diff --git a/crates/edit/src/added.rs b/crates/edit/src/added.rs index 671a72a1b..d39bb0fa9 100644 --- a/crates/edit/src/added.rs +++ b/crates/edit/src/added.rs @@ -1050,6 +1050,9 @@ fn write(doc: &mut Document, page: usize, c: &Content, obj: Option) -> R } let taken = pres.get(b"Font").map(|f| doc.resolve(f)).and_then(|f| f.as_dict().cloned()).unwrap_or_default(); let (content, res) = draw(doc, c, view, &taken, obj.is_some())?; + if obj.is_none() { + crate::check_on_top(doc, p)?; + } for (k, v) in res.iter() { let mut sub = pres.get(k).map(|s| doc.resolve(s)).and_then(|s| s.as_dict().cloned()).unwrap_or_default(); for (n2, o) in v.as_dict().into_iter().flat_map(|d| d.iter()) { diff --git a/crates/edit/src/flatten.rs b/crates/edit/src/flatten.rs index ac90dda11..1fe1324b4 100644 --- a/crates/edit/src/flatten.rs +++ b/crates/edit/src/flatten.rs @@ -257,6 +257,7 @@ fn flatten_which(doc: &mut Document, pages: &[usize], which: Which) -> Result (behind_marks < list.len()).then_some((behind_marks, unclosed, marked)), // Content left inside an optional-content sequence it cannot close could be hidden. - Isolation::TooDeep => { - return Err(EditError::Invalid("the page's marked content is nested too deeply to add anything on top of it".into())); - } + Isolation::TooDeep => return Err(too_deep_on_top()), } }; let mark_ref = doc.add(Object::Stream(Stream::flate(tagged(tag), &content))); @@ -661,6 +659,26 @@ fn place_tagged(doc: &mut Document, page: &pdfcraft_model::Page, tag: &str, cont Ok(mark_ref) } +fn too_deep_on_top() -> EditError { + EditError::Invalid("the page's marked content is nested too deeply to add anything on top of it".into()) +} + +/// The refusal [`place_tagged`] gives for a mark on top of `page`, checked before an edit changes +/// anything (removing old marks, adding resources) so a refused edit leaves the document as it was. +fn check_on_top(doc: &Document, page: &pdfcraft_model::Page) -> Result<(), EditError> { + let obj = doc.get(page.obj); + let list = match obj.as_dict().and_then(|d| d.get(b"Contents")) { + None => return Ok(()), + Some(Object::Ref(r)) => doc.get(*r).as_array().cloned().unwrap_or_else(|| vec![Object::Ref(*r)]), + Some(Object::Array(a)) => a.clone(), + Some(other) => vec![other.clone()], + }; + match isolation(doc, &list) { + Isolation::TooDeep => Err(too_deep_on_top()), + _ => Ok(()), + } +} + /// Put content tagged `tag` first inside the q/Q wrapper, so it applies to the page's original /// content and nothing else (a header's shrink). A page without a wrapper has no original content /// on it and is left alone. @@ -680,6 +698,7 @@ fn place_inside_wrapper(doc: &mut Document, page: &pdfcraft_model::Page, tag: &s pub fn stamp(doc: &mut Document, page: usize, tag: &str, content: Vec) -> Result { let all = page_list(doc); check(&[page], all.len())?; + check_on_top(doc, &all[page])?; add_resources(doc, &all[page], None, Some(&content))?; let p = page_list(doc).swap_remove(page); place_tagged(doc, &p, tag, content, false) @@ -759,6 +778,9 @@ pub fn add_header_footer(doc: &mut Document, pages: &[usize], hf: &HeaderFooter, .iter() .map(|&i| hf.shrink.then(|| shrink_matrix(hf, all[i].display_size(doc), all[i].view_matrix(doc))).transpose()) .collect::, _>>()?; + for &i in pages { + check_on_top(doc, &all[i])?; + } if replace { remove_marks(doc, pages, MarkKind::HeaderFooter)?; } @@ -847,6 +869,11 @@ pub fn add_watermark(doc: &mut Document, pages: &[usize], wm: &Watermark, replac { return Err(EditError::Invalid("invalid watermark settings".into())); } + if !wm.behind { + for &i in pages { + check_on_top(doc, &all[i])?; + } + } if replace { remove_marks(doc, pages, MarkKind::Watermark)?; } diff --git a/crates/edit/src/marked_isolation_tests.rs b/crates/edit/src/marked_isolation_tests.rs index 571bd9c24..227371bca 100644 --- a/crates/edit/src/marked_isolation_tests.rs +++ b/crates/edit/src/marked_isolation_tests.rs @@ -131,3 +131,29 @@ fn depth_budget_bounds_emitted_closures_and_overflow_is_refused_on_top() { place_tagged(&mut doc, &page, MarkKind::Background.tag(), b"q Q\n".to_vec(), true).unwrap(); } } + +/// Marks refused on top of content nested past the depth budget leave the page as it was: old +/// marks are not removed and no resources are added before the refusal. +#[test] +fn a_mark_refused_on_top_changes_nothing() { + let mut over = b"/Artifact BMC\n".repeat(ISOLATION_MAX_DEPTH); + over.extend_from_slice(b"/Artifact BMC\n"); + let mut doc = fixture(&[&over]); + let behind = Watermark { text: "OLD".into(), behind: true, ..Watermark::default() }; + add_watermark(&mut doc, &[0], &behind, false).unwrap(); + let page = page_list(&doc).remove(0).obj; + let before = (*doc.get(page)).clone(); + let on_top = Watermark { text: "NEW".into(), ..Watermark::default() }; + assert!(matches!(add_watermark(&mut doc, &[0], &on_top, true), Err(EditError::Invalid(_)))); + assert_eq!((*doc.get(page)).clone(), before, "the old watermark stays"); + let hf = HeaderFooter { + text: [String::new(), "Top".into(), String::new(), String::new(), String::new(), String::new()], + font: added::Family::Times, + ..HeaderFooter::default() + }; + assert!(matches!(add_header_footer(&mut doc, &[0], &hf, true, &Context::default()), Err(EditError::Invalid(_)))); + assert_eq!((*doc.get(page)).clone(), before, "no fonts are added"); + let mut stamped = doc.clone(); + assert!(matches!(stamp(&mut stamped, 0, "Probe", b"/PCTimes 9 Tf\n".to_vec()), Err(EditError::Invalid(_)))); + assert_eq!((*stamped.get(page)).clone(), before, "no fonts are added"); +}