parse_emails.py

#!/usr/bin/env python3

import pandas as pd
import re

# Input string
email_str = """
Foo Bar <[email protected]>, [email protected], Alice B. Charlie <[email protected]>, Pete <[email protected]>, Sam Fred Webster Clarke <[email protected]>, [email protected]
"""

# Common suffixes and initials to ignore
SUFFIXES = {"Jr.", "Sr.", "Jr", "Sr"}
INITIALS_REGEX = re.compile(r"^(?:[A-Z]\.|[A-Z]\.[A-Z]\.|[A-Z])$")

# Helper function to parse individual email entry
def parse_email(entry):
    # Match canonical mailbox format: Name <email>
    canonical_match = re.match(r"(.*?)\s*<([^>]+)>", entry)
    if canonical_match:
        display_name = canonical_match.group(1).strip()
        email = canonical_match.group(2).strip()
        first_name, last_name = extract_names(display_name)
    else:
        # If no display name, extract email only
        email = entry.strip()
        first_name, last_name = guess_name_from_email(email)
    
    return {"first_name": first_name, "last_name": last_name, "email": email}

# Helper function to extract names from a display name
def extract_names(display_name):
    tokens = display_name.split()
    
    if len(tokens) == 1:
        # Single token, assume it's the first name
        return tokens[0], "UNK"
    
    first_name = tokens[0]
    remaining_tokens = [token for token in tokens[1:] if not (token in SUFFIXES or INITIALS_REGEX.match(token))]
    
    if remaining_tokens:
        last_name = " ".join(remaining_tokens)
    else:
        last_name = "UNK"
    
    return first_name, last_name

# Helper function to guess name from email
def guess_name_from_email(email):
    username = email.split("@")[0]
    if username.isalpha():
        first_name = username.capitalize()
        last_name = "UNK"
    else:
        first_name = "UNK"
        last_name = "UNK"
    return first_name, last_name

# Split the input string into individual entries
entries = [e.strip() for e in email_str.split(",")]

# Parse all entries
parsed_data = [parse_email(entry) for entry in entries]

# Convert to DataFrame
df = pd.DataFrame(parsed_data)

# Write to CSV
output_file = "parsed_emails.csv"
df.to_csv(output_file, index=False)

print(f"Results written to {output_file}")