utils/database_handler.py

import pandas as pd
import os

CUSTOMERS_FILE = "database/customers.xlsx"

# Ensure database exists
if not os.path.exists("database"):
    os.makedirs("database")
if not os.path.exists(CUSTOMERS_FILE):
    pd.DataFrame(columns=["Name", "Phone", "Email", "Password"]).to_excel(CUSTOMERS_FILE, index=False)

def check_credentials(email, password):
    df = pd.read_excel(CUSTOMERS_FILE)
    user = df[(df["Email"] == email) & (df["Password"] == password)]
    return not user.empty

def save_user(name, phone, email, password):
    df = pd.read_excel(CUSTOMERS_FILE)
    if email in df["Email"].values:
        return False
    new_user = {"Name": name, "Phone": phone, "Email": email, "Password": password}
    df = pd.concat([df, pd.DataFrame([new_user])], ignore_index=True)
    df.to_excel(CUSTOMERS_FILE, index=False)
    return True