#!/usr/bin/env python3
# Description: Monitor a website for changes.
# Usage: python3 diff-web.py --domain example.com --time 300 --email user@example.com
# Author: Justin Oros
# Source: https://github.com/JustinOros

#!/usr/bin/env python3
# Description: A script to monitor a webpage for text changes and log meaningful updates.
# Usage: python3 diff-web.py --domain example.com --time 300 --email user@example.com

import argparse
import hashlib
import os
import re
import sys
import time
from datetime import datetime
from getpass import getpass
from urllib.parse import urlparse

import requests
from bs4 import BeautifulSoup

def clean_text(text):
    junk_phrases = [
        r'\bMenu\b', r'\bClose\b', r'\bSign ?In\b', r'\bSign ?Out\b',
        r'\bLogin\b', r'\bLogout\b', r'\bBack\b', r'\bNext\b', r'\bMore\b',
        r'\bSearch\b', r'\bCart\b', r'\bSettings\b', r'\bHelp\b',
        r'\bContact\b', r'\bLanguage\b', r'\bProfile\b', r'\bAccount\b',
        r'\bSupport\b', r'\bUS\b', r'\bEN\b', r'\bFR\b', r'\bDE\b',
        r'\bJP\b', r'\bES\b', r'\bIT\b', r'\bCN\b', r'\b≡\b', r'\b×\b'
    ]

    text = re.sub(r'\b(?:US|EN|FR|DE|JP|ES|IT|CN)\b(\s*chevron_right\s*)+', '', text, flags=re.IGNORECASE)
    text = re.sub(r'(chevron_right\s*){2,}', '', text, flags=re.IGNORECASE)
    text = re.sub(r'\bchevron_right\b', '', text, flags=re.IGNORECASE)

    for pattern in junk_phrases:
        text = re.sub(pattern, '', text, flags=re.IGNORECASE)

    text = re.sub(r'\s+', ' ', text)
    return text.strip()

def fetch_content(url):
    response = requests.get(url, timeout=10)
    response.raise_for_status()
    soup = BeautifulSoup(response.text, 'html.parser')

    for tag in soup(["script", "style", "noscript", "iframe", "svg", "canvas", "header", "footer", "nav", "form", "button"]):
        tag.decompose()

    keep_tags = ['h1', 'h2', 'h3', 'h4', 'p', 'li', 'article', 'section', 'span', 'div']
    for tag in soup.find_all(True):
        if tag.name not in keep_tags:
            tag.decompose()

    raw_text = soup.get_text(separator=' ', strip=True)
    return clean_text(raw_text)

def hash_content(content):
    return hashlib.sha256(content.encode('utf-8')).hexdigest()

def save_log(domain, content):
    now = datetime.now()
    timestamp = now.strftime("%Y%m%d.%H%M%S")
    domain_name = domain.replace("https://", "").replace("http://", "").split("/")[0]
    filename = f"{domain_name}.{timestamp}.log"
    with open(filename, "w", encoding="utf-8") as f:
        f.write(content)
    print(f"[+] Change detected. Log saved to: {os.path.abspath(filename)}")

def prompt_credentials(args):
    try:
        if args.email is not None:
            if not args.email:
                args.email = input("Enter your email: ").strip()
            if not args.password:
                args.password = getpass("Enter your password: ")
    except KeyboardInterrupt:
        print("\n[!] Input canceled by user. Exiting.")
        sys.exit(0)
    return args

def main():
    parser = argparse.ArgumentParser(description="Monitor a webpage for changes.")
    parser.add_argument("positional_domain", nargs="?", help="Domain to monitor (e.g., example.com)")
    parser.add_argument("-d", "--domain", type=str, help="Domain to monitor (e.g., example.com)")
    parser.add_argument("--time", type=int, default=300, help="Polling interval in seconds (default: 300)")
    parser.add_argument("-e", "--email", nargs="?", const="", help="Your email address (optional prompt)")
    parser.add_argument("-p", "--password", type=str, help="Your password (discouraged: will show in history)")

    args = parser.parse_args()
    args = prompt_credentials(args)

    domain = args.domain or args.positional_domain
    if not domain:
        print("Error: No domain provided. Use -d/--domain or provide it as a positional argument.")
        sys.exit(1)

    url = domain if domain.startswith("http") else "https://" + domain
    print(f"[+] Monitoring: {url} every {args.time} seconds")
    if args.email:
        print(f"[+] Email: {args.email}")

    previous_hash = None

    while True:
        try:
            content = fetch_content(url)
            current_hash = hash_content(content)

            if previous_hash and current_hash != previous_hash:
                save_log(url, content)
            else:
                print(f"[{datetime.now().strftime('%H:%M:%S')}] No change.")

            previous_hash = current_hash
        except Exception as e:
            print(f"[!] Error: {e}")

        try:
            time.sleep(args.time)
        except KeyboardInterrupt:
            print("\n[!] Monitoring stopped by user. Goodbye!")
            sys.exit(0)

if __name__ == "__main__":
    try:
        main()
    except KeyboardInterrupt:
        print("\n[!] Monitoring stopped by user. Goodbye!")
        sys.exit(0)