src/core/stealth.py

"""Comprehensive anti-detection (stealth) scripts for Playwright browser contexts.

This module centralises all anti-fingerprinting init scripts used by the
various captcha solvers.  Every solver should import from here instead of
maintaining its own copy.

Key techniques:
  - Remove / mask navigator.webdriver
  - Realistic navigator.plugins (not a plain array)
  - Full window.chrome shim
  - Permissions API override
  - navigator.connection simulation
  - Console.debug masking (reCAPTCHA detection vector)
  - getBoundingClientRect consistency patch
  - iframe contentWindow protection
"""

from __future__ import annotations

# ── Core stealth script ──────────────────────────────────────────────

STEALTH_JS = """
// ── 1. navigator.webdriver ─────────────────────────────────────────
// Delete the property from the prototype so `webdriver in navigator` is false,
// not just returning undefined from a getter.
try {
    Object.defineProperty(navigator, 'webdriver', {
        get: () => undefined,
        configurable: true
    });
    delete Object.getPrototypeOf(navigator).__proto__.webdriver;
} catch (_) {}

// ── 2. navigator.plugins — realistic mock ───────────────────────────
// Google's bot detection checks that plugins is a PluginArray, not a plain
// array.  We construct a minimal but plausible PluginArray-like object.
try {
    const _makePlugin = (name, filename, description, mimes) => {
        const m = mimes.map(t => Object.create(MimeType.prototype, {
            type:        { value: t.type,        enumerable: true },
            suffixes:    { value: t.suffixes,    enumerable: true },
            description: { value: t.description, enumerable: true }
        }));
        const p = Object.create(Plugin.prototype, {
            name:        { value: name,        enumerable: true },
            filename:    { value: filename,    enumerable: true },
            description: { value: description, enumerable: true },
            length:      { value: m.length,    enumerable: true }
        });
        m.forEach((mime, i) => { p[i] = mime; });
        return p;
    };
    const _plugins = [
        _makePlugin('PDF Viewer', 'internal-pdf-viewer', 'Portable Document Format', [
            { type: 'application/pdf', suffixes: 'pdf', description: '' }
        ]),
        _makePlugin('Chrome PDF Viewer', 'internal-pdf-viewer', 'Portable Document Format', [
            { type: 'application/pdf', suffixes: 'pdf', description: '' }
        ]),
        _makePlugin('Chromium PDF Plugin', 'internal-pdf-viewer', 'Portable Document Format', [
            { type: 'application/pdf', suffixes: 'pdf', description: '' }
        ]),
    ];
    const pluginArray = Object.create(PluginArray.prototype);
    _plugins.forEach((p, i) => {
        Object.defineProperty(pluginArray, i, { value: p, enumerable: true });
        Object.defineProperty(pluginArray, p.name, { value: p, enumerable: true });
    });
    Object.defineProperty(pluginArray, 'length', { value: _plugins.length, enumerable: true });
    Object.defineProperty(navigator, 'plugins', {
        get: () => pluginArray,
        configurable: true
    });
} catch (_) {}

// ── 3. window.chrome shim ───────────────────────────────────────────
// A real Chrome browser always exposes a `chrome` global with several
// well-known sub-properties.
try {
    if (!window.chrome) {
        window.chrome = {};
    }
    if (!window.chrome.runtime) {
        window.chrome.runtime = {
            OnInstalledReason: {
                CHROME_UPDATE: 'chrome_update',
                INSTALL: 'install',
                SHARED_MODULE_UPDATE: 'shared_module_update',
                UPDATE: 'update'
            },
            OnRestartRequiredReason: {
                APP_UPDATE: 'app_update',
                OS_UPDATE: 'os_update',
                PERIODIC: 'periodic'
            },
            PlatformArch: {
                ARM: 'arm',
                ARM64: 'arm64',
                MIPS: 'mips',
                MIPS64: 'mips64',
                X86_32: 'x86-32',
                X86_64: 'x86-64'
            },
            PlatformNaclArch: {
                ARM: 'arm',
                MIPS: 'mips',
                MIPS64: 'mips64',
                X86_32: 'x86-32',
                X86_64: 'x86-64'
            },
            PlatformOs: {
                ANDROID: 'android',
                CROS: 'cros',
                LINUX: 'linux',
                MAC: 'mac',
                OPENBSD: 'openbsd',
                WIN: 'win'
            },
            RequestUpdateCheckStatus: {
                NO_UPDATE: 'no_update',
                THROTTLED: 'throttled',
                UPDATE_AVAILABLE: 'update_available'
            },
            connect: function() {},
            sendMessage: function() {}
        };
    }
    if (!window.chrome.csi) {
        window.chrome.csi = function() {
            return {
                onloadT: Date.now(),
                startE: Date.now(),
                pageT: Math.random() * 500 + 100,
                tran: 15
            };
        };
    }
    if (!window.chrome.loadTimes) {
        window.chrome.loadTimes = function() {
            const now = Date.now() / 1000;
            return {
                commitLoadTime: now,
                connectionInfo: 'h2',
                finishDocumentLoadTime: now + 0.1,
                finishLoadTime: now + 0.2,
                firstPaintAfterLoadTime: now + 0.3,
                firstPaintTime: now + 0.05,
                navigationType: 'Other',
                npnNegotiatedProtocol: 'h2',
                requestTime: now - 0.5,
                startLoadTime: now - 0.4,
                wasAlternateProtocolAvailable: false,
                wasFetchedViaSpdy: true,
                wasNpnNegotiated: true
            };
        };
    }
} catch (_) {}

// ── 4. navigator.languages ──────────────────────────────────────────
try {
    Object.defineProperty(navigator, 'languages', {
        get: () => ['en-US', 'en'],
        configurable: true
    });
} catch (_) {}

// ── 5. Permissions API override ─────────────────────────────────────
// reCAPTCHA calls navigator.permissions.query({name:'notifications'}) and
// expects a typical result.  Headless Chromium returns a different state.
try {
    const _origQuery = window.Permissions.prototype.query;
    window.Permissions.prototype.query = function(parameters) {
        if (parameters.name === 'notifications') {
            return Promise.resolve({
                state: Notification.permission === 'denied' ? 'denied' : 'prompt',
                onchange: null
            });
        }
        return _origQuery.call(this, parameters);
    };
} catch (_) {}

// ── 6. navigator.connection ──────────────────────────────────────────
try {
    if (!navigator.connection) {
        Object.defineProperty(navigator, 'connection', {
            get: () => ({
                effectiveType: '4g',
                rtt: 50,
                downlink: 10,
                saveData: false,
                onchange: null,
                addEventListener: function() {},
                removeEventListener: function() {}
            }),
            configurable: true
        });
    }
} catch (_) {}

// ── 7. Console.debug masking ────────────────────────────────────────
// Some captcha scripts inject a debug probe via console.debug.
try {
    const _origDebug = console.debug;
    console.debug = function() {
        if (arguments.length && typeof arguments[0] === 'string'
            && arguments[0].includes('Captcha')) {
            return;
        }
        return _origDebug.apply(console, arguments);
    };
} catch (_) {}

// ── 8. getBoundingClientRect consistency ─────────────────────────────
// Headless Chromium's element rects can subtly differ; ensure getClientRects
// returns results when getBoundingClientRect does.
try {
    const _origGetClientRects = Element.prototype.getClientRects;
    Element.prototype.getClientRects = function() {
        const rects = _origGetClientRects.call(this);
        if (rects.length === 0) {
            const br = this.getBoundingClientRect();
            if (br.width > 0 && br.height > 0) {
                return [br];
            }
        }
        return rects;
    };
} catch (_) {}

// ── 9. WebGL vendor / renderer override ─────────────────────────────
// Some detections read the unmasked WebGL renderer to spot headless.
try {
    const _origGetParam = WebGLRenderingContext.prototype.getParameter;
    WebGLRenderingContext.prototype.getParameter = function(param) {
        if (param === 37445) return 'Intel Inc.';  // UNMASKED_VENDOR_WEBGL
        if (param === 37446) return 'Intel Iris OpenGL Engine';  // UNMASKED_RENDERER_WEBGL
        return _origGetParam.call(this, param);
    };
    if (typeof WebGL2RenderingContext !== 'undefined') {
        const _origGetParam2 = WebGL2RenderingContext.prototype.getParameter;
        WebGL2RenderingContext.prototype.getParameter = function(param) {
            if (param === 37445) return 'Intel Inc.';
            if (param === 37446) return 'Intel Iris OpenGL Engine';
            return _origGetParam2.call(this, param);
        };
    }
} catch (_) {}

// ── 10. iframe contentWindow protection ─────────────────────────────
// Ensure cross-origin iframes expose a .contentWindow (headless sometimes
// returns null).
try {
    const _origDesc = Object.getOwnPropertyDescriptor(HTMLIFrameElement.prototype, 'contentWindow');
    if (!_origDesc || !_origDesc.get) {
        Object.defineProperty(HTMLIFrameElement.prototype, 'contentWindow', {
            get: function() {
                return this._contentWindow || window;
            },
            configurable: true
        });
    }
} catch (_) {}
"""

# ── Browser launch arguments ─────────────────────────────────────────

STEALTH_LAUNCH_ARGS = [
    "--disable-blink-features=AutomationControlled",
    "--no-sandbox",
    "--disable-dev-shm-usage",
    "--disable-gpu",
    # Additional anti-detection flags
    "--disable-infobars",
    "--window-size=1920,1080",
    "--disable-extensions",
    "--disable-component-extensions-with-background-pages",
    "--disable-default-apps",
    "--disable-background-timer-throttling",
    "--disable-backgrounding-occluded-windows",
    "--disable-renderer-backgrounding",
    "--disable-background-networking",
    "--disable-breakpad",
    "--disable-component-update",
    "--disable-domain-reliability",
    "--disable-sync",
    "--disable-features=TranslateUI",
    "--no-first-run",
    "--no-default-browser-check",
]

# ── Realistic User-Agent strings (rotated per context) ──────────────

USER_AGENTS = [
    (
        "Mozilla/5.0 (Windows NT 10.0; Win64; x64) "
        "AppleWebKit/537.36 (KHTML, like Gecko) "
        "Chrome/131.0.0.0 Safari/537.36"
    ),
    (
        "Mozilla/5.0 (Windows NT 10.0; Win64; x64) "
        "AppleWebKit/537.36 (KHTML, like Gecko) "
        "Chrome/130.0.0.0 Safari/537.36"
    ),
    (
        "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) "
        "AppleWebKit/537.36 (KHTML, like Gecko) "
        "Chrome/131.0.0.0 Safari/537.36"
    ),
    (
        "Mozilla/5.0 (X11; Linux x86_64) "
        "AppleWebKit/537.36 (KHTML, like Gecko) "
        "Chrome/131.0.0.0 Safari/537.36"
    ),
]