preprocessor.py

import pandas as pd
import re

def preprocess(data):
    pattern = '\d{1,2}/\d{1,2}/\d{2,4},\s\d{1,2}:\d{2}\s-\s'
    messages = re.split(pattern, data)[1:]
    dates = re.findall(pattern, data)

    df = pd.DataFrame({'user_message': messages, "message_date": dates})
    df["message_date"] = pd.to_datetime(df["message_date"], format='%d/%m/%Y, %H:%M - ')
    df.rename(columns={"message_date": "date"}, inplace=True)

    # seperate users and messages
    users = []
    messages = []

    for message in df["user_message"]:
        entry = re.split('([\w\W]+?):\s', message)
        if entry[1:]:
            users.append(entry[1])
            messages.append(entry[2])
        else:
            users.append('Group Notification')
            messages.append(entry[0])

    df["user"] = users
    df["message"] = messages
    df.drop(columns=["user_message"], inplace=True)

    df["year"] = df["date"].dt.year
    df["month"] = df["date"].dt.month_name()
    df["day"] = df["date"].dt.day
    df["hour"] = df["date"].dt.hour
    df["minute"] = df["date"].dt.minute
    df["month_num"] = df["date"].dt.month
    df["date_only"] = df["date"].dt.date
    df["day_name"] = df["date"].dt.day_name()

    period = []
    for hour in df[["day_name", "hour"]]["hour"]:
        if hour == 23:
            period.append(str(hour) + "-" + str("00"))
        elif hour == 0:
            period.append(str("00") + "-" + str(hour + 1))
        else:
            period.append(str(hour) + "-" + str(hour + 1))
    df["period"] = period

    return df