GMB-Scraper/lib/stealth.py

"""
Stealth Mode Module
===================
Anti-detection measures for Playwright scraping.
"""

import random
from playwright_stealth import Stealth
from .logger import get_logger


# Realistic viewports (common screen resolutions)
VIEWPORTS = [
    (1920, 1080), (1366, 768), (1536, 864),
    (1440, 900), (1280, 720), (1600, 900),
    (2560, 1440), (1920, 1200), (1680, 1050),
]

# Realistic user agents (rotated to avoid fingerprinting)
USER_AGENTS = [
    "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/125.0.0.0 Safari/537.36",
    "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36",
    "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/125.0.0.0 Safari/537.36",
    "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:126.0) Gecko/20100101 Firefox/126.0",
    "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.5 Safari/605.1.15",
    "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/125.0.0.0 Safari/537.36 Edg/125.0.0.0",
]

# Timezones for Australian businesses
TIMEZONES = [
    "Australia/Perth", "Australia/Adelaide", "Australia/Brisbane",
    "Australia/Sydney", "Australia/Melbourne", "Australia/Hobart",
]

# Languages
LANGUAGES = ["en-AU", "en-US", "en-GB"]


def apply_stealth(context, page=None, randomize=False):
    """
    Apply stealth measures to Playwright context and page.
    
    Args:
        context: Playwright browser context
        page: Optional Playwright page (applies stealth to it)
        randomize: Ignored (kept for backward compat — randomization happens at context creation)
    
    Returns:
        Modified context
    """
    logger = get_logger()
    
    # Apply playwright-stealth to page
    if page:
        stealth = Stealth()
        stealth.apply_stealth_sync(page)
        logger.debug("Stealth: playwright-stealth applied")
    
    return context


def create_stealth_context(browser, headless=True, proxy=None):
    """
    Create a stealth-enabled browser context.
    
    Args:
        browser: Playwright browser instance
        headless: Whether to run headless
        proxy: Optional proxy URL
    
    Returns:
        Playwright context with stealth applied
    """
    logger = get_logger()
    
    # Base context options
    viewport = random.choice(VIEWPORTS)
    context_options = {
        "viewport": {"width": viewport[0], "height": viewport[1]},
        "user_agent": random.choice(USER_AGENTS),
        "locale": random.choice(LANGUAGES),
        "timezone_id": random.choice(TIMEZONES),
    }
    
    # Add proxy if provided
    if proxy:
        context_options["proxy"] = {"server": proxy}
        logger.info(f"Using proxy: {proxy}")
    
    # Create context
    context = browser.new_context(**context_options)
    
    # Apply stealth
    apply_stealth(context, randomize=False)
    
    return context


def human_delay(min_delay=1.0, max_delay=2.5, jitter=True):
    """
    Human-like delay with optional jitter.
    
    Args:
        min_delay: Minimum delay in seconds
        max_delay: Maximum delay in seconds
        jitter: Add random jitter
    """
    delay = random.uniform(min_delay, max_delay)
    
    if jitter:
        # Occasionally add longer pauses (like a human getting distracted)
        if random.random() < 0.1:  # 10% chance
            delay *= random.uniform(1.5, 2.5)
    
    return delay


def human_scroll_delay():
    """Delay that mimics human scrolling behavior."""
    # Most scrolls are quick, some are slow (reading)
    if random.random() < 0.7:
        return random.uniform(0.5, 1.2)
    else:
        return random.uniform(1.5, 3.0)