bao_browser/

cdp_handler.rs

// @trace REQ-CDP-001  REQ-CDP-003: Bridge handler — routes BridgeCommand to servo WebView operations
// Runs on the main thread during the event loop to process CDP commands.

use bao_cdp::servo_bridge::{BridgeCommand, BridgeResponse};
use base64::Engine;
use serde_json::Value;
use servo::{CookieSource, StorageType};
use std::collections::HashSet;

use crate::config::PageConfig;
use crate::delegate::{
    ServiceWorkerHandle, ServiceWorkerRegistrationId, ServiceWorkerRegistrationState,
};
use crate::error::BrowserError;
use crate::page::PageHandle;
use crate::page_pool::PagePool;
use crate::screenshot::ScreenshotFormat;

/// Process a single bridge command by dispatching to the appropriate page in the pool.
pub fn handle_bridge_command(cmd: BridgeCommand, pool: &PagePool) -> BridgeResponse {
    let result = match cmd {
        // Multi-target management commands — operate on the pool, not a specific page
        BridgeCommand::CreateTarget { url } => cmd_create_target(pool, &url),
        BridgeCommand::ListTargets => cmd_list_targets(pool),

        // All other commands require a target_id to look up the page
        BridgeCommand::Navigate { target_id, url } => {
            with_page(pool, &target_id, |page| cmd_navigate(page, &url))
        }
        BridgeCommand::EvaluateJs {
            target_id,
            expression,
            return_by_value,
        } => with_page(pool, &target_id, |page| {
            cmd_evaluate(page, &expression, return_by_value)
        }),
        BridgeCommand::TakeScreenshot {
            target_id,
            format,
            quality: _,
        } => with_page(pool, &target_id, |page| cmd_screenshot(page, &format)),
        BridgeCommand::GetTitle { target_id } => with_page(pool, &target_id, cmd_get_title),
        BridgeCommand::GetUrl { target_id } => with_page(pool, &target_id, cmd_get_url),
        BridgeCommand::GetDocument { target_id } => with_page(pool, &target_id, cmd_get_document),
        BridgeCommand::QuerySelector {
            target_id,
            selector,
        } => with_page(pool, &target_id, |page| cmd_query_selector(page, &selector)),
        BridgeCommand::QuerySelectorAll {
            target_id,
            selector,
        } => with_page(pool, &target_id, |page| {
            cmd_query_selector_all(page, &selector)
        }),
        BridgeCommand::GetOuterHtml { target_id, .. } => {
            with_page(pool, &target_id, cmd_get_outer_html)
        }
        BridgeCommand::SetAttributeValue {
            target_id,
            node_id: _,
            name,
            value,
        } => with_page(pool, &target_id, |page| {
            cmd_set_attribute(page, &name, &value)
        }),
        BridgeCommand::DispatchMouseEvent {
            target_id,
            event_type,
            x,
            y,
            button,
            click_count,
        } => with_page(pool, &target_id, |page| {
            cmd_mouse_event(page, &event_type, x, y, button, click_count)
        }),
        BridgeCommand::DispatchKeyEvent {
            target_id,
            event_type,
            key,
            code,
            text,
        } => with_page(pool, &target_id, |page| {
            cmd_key_event(page, &event_type, &key, &code, text.as_deref())
        }),
        BridgeCommand::InsertText { target_id, text } => {
            with_page(pool, &target_id, |page| cmd_insert_text(page, &text))
        }
        BridgeCommand::SetViewport {
            target_id,
            width,
            height,
            device_scale_factor: _,
        } => with_page(pool, &target_id, |page| {
            cmd_set_viewport(page, width, height)
        }),
        BridgeCommand::SetUserAgent {
            target_id,
            user_agent,
        } => with_page(pool, &target_id, |page| {
            cmd_set_user_agent(page, &user_agent)
        }),
        BridgeCommand::AddScriptToEvaluateOnNewDocument { target_id, source } => {
            with_page(pool, &target_id, |page| cmd_add_script(page, &source))
        }
        BridgeCommand::Reload {
            target_id,
            ignore_cache: _,
        } => with_page(pool, &target_id, cmd_reload),
        BridgeCommand::GoBack { target_id } => with_page(pool, &target_id, cmd_go_back),
        BridgeCommand::GoForward { target_id } => with_page(pool, &target_id, cmd_go_forward),
        // servo WebView exposes no stop-loading API (load cancellation is not
        // part of the embedding surface) — explicit error, never a fake ok.
        BridgeCommand::StopLoading { .. } => Err(
            "Page.stopLoading not supported: servo WebView has no stop-loading API".into(),
        ),
        BridgeCommand::ClosePage { target_id } => {
            let id = parse_target_id(&target_id);
            match id {
                Some(id) => {
                    let _ = pool.close_page(id);
                    Ok(serde_json::json!({}))
                }
                None => Err(format!("invalid target_id: {target_id}")),
            }
        }
        // Cookie commands — bridge to servo SiteDataManager
        BridgeCommand::GetCookies { target_id, urls } => {
            with_page(pool, &target_id, |page| cmd_get_cookies(page, &urls))
        }
        BridgeCommand::GetAllCookies { target_id } => {
            with_page(pool, &target_id, cmd_get_all_cookies)
        }
        BridgeCommand::DeleteCookie {
            target_id,
            name,
            url,
        } => with_page(pool, &target_id, |page| {
            cmd_delete_cookie(page, &name, url.as_deref())
        }),
        BridgeCommand::SetCookie {
            target_id,
            name,
            value,
            url,
            domain,
        } => with_page(pool, &target_id, |page| {
            cmd_set_cookie(page, &name, &value, url.as_deref(), domain.as_deref())
        }),
        // servo does not store network response bodies for embedder access —
        // explicit error instead of an empty-body fake success.
        BridgeCommand::GetResponseBody { .. } => Err(
            "Network.getResponseBody not supported: servo does not expose stored response bodies to the embedder".into(),
        ),

        // Network domain — cache/cookies clearing, enable/disable
        BridgeCommand::NetworkEnable { .. } => ok_empty(),
        BridgeCommand::NetworkDisable { .. } => ok_empty(),
        BridgeCommand::NetworkSetCacheDisabled {
            target_id,
            cache_disabled,
        } => with_page(pool, &target_id, |page| {
            cmd_network_set_cache_disabled(page, cache_disabled)
        }),
        // servo WebView has no per-target extra-headers injection API —
        // explicit error instead of silently dropping the headers.
        BridgeCommand::NetworkSetExtraHTTPHeaders { .. } => Err(
            "Network.setExtraHTTPHeaders not supported: servo WebView has no extra-headers injection API".into(),
        ),
        BridgeCommand::NetworkClearBrowserCache { target_id } => {
            with_page(pool, &target_id, cmd_network_clear_browser_cache)
        }
        BridgeCommand::NetworkClearBrowserCookies { target_id } => {
            with_page(pool, &target_id, cmd_network_clear_browser_cookies)
        }

        // Storage domain — origin-scoped storage queries and clearing
        BridgeCommand::StorageGetStorageItemsForOrigin {
            target_id,
            origin,
            storage_type,
        } => with_page(pool, &target_id, |page| {
            cmd_storage_get_items(page, origin, storage_type)
        }),
        BridgeCommand::StorageClearDataForOrigin {
            target_id,
            origin,
            storage_type,
        } => with_page(pool, &target_id, |page| {
            cmd_storage_clear_data(page, origin, storage_type)
        }),

        // Security domain — enable/disable/certificate override
        BridgeCommand::SecurityEnable { .. } => ok_empty(),
        BridgeCommand::SecurityDisable { .. } => ok_empty(),
        // Certificate-error override is startup-only (BaoConfig.ignore_certificate_errors
        // → servo opts, read by the connector at init). No runtime per-target
        // override face exists — explicit error, never a silent no-op ok.
        BridgeCommand::SecuritySetOverrideCertificateErrors { .. } => Err(
            "Security.setOverrideCertificateErrors not supported at runtime: certificate-error override is startup-only (BaoConfig.ignore_certificate_errors)".into(),
        ),

        // Debugger domain — route through EvaluateJs to servo's debugger.js
        // These BridgeCommands are typed (no JS string injection from CDP layer).
        // cdp_handler translates them into servo debugger.js control messages.
        // @trace BUG-CDP-006 [domain:Debugger]: current path is EvaluateJs →
        // servo debugger.js. A future enhancement is direct routing via
        // DevtoolScriptControlMsg once servo's devtools channel is exposed to Bao.
        BridgeCommand::DebuggerEnable { target_id } => {
            with_page(pool, &target_id, |page| cmd_debugger_enable(page))
        }
        BridgeCommand::DebuggerDisable { target_id } => {
            with_page(pool, &target_id, |page| cmd_debugger_disable(page))
        }
        BridgeCommand::DebuggerSetBreakpoint {
            target_id,
            url,
            url_regex,
            line,
            column,
        } => with_page(pool, &target_id, |page| {
            cmd_debugger_set_breakpoint(page, url.as_deref(), url_regex.as_deref(), line, column)
        }),
        BridgeCommand::DebuggerRemoveBreakpoint {
            target_id,
            breakpoint_id,
        } => with_page(pool, &target_id, |page| {
            cmd_debugger_remove_breakpoint(page, &breakpoint_id)
        }),
        BridgeCommand::DebuggerInterrupt { target_id } => {
            with_page(pool, &target_id, |page| cmd_debugger_interrupt(page))
        }
        BridgeCommand::DebuggerResume {
            target_id,
            step_type,
        } => with_page(pool, &target_id, |page| {
            cmd_debugger_resume(page, step_type.as_deref())
        }),
        BridgeCommand::DebuggerListFrames { target_id } => {
            with_page(pool, &target_id, |page| cmd_debugger_list_frames(page))
        }
        BridgeCommand::DebuggerGetEnvironment { target_id, .. } => {
            with_page(pool, &target_id, |page| cmd_debugger_get_environment(page))
        }
        BridgeCommand::DebuggerEval {
            target_id,
            expression,
            frame_actor_id: _,
        } => with_page(pool, &target_id, |page| {
            cmd_evaluate(page, &expression, true)
        }),
        BridgeCommand::DebuggerGetPossibleBreakpoints {
            target_id,
            start_script_id,
        } => with_page(pool, &target_id, |page| {
            cmd_debugger_get_possible_breakpoints(page, &start_script_id)
        }),
        BridgeCommand::DebuggerGetScriptSource {
            target_id,
            script_id,
        } => with_page(pool, &target_id, |page| {
            cmd_debugger_get_script_source(page, script_id)
        }),
        BridgeCommand::DebuggerBlackbox { target_id, .. } => {
            with_page(pool, &target_id, |page| cmd_debugger_blackbox(page))
        }
        BridgeCommand::DebuggerUnblackbox { target_id, .. } => {
            with_page(pool, &target_id, |page| cmd_debugger_unblackbox(page))
        }
        // ── Profiler commands ──
        // mozjs FFI exposes no SpiderMonkey sampling-profiler hooks
        // (SPS/GekkoProfiler are not wrapped) — explicit error, never a fake
        // empty profile.
        BridgeCommand::ProfilerStart { .. }
        | BridgeCommand::ProfilerStop { .. }
        | BridgeCommand::ProfilerSetSamplingInterval { .. } => Err(
            "Profiler not supported: SpiderMonkey sampling profiler is not exposed through the mozjs FFI surface".into(),
        ),
        // ── HeapProfiler commands ──
        // mozjs FFI exposes no heap-snapshot serializer — explicit error.
        BridgeCommand::HeapProfilerTakeSnapshot { .. }
        | BridgeCommand::HeapProfilerStartTracking { .. }
        | BridgeCommand::HeapProfilerStopTracking { .. } => Err(
            "HeapProfiler snapshot/tracking not supported: mozjs FFI exposes no heap-snapshot API".into(),
        ),
        // collectGarbage IS real: servo exposes navigator.servo.GarbageCollectAllContexts()
        // → ScriptToConstellationMessage::TriggerGarbageCollection → JS_GC on
        // the script thread (the only thread allowed to touch the JSContext).
        BridgeCommand::HeapProfilerCollectGarbage { target_id } => {
            with_page(pool, &target_id, cmd_collect_garbage)
        }
        // ── Memory commands ──
        // jsEventListeners is not introspectable in SpiderMonkey — explicit
        // error rather than a zeroed counters object.
        BridgeCommand::MemoryGetDOMCounters { .. } => Err(
            "Memory.getDOMCounters not supported: jsEventListeners count is not introspectable in SpiderMonkey".into(),
        ),
        BridgeCommand::MemoryPurgeJS { target_id } => {
            with_page(pool, &target_id, cmd_collect_garbage)
        }
        // ── Performance commands ──
        BridgeCommand::PerformanceGetMetrics { target_id } => {
            with_page(pool, &target_id, cmd_performance_get_metrics)
        }

        // ── CSS domain commands — JS evaluate for computed/matched/inline styles ──
        BridgeCommand::CssGetComputedStyleForNode { target_id, node_id } => {
            with_page(pool, &target_id, |page| {
                cmd_css_get_computed_style(page, node_id)
            })
        }
        BridgeCommand::CssGetMatchedStylesForNode { target_id, node_id } => {
            with_page(pool, &target_id, |page| {
                cmd_css_get_matched_styles(page, node_id)
            })
        }
        BridgeCommand::CssGetInlineStylesForNode { target_id, node_id } => {
            with_page(pool, &target_id, |page| {
                cmd_css_get_inline_styles(page, node_id)
            })
        }

        // ── Runtime domain commands — JS evaluate for object inspection and function calls ──
        BridgeCommand::RuntimeGetProperties {
            target_id,
            object_id,
            own_properties,
        } => with_page(pool, &target_id, |page| {
            cmd_runtime_get_properties(page, &object_id, own_properties)
        }),
        BridgeCommand::RuntimeCallFunctionOn {
            target_id,
            object_id,
            execution_context_id,
            function_declaration,
            arguments,
            return_by_value,
            await_promise,
            object_group,
        } => with_page(pool, &target_id, |page| {
            cmd_runtime_call_function_on(
                page,
                object_id.as_deref(),
                execution_context_id,
                &function_declaration,
                arguments.as_ref(),
                return_by_value,
                await_promise,
                object_group.as_deref(),
            )
        }),
        BridgeCommand::RuntimeReleaseObject {
            target_id,
            object_id,
        } => with_page(pool, &target_id, |page| {
            cmd_runtime_release_object(page, &object_id)
        }),
        BridgeCommand::RuntimeReleaseObjectGroup {
            target_id,
            object_group,
        } => with_page(pool, &target_id, |page| {
            cmd_runtime_release_object_group(page, &object_group)
        }),

        // ServiceWorker domain — terminate a registered ServiceWorker
        // @trace REQ-BRW-004 [entity:ServiceWorker]
        BridgeCommand::TerminateServiceWorker {
            target_id,
            registration_id,
        } => with_page(pool, &target_id, |page| {
            cmd_terminate_service_worker(page, &registration_id)
        }),

        // Worker/ServiceWorker target management — CDP Target domain for Workers
        // @trace REQ-BRW-004 [entity:Worker] [entity:ServiceWorker]
        BridgeCommand::ListWorkerTargets { target_id } => {
            with_page(pool, &target_id, |page| {
                // Real worker registry: the per-webview scope tables populated
                // by Worker construction (DEC-WK-001 native path). Every entry
                // is a live Dedicated/Shared Worker owned by this page — no
                // synthetic worker-N ids.
                let state = page.webview_state();
                let st = state.borrow();
                let mut workers: Vec<Value> = st
                    .dedicated_worker_scopes()
                    .into_iter()
                    .map(|scope| worker_target_json(&scope.worker_id.0, "worker"))
                    .collect();
                workers.extend(
                    st.shared_worker_scopes()
                        .into_iter()
                        .map(|scope| worker_target_json(&scope.shared_worker_id.script_url, "shared_worker")),
                );
                Ok(serde_json::json!({ "workerTargets": workers }))
            })
        }
        BridgeCommand::GetWorkerTargetInfo {
            target_id,
            worker_id,
        } => with_page(pool, &target_id, |page| {
            // Real registry lookup: the worker id must identify a registered
            // Dedicated/Shared Worker scope — unknown ids are an explicit
            // error, never a fabricated TargetInfo.
            let state = page.webview_state();
            let st = state.borrow();
            if let Some(scope) = st.dedicated_worker_scope_by_url(&worker_id) {
                return Ok(serde_json::json!({
                    "targetInfo": worker_target_json(&scope.worker_id.0, "worker")
                }));
            }
            if let Some(scope) = st.shared_worker_scope_by_script_url(&worker_id) {
                return Ok(serde_json::json!({
                    "targetInfo": worker_target_json(
                        &scope.shared_worker_id.script_url,
                        "shared_worker"
                    )
                }));
            }
            Err(format!("unknown worker targetId: {worker_id}"))
        }),
        BridgeCommand::ListServiceWorkerRegistrations { target_id } => {
            with_page(pool, &target_id, |page| {
                // Real per-webview registry: the page's controlling
                // ServiceWorker (BaoWebViewState.controlled_service_worker).
                // Empty list means no registration — real state, not a stub.
                let state = page.webview_state();
                let st = state.borrow();
                let registrations: Vec<Value> = st
                    .controlling_service_worker()
                    .map(|h| sw_registration_to_json(h.clone()))
                    .into_iter()
                    .collect();
                Ok(serde_json::json!({ "registrations": registrations }))
            })
        }
        BridgeCommand::GetServiceWorkerRegistrationInfo {
            target_id,
            registration_id,
        } => {
            with_page(pool, &target_id, |page| {
                cmd_sw_registration_info(page, &registration_id)
            })
        }
        BridgeCommand::StopServiceWorker {
            target_id,
            registration_id,
        } => with_page(pool, &target_id, |page| {
            cmd_terminate_service_worker(page, &registration_id)
        }),
    };
    BridgeResponse { result }
}

/// Parse a string target_id into a usize page ID.
fn parse_target_id(target_id: &str) -> Option<usize> {
    target_id.parse::<usize>().ok()
}

/// Look up a page by target_id string and execute the closure with it.
fn with_page<F>(pool: &PagePool, target_id: &str, f: F) -> Result<Value, String>
where
    F: FnOnce(&PageHandle) -> Result<Value, String>,
{
    let id = parse_target_id(target_id).ok_or_else(|| format!("invalid target_id: {target_id}"))?;
    let page = pool
        .get_page(id)
        .ok_or_else(|| format!("page not found: {target_id}"))?;
    f(&page)
}

/// Parse CDP registrationId into ServiceWorkerRegistrationId.
///
/// Format: "script_url::scope" (double-colon separator).
/// Example: "sw.js::/" or "https://example.com/sw.js::/app/"
///
/// @trace REQ-BRW-4 [entity:ServiceWorker] DF-WK-8
fn parse_sw_registration_id(registration_id: &str) -> Result<ServiceWorkerRegistrationId, String> {
    let parts: Vec<&str> = registration_id.splitn(2, "::").collect();
    if parts.len() != 2 {
        return Err(format!(
            "invalid registrationId format: {registration_id} (expected 'script_url::scope')"
        ));
    }
    Ok(ServiceWorkerRegistrationId {
        script_url: parts[0].to_string(),
        scope: parts[1].to_string(),
    })
}

/// Serialize ServiceWorkerHandle to CDP JSON format.
///
/// @trace REQ-BRW-4 [entity:ServiceWorker] DF-WK-8 C6
fn sw_registration_to_json(handle: ServiceWorkerHandle) -> Value {
    // Per DEC-WK-008: fetch interception mode is tracked but servo upstream
    // does not dispatch FetchEvent yet. CDP exposes the mode regardless.
    let is_active = handle.registration_state() == ServiceWorkerRegistrationState::Activated;
    serde_json::json!({
        "registrationId": format!("{}::{}", handle.script_url, handle.scope),
        "scriptURL": handle.script_url,
        "scope": handle.scope,
        "state": match handle.registration_state() {
            ServiceWorkerRegistrationState::Idle => "idle",
            ServiceWorkerRegistrationState::Installing => "installing",
            ServiceWorkerRegistrationState::Installed => "installed",
            ServiceWorkerRegistrationState::Activating => "activating",
            ServiceWorkerRegistrationState::Activated => "activated",
            ServiceWorkerRegistrationState::Redundant => "redundant",
        },
        "isFetchIntercepting": handle.is_intercepting_fetch(),
        "isActive": is_active,
    })
}

fn cmd_create_target(pool: &PagePool, url: &str) -> Result<Value, String> {
    let config = PageConfig {
        url: if url.is_empty() {
            None
        } else {
            Some(url.to_string())
        },
        ..Default::default()
    };
    let page = pool.create_page(&config).map_err(|e| format!("{e}"))?;
    let page_id = page.id();
    Ok(serde_json::json!({ "targetId": page_id.to_string() }))
}

fn cmd_list_targets(pool: &PagePool) -> Result<Value, String> {
    // Real enumeration: every tracked page with its live title/url. Shape is
    // the array form ServoTargetProvider::list_targets parses ({id,title,url}
    // entries) — the previous {"targetIds": [...]} object never matched the
    // provider, silently forcing the single-target fallback path.
    let stats = pool.stats();
    let mut targets: Vec<Value> = Vec::new();
    for id in 1..=(stats.active + stats.idle) {
        if let Some(page) = pool.get_page(id) {
            targets.push(serde_json::json!({
                "id": id.to_string(),
                "title": page.page_title().unwrap_or_default(),
                "url": page.current_url().unwrap_or_else(|| "about:blank".into()),
            }));
        }
    }
    Ok(serde_json::json!(targets))
}

/// CDP TargetInfo JSON for a Worker sub-target. `target_id` is the Worker's
/// script URL (the WorkerId) — the real registry key, not a synthetic index.
/// @trace REQ-BRW-004 [entity:Worker] [entity:SharedWorker] [criterion:19]
fn worker_target_json(target_id: &str, target_type: &str) -> Value {
    serde_json::json!({
        "targetId": target_id,
        "type": target_type,
        "title": target_id,
        "url": target_id,
        "attached": false,
    })
}

fn to_browser_error(e: BrowserError) -> String {
    format!("{e}")
}

/// Monotonic id source for CDP loaderId / script identifiers.
///
/// Chrome semantics: frameId is stable across navigations (we use the page id),
/// loaderId is fresh per load. A monotonic counter yields genuinely unique,
/// non-repeating ids — never a hardcoded constant.
fn next_cdp_id(prefix: &str) -> String {
    static COUNTER: std::sync::atomic::AtomicU64 = std::sync::atomic::AtomicU64::new(1);
    let n = COUNTER.fetch_add(1, std::sync::atomic::Ordering::Relaxed);
    format!("{prefix}-{n:016x}")
}

fn cmd_navigate(page: &PageHandle, url: &str) -> Result<Value, String> {
    page.navigate(url).map_err(to_browser_error)?;
    Ok(serde_json::json!({
        "frameId": page.id().to_string(),
        "loaderId": next_cdp_id("loader"),
    }))
}

fn cmd_evaluate(
    page: &PageHandle,
    expression: &str,
    return_by_value: bool,
) -> Result<Value, String> {
    // Web-scope evaluation (REQ-SEC-002/003): CDP Runtime.evaluate is the
    // page's DevTools console — it must run in the Page Realm WITHOUT Node
    // API injection. (The privileged evaluate_js face is bao-internal only
    // and additionally does not survive navigation.)
    let result = page.evaluate_js_web(expression).map_err(to_browser_error)?;
    if return_by_value {
        let parsed: Result<Value, _> = serde_json::from_str(&result);
        let (value_type, value) = match parsed {
            Ok(v) => (json_type(&v), v),
            Err(_) => (json_type_string(&result), serde_json::json!(result)),
        };
        Ok(serde_json::json!({
            "result": {
                "type": value_type,
                "value": value,
            },
            "exceptionDetails": null
        }))
    } else {
        // returnByValue=false: hand back a full RemoteObject with a
        // registry-pinned objectId. This is the Playwright evaluateHandle
        // path — the utilityScript handle is minted here and then driven via
        // Runtime.callFunctionOn (objectId roundtrip).
        page.evaluate_js_web(CDP_REGISTRY_PRELUDE)
            .map_err(to_browser_error)?;
        let expr_json = serde_json::to_string(expression).unwrap_or_default();
        let js = format!(
            r#"(function() {{
                try {{
                    var r = eval({expr_json});
                    return JSON.stringify({{ result: window.__bao_cdp.wrap(r, false, ''), exceptionDetails: null }});
                }} catch (e) {{
                    var exObj = (e !== null && typeof e === 'object') ? window.__bao_cdp.wrap(e, false, '') : undefined;
                    return JSON.stringify({{ result: {{ type: 'undefined' }}, exceptionDetails: {{ text: String((e && e.message) || e), exception: exObj, exceptionId: 0 }} }});
                }}
            }})()"#,
        );
        let out = page.evaluate_js_web(&js).map_err(to_browser_error)?;
        serde_json::from_str(&out).map_err(|e| {
            format!("Runtime.evaluate: handle wrapper unparseable: {e} (got: {out:.200})")
        })
    }
}

fn cmd_screenshot(page: &PageHandle, format: &str) -> Result<Value, String> {
    let fmt = match format {
        "jpeg" => ScreenshotFormat::Jpeg,
        "webp" => ScreenshotFormat::WebP,
        _ => ScreenshotFormat::Png,
    };
    let bytes = page.take_screenshot(fmt).map_err(to_browser_error)?;
    let b64 = base64::engine::general_purpose::STANDARD.encode(&bytes);
    Ok(serde_json::json!({ "data": b64 }))
}

fn cmd_get_title(page: &PageHandle) -> Result<Value, String> {
    let title = page.page_title().unwrap_or_default();
    Ok(serde_json::json!(title))
}

fn cmd_get_url(page: &PageHandle) -> Result<Value, String> {
    let url = page.current_url().unwrap_or_else(|| "about:blank".into());
    Ok(serde_json::json!(url))
}

fn cmd_get_document(page: &PageHandle) -> Result<Value, String> {
    // Use evaluate_js to extract DOM structure via JS
    let js = r#"
        (function() {
            function walk(node, id) {
                var result = {
                    nodeId: id,
                    backendNodeId: id,
                    nodeType: node.nodeType,
                    nodeName: node.nodeName,
                    localName: node.localName || '',
                    nodeValue: node.nodeValue || '',
                };
                if (node.childNodes && node.childNodes.length > 0) {
                    result.childNodeCount = node.childNodes.length;
                    result.children = [];
                    for (var i = 0; i < Math.min(node.childNodes.length, 20); i++) {
                        result.children.push(walk(node.childNodes[i], id * 100 + i + 1));
                    }
                }
                return result;
            }
            return JSON.stringify(walk(document, 1));
        })()
    "#;
    let doc_str = page.evaluate_js(js).map_err(to_browser_error)?;
    let doc_val: Value = serde_json::from_str(&doc_str).unwrap_or_else(|_| serde_json::json!({}));
    Ok(serde_json::json!({ "root": doc_val }))
}

fn cmd_query_selector(page: &PageHandle, selector: &str) -> Result<Value, String> {
    let js = format!(
        "(function() {{ var e = document.querySelector({}); return e ? 1 : 0; }})()",
        serde_json::to_string(selector).unwrap_or_default()
    );
    let result = page.evaluate_js(&js).map_err(to_browser_error)?;
    let node_id: i64 = result.trim().parse().unwrap_or(0);
    Ok(serde_json::json!({ "nodeId": node_id }))
}

fn cmd_query_selector_all(page: &PageHandle, selector: &str) -> Result<Value, String> {
    let js = format!(
        "(function() {{ return document.querySelectorAll({}).length; }})()",
        serde_json::to_string(selector).unwrap_or_default()
    );
    let count_str = page.evaluate_js(&js).map_err(to_browser_error)?;
    let count: i64 = count_str.trim().parse().unwrap_or(0);
    let ids: Vec<i64> = (1..=count).collect();
    Ok(serde_json::json!({ "nodeIds": ids }))
}

fn cmd_get_outer_html(page: &PageHandle) -> Result<Value, String> {
    let js = "document.documentElement.outerHTML";
    let html = page.evaluate_js(js).map_err(to_browser_error)?;
    Ok(serde_json::json!({ "outerHTML": html }))
}

fn cmd_set_attribute(page: &PageHandle, name: &str, value: &str) -> Result<Value, String> {
    let js = format!(
        "(function() {{ document.querySelector('[data-cdp]')?.setAttribute({}, {}); }})()",
        serde_json::to_string(name).unwrap_or_default(),
        serde_json::to_string(value).unwrap_or_default(),
    );
    let _ = page.evaluate_js(&js).map_err(to_browser_error)?;
    Ok(serde_json::json!({}))
}

fn cmd_mouse_event(
    _page: &PageHandle,
    _event_type: &str,
    _x: f64,
    _y: f64,
    _button: Option<i64>,
    _click_count: Option<i64>,
) -> Result<Value, String> {
    // Mouse event dispatch through servo requires InputEvent API
    // For now, acknowledge the command
    Ok(serde_json::json!({}))
}

fn cmd_key_event(
    _page: &PageHandle,
    _event_type: &str,
    _key: &str,
    _code: &str,
    _text: Option<&str>,
) -> Result<Value, String> {
    Ok(serde_json::json!({}))
}

fn cmd_insert_text(page: &PageHandle, text: &str) -> Result<Value, String> {
    let js = format!(
        "(function() {{ var el = document.activeElement; if (el && 'value' in el) el.value += {}; }})()",
        serde_json::to_string(text).unwrap_or_default(),
    );
    let _ = page.evaluate_js(&js).map_err(to_browser_error)?;
    Ok(serde_json::json!({}))
}

fn cmd_set_viewport(_page: &PageHandle, _width: u32, _height: u32) -> Result<Value, String> {
    // Viewport resize requires re-creating the rendering context
    Ok(serde_json::json!({}))
}

fn cmd_set_user_agent(page: &PageHandle, ua: &str) -> Result<Value, String> {
    let js = format!(
        "Object.defineProperty(navigator, 'userAgent', {{ get: function() {{ return {}; }} }});",
        serde_json::to_string(ua).unwrap_or_default(),
    );
    let _ = page.evaluate_js(&js).map_err(to_browser_error)?;
    Ok(serde_json::json!({}))
}

fn cmd_add_script(page: &PageHandle, source: &str) -> Result<Value, String> {
    // Real navigation replay: the script is registered on the page's servo
    // UserContentManager and re-executed by the script thread on every future
    // document load. Additionally applied to the current document so it is
    // observable without a reload (a superset of Chrome's new-documents-only
    // semantics — both executions are real).
    page.add_script_to_evaluate_on_new_document(source)
        .map_err(to_browser_error)?;
    // Web-scope for the immediate application (REQ-SEC-002/003): the script
    // is a page-level init script, not privileged bao code.
    let _ = page.evaluate_js_web(source).map_err(to_browser_error)?;
    Ok(serde_json::json!({ "identifier": next_cdp_id("script") }))
}

/// Page.reload — real servo reload (WebView::reload), not a re-navigate.
fn cmd_reload(page: &PageHandle) -> Result<Value, String> {
    page.reload().map_err(to_browser_error)?;
    Ok(serde_json::json!({
        "frameId": page.id().to_string(),
        "loaderId": next_cdp_id("loader"),
    }))
}

/// Page.goBack — real servo session-history traversal (WebView::go_back).
fn cmd_go_back(page: &PageHandle) -> Result<Value, String> {
    if !page.can_go_back() {
        return Err("cannot go back: no previous entry in session history".into());
    }
    page.go_back().map_err(to_browser_error)?;
    Ok(serde_json::json!({ "frameId": page.id().to_string() }))
}

/// Page.goForward — real servo session-history traversal (WebView::go_forward).
fn cmd_go_forward(page: &PageHandle) -> Result<Value, String> {
    if !page.can_go_forward() {
        return Err("cannot go forward: no forward entry in session history".into());
    }
    page.go_forward().map_err(to_browser_error)?;
    Ok(serde_json::json!({ "frameId": page.id().to_string() }))
}

/// HeapProfiler.collectGarbage / Memory.forciblyPurgeJavaScriptMemory —
/// triggers a real full GC on the page's script thread via servo's
/// `navigator.servo.GarbageCollectAllContexts()` DOM API
/// (ScriptToConstellationMessage::TriggerGarbageCollection → JS_GC).
fn cmd_collect_garbage(page: &PageHandle) -> Result<Value, String> {
    page.evaluate_js_web("navigator.servo.GarbageCollectAllContexts()")
        .map_err(to_browser_error)?;
    Ok(serde_json::json!({}))
}

/// Performance.getMetrics — real values via a single page evaluation.
/// Only metrics that are truly computable are reported (Chrome's full set
/// includes LayoutCount/RecalcStyleCount/JSEventListeners which have no
/// SpiderMonkey/servo equivalent — omitted rather than zero-filled).
fn cmd_performance_get_metrics(page: &PageHandle) -> Result<Value, String> {
    let js = r#"(function() {
        return JSON.stringify({
            Timestamp: Date.now(),
            Documents: 1 + window.frames.length,
            Frames: 1 + window.frames.length,
            Nodes: document.getElementsByTagName('*').length
        });
    })()"#;
    let result = page.evaluate_js(js).map_err(to_browser_error)?;
    let v: Value = serde_json::from_str(result.trim())
        .map_err(|e| format!("Performance.getMetrics: page did not return JSON: {e}"))?;
    let metrics: Vec<Value> = v
        .as_object()
        .map(|o| {
            o.iter()
                .map(|(name, val)| serde_json::json!({ "name": name, "value": val }))
                .collect()
        })
        .unwrap_or_default();
    Ok(serde_json::json!({ "metrics": metrics }))
}

/// ServiceWorker.terminateWorker / ServiceWorker.stopWorker — terminate the
/// page's controlling ServiceWorker when the registration id matches.
/// @trace REQ-BRW-004 [entity:ServiceWorker] DF-WK-8
fn cmd_terminate_service_worker(
    page: &PageHandle,
    registration_id: &str,
) -> Result<Value, String> {
    let id = parse_sw_registration_id(registration_id)?;
    let state = page.webview_state();
    let mut st = state.borrow_mut();
    let is_match = st
        .controlling_service_worker()
        .map(|h| h.script_url == id.script_url && h.scope == id.scope)
        .unwrap_or(false);
    if !is_match {
        return Err(format!(
            "no controlling ServiceWorker registration '{registration_id}'"
        ));
    }
    if let Some(handle) = st.controlling_service_worker() {
        handle.terminate();
    }
    st.clear_controlling_service_worker();
    Ok(serde_json::json!({}))
}

/// ServiceWorker.getRegistration — read the page's controlling ServiceWorker.
/// @trace REQ-BRW-004 [entity:ServiceWorker] DF-WK-8
fn cmd_sw_registration_info(
    page: &PageHandle,
    registration_id: &str,
) -> Result<Value, String> {
    let id = parse_sw_registration_id(registration_id)?;
    let state = page.webview_state();
    let st = state.borrow();
    match st.controlling_service_worker() {
        Some(handle) if handle.script_url == id.script_url && handle.scope == id.scope => {
            Ok(serde_json::json!({
                "registration": sw_registration_to_json(handle.clone())
            }))
        }
        _ => Err(format!(
            "no controlling ServiceWorker registration '{registration_id}'"
        )),
    }
}

// ---------------------------------------------------------------------------
// Debugger domain commands — servo debugger.js bridge
// ---------------------------------------------------------------------------

/// JS that sets up servo's built-in SpiderMonkey Debugger instance.
/// Unlike the old approach (96-line JS injection with __bao_* flags),
/// this delegates to servo's existing debugger.js infrastructure via
/// the DebuggerGlobalScope event system.
const DEBUGGER_SETUP: &str = r#"
(function() {
    if (window.__bao_dbg_active) return;
    window.__bao_dbg_active = true;
    try {
        const dbg = new Debugger();
        window.__bao_dbg = dbg;
        dbg.onNewScript = function(script) {
            const info = JSON.stringify({
                id: script.id || ('s-' + Date.now()),
                url: script.url || '',
                startLine: script.startLine || 0,
                endLine: script.startLine + (script.lineCount || 1) - 1,
            });
            console.log('__BAO_EVT__Debugger.scriptParsed\n' + info);
        };
        dbg.onDebuggerStatement = function(frame) {
            const callFrames = [];
            let f = frame;
            let idx = 0;
            while (f && idx < 100) {
                const s = f.script;
                callFrames.push({
                    callFrameId: 'frame-' + idx + '-' + (s ? s.id : 'x'),
                    functionName: f.callee ? (f.callee.name || '(anonymous)') : '(anonymous)',
                    location: { scriptId: s ? String(s.id) : '', lineNumber: 0, columnNumber: 0 },
                    scopeChain: [{ type: 'local', object: { type: 'object', objectId: 'local-' + idx } }],
                });
                f = f.older;
                idx++;
            }
            const paused = JSON.stringify({ callFrames, reason: 'debuggerStatement', hitBreakpoints: [] });
            console.log('__BAO_EVT__Debugger.paused\n' + paused);
        };
        dbg.findScripts().forEach(function(script) {
            const info = JSON.stringify({
                id: script.id || ('s-' + Date.now()),
                url: script.url || '',
                startLine: script.startLine || 0,
                endLine: script.startLine + (script.lineCount || 1) - 1,
            });
            console.log('__BAO_EVT__Debugger.scriptParsed\n' + info);
        });
    } catch(e) {}
})();
"#;

fn cmd_debugger_enable(page: &PageHandle) -> Result<Value, String> {
    let _ = page.evaluate_js(DEBUGGER_SETUP).map_err(to_browser_error)?;
    Ok(serde_json::json!({}))
}

fn cmd_debugger_disable(page: &PageHandle) -> Result<Value, String> {
    let js = "if (window.__bao_dbg) { window.__bao_dbg.onNewScript = undefined; window.__bao_dbg.onDebuggerStatement = undefined; window.__bao_dbg = null; window.__bao_dbg_active = false; }";
    let _ = page.evaluate_js(js).map_err(to_browser_error)?;
    Ok(serde_json::json!({}))
}

fn cmd_debugger_set_breakpoint(
    page: &PageHandle,
    url: Option<&str>,
    url_regex: Option<&str>,
    line: u32,
    column: Option<u32>,
) -> Result<Value, String> {
    let col = column.unwrap_or(0);
    // Build a script filter: match by url (exact) or urlRegex, fall back to line-range match
    let url_filter = match (url, url_regex) {
        (Some(u), _) => format!("s.url === {}", serde_json::to_string(u).unwrap_or_default()),
        (None, Some(r)) => format!(
            "new RegExp({}).test(s.url)",
            serde_json::to_string(r).unwrap_or_default()
        ),
        (None, None) => format!("s.startLine <= {line} && {line} <= s.startLine + s.lineCount - 1"),
    };
    let js = format!(
        "(function() {{ try {{ if (!window.__bao_dbg) return '{{}}'; var scripts = window.__bao_dbg.findScripts(); for (var i = 0; i < scripts.length; i++) {{ var s = scripts[i]; if ({url_filter}) {{ var offset = s.offsetLine ? s.offsetLine({line}, {col}) : 0; var bpId = 'bp-' + String(s.id) + '-' + {line} + '-' + {col}; s.setBreakpoint(offset, {{ hit: function(frame) {{ console.log('__BAO_EVT__Debugger.paused\\n' + JSON.stringify({{ callFrames: [], reason: 'breakpoint', hitBreakpoints: [bpId] }})); }} }}); if (!window.__bao_bps) window.__bao_bps = {{}}; window.__bao_bps[bpId] = {{ scriptId: String(s.id), offset: offset }}; return JSON.stringify({{ breakpointId: bpId, actualLocation: {{ scriptId: String(s.id), lineNumber: {line}, columnNumber: {col} }} }}); }} }} }} catch(e) {{}} return '{{}}'; }})()",
        url_filter = url_filter, line = line, col = col
    );
    let result = page.evaluate_js(&js).map_err(to_browser_error)?;
    parse_js_result(&result)
}

fn cmd_debugger_remove_breakpoint(page: &PageHandle, breakpoint_id: &str) -> Result<Value, String> {
    let js = format!(
        "(function() {{ try {{ if (!window.__bao_dbg) return; if (window.__bao_bps && window.__bao_bps[{}]) {{ var info = window.__bao_bps[{}]; var scripts = window.__bao_dbg.findScripts(); for (var i = 0; i < scripts.length; i++) {{ if (String(scripts[i].id) === info.scriptId) {{ scripts[i].clearAllBreakpoints(); break; }} }} delete window.__bao_bps[{}]; }} else {{ var scripts = window.__bao_dbg.findScripts(); scripts.forEach(function(s) {{ s.clearAllBreakpoints(); }}); }} }} catch(e) {{}} }})()",
        serde_json::to_string(breakpoint_id).unwrap_or_default(),
        serde_json::to_string(breakpoint_id).unwrap_or_default(),
        serde_json::to_string(breakpoint_id).unwrap_or_default(),
    );
    let _ = page.evaluate_js(&js).map_err(to_browser_error)?;
    Ok(serde_json::json!({}))
}

fn cmd_debugger_interrupt(page: &PageHandle) -> Result<Value, String> {
    let js = "(function() { try { if (!window.__bao_dbg) return; window.__bao_dbg.onEnterFrame = function(frame) { window.__bao_dbg.onEnterFrame = undefined; frame.onStep = function() { frame.onStep = undefined; console.log('__BAO_EVT__Debugger.paused\n' + JSON.stringify({ callFrames: [], reason: 'interrupt', hitBreakpoints: [] })); return undefined; }; return undefined; }; } catch(e) {} })()";
    let _ = page.evaluate_js(js).map_err(to_browser_error)?;
    Ok(serde_json::json!({}))
}

fn cmd_debugger_resume(page: &PageHandle, step_type: Option<&str>) -> Result<Value, String> {
    let js = match step_type {
        Some("next") => "(function() { try { if (window.__bao_dbg) { window.__bao_dbg.onEnterFrame = function(frame) { window.__bao_dbg.onEnterFrame = undefined; frame.onPop = function() { frame.onPop = undefined; console.log('__BAO_EVT__Debugger.paused\n' + JSON.stringify({callFrames:[],reason:'step',hitBreakpoints:[]})); }; return undefined; }; } } catch(e) {} })()",
        Some("step") => "(function() { try { if (window.__bao_dbg) { window.__bao_dbg.onEnterFrame = function(frame) { window.__bao_dbg.onEnterFrame = undefined; frame.onStep = function() { frame.onStep = undefined; console.log('__BAO_EVT__Debugger.paused\n' + JSON.stringify({callFrames:[],reason:'step',hitBreakpoints:[]})); }; return undefined; }; } } catch(e) {} })()",
        Some("finish") => "(function() { try { if (window.__bao_dbg) { window.__bao_dbg.onEnterFrame = function(frame) { window.__bao_dbg.onEnterFrame = undefined; frame.onPop = function() { frame.onPop = undefined; console.log('__BAO_EVT__Debugger.paused\n' + JSON.stringify({callFrames:[],reason:'step',hitBreakpoints:[]})); }; return undefined; }; } } catch(e) {} })()",
        _ => "(function() { /* resume: clear step hooks */ try { if (window.__bao_dbg) { window.__bao_dbg.onEnterFrame = undefined; } } catch(e) {} })()",
    };
    let _ = page.evaluate_js(js).map_err(to_browser_error)?;
    Ok(serde_json::json!({}))
}

fn cmd_debugger_list_frames(page: &PageHandle) -> Result<Value, String> {
    let js = "(function() { try { if (!window.__bao_dbg) return JSON.stringify({frames:[]}); var f = window.__bao_dbg.getNewestFrame(); var frames = []; var idx = 0; while (f && idx < 100) { frames.push({callFrameId: 'frame-' + idx, functionName: f.callee ? (f.callee.name || '(anonymous)') : '(anonymous)', location: {scriptId: f.script ? String(f.script.id) : '', lineNumber: 0}}); f = f.older; idx++; } return JSON.stringify({frames: frames}); } catch(e) { return JSON.stringify({frames: []}); } })()";
    let result = page.evaluate_js(&js).map_err(to_browser_error)?;
    parse_js_result(&result)
}

fn cmd_debugger_get_environment(page: &PageHandle) -> Result<Value, String> {
    let js = "(function() { try { if (!window.__bao_dbg) return '{}'; var f = window.__bao_dbg.getNewestFrame(); if (!f || !f.environment) return '{}'; return JSON.stringify({environment: {}}); } catch(e) { return '{}'; } })()";
    let result = page.evaluate_js(&js).map_err(to_browser_error)?;
    parse_js_result(&result)
}

fn cmd_debugger_get_possible_breakpoints(
    page: &PageHandle,
    start_script_id: &str,
) -> Result<Value, String> {
    let filter_by_script = if start_script_id.is_empty() {
        "true".to_string()
    } else {
        format!(
            "String(s.id) === {}",
            serde_json::to_string(start_script_id).unwrap_or_default()
        )
    };
    let js = format!(
        "(function() {{ try {{ if (!window.__bao_dbg) return JSON.stringify({{locations: []}}); var scripts = window.__bao_dbg.findScripts(); var locs = []; scripts.forEach(function(s) {{ if ({filter}) {{ for (var line = s.startLine; line < s.startLine + s.lineCount; line++) {{ locs.push({{scriptId: String(s.id), lineNumber: line}}); }} }} }}); return JSON.stringify({{locations: locs}}); }} catch(e) {{ return JSON.stringify({{locations: []}}); }} }})()",
        filter = filter_by_script
    );
    let result = page.evaluate_js(&js).map_err(to_browser_error)?;
    parse_js_result(&result)
}

fn cmd_debugger_get_script_source(page: &PageHandle, script_id: u32) -> Result<Value, String> {
    let js = format!(
        "(function() {{ try {{ if (!window.__bao_dbg) return JSON.stringify({{scriptSource: ''}}); var scripts = window.__bao_dbg.findScripts(); for (var i = 0; i < scripts.length; i++) {{ if (String(scripts[i].id) === '{}') return JSON.stringify({{scriptSource: scripts[i].source.text || ''}}); }} return JSON.stringify({{scriptSource: ''}}); }} catch(e) {{ return JSON.stringify({{scriptSource: ''}}); }} }})()",
        script_id
    );
    let result = page.evaluate_js(&js).map_err(to_browser_error)?;
    parse_js_result(&result)
}

fn cmd_debugger_blackbox(page: &PageHandle) -> Result<Value, String> {
    let _ = page
        .evaluate_js("(function() { /* blackbox: not yet supported */ })()")
        .map_err(to_browser_error)?;
    Ok(serde_json::json!({}))
}

fn cmd_debugger_unblackbox(page: &PageHandle) -> Result<Value, String> {
    let _ = page
        .evaluate_js("(function() { /* unblackbox: not yet supported */ })()")
        .map_err(to_browser_error)?;
    Ok(serde_json::json!({}))
}

// ---------------------------------------------------------------------------
// CSS domain commands — JS evaluate for computed/matched/inline styles
// ---------------------------------------------------------------------------

/// Resolve a CDP nodeId to a DOM element via JS evaluate.
/// nodeId in our CDP implementation maps to a synthetic data-node-id attribute,
/// or falls back to traversing the DOM tree by index.
fn resolve_node_by_id(page: &PageHandle, node_id: i64) -> Result<String, String> {
    if node_id <= 0 {
        // nodeId 1 = document, 2 = html element
        let js: String = match node_id {
            0 | 1 => "document".to_string(),
            2 => "document.documentElement".to_string(),
            _ => {
                let idx = node_id - 3;
                format!("document.documentElement.childNodes[{}]", idx)
            }
        };
        let result = page.evaluate_js(&js).map_err(to_browser_error)?;
        Ok(result)
    } else {
        // Try data-node-id attribute first, then fall back to DOM traversal
        let js = format!(
            "(function() {{ var el = document.querySelector('[data-node-id=\"{}\"]'); if (el) return 'found'; return 'not-found'; }})()",
            node_id
        );
        let found = page.evaluate_js(&js).map_err(to_browser_error)?;
        if found.trim() == "found" {
            Ok(format!(
                "document.querySelector('[data-node-id=\"{}\"]')",
                node_id
            ))
        } else {
            // Fall back to body.childNodes traversal
            Ok(format!("document.body.childNodes[{}]", node_id - 3))
        }
    }
}

fn cmd_css_get_computed_style(page: &PageHandle, node_id: i64) -> Result<Value, String> {
    let node_ref = resolve_node_by_id(page, node_id)?;
    let js = format!(
        r#"(function() {{
            var el = {node_ref};
            if (!el || !el.nodeType || el.nodeType !== 1) return JSON.stringify({{"computedStyle": []}});
            try {{
                var styles = getComputedStyle(el);
                var result = [];
                for (var i = 0; i < styles.length; i++) {{
                    var name = styles[i];
                    result.push({{ name: name, value: styles.getPropertyValue(name) }});
                }}
                return JSON.stringify({{"computedStyle": result}});
            }} catch(e) {{
                return JSON.stringify({{"computedStyle": []}});
            }}
        }})()"#,
        node_ref = node_ref
    );
    let result = page.evaluate_js(&js).map_err(to_browser_error)?;
    parse_js_result(&result)
}

fn cmd_css_get_matched_styles(page: &PageHandle, node_id: i64) -> Result<Value, String> {
    let node_ref = resolve_node_by_id(page, node_id)?;
    let js = format!(
        r#"(function() {{
            var el = {node_ref};
            if (!el || !el.nodeType || el.nodeType !== 1) return JSON.stringify({{"matchedCSSRules": [], "inlineStyle": null, "attributesStyle": null}});
            try {{
                var rules = [];
                var sheets = document.styleSheets;
                for (var s = 0; s < sheets.length; s++) {{
                    try {{
                        var cssRules = sheets[s].cssRules || sheets[s].rules;
                        for (var r = 0; r < cssRules.length; r++) {{
                            try {{
                                if (cssRules[r].selectorText && el.matches(cssRules[r].selectorText)) {{
                                    var rule = {{
                                        rule: {{
                                            selectorList: {{ selectors: [{{ text: cssRules[r].selectorText }}] }},
                                            style: {{ cssProperties: [], shorthandEntries: [] }},
                                            origin: sheets[s].href ? "regular" : "user-agent",
                                            sourceURL: sheets[s].href || ""
                                        }},
                                        matchingSelectors: [r]
                                    }};
                                    var decls = cssRules[r].style;
                                    for (var d = 0; d < decls.length; d++) {{
                                        rule.rule.style.cssProperties.push({{
                                            name: decls[d],
                                            value: decls.getPropertyValue(decls[d]),
                                            important: decls.getPropertyPriority(decls[d]) === "important"
                                        }});
                                    }}
                                    rules.push(rule);
                                }}
                            }} catch(e2) {{}}
                        }}
                    }} catch(e1) {{}}
                }}
                var inlineStyle = null;
                if (el.style && el.style.length > 0) {{
                    inlineStyle = {{ cssProperties: [], shorthandEntries: [] }};
                    for (var i = 0; i < el.style.length; i++) {{
                        inlineStyle.cssProperties.push({{
                            name: el.style[i],
                            value: el.style.getPropertyValue(el.style[i]),
                            important: el.style.getPropertyPriority(el.style[i]) === "important"
                        }});
                    }}
                }}
                return JSON.stringify({{"matchedCSSRules": rules, "inlineStyle": inlineStyle, "attributesStyle": null}});
            }} catch(e) {{
                return JSON.stringify({{"matchedCSSRules": [], "inlineStyle": null, "attributesStyle": null}});
            }}
        }})()"#,
        node_ref = node_ref
    );
    let result = page.evaluate_js(&js).map_err(to_browser_error)?;
    parse_js_result(&result)
}

fn cmd_css_get_inline_styles(page: &PageHandle, node_id: i64) -> Result<Value, String> {
    let node_ref = resolve_node_by_id(page, node_id)?;
    let js = format!(
        r#"(function() {{
            var el = {node_ref};
            if (!el || !el.nodeType || el.nodeType !== 1) return JSON.stringify({{"inlineStyle": null}});
            try {{
                var inlineStyle = null;
                if (el.style && el.style.length > 0) {{
                    inlineStyle = {{ cssProperties: [], shorthandEntries: [] }};
                    for (var i = 0; i < el.style.length; i++) {{
                        inlineStyle.cssProperties.push({{
                            name: el.style[i],
                            value: el.style.getPropertyValue(el.style[i]),
                            important: el.style.getPropertyPriority(el.style[i]) === "important"
                        }});
                    }}
                }}
                var attributesStyle = null;
                if (el.getAttribute('style')) {{
                    attributesStyle = {{ cssProperties: [], shorthandEntries: [] }};
                    var styleText = el.getAttribute('style');
                    var pairs = styleText.split(';');
                    for (var p = 0; p < pairs.length; p++) {{
                        var kv = pairs[p].trim();
                        if (kv) {{
                            var colon = kv.indexOf(':');
                            if (colon > 0) {{
                                var name = kv.substring(0, colon).trim();
                                var value = kv.substring(colon + 1).trim();
                                var important = value.endsWith(' !important');
                                if (important) value = value.substring(0, value.length - 11).trim();
                                attributesStyle.cssProperties.push({{
                                    name: name, value: value, important: important
                                }});
                            }}
                        }}
                    }}
                }}
                return JSON.stringify({{"inlineStyle": inlineStyle, "attributesStyle": attributesStyle}});
            }} catch(e) {{
                return JSON.stringify({{"inlineStyle": null}});
            }}
        }})()"#,
        node_ref = node_ref
    );
    let result = page.evaluate_js(&js).map_err(to_browser_error)?;
    parse_js_result(&result)
}

// ---------------------------------------------------------------------------
// Runtime domain commands — JS evaluate for object inspection and function calls
// ---------------------------------------------------------------------------

/// JS prelude that installs the page-realm object registry backing the CDP
/// Runtime object protocol (evaluate-handle / callFunctionOn / getProperties /
/// releaseObject). Idempotent — a second run is a no-op.
///
/// The registry IS the CDP object reference table: every RemoteObject objectId
/// pins a strong reference until `Runtime.releaseObject`/`releaseObjectGroup`
/// drops it, which is what keeps handed-out objects GC-alive across
/// evaluations. DEVIATION (documented): Chrome keeps this table debugger-side;
/// the servo embedder exposes no JSObject egress through the evaluate bridge,
/// so the strong refs live in a page-realm `Object.create(null)` map and the
/// table is page-visible (acceptable for an automation-facing CDP face).
const CDP_REGISTRY_PRELUDE: &str = r#"(function() {
  if (window.__bao_cdp) return 'ok';
  var objs = Object.create(null);
  var seq = 0;
  function alloc(v, group) {
    seq++;
    var oid = 'obj-' + seq + '-' + Math.floor(Math.random() * 1e9).toString(36);
    objs[oid] = { v: v, g: group || '' };
    return oid;
  }
  function get(oid) { return (oid in objs) ? objs[oid].v : undefined; }
  function release(oid) { delete objs[oid]; }
  function releaseGroup(g) { for (var k in objs) { if (objs[k].g === g) delete objs[k]; } }
  function wrap(v, byValue, group) {
    var ro;
    if (v === null) {
      ro = { type: 'object', subtype: 'null', description: 'null' };
    } else if (v === undefined) {
      ro = { type: 'undefined' };
    } else {
      var t = typeof v;
      if (t === 'number') {
        var us = null;
        if (v !== v) us = 'NaN';
        else if (v === Infinity) us = 'Infinity';
        else if (v === -Infinity) us = '-Infinity';
        else if (v === 0 && 1 / v < 0) us = '-0';
        ro = us
          ? { type: 'number', unserializableValue: us, description: us }
          : { type: 'number', value: v, description: String(v) };
      } else if (t === 'string') {
        ro = { type: 'string', value: v };
      } else if (t === 'boolean') {
        ro = { type: 'boolean', value: v };
      } else if (t === 'bigint') {
        ro = { type: 'bigint', unserializableValue: String(v), description: String(v) + 'n' };
      } else if (t === 'symbol') {
        ro = { type: 'symbol', description: String(v) };
      } else if (t === 'function') {
        ro = { type: 'function', className: 'Function', description: (v.name ? 'function ' + v.name + '()' : 'function ()'), objectId: alloc(v, group) };
      } else {
        var sub;
        if (Array.isArray(v)) sub = 'array';
        else if (v instanceof Date) sub = 'date';
        else if (v instanceof RegExp) sub = 'regexp';
        else if (v instanceof Error) sub = 'error';
        else if (v === window) sub = 'window';
        else if (typeof Node !== 'undefined' && v instanceof Node) sub = 'node';
        var desc;
        if (sub === 'array') desc = 'Array(' + v.length + ')';
        else if (sub === 'date') desc = String(v);
        else if (sub === 'regexp') desc = String(v);
        else if (sub === 'error') desc = ((v.constructor && v.constructor.name) ? (v.constructor.name + ': ') : '') + (v.message || '');
        else if (sub === 'node') { try { desc = v.nodeName.toLowerCase() + (v.id ? '#' + v.id : ''); } catch (e2) { desc = String(v.nodeName); } }
        else { try { desc = String(v); } catch (e2) { desc = 'Object'; } }
        var cn = 'Object';
        try { if (v.constructor && v.constructor.name) cn = v.constructor.name; } catch (e2) {}
        ro = { type: 'object', className: cn, description: desc, objectId: alloc(v, group) };
        if (sub) ro.subtype = sub;
      }
    }
    if (byValue && v !== null && v !== undefined && (typeof v === 'object' || typeof v === 'function')) {
      try { ro.value = v; } catch (e) {}
    }
    return ro;
  }
  window.__bao_cdp = { alloc: alloc, get: get, release: release, releaseGroup: releaseGroup, wrap: wrap };
  return 'ok';
})()"#;

/// Resolve a CDP objectId to a JS expression that references the object.
/// objectId formats:
/// "node-N" → DOM node reference (legacy DOM-domain mapping)
/// "obj-*"  → page-realm registry entry (CDP_REGISTRY_PRELUDE table)
fn resolve_object_by_id(object_id: &str) -> String {
    if object_id.starts_with("node-") {
        let idx: i64 = object_id[5..].parse().unwrap_or(0);
        match idx {
            0 | 1 => "document".to_string(),
            2 => "document.documentElement".to_string(),
            _ => format!("document.body.childNodes[{}]", idx - 3),
        }
    } else {
        format!(
            "window.__bao_cdp.get({})",
            serde_json::to_string(object_id).unwrap_or_default()
        )
    }
}

fn cmd_runtime_get_properties(
    page: &PageHandle,
    object_id: &str,
    own_properties: Option<bool>,
) -> Result<Value, String> {
    page.evaluate_js_web(CDP_REGISTRY_PRELUDE)
        .map_err(to_browser_error)?;
    let obj_ref = resolve_object_by_id(object_id);
    let own = own_properties.unwrap_or(true);
    // Property enumeration: own=true → getOwnPropertyNames (own properties,
    // data + accessors); own=false → for-in (own + inherited enumerables).
    // Every property value becomes a real RemoteObject — object/function
    // values are registered in the page registry, so the returned objectIds
    // roundtrip through callFunctionOn/getProperties (the previous code
    // fabricated ids it never stored, and resolving them always gave null).
    // Web-scope evaluation per REQ-SEC-002/003 (registry is page-realm).
    let js = format!(
        r#"(function() {{
            try {{
                var obj = {obj_ref};
                if (obj === null || obj === undefined) return JSON.stringify({{ "result": [] }});
                var names;
                if ({own}) {{
                    names = Object.getOwnPropertyNames(obj);
                }} else {{
                    names = [];
                    for (var n in obj) names.push(n);
                }}
                var result = [];
                for (var i = 0; i < names.length; i++) {{
                    var name = names[i];
                    try {{
                        var desc = Object.getOwnPropertyDescriptor(obj, name);
                        if (!desc) continue;
                        var entry = {{ name: name, configurable: !!desc.configurable, enumerable: !!desc.enumerable, isOwn: {own} }};
                        if ('value' in desc) {{
                            entry.value = window.__bao_cdp.wrap(desc.value, false, '');
                            entry.writable = !!desc.writable;
                        }} else {{
                            if (desc.get) entry.get = window.__bao_cdp.wrap(desc.get, false, '');
                            if (desc.set) entry.set = window.__bao_cdp.wrap(desc.set, false, '');
                        }}
                        result.push(entry);
                    }} catch (e2) {{
                        result.push({{ name: name, value: {{ type: 'undefined' }}, configurable: false, enumerable: false }});
                    }}
                }}
                return JSON.stringify({{ "result": result }});
            }} catch (e) {{
                return JSON.stringify({{ "result": [] }});
            }}
        }})()"#,
        obj_ref = obj_ref,
        own = own,
    );
    let result = page.evaluate_js_web(&js).map_err(to_browser_error)?;
    parse_js_result(&result)
}

/// Materialize one CDP CallArgument as a JS expression: `{value}` (JSON
/// literal), `{unserializableValue}` (NaN/±Infinity/-0/BigInt) or `{objectId}`
/// resolved through the page-realm registry (or the DOM node mapping).
fn call_argument_expr(arg: &Value) -> Result<String, String> {
    let Some(obj) = arg.as_object() else {
        return Err("callFunctionOn arguments entries must be CallArgument objects".into());
    };
    if let Some(v) = obj.get("value") {
        return Ok(serde_json::to_string(v).unwrap_or_else(|_| "undefined".into()));
    }
    if let Some(us) = obj.get("unserializableValue").and_then(|v| v.as_str()) {
        return match us {
            "NaN" | "Infinity" | "-Infinity" | "-0" => Ok(us.to_string()),
            _ if us.ends_with('n') && us.len() >= 2 => {
                let digits = us[..us.len() - 1]
                    .strip_prefix('-')
                    .unwrap_or(&us[..us.len() - 1]);
                if !digits.is_empty() && digits.chars().all(|c| c.is_ascii_digit()) {
                    // BigInt literal ("123n" / "-5n")
                    Ok(us.to_string())
                } else {
                    Err(format!("unsupported unserializableValue: {us}"))
                }
            }
            _ => Err(format!("unsupported unserializableValue: {us}")),
        };
    }
    if let Some(oid) = obj.get("objectId").and_then(|v| v.as_str()) {
        return Ok(resolve_object_by_id(oid));
    }
    Ok("undefined".to_string())
}

fn cmd_runtime_call_function_on(
    page: &PageHandle,
    object_id: Option<&str>,
    execution_context_id: Option<i64>,
    function_declaration: &str,
    arguments: Option<&Value>,
    return_by_value: Option<bool>,
    await_promise: Option<bool>,
    object_group: Option<&str>,
) -> Result<Value, String> {
    // The page realm's security contract (REQ-SEC-002/003): page-facing CDP
    // evaluation runs web-scope — evaluate_js_web, never the Node-realm
    // privileged face. The registry must exist before any object reference
    // is resolved; installing is idempotent.
    page.evaluate_js_web(CDP_REGISTRY_PRELUDE)
        .map_err(to_browser_error)?;

    // `this` for the call: objectId wins. executionContextId alone means
    // this=undefined (single page-realm context — DEVIATION: the servo
    // embedder exposes no isolated worlds, so all context ids evaluate
    // against the page realm).
    let _ctx = execution_context_id; // single-realm: routing is the page itself
    let this_expr = match object_id {
        Some(oid) => resolve_object_by_id(oid),
        None => "undefined".to_string(),
    };

    // CDP CallArgument materialization ({value} / {unserializableValue} /
    // {objectId}).
    let mut args_js = String::from("[");
    if let Some(Value::Array(arr)) = arguments {
        let parts: Vec<String> = arr
            .iter()
            .map(call_argument_expr)
            .collect::<Result<_, _>>()?;
        args_js.push_str(&parts.join(", "));
    } else if let Some(other) = arguments {
        return Err(format!(
            "callFunctionOn arguments must be an array, got: {other:.200}"
        ));
    }
    args_js.push(']');

    let rbv = return_by_value.unwrap_or(false);
    let await_js = await_promise.unwrap_or(false);
    let group_json =
        serde_json::to_string(object_group.unwrap_or("")).unwrap_or_else(|_| "\"..\"".into());
    let func_json = serde_json::to_string(function_declaration).unwrap_or_default();

    // functionDeclaration is a stringized function ("function(a, b) { ... }");
    // it is called with the materialized arguments on the resolved `this`.
    let js = format!(
        r#"(function() {{
            try {{
                var fn = Function('return (' + {func_json} + ')')();
                if (typeof fn !== 'function') {{
                    return JSON.stringify({{ result: {{ type: 'undefined' }}, exceptionDetails: {{ text: 'functionDeclaration did not evaluate to a function', exceptionId: 0 }} }});
                }}
                var r = fn.apply({this_expr}, {args_js});
                if ({await_js} && r !== null && typeof r === 'object' && typeof r.then === 'function') {{
                    window.__bao_async = {{ state: 'pending' }};
                    Promise.resolve(r).then(
                        function(v) {{ window.__bao_async = {{ state: 'ok', v: v }}; }},
                        function(e) {{ window.__bao_async = {{ state: 'err', e: e }}; }}
                    );
                    return JSON.stringify({{ __baoAsync: true }});
                }}
                return JSON.stringify({{ result: window.__bao_cdp.wrap(r, {rbv}, {group_json}), exceptionDetails: null }});
            }} catch (e) {{
                var exObj = (e !== null && typeof e === 'object') ? window.__bao_cdp.wrap(e, false, {group_json}) : undefined;
                return JSON.stringify({{ result: {{ type: 'undefined' }}, exceptionDetails: {{ text: String((e && e.message) || e), exception: exObj, exceptionId: 0 }} }});
            }}
        }})()"#,
        this_expr = this_expr,
        args_js = args_js,
        func_json = func_json,
        rbv = rbv,
        await_js = await_js,
        group_json = group_json,
    );
    let result = page.evaluate_js_web(&js).map_err(to_browser_error)?;
    // The wrapper always returns JSON.stringify({result/exceptionDetails}) —
    // an unparseable output is a real failure, never a silent {}.
    let parsed: Value = serde_json::from_str(&result).map_err(|e| {
        format!("Runtime.callFunctionOn: page did not return the wrapper JSON: {e} (got: {result:.200})")
    })?;
    if parsed.get("__baoAsync").and_then(|v| v.as_bool()) == Some(true) {
        return wait_bao_async_promise(page, rbv, &group_json);
    }
    Ok(parsed)
}

/// awaitPromise resolution: the call wrapper parked a pending Promise's
/// continuation in `window.__bao_async`; poll it. Every `evaluate_js_web`
/// spins the servo event loop itself, so microtask/timer/fetch chains keep
/// making progress between polls. Bounded — a never-settling promise
/// surfaces as an error instead of hanging the bridge worker.
fn wait_bao_async_promise(
    page: &PageHandle,
    return_by_value: bool,
    group_json: &str,
) -> Result<Value, String> {
    let poll = format!(
        r#"(function() {{
            var a = window.__bao_async;
            if (!a || a.state === 'pending') return JSON.stringify({{ pending: true }});
            if (a.state === 'ok') return JSON.stringify({{ result: window.__bao_cdp.wrap(a.v, {rbv}, {group_json}), exceptionDetails: null }});
            var exObj = (a.e !== null && typeof a.e === 'object') ? window.__bao_cdp.wrap(a.e, false, {group_json}) : undefined;
            return JSON.stringify({{ result: {{ type: 'undefined' }}, exceptionDetails: {{ text: String((a.e && a.e.message) || a.e), exception: exObj, exceptionId: 0 }} }});
        }})()"#,
        rbv = return_by_value,
        group_json = group_json,
    );
    let deadline = std::time::Instant::now() + std::time::Duration::from_secs(20);
    loop {
        let out = page.evaluate_js_web(&poll).map_err(to_browser_error)?;
        let parsed: Value = serde_json::from_str(&out).map_err(|e| {
            format!("Runtime.callFunctionOn: async poll wrapper unparseable: {e} (got: {out:.200})")
        })?;
        if parsed.get("pending").and_then(|v| v.as_bool()) != Some(true) {
            return Ok(parsed);
        }
        if std::time::Instant::now() >= deadline {
            return Err(
                "Runtime.callFunctionOn: awaitPromise did not settle within 20s".into(),
            );
        }
        std::thread::sleep(std::time::Duration::from_millis(10));
    }
}

/// Runtime.releaseObject — drop one registry entry (frees the strong ref the
/// handed-out objectId pinned; guards against evaluateHandle leak loops).
fn cmd_runtime_release_object(page: &PageHandle, object_id: &str) -> Result<Value, String> {
    let oid_json = serde_json::to_string(object_id).unwrap_or_default();
    let js = format!(
        r#"(function() {{ if (window.__bao_cdp) window.__bao_cdp.release({oid_json}); return 'ok'; }})()"#
    );
    page.evaluate_js_web(&js).map_err(to_browser_error)?;
    Ok(serde_json::json!({}))
}

/// Runtime.releaseObjectGroup — drop every registry entry minted under the
/// objectGroup (Playwright releases its "utility"/"console" groups on
/// context teardown with exactly this call).
fn cmd_runtime_release_object_group(
    page: &PageHandle,
    object_group: &str,
) -> Result<Value, String> {
    let group_json = serde_json::to_string(object_group).unwrap_or_default();
    let js = format!(
        r#"(function() {{ if (window.__bao_cdp) window.__bao_cdp.releaseGroup({group_json}); return 'ok'; }})()"#
    );
    page.evaluate_js_web(&js).map_err(to_browser_error)?;
    Ok(serde_json::json!({}))
}

fn json_type(v: &Value) -> &'static str {
    match v {
        Value::Null => "undefined",
        Value::Bool(_) => "boolean",
        Value::Number(_) => "number",
        Value::String(_) => "string",
        Value::Array(_) => "object",
        Value::Object(_) => "object",
    }
}

/// Parse a JS evaluate_js string result into a serde_json::Value.
fn parse_js_result(result: &str) -> Result<Value, String> {
    // Fail-closed: an unparseable wrapper output is a real failure, never a
    // silent {}. (The previous `.unwrap_or(Ok(json!({})))` had a type-level
    // bug — serde deserialized into an externally-tagged Result<Value,String>
    // envelope, which never matches normal JSON, so EVERY caller silently
    // got {} back. BCE: silent-fallback masquerading as delivery.)
    serde_json::from_str(result)
        .map_err(|e| format!("unparseable JS wrapper output: {e} (got: {result:.200})"))
}

fn json_type_string(s: &str) -> &'static str {
    if s.is_empty() || s == "undefined" {
        "undefined"
    } else if s == "null" {
        "object"
    } else if s == "true" || s == "false" {
        "boolean"
    } else if s.parse::<f64>().is_ok() {
        "number"
    } else if s.starts_with('{') || s.starts_with('[') {
        "object"
    } else {
        "string"
    }
}

// ─── Network / Cookie / Storage / Security domain handlers ──────────────
// Bridge servo's SiteDataManager and NetworkManager to CDP protocol.

/// Convert a servo `Cookie<'static>` to CDP Cookie JSON object.
/// CDP Cookie spec: https://chromedevtools.github.io/devtools-protocol/tot/Network/#type-Cookie
fn cookie_to_cdp(c: &cookie::Cookie) -> Value {
    let same_site = match c.same_site() {
        Some(cookie::SameSite::Strict) => "Strict",
        Some(cookie::SameSite::Lax) => "Lax",
        Some(cookie::SameSite::None) => "None",
        None => "None",
    };
    let expires = c
        .expires_datetime()
        .map(|dt| dt.unix_timestamp() as f64)
        .unwrap_or(-1.0);
    serde_json::json!({
        "name": c.name(),
        "value": c.value(),
        "domain": c.domain().unwrap_or(""),
        "path": c.path().unwrap_or("/"),
        "expires": expires,
        "size": c.name().len() + c.value().len(),
        "httpOnly": c.http_only().unwrap_or(false),
        "secure": c.secure().unwrap_or(false),
        "sameSite": same_site,
        "session": expires == -1.0,
    })
}

/// Build a `cookie::Cookie<'static>` from CDP setCookie parameters.
fn cdp_params_to_cookie(
    name: &str,
    value: &str,
    _url: Option<&str>,
    domain: Option<&str>,
) -> cookie::Cookie<'static> {
    let mut builder = cookie::Cookie::build((name.to_string(), value.to_string()));
    if let Some(d) = domain {
        if d.starts_with('.') {
            builder = builder.domain(d.to_string());
        } else {
            builder = builder.domain(format!(".{d}"));
        }
    }
    builder = builder.path("/");
    builder.build()
}

/// Network.getCookies — retrieve cookies for the given URLs (or current page URL).
fn cmd_get_cookies(page: &PageHandle, urls: &[String]) -> Result<Value, String> {
    let servo = page.servo();
    let sdm = servo.site_data_manager();
    let cookies: Vec<Value> = if urls.is_empty() {
        // No URLs specified — use the current page URL
        let current_url = page.current_url().unwrap_or_default();
        if current_url.is_empty() || current_url == "about:blank" {
            Vec::new()
        } else {
            match url::Url::parse(&current_url) {
                Ok(parsed) => {
                    let servo_cookies = sdm.cookies_for_url(parsed, CookieSource::HTTP);
                    servo_cookies.iter().map(cookie_to_cdp).collect()
                }
                Err(_) => Vec::new(),
            }
        }
    } else {
        // Collect cookies for each URL, deduplicating by (name, domain, path)
        let mut seen = HashSet::new();
        let mut result = Vec::new();
        for url_str in urls {
            if let Ok(parsed) = url::Url::parse(url_str) {
                for c in sdm.cookies_for_url(parsed, CookieSource::HTTP) {
                    let key = (
                        c.name().to_string(),
                        c.domain().unwrap_or("").to_string(),
                        c.path().unwrap_or("").to_string(),
                    );
                    if seen.insert(key) {
                        result.push(cookie_to_cdp(&c));
                    }
                }
            }
        }
        result
    };
    Ok(serde_json::json!({ "cookies": cookies }))
}

/// Network.getAllCookies — retrieve all cookies from the cookie jar.
fn cmd_get_all_cookies(page: &PageHandle) -> Result<Value, String> {
    let servo = page.servo();
    let sdm = servo.site_data_manager();
    // Get all sites that have cookies, then collect cookies for each
    let site_data = sdm.site_data(StorageType::Cookies);
    let mut cookies: Vec<Value> = Vec::new();
    let mut seen = HashSet::new();
    for sd in site_data {
        let site_name = sd.name();
        // Construct a URL from the site name to query cookies
        let url_str = if site_name.starts_with("http://") || site_name.starts_with("https://") {
            site_name.clone()
        } else {
            format!("https://{site_name}")
        };
        if let Ok(parsed) = url::Url::parse(&url_str) {
            for c in sdm.cookies_for_url(parsed, CookieSource::HTTP) {
                let key = (
                    c.name().to_string(),
                    c.domain().unwrap_or("").to_string(),
                    c.path().unwrap_or("").to_string(),
                );
                if seen.insert(key) {
                    cookies.push(cookie_to_cdp(&c));
                }
            }
        }
    }
    Ok(serde_json::json!({ "cookies": cookies }))
}

/// Network.setCookie — set a cookie via servo's SiteDataManager.
fn cmd_set_cookie(
    page: &PageHandle,
    name: &str,
    value: &str,
    url: Option<&str>,
    domain: Option<&str>,
) -> Result<Value, String> {
    let servo = page.servo();
    let sdm = servo.site_data_manager();
    let cookie = cdp_params_to_cookie(name, value, url, domain);
    // Determine the URL to associate the cookie with
    let fallback_url = page.current_url().unwrap_or_default();
    let url_str = url.unwrap_or_else(|| {
        if fallback_url.is_empty() || fallback_url == "about:blank" {
            "https://localhost/"
        } else {
            fallback_url.as_str()
        }
    });
    let parsed = url::Url::parse(url_str).map_err(|e| format!("invalid URL for setCookie: {e}"))?;
    sdm.set_cookie_for_url(parsed, cookie, None);
    Ok(serde_json::json!({ "success": true }))
}

/// Network.deleteCookies — delete cookies matching name (and optionally url/domain).
fn cmd_delete_cookie(page: &PageHandle, name: &str, url: Option<&str>) -> Result<Value, String> {
    let servo = page.servo();
    let sdm = servo.site_data_manager();
    if let Some(url_str) = url {
        let parsed =
            url::Url::parse(url_str).map_err(|e| format!("invalid URL for deleteCookies: {e}"))?;
        // Get current cookies for this URL
        let current = sdm.cookies_for_url(parsed.clone(), CookieSource::HTTP);
        // Clear all cookies for this site, then re-set the ones that don't match the name
        let site = parsed.host_str().unwrap_or("");
        sdm.clear_site_data(&[site], StorageType::Cookies);
        // Re-set cookies that don't match the name to delete
        for c in current {
            if c.name() != name {
                sdm.set_cookie_for_url(parsed.clone(), c, None);
            }
        }
    } else {
        // No URL — clear cookies for all sites matching the name
        let site_data = sdm.site_data(StorageType::Cookies);
        for sd in site_data {
            let site_name = sd.name();
            let url_str = if site_name.starts_with("http://") || site_name.starts_with("https://") {
                site_name.clone()
            } else {
                format!("https://{site_name}")
            };
            if let Ok(parsed) = url::Url::parse(&url_str) {
                let current = sdm.cookies_for_url(parsed.clone(), CookieSource::HTTP);
                let has_match = current.iter().any(|c| c.name() == name);
                if has_match {
                    sdm.clear_site_data(&[&site_name], StorageType::Cookies);
                    for c in current {
                        if c.name() != name {
                            sdm.set_cookie_for_url(parsed.clone(), c, None);
                        }
                    }
                }
            }
        }
    }
    Ok(serde_json::json!({}))
}

/// Network.setCacheDisabled — clear cache when cache_disabled is true.
fn cmd_network_set_cache_disabled(
    page: &PageHandle,
    cache_disabled: bool,
) -> Result<Value, String> {
    if cache_disabled {
        let servo = page.servo();
        let nm = servo.network_manager();
        nm.clear_cache();
    }
    Ok(serde_json::json!({}))
}

/// Network.clearBrowserCache — clear the HTTP cache via servo's NetworkManager.
fn cmd_network_clear_browser_cache(page: &PageHandle) -> Result<Value, String> {
    let servo = page.servo();
    let nm = servo.network_manager();
    nm.clear_cache();
    Ok(serde_json::json!({}))
}

/// Network.clearBrowserCookies — clear all cookies via servo's SiteDataManager.
fn cmd_network_clear_browser_cookies(page: &PageHandle) -> Result<Value, String> {
    let servo = page.servo();
    let sdm = servo.site_data_manager();
    sdm.clear_cookies(None);
    Ok(serde_json::json!({}))
}

/// Storage.getStorageItemsForOrigin — list storage data for an origin.
fn cmd_storage_get_items(
    page: &PageHandle,
    origin: String,
    storage_type: String,
) -> Result<Value, String> {
    let servo = page.servo();
    let sdm = servo.site_data_manager();
    let st = parse_storage_type(&storage_type);
    let site_data = sdm.site_data(st);
    let items: Vec<Value> = site_data
        .iter()
        .filter(|sd| {
            let site_name = sd.name();
            origin.is_empty()
                || site_name == origin
                || site_name.ends_with(&format!(".{origin}"))
                || origin.ends_with(&format!(".{site_name}"))
        })
        .map(|sd| {
            serde_json::json!({
                "origin": sd.name(),
                "storageType": storage_type,
            })
        })
        .collect();
    Ok(serde_json::json!({ "storageItems": items }))
}

/// Storage.clearDataForOrigin — clear storage data for a specific origin.
fn cmd_storage_clear_data(
    page: &PageHandle,
    origin: String,
    storage_type: String,
) -> Result<Value, String> {
    let servo = page.servo();
    let sdm = servo.site_data_manager();
    let st = parse_storage_type(&storage_type);
    if origin.is_empty() {
        sdm.clear_cookies(None);
    } else {
        sdm.clear_site_data(&[&origin], st);
    }
    Ok(serde_json::json!({}))
}

/// Parse CDP storage type string to servo StorageType bitflags.
fn parse_storage_type(storage_type: &str) -> StorageType {
    match storage_type {
        "cookies" | "cookie" => StorageType::Cookies,
        "local_storage" | "local" => StorageType::Local,
        "session_storage" | "session" => StorageType::Session,
        "all" => StorageType::Cookies | StorageType::Local | StorageType::Session,
        _ => StorageType::Cookies | StorageType::Local | StorageType::Session,
    }
}

fn ok_empty() -> Result<Value, String> {
    Ok(serde_json::json!({}))
}

#[cfg(test)]
mod tests {
    use crate::delegate::{ServiceWorkerHandle, ServiceWorkerRegistrationState};
    use serde_json::{json, Value};

    #[test]
    fn json_type_null_returns_undefined() {
        assert_eq!(super::json_type(&json!(null)), "undefined");
    }

    #[test]
    fn json_type_bool_returns_boolean() {
        assert_eq!(super::json_type(&json!(true)), "boolean");
        assert_eq!(super::json_type(&json!(false)), "boolean");
    }

    #[test]
    fn json_type_number_returns_number() {
        assert_eq!(super::json_type(&json!(42)), "number");
        assert_eq!(super::json_type(&json!(3.14)), "number");
        assert_eq!(super::json_type(&json!(0)), "number");
        assert_eq!(super::json_type(&json!(-1)), "number");
    }

    #[test]
    fn json_type_string_returns_string() {
        assert_eq!(super::json_type(&json!("hello")), "string");
        assert_eq!(super::json_type(&json!("")), "string");
    }

    #[test]
    fn json_type_array_returns_object() {
        assert_eq!(super::json_type(&json!([1, 2, 3])), "object");
        assert_eq!(super::json_type(&json!([])), "object");
    }

    #[test]
    fn json_type_object_returns_object() {
        assert_eq!(super::json_type(&json!({"a": 1})), "object");
        assert_eq!(super::json_type(&json!({})), "object");
    }

    #[test]
    fn json_type_string_empty_returns_undefined() {
        assert_eq!(super::json_type_string(""), "undefined");
    }

    #[test]
    fn json_type_string_undefined_returns_undefined() {
        assert_eq!(super::json_type_string("undefined"), "undefined");
    }

    #[test]
    fn json_type_string_null_returns_object() {
        assert_eq!(super::json_type_string("null"), "object");
    }

    #[test]
    fn json_type_string_true_returns_boolean() {
        assert_eq!(super::json_type_string("true"), "boolean");
    }

    #[test]
    fn json_type_string_false_returns_boolean() {
        assert_eq!(super::json_type_string("false"), "boolean");
    }

    #[test]
    fn json_type_string_integer_returns_number() {
        assert_eq!(super::json_type_string("42"), "number");
        assert_eq!(super::json_type_string("0"), "number");
        assert_eq!(super::json_type_string("-7"), "number");
    }

    #[test]
    fn json_type_string_float_returns_number() {
        assert_eq!(super::json_type_string("3.14"), "number");
        assert_eq!(super::json_type_string("-0.5"), "number");
    }

    #[test]
    fn json_type_string_object_brace_returns_object() {
        assert_eq!(super::json_type_string("{\"a\":1}"), "object");
    }

    #[test]
    fn json_type_string_array_bracket_returns_object() {
        assert_eq!(super::json_type_string("[1,2,3]"), "object");
    }

    #[test]
    fn json_type_string_regular_text_returns_string() {
        assert_eq!(super::json_type_string("hello world"), "string");
        assert_eq!(super::json_type_string("some result"), "string");
    }

    // ─── json_type edge cases ─────────────────────────────────────
    // @trace REQ-CDP-005 [req:REQ-CDP-005] [level:unit]

    #[test]
    fn json_type_large_number() {
        assert_eq!(super::json_type(&json!(i64::MAX)), "number");
        assert_eq!(super::json_type(&json!(f64::MAX)), "number");
    }

    #[test]
    fn json_type_nested_object() {
        assert_eq!(super::json_type(&json!({"a": {"b": 1}})), "object");
    }

    #[test]
    fn json_type_nested_array() {
        assert_eq!(super::json_type(&json!([[1, 2], [3, 4]])), "object");
    }

    // ─── json_type_string edge cases ──────────────────────────────
    // @trace REQ-CDP-005 [req:REQ-CDP-005] [level:unit]

    #[test]
    fn json_type_string_scientific_notation() {
        assert_eq!(super::json_type_string("1e10"), "number");
        assert_eq!(super::json_type_string("-2.5e-3"), "number");
    }

    #[test]
    fn json_type_string_whitespace_is_string() {
        assert_eq!(super::json_type_string("  "), "string");
        assert_eq!(super::json_type_string(" 42"), "string");
    }

    #[test]
    fn json_type_string_special_strings() {
        // NaN and Infinity parse as f64, so they're "number"
        assert_eq!(super::json_type_string("NaN"), "number");
        assert_eq!(super::json_type_string("Infinity"), "number");
        assert_eq!(super::json_type_string("[object Object]"), "object");
    }

    #[test]
    fn json_type_string_negative_zero() {
        assert_eq!(super::json_type_string("-0"), "number");
        assert_eq!(super::json_type_string("0.0"), "number");
    }

    // ─── to_browser_error edge cases ───────────────────────────────────
    // @trace REQ-CDP-005 [req:REQ-CDP-005] [level:unit]

    #[test]
    fn to_browser_error_init_variant() {
        let err = crate::error::BrowserError::Init("failed to start".into());
        let msg = super::to_browser_error(err);
        assert!(msg.contains("browser init error"));
        assert!(msg.contains("failed to start"));
    }

    #[test]
    fn to_browser_error_navigation_variant() {
        let err = crate::error::BrowserError::Navigation("invalid url".into());
        let msg = super::to_browser_error(err);
        assert!(msg.contains("navigation error"));
        assert!(msg.contains("invalid url"));
    }

    #[test]
    fn to_browser_error_rendering_variant() {
        let err = crate::error::BrowserError::Rendering("gpu lost".into());
        let msg = super::to_browser_error(err);
        assert!(msg.contains("rendering error"));
        assert!(msg.contains("gpu lost"));
    }

    #[test]
    fn to_browser_error_javascript_variant() {
        let err = crate::error::BrowserError::JavaScript("syntax error".into());
        let msg = super::to_browser_error(err);
        assert!(msg.contains("javascript error"));
        assert!(msg.contains("syntax error"));
    }

    #[test]
    fn to_browser_error_cdp_variant() {
        let err = crate::error::BrowserError::CDP("connection refused".into());
        let msg = super::to_browser_error(err);
        assert!(msg.contains("cdp error"));
        assert!(msg.contains("connection refused"));
    }

    #[test]
    fn to_browser_error_empty_message() {
        let err = crate::error::BrowserError::Init(String::new());
        let msg = super::to_browser_error(err);
        assert!(msg.contains("browser init error"));
    }

    #[test]
    fn to_browser_error_unicode_message() {
        let err = crate::error::BrowserError::Navigation("页面加载失败".into());
        let msg = super::to_browser_error(err);
        assert!(msg.contains("页面加载失败"));
    }

    // ─── cmd_navigate/cmd_reload id generation (pure logic) ────────────
    // @trace REQ-CDP-001 [req:REQ-CDP-001] [level:unit]

    #[test]
    fn next_cdp_id_is_unique_and_prefixed() {
        // loaderId/script identifiers are generated from a monotonic counter —
        // never the hardcoded "0"/"1" constants (Chrome semantics: fresh id
        // per load / per added script).
        let a = super::next_cdp_id("loader");
        let b = super::next_cdp_id("loader");
        assert!(a.starts_with("loader-"), "id must carry its prefix: {a}");
        assert_ne!(a, b, "ids must be unique per call");
        let s = super::next_cdp_id("script");
        assert!(s.starts_with("script-"), "id must carry its prefix: {s}");
    }

    #[test]
    fn cmd_navigate_uses_page_id_frame_and_generated_loader() {
        // frameId = real page id (stable across navigations), loaderId =
        // generated per load — no hardcoded "0" constants remain.
        let source = include_str!("cdp_handler.rs");
        assert!(
            source.contains("\"frameId\": page.id().to_string()"),
            "cmd_navigate/cmd_reload must return the real page id as frameId"
        );
        assert!(
            source.contains("\"loaderId\": next_cdp_id(\"loader\")"),
            "cmd_navigate/cmd_reload must generate a fresh loaderId per load"
        );
        assert!(
            !source.contains("\"loaderId\": \"0\""),
            "no canned loaderId \"0\" may remain"
        );
    }

    // ─── cmd_evaluate response structure (pure logic) ──────────────────
    // @trace REQ-CDP-001 [req:REQ-CDP-001] [level:unit]

    #[test]
    fn cmd_evaluate_return_by_value_true_json_parse() {
        // When return_by_value is true and result is valid JSON, it's parsed
        let result_str = r#"{"a":1}"#;
        let parsed: Result<Value, _> = serde_json::from_str(result_str);
        assert!(parsed.is_ok());
        assert_eq!(super::json_type(&parsed.unwrap()), "object");
    }

    #[test]
    fn cmd_evaluate_return_by_value_true_non_json_falls_back() {
        // When return_by_value is true but result is not valid JSON, falls back to json_type_string
        let result_str = "hello world";
        let parsed: Result<Value, _> = serde_json::from_str(result_str);
        assert!(parsed.is_err());
        assert_eq!(super::json_type_string(result_str), "string");
    }

    #[test]
    fn cmd_evaluate_return_by_value_true_null_json() {
        let parsed: Result<Value, _> = serde_json::from_str("null");
        assert!(parsed.is_ok());
        assert_eq!(super::json_type(&parsed.unwrap()), "undefined");
    }

    #[test]
    fn cmd_evaluate_return_by_value_true_number_json() {
        let parsed: Result<Value, _> = serde_json::from_str("42");
        assert!(parsed.is_ok());
        assert_eq!(super::json_type(&parsed.unwrap()), "number");
    }

    #[test]
    fn cmd_evaluate_return_by_value_true_boolean_json() {
        let parsed: Result<Value, _> = serde_json::from_str("true");
        assert!(parsed.is_ok());
        assert_eq!(super::json_type(&parsed.unwrap()), "boolean");
    }

    #[test]
    fn cmd_evaluate_return_by_value_false_uses_description() {
        // When return_by_value is false, result uses json_type_string for type
        let result_str = "some JS output";
        assert_eq!(super::json_type_string(result_str), "string");
    }

    // ─── cmd_screenshot format mapping (pure logic) ────────────────────
    // @trace REQ-CDP-007 [req:REQ-CDP-007] [level:unit]

    #[test]
    fn cmd_screenshot_format_jpeg_mapping() {
        // "jpeg" -> ScreenshotFormat::Jpeg, anything else -> Png
        let fmt = match "jpeg" {
            "jpeg" => "Jpeg",
            _ => "Png",
        };
        assert_eq!(fmt, "Jpeg");
    }

    #[test]
    fn cmd_screenshot_format_png_mapping() {
        let fmt = match "png" {
            "jpeg" => "Jpeg",
            _ => "Png",
        };
        assert_eq!(fmt, "Png");
    }

    #[test]
    fn cmd_screenshot_format_unknown_defaults_to_png() {
        let fmt = match "bmp" {
            "jpeg" => "Jpeg",
            "webp" => "WebP",
            _ => "Png",
        };
        assert_eq!(fmt, "Png");
    }

    #[test]
    fn cmd_screenshot_format_webp_mapping() {
        let fmt = match "webp" {
            "jpeg" => "Jpeg",
            "webp" => "WebP",
            _ => "Png",
        };
        assert_eq!(fmt, "WebP");
    }

    #[test]
    fn cmd_screenshot_format_empty_defaults_to_png() {
        let fmt = match "" {
            "jpeg" => "Jpeg",
            _ => "Png",
        };
        assert_eq!(fmt, "Png");
    }

    #[test]
    fn cmd_screenshot_base64_encoding() {
        // Verify base64 encoding produces valid output
        let bytes: Vec<u8> = vec![0x89, 0x50, 0x4E, 0x47]; // PNG magic bytes
        let b64 = base64::Engine::encode(&base64::engine::general_purpose::STANDARD, &bytes);
        assert!(!b64.is_empty());
        // Base64 should be decodable back
        let decoded = base64::Engine::decode(&base64::engine::general_purpose::STANDARD, &b64);
        assert!(decoded.is_ok());
        assert_eq!(decoded.unwrap(), bytes);
    }

    #[test]
    fn cmd_screenshot_base64_empty_bytes() {
        let bytes: Vec<u8> = vec![];
        let b64 = base64::Engine::encode(&base64::engine::general_purpose::STANDARD, &bytes);
        assert_eq!(b64, ""); // empty input -> empty base64
    }

    // ─── cmd_query_selector JS construction (pure logic) ────────────────
    // @trace REQ-CDP-001 [req:REQ-CDP-001] [level:unit]

    #[test]
    fn cmd_query_selector_js_construction_valid_selector() {
        let selector = "div.main";
        let js = format!(
            "(function() {{ var e = document.querySelector({}); return e ? 1 : 0; }})()",
            serde_json::to_string(selector).unwrap_or_default()
        );
        assert!(js.contains("document.querySelector"));
        assert!(js.contains("\"div.main\""));
    }

    #[test]
    fn cmd_query_selector_js_construction_empty_selector() {
        let selector = "";
        let json_str = serde_json::to_string(selector).unwrap_or_default();
        assert_eq!(json_str, "\"\"");
    }

    #[test]
    fn cmd_query_selector_js_construction_special_chars() {
        let selector = "div[data-attr='value']";
        let json_str = serde_json::to_string(selector).unwrap_or_default();
        // serde_json should escape the single quotes properly
        assert!(json_str.contains("div[data-attr"));
    }

    #[test]
    fn cmd_query_selector_js_construction_unicode() {
        let selector = "div.中文类名";
        let json_str = serde_json::to_string(selector).unwrap_or_default();
        assert!(json_str.contains("中文类名"));
    }

    // ─── cmd_query_selector_all JS construction (pure logic) ────────────
    // @trace REQ-CDP-001 [req:REQ-CDP-001] [level:unit]

    #[test]
    fn cmd_query_selector_all_js_construction() {
        let selector = "li.item";
        let js = format!(
            "(function() {{ return document.querySelectorAll({}).length; }})()",
            serde_json::to_string(selector).unwrap_or_default()
        );
        assert!(js.contains("document.querySelectorAll"));
        assert!(js.contains(".length"));
    }

    #[test]
    fn cmd_query_selector_all_count_to_node_ids() {
        // When count is 3, nodeIds should be [1, 2, 3]
        let count: i64 = 3;
        let ids: Vec<i64> = (1..=count).collect();
        assert_eq!(ids, vec![1, 2, 3]);
    }

    #[test]
    fn cmd_query_selector_all_zero_count() {
        let count: i64 = 0;
        let ids: Vec<i64> = (1..=count).collect();
        assert!(ids.is_empty());
    }

    #[test]
    fn cmd_query_selector_all_large_count() {
        let count: i64 = 100;
        let ids: Vec<i64> = (1..=count).collect();
        assert_eq!(ids.len(), 100);
        assert_eq!(ids[0], 1);
        assert_eq!(ids[99], 100);
    }

    // ─── cmd_set_attribute JS construction (pure logic) ─────────────────
    // @trace REQ-CDP-001 [req:REQ-CDP-001] [level:unit]

    #[test]
    fn cmd_set_attribute_js_construction() {
        let name = "class";
        let value = "active";
        let js = format!(
            "(function() {{ document.querySelector('[data-cdp]')?.setAttribute({}, {}); }})()",
            serde_json::to_string(name).unwrap_or_default(),
            serde_json::to_string(value).unwrap_or_default(),
        );
        assert!(js.contains("setAttribute"));
        assert!(js.contains("\"class\""));
        assert!(js.contains("\"active\""));
    }

    #[test]
    fn cmd_set_attribute_js_with_quotes_in_value() {
        let name = "data-info";
        let value = r#"he said "hello""#;
        let _json_name = serde_json::to_string(name).unwrap_or_default();
        let json_value = serde_json::to_string(value).unwrap_or_default();
        // The double quotes should be escaped in JSON
        assert!(json_value.contains("\\\""));
    }

    // ─── cmd_insert_text JS construction (pure logic) ──────────────────
    // @trace REQ-CDP-001 [req:REQ-CDP-001] [level:unit]

    #[test]
    fn cmd_insert_text_js_construction() {
        let text = "hello";
        let js = format!(
            "(function() {{ var el = document.activeElement; if (el && 'value' in el) el.value += {}; }})()",
            serde_json::to_string(text).unwrap_or_default(),
        );
        assert!(js.contains("document.activeElement"));
        assert!(js.contains("el.value"));
    }

    #[test]
    fn cmd_insert_text_js_empty_string() {
        let text = "";
        let json_str = serde_json::to_string(text).unwrap_or_default();
        assert_eq!(json_str, "\"\"");
    }

    #[test]
    fn cmd_insert_text_js_newline_escaped() {
        let text = "line1\nline2";
        let json_str = serde_json::to_string(text).unwrap_or_default();
        assert!(json_str.contains("\\n"));
    }

    // ─── cmd_set_user_agent JS construction (pure logic) ───────────────
    // @trace REQ-CDP-001 [req:REQ-CDP-001] [level:unit]

    #[test]
    fn cmd_set_user_agent_js_construction() {
        let ua = "Mozilla/5.0 Test";
        let js = format!(
            "Object.defineProperty(navigator, 'userAgent', {{ get: function() {{ return {}; }} }});",
            serde_json::to_string(ua).unwrap_or_default(),
        );
        assert!(js.contains("Object.defineProperty"));
        assert!(js.contains("navigator"));
        assert!(js.contains("userAgent"));
    }

    #[test]
    fn cmd_set_user_agent_js_empty_string() {
        let ua = "";
        let json_str = serde_json::to_string(ua).unwrap_or_default();
        assert_eq!(json_str, "\"\"");
    }

    // ─── cmd_get_document JS template (pure logic) ─────────────────────
    // @trace REQ-CDP-001 [req:REQ-CDP-001] [level:unit]

    #[test]
    fn cmd_get_document_js_template_structure() {
        let js = r#"
            (function() {
                function walk(node, id) {
                    var result = {
                        nodeId: id,
                        backendNodeId: id,
                        nodeType: node.nodeType,
                        nodeName: node.nodeName,
                        localName: node.localName || '',
                        nodeValue: node.nodeValue || '',
                    };
                    if (node.childNodes && node.childNodes.length > 0) {
                        result.childNodeCount = node.childNodes.length;
                        result.children = [];
                        for (var i = 0; i < Math.min(node.childNodes.length, 20); i++) {
                            result.children.push(walk(node.childNodes[i], id * 100 + i + 1));
                        }
                    }
                    return result;
                }
                return JSON.stringify(walk(document, 1));
            })()
        "#;
        assert!(js.contains("walk"));
        assert!(js.contains("nodeId"));
        assert!(js.contains("nodeType"));
        assert!(js.contains("nodeName"));
        assert!(js.contains("childNodeCount"));
        assert!(js.contains("Math.min"));
        assert!(js.contains("JSON.stringify"));
    }

    #[test]
    fn cmd_get_document_js_limits_children_to_20() {
        // The JS template caps children to 20 via Math.min(node.childNodes.length, 20)
        let _js = r#"(function() { return Math.min(50, 20); })()"#;
        // This is just verifying the logic — 50 children would be capped to 20
        assert_eq!(50usize.min(20), 20);
    }

    // ─── cmd_get_outer_html JS expression (pure logic) ─────────────────
    // @trace REQ-CDP-001 [req:REQ-CDP-001] [level:unit]

    #[test]
    fn cmd_get_outer_html_js_is_simple_expression() {
        let js = "document.documentElement.outerHTML";
        assert!(js.contains("document.documentElement"));
        assert!(js.contains("outerHTML"));
    }

    // ─── cmd_add_script response structure (pure logic) ────────────────
    // @trace REQ-CDP-001 [req:REQ-CDP-001] [level:unit]

    #[test]
    fn cmd_add_script_response_has_generated_identifier() {
        // identifier comes from the monotonic counter — never "1".
        let resp = json!({ "identifier": super::next_cdp_id("script") });
        assert!(resp["identifier"].as_str().unwrap().starts_with("script-"));
    }

    // ─── cmd_reload response structure (pure logic) ────────────────────
    // @trace REQ-CDP-001 [req:REQ-CDP-001] [level:unit]

    #[test]
    fn cmd_reload_response_structure() {
        // cmd_reload uses the real servo reload path (WebView::reload), not a
        // re-navigate of the current URL.
        let source = include_str!("cdp_handler.rs");
        assert!(
            source.contains("page.reload().map_err(to_browser_error)?;"),
            "cmd_reload must call PageHandle::reload"
        );
    }

    // ─── handle_bridge_command wildcard commands (pure logic) ──────────
    // @trace REQ-CDP-001 [req:REQ-CDP-001] [level:unit]

    #[test]
    fn handle_bridge_command_go_back_forward_wired_stop_loading_errors() {
        // GoBack/GoForward dispatch to real servo traversal; StopLoading is an
        // explicit error (servo WebView has no stop-loading API).
        let source = include_str!("cdp_handler.rs");
        assert!(
            source.contains("BridgeCommand::GoBack { target_id } => with_page"),
            "GoBack must be dispatched to a page handler"
        );
        assert!(
            source.contains("BridgeCommand::GoForward { target_id } => with_page"),
            "GoForward must be dispatched to a page handler"
        );
        assert!(
            source.contains("Page.stopLoading not supported"),
            "StopLoading must return an explicit error, never a fake ok"
        );
    }

    // ─── canned-response eradication (source-level guarantees) ─────────
    // @trace REQ-CDP-003 [req:REQ-CDP-003] [level:unit]

    #[test]
    fn no_canned_successes_remain_in_dispatch() {
        // Every audited canned success is replaced by either a real path or an
        // explicit error. The literals below must never reappear.
        let source = include_str!("cdp_handler.rs");
        assert!(!source.contains("\"snapshot\": {}"));
        assert!(!source.contains("\"profile\": {}"));
        assert!(!source.contains("\"jsEventListeners\": 0"));
        assert!(!source.contains("\"body\": \"\""));
        assert!(!source.contains("\"identifier\": \"1\""));
    }

    #[test]
    fn profiler_and_heapprofiler_report_explicit_errors() {
        let source = include_str!("cdp_handler.rs");
        assert!(source.contains("Profiler not supported"));
        assert!(source.contains("HeapProfiler snapshot/tracking not supported"));
        assert!(source.contains("Memory.getDOMCounters not supported"));
        assert!(source.contains("Network.getResponseBody not supported"));
        assert!(source.contains("Network.setExtraHTTPHeaders not supported"));
        assert!(source.contains("Security.setOverrideCertificateErrors not supported"));
    }

    #[test]
    fn collect_garbage_uses_servo_gc_api() {
        // Real GC path: navigator.servo.GarbageCollectAllContexts() →
        // TriggerGarbageCollection → JS_GC on the script thread.
        let source = include_str!("cdp_handler.rs");
        assert!(
            source.contains("navigator.servo.GarbageCollectAllContexts()"),
            "GC must go through servo's real GC DOM API"
        );
    }

    #[test]
    fn handle_bridge_command_close_page_returns_empty() {
        let expected = json!({});
        assert_eq!(expected, json!({}));
    }

    #[test]
    fn handle_bridge_command_unsupported_returns_error() {
        // The wildcard `_` match returns Err("unsupported bridge command")
        let err_msg = "unsupported bridge command";
        assert!(!err_msg.is_empty());
    }

    // ─── json_type_string additional edge cases ────────────────────────
    // @trace REQ-CDP-005 [req:REQ-CDP-005] [level:unit]

    #[test]
    fn json_type_string_leading_dot_is_string() {
        // ".5" is not a valid f64 parse in some contexts, but Rust's parse handles it
        let result = ".5".parse::<f64>();
        if result.is_ok() {
            assert_eq!(super::json_type_string(".5"), "number");
        } else {
            assert_eq!(super::json_type_string(".5"), "string");
        }
    }

    #[test]
    fn json_type_string_positive_infinity() {
        assert_eq!(super::json_type_string("inf"), "number");
    }

    #[test]
    fn json_type_string_negative_infinity() {
        assert_eq!(super::json_type_string("-inf"), "number");
    }

    #[test]
    fn json_type_string_hex_string_is_string() {
        // "0x1A" is not a valid f64 parse, so it's "string"
        assert_eq!(super::json_type_string("0x1A"), "string");
    }

    #[test]
    fn json_type_string_very_long_number() {
        let long_num = "123456789012345678901234567890";
        // This parses as f64 (with precision loss), so it's "number"
        assert_eq!(super::json_type_string(long_num), "number");
    }

    #[test]
    fn json_type_string_mixed_alphanumeric_is_string() {
        assert_eq!(super::json_type_string("abc123"), "string");
    }

    #[test]
    fn json_type_string_empty_object_string() {
        assert_eq!(super::json_type_string("{}"), "object");
    }

    #[test]
    fn json_type_string_empty_array_string() {
        assert_eq!(super::json_type_string("[]"), "object");
    }

    // ─── json_type additional edge cases ───────────────────────────────
    // @trace REQ-CDP-005 [req:REQ-CDP-005] [level:unit]

    #[test]
    fn json_type_negative_number() {
        assert_eq!(super::json_type(&json!(-999)), "number");
    }

    #[test]
    fn json_type_large_float() {
        assert_eq!(super::json_type(&json!(f64::MIN)), "number");
    }

    #[test]
    fn json_type_deeply_nested_value() {
        let deep = json!({"a": {"b": {"c": {"d": [1, 2, {"e": true}]}}}});
        assert_eq!(super::json_type(&deep), "object");
    }

    #[test]
    fn json_type_string_with_special_chars() {
        assert_eq!(super::json_type(&json!("\n\t\r")), "string");
        assert_eq!(super::json_type(&json!("\0")), "string");
    }

    #[test]
    fn json_type_mixed_array() {
        assert_eq!(
            super::json_type(&json!([1, "two", null, true, {}])),
            "object"
        );
    }

    // ─── ServiceWorker registration JSON serialization (REQ-BRW-4 C6/C19, DF-WK-8) ───
    // @trace REQ-BRW-4 [entity:ServiceWorker] [criterion:6] [criterion:19]

    #[test]
    fn sw_registration_id_parses_double_colon_format() {
        // @trace REQ-BRW-4 [entity:ServiceWorker] DF-WK-8
        let id = super::parse_sw_registration_id("sw.js::/").unwrap();
        assert_eq!(id.script_url, "sw.js");
        assert_eq!(id.scope, "/");
    }

    #[test]
    fn sw_registration_id_parses_complex_scope() {
        let id = super::parse_sw_registration_id("https://example.com/sw.js::/app/").unwrap();
        assert_eq!(id.script_url, "https://example.com/sw.js");
        assert_eq!(id.scope, "/app/");
    }

    #[test]
    fn sw_registration_id_rejects_missing_separator() {
        assert!(super::parse_sw_registration_id("sw.js").is_err());
        assert!(super::parse_sw_registration_id("sw.js/").is_err());
    }

    #[test]
    fn sw_registration_to_json_activated() {
        // @trace REQ-BRW-4 [entity:ServiceWorker] [criterion:6] [criterion:19] DF-WK-8
        let handle = ServiceWorkerHandle::new("sw.js".to_string(), "/".to_string(), None);
        handle.transition_state(ServiceWorkerRegistrationState::Activated);
        handle.enable_fetch_interception();

        let json_val = super::sw_registration_to_json(handle);
        assert_eq!(json_val["registrationId"], "sw.js::/");
        assert_eq!(json_val["scriptURL"], "sw.js");
        assert_eq!(json_val["scope"], "/");
        assert_eq!(json_val["state"], "activated");
        assert_eq!(json_val["isActive"], true);
        // Per DEC-WK-008: fetch interception mode tracked in registry even
        // though servo upstream does not dispatch FetchEvent yet.
        assert_eq!(json_val["isFetchIntercepting"], true);
    }

    #[test]
    fn sw_registration_to_json_installing_state() {
        let handle = ServiceWorkerHandle::new("sw.js".to_string(), "/".to_string(), None);
        // Default state is Installing
        let json_val = super::sw_registration_to_json(handle);
        assert_eq!(json_val["state"], "installing");
        assert_eq!(json_val["isActive"], false);
        assert_eq!(json_val["isFetchIntercepting"], false);
    }

    #[test]
    fn sw_registration_to_json_all_states() {
        // @trace REQ-BRW-4 [entity:ServiceWorker] DF-WK-8
        let states_and_expected = vec![
            (ServiceWorkerRegistrationState::Idle, "idle"),
            (ServiceWorkerRegistrationState::Installing, "installing"),
            (ServiceWorkerRegistrationState::Installed, "installed"),
            (ServiceWorkerRegistrationState::Activating, "activating"),
            (ServiceWorkerRegistrationState::Activated, "activated"),
            (ServiceWorkerRegistrationState::Redundant, "redundant"),
        ];
        for (state, expected) in states_and_expected {
            let handle = ServiceWorkerHandle::new("sw.js".to_string(), "/".to_string(), None);
            handle.transition_state(state.clone());
            let json_val = super::sw_registration_to_json(handle);
            assert_eq!(json_val["state"], expected, "state mapping for {:?}", state);
        }
    }

    #[test]
    fn sw_registration_terminate_disables_fetch_interception() {
        // @trace REQ-BRW-4 [entity:ServiceWorker] [criterion:19] DF-WK-8
        // SPEC criterion #19: "terminate 后正确注销"
        let handle = ServiceWorkerHandle::new("sw.js".to_string(), "/".to_string(), None);
        handle.enable_fetch_interception();
        assert!(handle.is_intercepting_fetch());

        handle.terminate();

        assert!(handle.is_closing());
        // terminate() must disable fetch interception
        assert!(!handle.is_intercepting_fetch());
    }

    #[test]
    fn sw_registration_terminate_is_idempotent() {
        let handle = ServiceWorkerHandle::new("sw.js".to_string(), "/".to_string(), None);
        handle.terminate();
        handle.terminate();
        handle.terminate();
        assert!(handle.is_closing());
    }

    #[test]
    fn sw_registration_stealth_profile_inherited() {
        // @trace REQ-BRW-4 [entity:ServiceWorker] [criterion:19] DF-WK-10
        // SPEC: SW must inherit registering page's stealth profile.
        let profile = bao_stealth::StealthProfile::chrome_default();
        let handle =
            ServiceWorkerHandle::new("sw.js".to_string(), "/".to_string(), Some(profile.clone()));
        assert!(handle.stealth_profile.is_some());
        // Stealth profile is preserved across registry lookups
        let json_val = super::sw_registration_to_json(handle.clone());
        // Note: stealth profile is internal state, not serialized to CDP JSON
        // (it's used for stealth consistency verification, not CDP reporting)
        assert_eq!(json_val["scriptURL"], "sw.js");
        assert!(handle.stealth_profile.is_some());
    }

    #[test]
    fn sw_registration_id_format_with_colon_in_url() {
        // Edge case: URL containing colon (not double-colon) should parse correctly
        let id = super::parse_sw_registration_id("https://a.io/sw.js::/scope").unwrap();
        assert_eq!(id.script_url, "https://a.io/sw.js");
        assert_eq!(id.scope, "/scope");
    }
}