feat(js): expose document page boxes (#5501)

* feat(js): expose document page boxes

* Normalize page boxes for getPageBox

* Correct page box test expectations and formatting

* Use local page helper in box test

---------

Co-authored-by: FredApps <153173854+FredApps@users.noreply.github.com>

crates/engine/src/js.rs

@@ -274,12 +274,15 @@ impl JsRunner {
     /// highlights form fields (`app.runtimeHighlight`).
     pub fn new(cos: &pdfcraft_cos::Document, file_name: &str, highlight: bool) -> JsRunner {
         let xfa = pdfcraft_xfa::xfa_shape(cos).is_some();
+        let pages = pdfcraft_model::pages(cos);
         let doc = pdfcraft_js::DocInfo {
             file_name: file_name.to_string(),
-            num_pages: pdfcraft_model::pages(cos).len(),
+            num_pages: pages.len(),
             page: 0,
             info: info(cos),
             highlight,
+            page_boxes: pdfcraft_organize::page_boxes(cos).unwrap_or_default(),
+            page_rotations: pages.iter().map(|page| page.rotation(cos)).collect(),
             xfa,
         };
         // Once XFA owns the form, the PDF container's scripts belong to its fallback view.

crates/engine/src/tests.rs

@@ -6753,6 +6753,25 @@ fn inactive_xfa_and_ordinary_pdfs_keep_document_helpers_and_alerts() {
     }
 }
 
+#[test]
+fn js_get_page_box_reads_effective_boxes_without_editing_the_document() {
+    let (mut s, id) = session_with(1);
+    let before = s.get(id).expect("opened document").can_undo().map(str::to_owned);
+    let out = s
+        .run_javascript(id, "JSON.stringify([this.getPageBox(), this.getPageBox('Media', 0), this.getPageBox('Trim', 0)])", None)
+        .expect("script runs");
+    assert_eq!(out.error, None, "{out:?}");
+    assert_eq!(out.result.as_deref(), Some("[[0,300,200,0],[0,300,200,0],[0,300,200,0]]"));
+    assert_eq!(s.get(id).expect("document remains open").can_undo(), before.as_deref());
+
+    s.apply(id, Edit::RotatePages { pages: vec![0], degrees: 90 }).expect("rotate page");
+    let before = s.get(id).expect("rotated document").can_undo().map(str::to_owned);
+    let out = s.run_javascript(id, "JSON.stringify(this.getPageBox('Crop', 0))", None).expect("script runs");
+    assert_eq!(out.error, None, "{out:?}");
+    assert_eq!(out.result.as_deref(), Some("[0,200,300,0]"));
+    assert_eq!(s.get(id).expect("document remains open").can_undo(), before.as_deref());
+}
+
 #[test]
 fn automatic_field_scripts_cannot_print() {
     use pdfcraft_forms::{FieldEvent, Scripts};