["ID", "Date", "Description", "Amount", "Category"]
        with open("filtered_expense.csv", "w") as f:
            writer = csv.DictWriter(f, fieldnames=fieldnames)
            writer.writeheader()
            for key, value in enumerate(
                expenses
            ):  # When taking my code through AI it suggested that I shouldn't enumerate and separate key, value pairs and store like this. But my original version did have that method and it didn't work which is why i opted to use this method and it worked fine. This is my code nevertheless and would like to keep it so anyone else can view and criticise and help me improve.
                writer.writerow(value)
    else:
        exit()


def view_by(
    expense_id=None,
    description=None,
    category=None,
    month=None,
    year=None,
    day=None,
    date=None,
):
    DATA = load_file()
    results = []
    if expense_id is not None:
        print("Here is the expenses with that ID:")
        time.sleep(2)
        for row in DATA:
            if int(row["ID"]) == expense_id:
                results.append(row)
                print(row)
        export_to_csv(results)
    if description is not None:
        print("Here is the expenses with that description:")
        time.sleep(2)
        for row in DATA:
            if row["Description"].lower() == description.lower():
                results.append(row)
                print(row)
        export_to_csv(results)
    if category is not None:
        print(f"Here are the expenses in '{category}':")
        time.sleep(2)
        for row in DATA:
            if row["Category"].lower() == category.lower().strip():
                results.append(row)
                print(row)
        export_to_csv(results)
    if date is not None:
        print(f"Here are the expenses made on '{date}'")
        formatted_date = datetime.strptime(date, "%d-%m-%Y").date()
        time.sleep(2)
        for row in DATA:
            if datetime.strptime(row["Date"], "%Y-%m-%d").date() == formatted_date:
                print(row)
                results.append(row)
        export_to_csv(results)
    if year is not None:
        print(f"Here are all the expenses made in year '{year}'")
        formatted_year = datetime.strptime(year, "%Y").year
        time.sleep(2)
        for row in DATA:
            if datetime.strptime(row["Date"], "%Y-%m-%d").year == formatted_year:
                print(row)
                results.append(row)
        export_to_csv(results)
    if day is not None:
        str_day = ""
        if day == "1":
            str_day = "st"
        elif day == "2":
            str_day = "nd"
        elif day == "3":
            str_day = "rd"
        else:
            str_day = "nth"
        print(f"Here are all the expenses made on the '{day}{str_day}'")
        formatted_day = datetime.strptime(day, "%d").day
        time.sleep(2)
        for row in DATA:
            if datetime.strptime(row["Date"], "%Y-%m-%d").day == formatted_day:
                print(row)
                results.append(row)
        export_to_csv(results)
    if month is not None:
        if month.isdigit():
            formatted_month = datetime.strptime(month, "%m").month
            month_name = datetime.strptime(month, "%m").strftime("%B")

            print(f"Here are all the expenses made in '{month_name}':")
            time.sleep(2)

            for row in DATA:
                if datetime.strptime(row["Date"], "%Y-%m-%d").month == formatted_month:
                    print(row)
                    results.append(row)
            export_to_csv(results)

        else:
            if len(month) > 3:
                formatted_month = datetime.strptime(month, "%B").month

                print(f"Here are all the expenses made in '{month.title()}':")
                time.sleep(2)

                for row in DATA:
                    if (
                        datetime.strptime(row["Date"], "%Y-%m-%d").month
                        == formatted_month
                    ):
                        print(row)
                        results.append(row)
                export_to_csv(results)

            elif len(month) == 3:
                formatted_month = datetime.strptime(month, "%b").month
                month_name = datetime.strptime(month, "%b").strftime("%B")

                print(f"Here are all the expenses made in '{month_name}':")
                time.sleep(2)

                for row in DATA:
                    if (
                        datetime.strptime(row["Date"], "%Y-%m-%d").month
                        == formatted_month
                    ):
                        print(row)
                        results.append(row)
                export_to_csv(results)


def main():
    parser, args = on_load()
    if args.InitialCommand == "add":
        if not [args.description, args.amount, args.category, args.date]:
            print(
                parser.error(
                    "Please enter all the fields needed to generate a new expense!"
                )
            )
        else:
            add_expense(args.description, args.amount, args.category, args.date)
    elif args.InitialCommand == "delete":
        if not any([args.id, args.description]):
            print(
                parser.error(
                    "Please enter the ID or description of the expense you would like to delete!"
                )
            )
        else:
            delete_expense(args.id, args.description)
    elif args.InitialCommand == "update":
        if not any(
            [
                args.amount,
                args.category,
                args.date,
                args.newdescription,
            ]
        ):
            print(
                parser.error(
                    "Please enter the fields that you would like to update for this expense!"
                )
            )
        else:
            update_expense(
                args.id,
                args.description,
                args.newdescription,
                args.amount,
                args.date,
                args.category,
            )
    elif args.InitialCommand == "view":
        if not any(
            [
                args.id,
                args.description,
                args.category,
                args.date,
                args.day,
                args.month,
                args.year,
            ]
        ):
            view_all()
        elif args.id:
            view_by(args.id)
        elif args.description:
            view_by(description=args.description)
        elif args.category:
            view_by(category=args.category)
        elif args.date:
            view_by(date=args.date)
        elif args.month:
            view_by(month=args.month)
        elif args.day:
            view_by(day=args.day)
        elif args.year:
            view_by(year=args.year)


if __name__ == "__main__":
    main()