car-browser 0.12.0

Browser automation and perception pipeline for Common Agent Runtime
Documentation
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
//! Headless Chromium backend via chromiumoxide.
//!
//! Implements `BrowserBackend` using Chrome DevTools Protocol (CDP).
//! Requires a Chromium/Chrome binary on the system.

#![cfg(feature = "chromium")]

use async_trait::async_trait;
use chromiumoxide::browser::{Browser, BrowserConfig};
use chromiumoxide::cdp::browser_protocol::accessibility::GetFullAxTreeParams;
use chromiumoxide::cdp::browser_protocol::dom::{BackendNodeId, FocusParams, GetBoxModelParams};
use chromiumoxide::cdp::browser_protocol::input::{
    DispatchKeyEventParams, DispatchKeyEventType, DispatchMouseEventParams, DispatchMouseEventType,
    MouseButton,
};
use chromiumoxide::cdp::browser_protocol::page::CaptureScreenshotFormat;
use chromiumoxide::Page;
use futures::StreamExt;
use std::collections::HashMap;
use std::sync::Arc;
use tokio::sync::RwLock;

use crate::backend::{BrowserBackend, BrowserError};
use crate::models::{A11yNode, Bounds, Modifier, Viewport, WaitCondition};

/// Cached mapping from ax_N node IDs to their CDP backend DOM node IDs.
/// Populated during `get_accessibility_tree()`, consumed by `click_element()`
/// and `focus_element()`.
type AxNodeCache = HashMap<String, BackendNodeId>;

/// Headless Chromium browser backend.
pub struct ChromiumBackend {
    page: Arc<RwLock<Option<Page>>>,
    _browser: Arc<RwLock<Option<Browser>>>,
    viewport_width: u32,
    viewport_height: u32,
    /// Cached URL, updated on navigate() and get_accessibility_tree().
    /// Uses std::sync::RwLock so get_current_url() can be synchronous.
    cached_url: std::sync::RwLock<String>,
    /// Cached mapping from ax_N IDs to BackendNodeId, populated by
    /// get_accessibility_tree(). Used by click_element/focus_element/type_into_element
    /// to resolve ax_N to real DOM coordinates.
    ax_node_cache: std::sync::RwLock<AxNodeCache>,
    /// Per-instance Chromium profile directory. Held so the
    /// directory survives until ChromiumBackend is dropped, then
    /// auto-cleans (TempDir runs `remove_dir_all` in its Drop).
    /// `None` when the caller passed an explicit profile dir via
    /// `CAR_BROWSER_PROFILE_DIR` — caller owns lifecycle in that case.
    /// See #148: under Playwright workers running in parallel, the
    /// chromiumoxide default profile dir caused SingletonLock
    /// contention; per-instance dirs eliminate the collision.
    _profile_dir: Option<tempfile::TempDir>,
}

/// True iff `url` is on the same (scheme, host, port) as `origin`.
///
/// Used to enforce origin-locality for `set_local_storage`: localStorage is
/// origin-scoped in the browser, so setting items from the wrong page would
/// either fail silently or mutate the wrong origin's state. We require the
/// caller to navigate to the origin first.
fn current_origin_matches(url: &str, origin: &str) -> bool {
    // Empty or `about:blank` is allowed — treat as a pre-page state where
    // localStorage operations will be attached to the first real
    // navigation. Chromium's about:blank has no persistent storage so the
    // `evaluate` call will simply set localStorage on the next real page.
    if url.is_empty() || url.starts_with("about:") {
        return true;
    }
    let extract = |s: &str| {
        let (scheme, rest) = s.split_once("://")?;
        let host_part = rest.split('/').next().unwrap_or("");
        Some(format!("{}://{}", scheme, host_part))
    };
    match (extract(url), extract(origin)) {
        (Some(a), Some(b)) => a == b,
        _ => false,
    }
}

/// Convert our `Modifier` enum to CDP modifier bitmask.
/// CDP defines: Alt=1, Ctrl=2, Meta/Command=4, Shift=8.
fn modifiers_to_cdp_flags(modifiers: &[Modifier]) -> i64 {
    let mut flags: i64 = 0;
    for m in modifiers {
        flags |= match m {
            Modifier::Alt => 1,
            Modifier::Control => 2,
            Modifier::Meta => 4,
            Modifier::Shift => 8,
        };
    }
    flags
}

/// Options for launching a `ChromiumBackend`.
///
/// `headless = false` shows a real visible Chromium window — intended for
/// interactive flows like first-time authentication (LinkedIn, OAuth, SSO)
/// where a human needs to complete sign-in / 2FA / captcha before the rest
/// of the script runs headless against the persisted cookies.
#[derive(Debug, Clone)]
pub struct LaunchOptions {
    pub width: u32,
    pub height: u32,
    pub headless: bool,
    /// Extra command-line flags appended to Chromium's argv at
    /// launch. Use cases include the Google Meet bot (#112) which
    /// needs `--use-fake-ui-for-media-stream`,
    /// `--autoplay-policy=no-user-gesture-required`, and the
    /// container-friendly trio (`--no-sandbox`,
    /// `--disable-dev-shm-usage`, `--disable-setuid-sandbox`).
    /// Flags are passed verbatim — callers responsible for the
    /// correctness of what they append.
    pub extra_args: Vec<String>,
}

impl Default for LaunchOptions {
    fn default() -> Self {
        Self {
            width: 1280,
            height: 720,
            headless: true,
            extra_args: Vec::new(),
        }
    }
}

impl ChromiumBackend {
    /// Launch a new headless Chromium instance.
    pub async fn launch() -> Result<Self, BrowserError> {
        Self::launch_with_viewport(1280, 720).await
    }

    /// Launch with specific viewport dimensions (headless).
    pub async fn launch_with_viewport(width: u32, height: u32) -> Result<Self, BrowserError> {
        Self::launch_with_options(LaunchOptions {
            width,
            height,
            headless: true,
            extra_args: Vec::new(),
        })
        .await
    }

    /// Launch with full options, including headless/headed toggle.
    ///
    /// `headless = true` uses Chromium's new headless mode (`--headless=new`);
    /// `headless = false` shows a visible window (for interactive auth etc.).
    pub async fn launch_with_options(opts: LaunchOptions) -> Result<Self, BrowserError> {
        let mut builder = BrowserConfig::builder().window_size(opts.width, opts.height);
        builder = if opts.headless {
            builder.new_headless_mode()
        } else {
            builder.with_head()
        };
        if !opts.extra_args.is_empty() {
            // chromiumoxide's BrowserConfig::builder().args takes
            // an `IntoIterator<Item = impl Into<String>>` and
            // appends each verbatim to Chromium's argv.
            builder = builder.args(opts.extra_args.iter().map(String::as_str));
        }

        // Per-instance Chromium profile directory.
        //
        // chromiumoxide defaults to a fixed path under $TMPDIR;
        // when the same default is reused by N parallel processes
        // (e.g. Playwright workers each constructing a CarRuntime),
        // they contend over Chromium's `SingletonLock` and the
        // losers either silently get a wrong-port DevTools handshake
        // or hang on navigate (#148).
        //
        // Each ChromiumBackend now gets its own tempdir, scoped to
        // its lifetime. Callers who *want* persistence (cookies +
        // localStorage between runs) can set CAR_BROWSER_PROFILE_DIR
        // and accept they're back on the hook for parallel-launch
        // coordination.
        let (profile_dir, profile_handle) = match std::env::var("CAR_BROWSER_PROFILE_DIR") {
            Ok(path) if !path.is_empty() => (std::path::PathBuf::from(path), None),
            _ => {
                let td = tempfile::Builder::new()
                    .prefix("car-browser-profile-")
                    .tempdir()
                    .map_err(|e| {
                        BrowserError::NotAvailable(format!("create per-instance profile dir: {e}"))
                    })?;
                (td.path().to_path_buf(), Some(td))
            }
        };
        builder = builder.user_data_dir(&profile_dir);

        let config = builder
            .build()
            .map_err(|e| BrowserError::NotAvailable(format!("Config error: {}", e)))?;

        let (browser, mut handler) = Browser::launch(config)
            .await
            .map_err(|e| BrowserError::NotAvailable(format!("Failed to launch Chrome: {}", e)))?;

        // Spawn the CDP event handler
        tokio::spawn(async move { while let Some(_event) = handler.next().await {} });

        let page = browser
            .new_page("about:blank")
            .await
            .map_err(|e| BrowserError::NotAvailable(format!("Failed to create page: {}", e)))?;

        Ok(Self {
            page: Arc::new(RwLock::new(Some(page))),
            _browser: Arc::new(RwLock::new(Some(browser))),
            viewport_width: opts.width,
            viewport_height: opts.height,
            cached_url: std::sync::RwLock::new("about:blank".to_string()),
            ax_node_cache: std::sync::RwLock::new(HashMap::new()),
            _profile_dir: profile_handle,
        })
    }

    async fn get_page(&self) -> Result<Page, BrowserError> {
        self.page
            .read()
            .await
            .clone()
            .ok_or(BrowserError::NotAvailable("Page closed".into()))
    }

    /// Update the cached URL by querying the page asynchronously.
    async fn refresh_cached_url(&self) {
        if let Ok(page) = self.get_page().await {
            if let Ok(Some(url)) = page.url().await {
                if let Ok(mut cached) = self.cached_url.write() {
                    *cached = url;
                }
            }
        }
    }

    /// Look up the BackendNodeId for an ax_N node ID from the cache.
    fn resolve_backend_node_id(&self, node_id: &str) -> Result<BackendNodeId, BrowserError> {
        let cache = self.ax_node_cache.read().map_err(|e| {
            BrowserError::PlatformInternal(format!("Failed to read ax_node_cache: {}", e))
        })?;
        cache.get(node_id).copied().ok_or_else(|| {
            BrowserError::ElementNotFound(format!(
                "No cached BackendNodeId for '{}'. Call get_accessibility_tree() first.",
                node_id
            ))
        })
    }

    /// Get the bounding box center for a BackendNodeId via CDP DOM.getBoxModel.
    async fn get_element_center(
        &self,
        backend_node_id: BackendNodeId,
    ) -> Result<(f64, f64), BrowserError> {
        let page = self.get_page().await?;
        let params = GetBoxModelParams::builder()
            .backend_node_id(backend_node_id)
            .build();
        let result = page
            .execute(params)
            .await
            .map_err(|e| BrowserError::ElementNotFound(format!("DOM.getBoxModel failed: {}", e)))?;

        // The content quad is 8 floats: [x1,y1, x2,y2, x3,y3, x4,y4]
        let quad = result.result.model.content.inner();
        if quad.len() < 8 {
            return Err(BrowserError::PlatformInternal(
                "Content quad has fewer than 8 values".into(),
            ));
        }
        // Compute center from the four corners
        let cx = (quad[0] + quad[2] + quad[4] + quad[6]) / 4.0;
        let cy = (quad[1] + quad[3] + quad[5] + quad[7]) / 4.0;
        Ok((cx, cy))
    }

    /// Focus a DOM element by BackendNodeId via CDP DOM.focus.
    async fn focus_by_backend_node_id(
        &self,
        backend_node_id: BackendNodeId,
    ) -> Result<(), BrowserError> {
        let page = self.get_page().await?;
        let params = FocusParams::builder()
            .backend_node_id(backend_node_id)
            .build();
        page.execute(params)
            .await
            .map_err(|e| BrowserError::InputFailed(format!("DOM.focus failed: {}", e)))?;
        Ok(())
    }
}

#[async_trait]
impl BrowserBackend for ChromiumBackend {
    async fn capture_screenshot(&self) -> Result<Vec<u8>, BrowserError> {
        let page = self.get_page().await?;
        page.screenshot(
            chromiumoxide::page::ScreenshotParams::builder()
                .format(CaptureScreenshotFormat::Png)
                .build(),
        )
        .await
        .map_err(|e| BrowserError::ScreenshotFailed(e.to_string()))
    }

    async fn get_accessibility_tree(&self) -> Result<Vec<A11yNode>, BrowserError> {
        let page = self.get_page().await?;
        let result = page
            .execute(GetFullAxTreeParams::default())
            .await
            .map_err(|e| BrowserError::AccessibilityFailed(e.to_string()))?;

        // Update cached URL while we have the page
        self.refresh_cached_url().await;

        let mut new_cache = AxNodeCache::new();

        let mut nodes: Vec<A11yNode> = Vec::new();
        for (i, n) in result.result.nodes.iter().enumerate() {
            if n.ignored {
                continue;
            }

            let ax_id = format!("ax_{}", i);

            // Cache the BackendNodeId for later use by click_element/focus_element
            if let Some(backend_id) = n.backend_dom_node_id {
                new_cache.insert(ax_id.clone(), backend_id);
            }

            let role = n
                .role
                .as_ref()
                .and_then(|r| r.value.as_ref())
                .and_then(|v| v.as_str())
                .unwrap_or("unknown")
                .to_string();

            let name = n
                .name
                .as_ref()
                .and_then(|v| v.value.as_ref())
                .and_then(|v| v.as_str())
                .filter(|s| !s.is_empty())
                .map(|s| s.to_string());

            let value = n
                .value
                .as_ref()
                .and_then(|v| v.value.as_ref())
                .and_then(|v| v.as_str())
                .filter(|s| !s.is_empty())
                .map(|s| s.to_string());

            let children: Vec<String> = n
                .child_ids
                .as_ref()
                .map(|ids| ids.iter().map(|id| format!("ax_{}", id.as_ref())).collect())
                .unwrap_or_default();

            // Resolve real bounds via DOM.getBoxModel if we have a backend node ID.
            // Fall back to zero-sized bounds for nodes without a DOM backing (e.g. root).
            let bounds = if let Some(backend_id) = n.backend_dom_node_id {
                let bm_params = GetBoxModelParams::builder()
                    .backend_node_id(backend_id)
                    .build();
                if let Ok(bm_result) = page.execute(bm_params).await {
                    let quad = bm_result.result.model.content.inner();
                    if quad.len() >= 8 {
                        let x = quad[0];
                        let y = quad[1];
                        let width = quad[2] - quad[0];
                        let height = quad[5] - quad[1];
                        Bounds::new(x, y, width.max(0.0), height.max(0.0))
                    } else {
                        Bounds::new(0.0, 0.0, 0.0, 0.0)
                    }
                } else {
                    Bounds::new(0.0, 0.0, 0.0, 0.0)
                }
            } else {
                Bounds::new(0.0, 0.0, 0.0, 0.0)
            };

            nodes.push(A11yNode {
                node_id: ax_id,
                role,
                name,
                value,
                bounds,
                children,
                focusable: true,
                focused: false,
                disabled: false,
            });
        }

        // Update the shared cache
        if let Ok(mut cache) = self.ax_node_cache.write() {
            *cache = new_cache;
        }

        Ok(nodes)
    }

    fn get_viewport(&self) -> Result<Viewport, BrowserError> {
        Ok(Viewport {
            width: self.viewport_width,
            height: self.viewport_height,
            device_pixel_ratio: 1.0,
        })
    }

    fn get_current_url(&self) -> Result<String, BrowserError> {
        self.cached_url
            .read()
            .map(|url| url.clone())
            .map_err(|e| BrowserError::PlatformInternal(format!("URL cache lock poisoned: {}", e)))
    }

    async fn get_page_title(&self) -> Result<String, BrowserError> {
        let page = self.get_page().await?;
        page.evaluate("document.title")
            .await
            .map_err(|e| BrowserError::PlatformInternal(e.to_string()))?
            .into_value::<String>()
            .map_err(|e| BrowserError::PlatformInternal(e.to_string()))
    }

    async fn navigate(&self, url: &str) -> Result<(), BrowserError> {
        let page = self.get_page().await?;
        page.goto(url)
            .await
            .map_err(|e| BrowserError::NavigationFailed(e.to_string()))?;
        page.wait_for_navigation()
            .await
            .map_err(|e| BrowserError::NavigationFailed(e.to_string()))?;

        // Update cached URL after navigation
        if let Ok(mut cached) = self.cached_url.write() {
            *cached = url.to_string();
        }
        // Also refresh from the page in case of redirects
        self.refresh_cached_url().await;

        Ok(())
    }

    async fn inject_click(&self, x: f64, y: f64) -> Result<(), BrowserError> {
        let page = self.get_page().await?;
        page.execute(
            DispatchMouseEventParams::builder()
                .r#type(DispatchMouseEventType::MousePressed)
                .x(x)
                .y(y)
                .button(MouseButton::Left)
                .click_count(1)
                .build()
                .unwrap(),
        )
        .await
        .map_err(|e| BrowserError::InputFailed(e.to_string()))?;

        page.execute(
            DispatchMouseEventParams::builder()
                .r#type(DispatchMouseEventType::MouseReleased)
                .x(x)
                .y(y)
                .button(MouseButton::Left)
                .click_count(1)
                .build()
                .unwrap(),
        )
        .await
        .map_err(|e| BrowserError::InputFailed(e.to_string()))?;

        Ok(())
    }

    async fn inject_text(&self, text: &str) -> Result<(), BrowserError> {
        let page = self.get_page().await?;
        for ch in text.chars() {
            page.execute(
                DispatchKeyEventParams::builder()
                    .r#type(DispatchKeyEventType::Char)
                    .text(ch.to_string())
                    .build()
                    .unwrap(),
            )
            .await
            .map_err(|e| BrowserError::InputFailed(e.to_string()))?;
        }
        Ok(())
    }

    async fn inject_keypress(&self, key: &str, modifiers: &[Modifier]) -> Result<(), BrowserError> {
        let page = self.get_page().await?;
        let cdp_modifiers = modifiers_to_cdp_flags(modifiers);

        page.execute(
            DispatchKeyEventParams::builder()
                .r#type(DispatchKeyEventType::KeyDown)
                .key(key.to_string())
                .modifiers(cdp_modifiers)
                .build()
                .unwrap(),
        )
        .await
        .map_err(|e| BrowserError::InputFailed(e.to_string()))?;

        page.execute(
            DispatchKeyEventParams::builder()
                .r#type(DispatchKeyEventType::KeyUp)
                .key(key.to_string())
                .modifiers(cdp_modifiers)
                .build()
                .unwrap(),
        )
        .await
        .map_err(|e| BrowserError::InputFailed(e.to_string()))?;

        Ok(())
    }

    async fn inject_scroll(&self, delta_y: i32) -> Result<(), BrowserError> {
        let page = self.get_page().await?;
        page.execute(
            DispatchMouseEventParams::builder()
                .r#type(DispatchMouseEventType::MouseWheel)
                .x(self.viewport_width as f64 / 2.0)
                .y(self.viewport_height as f64 / 2.0)
                .delta_x(0.0)
                .delta_y(delta_y as f64)
                .build()
                .unwrap(),
        )
        .await
        .map_err(|e| BrowserError::InputFailed(e.to_string()))?;
        Ok(())
    }

    async fn click_element(&self, node_id: &str) -> Result<(), BrowserError> {
        let backend_node_id = self.resolve_backend_node_id(node_id)?;
        let (cx, cy) = self.get_element_center(backend_node_id).await?;
        self.inject_click(cx, cy).await
    }

    async fn type_into_element(&self, node_id: &str, text: &str) -> Result<(), BrowserError> {
        let backend_node_id = self.resolve_backend_node_id(node_id)?;
        self.focus_by_backend_node_id(backend_node_id).await?;
        self.inject_text(text).await
    }

    async fn focus_element(&self, node_id: &str) -> Result<(), BrowserError> {
        let backend_node_id = self.resolve_backend_node_id(node_id)?;
        self.focus_by_backend_node_id(backend_node_id).await
    }

    async fn is_page_loaded(&self) -> Result<bool, BrowserError> {
        let page = self.get_page().await?;
        let state = page
            .evaluate("document.readyState")
            .await
            .map_err(|e| BrowserError::PlatformInternal(e.to_string()))?
            .into_value::<String>()
            .unwrap_or_default();
        Ok(state == "complete")
    }

    async fn wait_until(
        &self,
        condition: &WaitCondition,
        timeout_ms: u64,
    ) -> Result<bool, BrowserError> {
        let deadline = tokio::time::Instant::now() + tokio::time::Duration::from_millis(timeout_ms);

        // Snapshot the URL at entry for UrlChanged comparisons.
        // Errors here turn into an empty baseline rather than
        // failing the wait — a missing baseline matches anything.
        let entry_url = self.get_current_url().unwrap_or_default();

        loop {
            let met = match condition {
                WaitCondition::PageLoaded => self.is_page_loaded().await?,
                WaitCondition::UrlChanged => {
                    let now = self.get_current_url().unwrap_or_default();
                    !now.is_empty() && now != entry_url
                }
                WaitCondition::A11yContainsText { text } => {
                    let needle = text.to_lowercase();
                    let nodes = self.get_accessibility_tree().await?;
                    nodes.iter().any(|n| {
                        n.name
                            .as_ref()
                            .map(|name| name.to_lowercase().contains(&needle))
                            .unwrap_or(false)
                    })
                }
                WaitCondition::ElementWithName {
                    name_contains,
                    role,
                } => {
                    self.element_exists_a11y(name_contains, role.as_deref())
                        .await?
                }
            };
            if met {
                return Ok(true);
            }
            if tokio::time::Instant::now() >= deadline {
                return Ok(false);
            }
            tokio::time::sleep(tokio::time::Duration::from_millis(100)).await;
        }
    }

    async fn element_exists_a11y(
        &self,
        name_contains: &str,
        role: Option<&str>,
    ) -> Result<bool, BrowserError> {
        let nodes = self.get_accessibility_tree().await?;
        Ok(nodes.iter().any(|n| {
            let name_match = n
                .name
                .as_ref()
                .map(|name| name.to_lowercase().contains(&name_contains.to_lowercase()))
                .unwrap_or(false);
            if !name_match {
                return false;
            }
            match role {
                Some(r) => n.role.to_lowercase() == r.to_lowercase(),
                None => true,
            }
        }))
    }

    async fn set_cookies(
        &self,
        cookies: &[crate::models::CookieParam],
    ) -> Result<(), BrowserError> {
        let page = self.get_page().await?;
        for cookie in cookies {
            let mut cdp_cookie = chromiumoxide::cdp::browser_protocol::network::CookieParam::new(
                &cookie.name,
                &cookie.value,
            );
            cdp_cookie.domain = Some(cookie.domain.clone());
            cdp_cookie.path = Some(cookie.path.clone());
            if cookie.secure {
                cdp_cookie.secure = Some(true);
            }
            if cookie.http_only {
                cdp_cookie.http_only = Some(true);
            }
            page.set_cookie(cdp_cookie)
                .await
                .map_err(|e| BrowserError::PlatformInternal(format!("set_cookie failed: {}", e)))?;
        }
        Ok(())
    }

    async fn set_local_storage(
        &self,
        origin: &str,
        items: &[(String, String)],
    ) -> Result<(), BrowserError> {
        let page = self.get_page().await?;
        // localStorage is origin-scoped — require the page already be at
        // the target origin so we don't silently navigate behind the
        // caller's back. Callers replay via `set_local_storage` after a
        // `navigate` to the matching origin (or before first `navigate`
        // if the caller wants the script to navigate elsewhere).
        let current = self.get_current_url().unwrap_or_default();
        if !current_origin_matches(&current, origin) {
            return Err(BrowserError::PlatformInternal(format!(
                "set_local_storage: page must be at origin '{}' first (currently '{}'). \
                 Add a `navigate` op before set_local_storage, or call set_local_storage \
                 before any navigate (pre-page state).",
                origin, current
            )));
        }

        // Don't swallow JSON encoding errors — `serde_json::to_string` on a
        // &str can fail in theory; treat that as a platform bug, not a
        // silent empty string.
        for (key, value) in items {
            let k = serde_json::to_string(key)
                .map_err(|e| BrowserError::PlatformInternal(format!("encode key: {}", e)))?;
            let v = serde_json::to_string(value)
                .map_err(|e| BrowserError::PlatformInternal(format!("encode value: {}", e)))?;
            let js = format!("localStorage.setItem({}, {})", k, v);
            page.evaluate(js).await.map_err(|e| {
                BrowserError::PlatformInternal(format!("localStorage.setItem failed: {}", e))
            })?;
        }
        Ok(())
    }

    async fn set_extra_headers(&self, headers: &[(String, String)]) -> Result<(), BrowserError> {
        let page = self.get_page().await?;
        // Enable network domain first
        page.execute(chromiumoxide::cdp::browser_protocol::network::EnableParams::default())
            .await
            .map_err(|e| BrowserError::PlatformInternal(format!("network enable failed: {}", e)))?;

        let header_obj: serde_json::Value = headers
            .iter()
            .map(|(k, v)| (k.clone(), serde_json::Value::String(v.clone())))
            .collect::<serde_json::Map<String, serde_json::Value>>()
            .into();
        let params = chromiumoxide::cdp::browser_protocol::network::SetExtraHttpHeadersParams::new(
            chromiumoxide::cdp::browser_protocol::network::Headers::new(header_obj),
        );
        page.execute(params).await.map_err(|e| {
            BrowserError::PlatformInternal(format!("set_extra_headers failed: {}", e))
        })?;
        Ok(())
    }

    async fn shutdown(&self) -> Result<(), BrowserError> {
        if let Some(page) = self.page.write().await.take() {
            let _ = page.close().await;
        }
        self._browser.write().await.take();
        Ok(())
    }
}