zendriver-stealth 0.2.0

//! Bundles individual patches into a bootstrap script driven by a [`Persona`]
//! (the surface-spoofing config) plus a [`Fingerprint`] (coherent UA / Chrome
//! identity probed at launch).
//!
//! The 9 identity patches run inside a single IIFE called with a serialized
//! fingerprint object — one `Page.addScriptToEvaluateOnNewDocument` round-trip
//! covers them. The persona-driven surface patches (canvas/audio/clientRects
//! noise, webgl/fonts/hardware value substitution, webrtc policy) are appended
//! after, each emitted only when its resolved [`Strategy`] is not `Native`.

use serde_json::json;

use crate::persona::surface::{Strategy, Surface};
use crate::persona::{FontSpec, HardwareSpec, SurfaceCfg, WebglSpec, WebrtcSpec};
use crate::{Fingerprint, Persona, Seed, UserAgentMetadata};

// --- Identity patches (run inside the fp IIFE) ---------------------------
const WEBDRIVER: &str = include_str!("patches/webdriver.js");
const PLUGINS: &str = include_str!("patches/plugins.js");
const CHROME: &str = include_str!("patches/chrome.js");
const PERMISSIONS: &str = include_str!("patches/permissions.js");
const CODECS: &str = include_str!("patches/codecs.js");
const NAVIGATOR_PROPS: &str = include_str!("patches/navigator_props.js");
const USER_AGENT_DATA: &str = include_str!("patches/user_agent_data.js");
const BROKEN_IMAGE: &str = include_str!("patches/broken_image.js");

// --- Persona surface patches (appended after the identity IIFE) ----------
//
// `webgl.js` carries BOTH the hardcoded vendor/renderer fallback block and a
// persona-driven value-substitution IIFE, so it is emitted exactly ONCE here
// (not in the identity IIFE) to avoid a duplicate block + unsubstituted
// `WEBGL_VENDOR`/`WEBGL_RENDERER` tokens. It references no `fp` fields, so
// running it at the bootstrap's top level (rather than inside the fp IIFE) is
// behavior-preserving; its top-level `const VENDOR`/`RENDERER` are script-
// scoped and the nested IIFE's `const VENDOR` is function-scoped — no
// redeclaration.
const PRNG: &str = include_str!("patches/_prng.js");
const WEBGL: &str = include_str!("patches/webgl.js");
const CANVAS: &str = include_str!("patches/canvas.js");
const AUDIO: &str = include_str!("patches/audio.js");
const CLIENT_RECTS: &str = include_str!("patches/client_rects.js");
const FONTS: &str = include_str!("patches/fonts.js");
const WEBRTC: &str = include_str!("patches/webrtc.js");
const HARDWARE: &str = include_str!("patches/hardware.js");

/// Build the bootstrap script for the spoofed profile.
///
/// `identity` supplies coherent UA-CH metadata and the *real* probed Chrome
/// version; `persona` overrides simple identity fields (platform / hardware /
/// locale) and drives the new fingerprint surfaces. Splitting the two keeps
/// the UA coherent: when the persona changes platform we rebuild the UA-CH
/// metadata against the real Chrome version instead of a stale fallback.
///
/// Order: identity IIFE first (webdriver-most-probed-first, navigator_props
/// last), then the PRNG definition, then each persona surface.
#[must_use]
pub fn bootstrap_script(persona: &Persona, identity: &Fingerprint) -> String {
    let mut out = identity_iife(persona, identity);

    let seed = persona.seed.unwrap_or_else(Seed::random).value();

    // PRNG must be defined once, before any noise/font patch that references
    // `__zdRng`. Emit it unconditionally — cheap, and harmless if every
    // surface is Native (it just defines an unused function).
    out.push('\n');
    out.push_str(PRNG);

    push_noise(
        &mut out,
        Surface::Canvas,
        persona.canvas.as_ref(),
        CANVAS,
        seed,
    );
    push_noise(
        &mut out,
        Surface::Audio,
        persona.audio.as_ref(),
        AUDIO,
        seed,
    );
    push_noise(
        &mut out,
        Surface::ClientRects,
        persona.client_rects.as_ref(),
        CLIENT_RECTS,
        seed,
    );

    push_webgl(&mut out, persona.webgl.as_ref());
    push_fonts(&mut out, persona.fonts.as_ref(), seed);
    push_hardware(&mut out, persona.hardware.as_ref());
    push_webrtc(&mut out, persona.webrtc.as_ref());

    out
}

/// Emit the 9 identity patches wrapped in `(function(fp){ ... })(fpJson)`.
/// Identity is resolved from `identity` with `persona` overrides applied,
/// preserving UA coherence (see [`bootstrap_script`]).
fn identity_iife(persona: &Persona, identity: &Fingerprint) -> String {
    let platform = persona.platform.unwrap_or(identity.platform);

    // If the persona changes the platform, rebuild UA-CH metadata coherently
    // against the REAL probed Chrome version (never a fallback) so platform +
    // platformVersion + brands all agree. Otherwise reuse the probed metadata.
    let uam = if persona.platform.is_some_and(|p| p != identity.platform) {
        UserAgentMetadata::realistic(platform, identity.chrome_major, &identity.chrome_full)
    } else {
        identity.ua_metadata.clone()
    };

    let cpu = persona.hardware_concurrency.unwrap_or(identity.cpu_count);
    let mem = persona.device_memory_gb.unwrap_or(identity.memory_gb);
    let locale = persona.locale.clone().or_else(|| identity.locale.clone());

    let fp_json = json!({
        "platformJs":      platform.js_string(),
        "chPlatform":      platform.ch_platform(),
        "platformVersion": uam.platform_version,
        "cpuCount":        cpu,
        "memoryGb":        mem,
        "languages":       locale.as_deref().map_or_else(
            || vec!["en-US".to_string(), "en".to_string()],
            |l| vec![l.to_string(), "en".to_string()],
        ),
        "architecture":    uam.architecture,
        "bitness":         uam.bitness,
        "brands":          uam.brands,
        "fullVersionList": uam.full_version_list,
    });

    format!(
        "(function(fp){{\n{WEBDRIVER}\n{PLUGINS}\n{CHROME}\n{PERMISSIONS}\n{CODECS}\n{NAVIGATOR_PROPS}\n{USER_AGENT_DATA}\n{BROKEN_IMAGE}\n}})({fp_json});",
    )
}

/// JS source for the resolved seed token of a noise surface, or `None` when
/// the surface should be omitted entirely (`Native`).
fn seed_token(strat: Strategy, seed: u64) -> Option<String> {
    match strat {
        Strategy::Native => None,
        // Constant zero seed → every farble step deterministic & uniform; the
        // `/*BLOCK*/` marker documents intent and lets tests assert on it.
        Strategy::Block => Some("0/*BLOCK*/".to_string()),
        Strategy::Seeded | Strategy::Value => Some(seed.to_string()),
        Strategy::Random => Some("(Math.random()*4294967296)>>>0".to_string()),
    }
}

/// Append a noise-surface patch (`SEED` token), respecting the resolved
/// strategy. No-op under `Native`.
fn push_noise(out: &mut String, surface: Surface, cfg: Option<&SurfaceCfg>, js: &str, seed: u64) {
    let strat = surface.resolve_strategy(cfg.and_then(|c| c.strategy));
    if let Some(tok) = seed_token(strat, seed) {
        out.push('\n');
        out.push_str(&js.replace("SEED", &tok));
    }
}

/// JSON literal for an optional string value, or JS `null` when absent.
fn json_or_null(v: Option<&String>) -> String {
    v.map_or_else(
        || "null".to_string(),
        |s| serde_json::to_string(s).unwrap_or_else(|_| "null".to_string()),
    )
}

/// Append the webgl value-substitution patch. The existing hardcoded webgl
/// block (the first half of `webgl.js`) always runs; the appended IIFE's
/// `WEBGL_VENDOR` / `WEBGL_RENDERER` args carry the persona values (or JS
/// `null` when absent / `Native`, leaving the hardcoded block in charge).
fn push_webgl(out: &mut String, spec: Option<&WebglSpec>) {
    let strat = Surface::Webgl.resolve_strategy(spec.and_then(|s| s.strategy));
    let (vendor, renderer) = match strat {
        // Under Native the persona contributes nothing — pass null so the new
        // IIFE delegates entirely to the hardcoded block (which still runs).
        Strategy::Native => ("null".to_string(), "null".to_string()),
        _ => (
            json_or_null(spec.and_then(|s| s.unmasked_vendor.as_ref())),
            json_or_null(spec.and_then(|s| s.unmasked_renderer.as_ref())),
        ),
    };
    out.push('\n');
    out.push_str(
        &WEBGL
            .replace("WEBGL_VENDOR", &vendor)
            .replace("WEBGL_RENDERER", &renderer),
    );
}

/// Append the fonts patch (`FONT_ALLOW` + `SEED`). Omitted under `Native`.
fn push_fonts(out: &mut String, spec: Option<&FontSpec>, seed: u64) {
    let strat = Surface::Fonts.resolve_strategy(spec.and_then(|s| s.strategy));
    let seed_tok = match seed_token(strat, seed) {
        None => return, // Native → omit entirely.
        Some(t) => t,
    };
    // Allow-list only meaningful when the persona supplies one AND we're not
    // blocking; under Block, hide every font (empty allow-list).
    let allow = match strat {
        Strategy::Block => "[]".to_string(),
        _ => spec.and_then(|s| s.available.as_ref()).map_or_else(
            || "null".to_string(),
            |v| serde_json::to_string(v).unwrap_or_else(|_| "null".to_string()),
        ),
    };
    out.push('\n');
    out.push_str(
        &FONTS
            .replace("FONT_ALLOW", &allow)
            .replace("SEED", &seed_tok),
    );
}

/// Append the hardware patch (`HW_BATTERY` / `HW_MEDIA_DEVICES` / `HW_VOICES`).
/// Omitted under `Native`. Each field independently `null` when unset.
fn push_hardware(out: &mut String, spec: Option<&HardwareSpec>) {
    let strat = Surface::Hardware.resolve_strategy(spec.and_then(|s| s.strategy));
    if strat == Strategy::Native {
        return;
    }
    let (battery, media, voices) = if strat == Strategy::Block {
        // Block → present a uniform, minimal hardware surface.
        ("1".to_string(), "0".to_string(), "[]".to_string())
    } else {
        let battery = spec
            .and_then(|s| s.battery_level)
            .map_or_else(|| "null".to_string(), |b| b.to_string());
        let media = spec
            .and_then(|s| s.media_devices)
            .map_or_else(|| "null".to_string(), |m| m.to_string());
        let voices = spec.and_then(|s| s.speech_voices.as_ref()).map_or_else(
            || "null".to_string(),
            |v| serde_json::to_string(v).unwrap_or_else(|_| "null".to_string()),
        );
        (battery, media, voices)
    };
    out.push('\n');
    out.push_str(
        &HARDWARE
            .replace("HW_BATTERY", &battery)
            .replace("HW_MEDIA_DEVICES", &media)
            .replace("HW_VOICES", &voices),
    );
}

/// Append the webrtc policy patch (`WEBRTC_POLICY` + `WEBRTC_FAKE_IP`).
/// The patch self-no-ops on the `"native"` policy, so we always emit it but
/// pass the strategy-derived policy string.
fn push_webrtc(out: &mut String, spec: Option<&WebrtcSpec>) {
    let strat = Surface::Webrtc.resolve_strategy(spec.and_then(|s| s.strategy));
    let policy = match strat {
        Strategy::Native => "native",
        Strategy::Value => "value",
        // Block (the policy default) + any non-meaningful fallback.
        _ => "block",
    };
    let fake_ip = json_or_null(spec.and_then(|s| s.fake_ip.as_ref()));
    out.push('\n');
    out.push_str(
        &WEBRTC
            .replace("WEBRTC_POLICY", &format!("\"{policy}\""))
            .replace("WEBRTC_FAKE_IP", &fake_ip),
    );
}

#[cfg(test)]
#[allow(clippy::panic, clippy::unwrap_used)]
mod tests {
    use super::*;
    use crate::persona::surface::Strategy;
    use crate::{Platform, UserAgentMetadata};

    fn mock_identity() -> Fingerprint {
        Fingerprint {
            platform: Platform::MacIntel,
            chrome_major: 120,
            chrome_full: "120.0.6099.234".into(),
            cpu_count: 10,
            memory_gb: 8,
            ua_string: String::new(),
            ua_metadata: UserAgentMetadata::realistic(Platform::MacIntel, 120, "120.0.6099.234"),
            timezone: None,
            locale: Some("en-US".into()),
        }
    }

    // --- Migrated identity tests (the original three) --------------------

    #[test]
    fn bootstrap_includes_all_nine_patches() {
        let s = bootstrap_script(&Persona::default(), &mock_identity());
        assert!(s.contains("webdriver"), "webdriver patch missing");
        assert!(s.contains("PluginArray"), "plugins patch missing");
        assert!(s.contains("window.chrome"), "chrome patch missing");
        assert!(
            s.contains("UNMASKED_VENDOR_WEBGL") || s.contains("37445"),
            "webgl patch missing"
        );
        assert!(
            s.contains("Notification.permission"),
            "permissions patch missing"
        );
        assert!(s.contains("canPlayType"), "codecs patch missing");
        assert!(
            s.contains("hardwareConcurrency"),
            "navigator_props patch missing"
        );
        assert!(s.contains("userAgentData"), "user_agent_data patch missing");
        assert!(s.contains("naturalWidth"), "broken_image patch missing");
    }

    #[test]
    fn bootstrap_is_an_iife_taking_fp() {
        let s = bootstrap_script(&Persona::default(), &mock_identity());
        assert!(s.starts_with("(function(fp){"));
        assert!(s.contains("})({"), "fp arg JSON should follow");
    }

    #[test]
    fn bootstrap_substitutes_platform_js_string() {
        let s = bootstrap_script(&Persona::default(), &mock_identity());
        assert!(s.contains("\"MacIntel\""));
    }

    // --- Identity coherence ---------------------------------------------

    #[test]
    fn persona_platform_override_rebuilds_uam_with_real_chrome_version() {
        // identity is mac/chrome120; persona overrides platform to Win32.
        // The rebuilt UA-CH must use the REAL chrome version (120) and the
        // Win32 platformVersion (15.0.0), not a fallback.
        let persona = Persona {
            platform: Some(Platform::Win32),
            ..Persona::default()
        };
        let s = bootstrap_script(&persona, &mock_identity());
        assert!(s.contains("\"Win32\""), "platformJs should be Win32");
        assert!(
            s.contains("15.0.0"),
            "Win32 platformVersion should be present"
        );
        // chrome 120 brands carried through from the real identity.
        assert!(s.contains("\"120\""), "real chrome major should survive");
    }

    #[test]
    fn persona_overrides_simple_identity_fields() {
        let persona = Persona {
            hardware_concurrency: Some(4),
            device_memory_gb: Some(16),
            locale: Some("fr-FR".into()),
            ..Persona::default()
        };
        let s = bootstrap_script(&persona, &mock_identity());
        assert!(s.contains("\"cpuCount\":4"), "cpu override missing");
        // deviceMemory is rendered into the fp json untouched here (the JS
        // clamps); persona value should appear.
        assert!(s.contains("\"memoryGb\":16"), "memory override missing");
        assert!(s.contains("fr-FR"), "locale override missing");
    }

    // --- Surface strategy emission (new) --------------------------------

    #[test]
    fn native_strategy_omits_surface_patch() {
        let p = Persona {
            canvas: Some(SurfaceCfg {
                strategy: Some(Strategy::Native),
            }),
            seed: Some(Seed::from_u64(1)),
            ..Persona::default()
        };
        let script = bootstrap_script(&p, &mock_identity());
        assert!(
            !script.contains("origGetImageData"),
            "Native canvas → no farble hook"
        );
    }

    #[test]
    fn block_strategy_emits_constant_canvas() {
        let p = Persona {
            canvas: Some(SurfaceCfg {
                strategy: Some(Strategy::Block),
            }),
            ..Persona::default()
        };
        let script = bootstrap_script(&p, &mock_identity());
        // canvas patch IS emitted (hook present) but seeded with the BLOCK
        // marker rather than a live seed.
        assert!(
            script.contains("origGetImageData"),
            "Block canvas still hooks getImageData"
        );
        assert!(script.contains("BLOCK"), "Block canvas marker present");
    }

    #[test]
    fn seeded_canvas_templates_seed() {
        let p = Persona {
            canvas: Some(SurfaceCfg {
                strategy: Some(Strategy::Seeded),
            }),
            seed: Some(Seed::from_u64(123)),
            ..Persona::default()
        };
        let script = bootstrap_script(&p, &mock_identity());
        assert!(
            script.contains("origGetImageData"),
            "canvas farble must hook getImageData"
        );
        // The seed `123` is substituted as the IIFE arg: `})(123);`
        assert!(
            script.contains("})(123)"),
            "seed value must be templated in"
        );
    }

    #[test]
    fn random_canvas_uses_math_random_seed() {
        let p = Persona {
            canvas: Some(SurfaceCfg {
                strategy: Some(Strategy::Random),
            }),
            ..Persona::default()
        };
        let script = bootstrap_script(&p, &mock_identity());
        assert!(
            script.contains("Math.random()*4294967296"),
            "Random canvas re-seeds per page"
        );
    }

    #[test]
    fn webgl_value_substitutes_persona_renderer() {
        let p = Persona {
            webgl: Some(WebglSpec {
                strategy: Some(Strategy::Value),
                unmasked_vendor: Some("Google Inc. (NVIDIA)".into()),
                unmasked_renderer: Some("ANGLE (NVIDIA GeForce RTX 4090)".into()),
            }),
            ..Persona::default()
        };
        let script = bootstrap_script(&p, &mock_identity());
        assert!(
            script.contains("ANGLE (NVIDIA GeForce RTX 4090)"),
            "persona renderer must be substituted into the webgl IIFE"
        );
        assert!(
            script.contains("Google Inc. (NVIDIA)"),
            "persona vendor must be substituted into the webgl IIFE"
        );
    }

    #[test]
    fn webgl_native_passes_null_and_keeps_hardcoded_block() {
        // No webgl spec → Native resolution → IIFE args null, but the
        // hardcoded fallback block (37445/37446) still present.
        let script = bootstrap_script(&Persona::default(), &mock_identity());
        assert!(
            s_has_webgl_iife_null(&script),
            "webgl IIFE args should be null"
        );
        assert!(
            script.contains("37445"),
            "hardcoded webgl fallback block must remain"
        );
    }

    fn s_has_webgl_iife_null(s: &str) -> bool {
        // The appended webgl IIFE ends with its args; null both => `})(null, null);`
        s.contains("})(null, null);")
    }

    #[test]
    fn fonts_native_omits_measuretext_hook() {
        let p = Persona {
            fonts: Some(FontSpec {
                strategy: Some(Strategy::Native),
                available: None,
            }),
            ..Persona::default()
        };
        let script = bootstrap_script(&p, &mock_identity());
        assert!(
            !script.contains("measureText"),
            "Native fonts → no measureText hook"
        );
    }

    #[test]
    fn fonts_value_substitutes_allow_list() {
        let p = Persona {
            fonts: Some(FontSpec {
                strategy: Some(Strategy::Value),
                available: Some(vec!["Arial".into(), "Helvetica".into()]),
            }),
            seed: Some(Seed::from_u64(7)),
            ..Persona::default()
        };
        let script = bootstrap_script(&p, &mock_identity());
        assert!(script.contains("measureText"), "fonts patch emitted");
        assert!(
            script.contains("[\"Arial\",\"Helvetica\"]"),
            "allow-list substituted"
        );
    }

    #[test]
    fn webrtc_value_substitutes_policy_and_ip() {
        let p = Persona {
            webrtc: Some(WebrtcSpec {
                strategy: Some(Strategy::Value),
                fake_ip: Some("203.0.113.7".into()),
            }),
            ..Persona::default()
        };
        let script = bootstrap_script(&p, &mock_identity());
        assert!(
            script.contains("})(\"value\", \"203.0.113.7\");"),
            "webrtc value policy + fake ip substituted"
        );
    }

    #[test]
    fn webrtc_default_is_block_policy() {
        let script = bootstrap_script(&Persona::default(), &mock_identity());
        assert!(
            script.contains("})(\"block\", null);"),
            "default webrtc policy is block with no fake ip"
        );
    }

    #[test]
    fn hardware_native_omits_patch() {
        let p = Persona {
            hardware: Some(HardwareSpec {
                strategy: Some(Strategy::Native),
                ..HardwareSpec::default()
            }),
            ..Persona::default()
        };
        let script = bootstrap_script(&p, &mock_identity());
        assert!(
            !script.contains("getBattery"),
            "Native hardware → no getBattery hook"
        );
    }

    #[test]
    fn hardware_value_substitutes_specs() {
        let p = Persona {
            hardware: Some(HardwareSpec {
                strategy: Some(Strategy::Value),
                battery_level: Some(0.5),
                media_devices: Some(3),
                speech_voices: Some(vec!["Daniel".into()]),
            }),
            ..Persona::default()
        };
        let script = bootstrap_script(&p, &mock_identity());
        assert!(script.contains("getBattery"), "hardware patch emitted");
        assert!(
            script.contains("})(0.5, 3, [\"Daniel\"]);"),
            "hardware specs substituted"
        );
    }

    #[test]
    fn prng_defined_once() {
        let p = Persona {
            canvas: Some(SurfaceCfg {
                strategy: Some(Strategy::Seeded),
            }),
            audio: Some(SurfaceCfg {
                strategy: Some(Strategy::Seeded),
            }),
            ..Persona::default()
        };
        let script = bootstrap_script(&p, &mock_identity());
        assert_eq!(
            script.matches("function __zdRng(").count(),
            1,
            "PRNG defined exactly once even with multiple noise surfaces"
        );
    }

    #[test]
    fn no_unsubstituted_tokens_remain() {
        // Exercise every surface so all token-bearing patches are emitted.
        let p = Persona {
            canvas: Some(SurfaceCfg {
                strategy: Some(Strategy::Seeded),
            }),
            audio: Some(SurfaceCfg {
                strategy: Some(Strategy::Random),
            }),
            client_rects: Some(SurfaceCfg {
                strategy: Some(Strategy::Block),
            }),
            webgl: Some(WebglSpec {
                strategy: Some(Strategy::Value),
                unmasked_vendor: Some("V".into()),
                unmasked_renderer: Some("R".into()),
            }),
            fonts: Some(FontSpec {
                strategy: Some(Strategy::Value),
                available: Some(vec!["Arial".into()]),
            }),
            webrtc: Some(WebrtcSpec {
                strategy: Some(Strategy::Value),
                fake_ip: Some("1.2.3.4".into()),
            }),
            hardware: Some(HardwareSpec {
                strategy: Some(Strategy::Value),
                battery_level: Some(0.9),
                media_devices: Some(2),
                speech_voices: Some(vec!["A".into()]),
            }),
            seed: Some(Seed::from_u64(9)),
            ..Persona::default()
        };
        let script = bootstrap_script(&p, &mock_identity());
        for tok in [
            "SEED",
            "WEBGL_VENDOR",
            "WEBGL_RENDERER",
            "FONT_ALLOW",
            "WEBRTC_POLICY",
            "WEBRTC_FAKE_IP",
            "HW_BATTERY",
            "HW_MEDIA_DEVICES",
            "HW_VOICES",
        ] {
            assert!(
                !script.contains(tok),
                "unsubstituted token `{tok}` left in bootstrap"
            );
        }
    }
}