import csv
import os
def store_data(name: str, email: str, dob: str) -> str:
"""
Registers a new user by saving their name, email, and date of birth (DOB)
to a local CSV file named 'registration.csv'.
Prevents duplicate registrations based on the email address.
Args:
name (str): The name of the user.
email (str): The email address of the user.
dob (str): The date of birth of the user (e.g., 'YYYY-MM-DD').
Returns:
str: A confirmation message indicating whether the registration was successful,
or a message indicating that the user is already registered.
"""
file_path = 'registration.csv'
fieldnames = ['Name', 'email', 'dob']
existing_users = []
file_exists = os.path.isfile(file_path)
# Step 1: Read all existing data if the file exists
if file_exists:
try:
with open(file_path, 'r', newline='') as csvfile:
reader = csv.DictReader(csvfile)
for row in reader:
existing_users.append(row)
except Exception as e:
print(f"Warning: Could not read existing registration.csv: {e}")
# If reading fails, we might proceed, but it's safer to assume no existing users
# or handle this as an error that prevents new registration for safety.
# For now, we'll let it proceed as if no users were read.
# Step 2: Check for duplicates in the read data
for user in existing_users:
if user.get('email', '').lower() == email.lower():
return f"Registration failed: User with email '{email}' is already registered."
# Step 3: If no duplicate, append the new data
try:
# Open in append mode, but handle header writing carefully
with open(file_path, 'a', newline='') as csvfile:
writer = csv.DictWriter(csvfile, fieldnames=fieldnames)
# Write header only if the file was just created (i.e., it didn't exist before)
if not file_exists:
writer.writeheader()
writer.writerow({'Name': name, 'email': email, 'dob': dob})
return f"User '{name}' registered successfully with email '{email}' and DOB '{dob}'."
except Exception as e:
return f"Error registering user '{name}': {e}"
