🐝 Restore wrapped footnote highlighting

package.json

@@ -6,7 +6,7 @@
   "scripts": {
     "build": "node scripts/build.mjs",
     "check": "node scripts/check-extension.mjs",
-    "test": "node --test tests/enhancer-setup.test.mjs tests/document-title.test.mjs tests/metadata-doi.test.mjs tests/local-file-favicon.test.mjs tests/page-tab-labels.test.mjs tests/minimap.test.mjs tests/clickable-reference-links.test.mjs tests/printed-page-jump.test.mjs tests/markdown-copy.test.mjs tests/terminal-punctuation-selection.test.mjs tests/footnote-click-copy.test.mjs tests/chatgpt-summary-popup.test.mjs tests/chatgpt-pdf-relay.test.mjs tests/selection-gaps.test.mjs"
+    "test": "node --test tests/enhancer-setup.test.mjs tests/document-title.test.mjs tests/metadata-doi.test.mjs tests/local-file-favicon.test.mjs tests/page-tab-labels.test.mjs tests/minimap.test.mjs tests/clickable-reference-links.test.mjs tests/printed-page-jump.test.mjs tests/markdown-copy.test.mjs tests/terminal-punctuation-selection.test.mjs tests/footnote-click-copy.test.mjs tests/footnote-fallback-wrap.test.mjs tests/chatgpt-summary-popup.test.mjs tests/chatgpt-pdf-relay.test.mjs tests/selection-gaps.test.mjs"
   },
   "dependencies": {
     "pdfjs-dist": "6.3.289",

src/viewer/navigation/footnote-index.js

@@ -90,13 +90,18 @@ export function candidateForPage(items, viewport, number, pageNumber, originPage
       continue;
     }
 
+    const paragraph = fallbackFootnoteParagraph(items, viewport, item,
+      adjacentText ? next : item, number, pageNumber);
     const candidate = {
       pageNumber,
       score,
       xRatio: coordinates.xRatio,
       yRatio: coordinates.yRatio,
       label: text,
-      highlightRegions: [{ pageNumber, ...textRegion({ ...coordinates, height: itemHeight, item }, viewport) }],
+      text: paragraph?.text || remainder,
+      highlightRegions: paragraph?.highlightRegions?.length
+        ? paragraph.highlightRegions
+        : [{ pageNumber, ...textRegion({ ...coordinates, height: itemHeight, item }, viewport) }],
     };
 
     if (!best || candidate.score > best.score) {
@@ -154,6 +159,49 @@ function highlightRegions(entries, viewport, pageNumber) {
   return lines.map(({ baseline, ...region }) => ({ pageNumber, ...region }));
 }
 
+// Fallback candidates can contain only the first PDF.js text item of a note.
+// Follow nearby, same-size lines conservatively so wrapped notes are highlighted
+// and copied in full, without crossing a new note or the printed page footer.
+function fallbackFootnoteParagraph(items, viewport, markerItem, bodyItem, number, pageNumber) {
+  const entries = positionedItems(items, viewport).sort(readingOrder);
+  const marker = entries.find((entry) => entry.item === markerItem);
+  const body = entries.find((entry) => entry.item === bodyItem);
+  if (!marker || !body) return null;
+  const height = body.height || marker.height;
+  if (!height) return null;
+  const firstBaseline = readingBaseline(body);
+  const minX = Math.max(0, Math.min(marker.x, body.x) - height * 4);
+  const maxX = Math.min(viewport.width * 0.96,
+    Math.max(viewport.width * 0.5, body.x + Math.abs(body.item.width || 0) + height * 3));
+  const selected = [];
+  let lastBaseline = firstBaseline;
+
+  for (const entry of entries) {
+    const baseline = readingBaseline(entry);
+    if (baseline < firstBaseline - Math.max(2, height * 0.4)) continue;
+    if (entry.yRatio >= 0.94) break;
+    if (entry.x < minX || entry.x > maxX) continue;
+    const laterLine = baseline > lastBaseline + Math.max(2, height * 0.25);
+    if (laterLine && (baseline - lastBaseline > height * 1.9 ||
+      (entry.x <= marker.x + height &&
+        /^\d{1,3}(?:[.)]|\s|$)/.test(entry.text)))) break;
+    if (entry !== marker && Math.abs(entry.height - height) > height * 0.35) {
+      if (laterLine) break;
+      continue;
+    }
+    if (baseline > firstBaseline + 2 && /^\d+$/.test(entry.text) &&
+      entry.yRatio >= 0.9) break;
+    if (baseline <= firstBaseline + 2 && entry.x < marker.x - 2) continue;
+    selected.push(entry);
+    lastBaseline = Math.max(lastBaseline, baseline);
+  }
+
+  if (!selected.includes(marker)) selected.unshift(marker);
+  const rawText = joinNoteEntries(selected.filter((entry) => entry !== marker || marker === body));
+  const text = (marker === body ? rawText.replace(markerPattern(number), "") : rawText).trim();
+  return { text, highlightRegions: highlightRegions(selected, viewport, pageNumber) };
+}
+
 function readingBaseline(entry) {
   // OCR words on a tilted scan share a sloped baseline. Compare their
   // deskewed positions while retaining original coordinates for highlights.
@@ -455,10 +503,29 @@ export function footnotesForPage(items, viewport, pageNumber, rules = [], refere
         (note.hangingMargin === undefined ? entry.yRatio === note.yRatio :
           entry.text === note.inferredMarker && Math.abs(entry.y - note.baseline) <= note.textHeight * 0.8));
       const highlightedEntries = marker && !textEntries.includes(marker) ? [marker, ...textEntries] : textEntries;
-      if (text.length >= 3) result.push({ ...note, markerItemIndex: marker ? items.indexOf(marker.item) : -1, text, endPageNumber: pageNumber, endColumnIndex: column.index,
-        highlightRegions: highlightRegions(highlightedEntries, viewport, pageNumber),
-        continues: !next && textEntries.at(-1)?.yRatio >= 0.88 &&
-          ((note.hangingMargin === undefined && !note.scannedSmallBlock) || !/[.!?]["')\]]?$/.test(text)) });
+      if (text.length >= 3) {
+      let fullText = text;
+      let regions = highlightRegions(highlightedEntries, viewport, pageNumber);
+      // PDF.js can assign larger text heights to wrapped lines. Repair a
+      // truncated final note without crossing the page counter or next note.
+      if (!next && layout.length === 1 && note.yRatio >= 0.65 && textEntries.length <= 2 && marker) {
+        const body = textEntries.find((entry) => entry !== marker && /[A-Za-z]/.test(entry.text));
+        const recovered = body && fallbackFootnoteParagraph(items, viewport,
+          marker.item, body.item, note.number, pageNumber);
+        if (recovered && recovered.text.length > fullText.length &&
+          recovered.highlightRegions.length > regions.length) {
+          fullText = recovered.text;
+          regions = recovered.highlightRegions;
+        }
+      }
+      const reachedBottom = textEntries.at(-1)?.yRatio >= 0.88 ||
+        (fullText !== text && regions.some((region) => region.top + region.height >= 0.88));
+      result.push({ ...note, markerItemIndex: marker ? items.indexOf(marker.item) : -1,
+        text: fullText, endPageNumber: pageNumber, endColumnIndex: column.index,
+        highlightRegions: regions,
+        continues: !next && reachedBottom &&
+          ((note.hangingMargin === undefined && !note.scannedSmallBlock) || !/[.!?]["')\\]]?$/.test(fullText)) });
+    }
     }
   }
   return result;

tests/footnote-fallback-wrap.test.mjs

@@ -0,0 +1,61 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+import { candidateForPage, footnotesForPage } from "../src/viewer/navigation/footnote-index.js";
+
+// A condensed text-layer reproduction of NBER w9126, printed page 19:
+// footnote 19 wraps to two hanging lines and a printed page counter follows.
+const viewport = {
+  width: 612, height: 792,
+  convertToViewportPoint(x, y) { return [x, 792 - y]; },
+};
+
+function line(text, x, y, width, height = 11) {
+  return { str: text, width, height, transform: [1, 0, 0, height, x, 792 - y] };
+}
+
+test("fallback footnote highlights every wrapped line, excluding the prior note and page number", () => {
+  const items = [
+    line("18 The miscellaneous category is omitted.", 90, 615, 275),
+    line("from the regressions.", 71, 629, 140),
+    line("19 Two firms reached agreement before the annual", 90, 652, 420),
+    line("meeting; the statistical analysis is unchanged.", 71, 666, 410),
+    line("The indicator remains one or zero.", 71, 680, 295),
+    line("19", 301, 733, 12, 12),
+  ];
+  const note = candidateForPage(items, viewport, 19, 19, 19);
+  assert.ok(note);
+  assert.equal(note.highlightRegions.length, 3);
+  assert.match(note.text, /statistical analysis is unchanged/);
+  assert.match(note.text, /remains one or zero/);
+  assert.doesNotMatch(note.text, /miscellaneous|regressions/);
+  assert.ok(note.highlightRegions.every((region) => region.top > 0.8 && region.top < 0.9));
+});
+
+test("fallback footnote stops before an adjacent numbered note", () => {
+  const items = [
+    line("19 First note spans", 90, 652, 250),
+    line("another line of text.", 71, 666, 210),
+    line("20 Next footnote starts here.", 90, 681, 320),
+  ];
+  const note = candidateForPage(items, viewport, 19, 19, 19);
+  assert.ok(note);
+  assert.equal(note.highlightRegions.length, 2);
+  assert.doesNotMatch(note.text, /Next footnote/);
+});
+
+test("indexed footnote recovers wrapped lines with different PDF text heights", () => {
+  const items = [
+    line("A representative paragraph above the notes.", 71, 220, 400, 16),
+    line("19", 91, 647, 12, 8),
+    line("Two firms agreed before the annual meeting;", 104, 652, 415, 11),
+    line("the analysis remains unchanged for the sample.", 71, 667, 432, 14),
+    line("The proxy-fight indicator stays one or zero.", 71, 683, 395, 14),
+    line("19", 301, 733, 12, 14),
+  ];
+  const note = footnotesForPage(items, viewport, 19).find((entry) => entry.number === 19);
+  assert.ok(note);
+  assert.match(note.text, /analysis remains unchanged/);
+  assert.match(note.text, /indicator stays one or zero/);
+  assert.ok(note.highlightRegions.length >= 3);
+  assert.doesNotMatch(note.text, /representative paragraph/);
+});