From 41832f9897f8ef7221b0a6a00dc6c4588805bdc5 Mon Sep 17 00:00:00 2001
From: Thomas Beyer <thomas.beyer@iqser.com>
Date: Mon, 20 Mar 2023 15:04:37 +0100
Subject: [PATCH] RED-4875 - first implementation of hasInvisibleText()

---
 .../InvisibleElementRemovalService.java       | 20 ++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/src/main/java/com/iqser/red/pdftronlogic/commons/InvisibleElementRemovalService.java b/src/main/java/com/iqser/red/pdftronlogic/commons/InvisibleElementRemovalService.java
index edb9b29..8851e0d 100644
--- a/src/main/java/com/iqser/red/pdftronlogic/commons/InvisibleElementRemovalService.java
+++ b/src/main/java/com/iqser/red/pdftronlogic/commons/InvisibleElementRemovalService.java
@@ -118,6 +118,8 @@ public class InvisibleElementRemovalService {
         log.info("Finished removing invisible Elements");
     }
 
+
+
     private void removeClippedElementsAndInvisibleTextAndRememberOverlappedElements(Page page,
                                                                                     ElementWriter writer,
                                                                                     InvisibleElementRemovalContext context) throws PDFNetException {
@@ -150,7 +152,23 @@ public class InvisibleElementRemovalService {
             }
     }
 
-
+    @SneakyThrows
+    public boolean hasInvisibleText(PDFDoc pdfDoc) {
+        ElementReader reader = new ElementReader();
+        for (PageIterator iterator = pdfDoc.getPageIterator(); iterator.hasNext(); ) {
+            Page page = iterator.next();
+            for (Element element = reader.next(); element != null; element = reader.next()) {
+                if (element.getType() == Element.e_text) {
+                    GState gState = element.getGState();
+                    boolean isTextVisible = isTextRenderedVisibly(gState);
+                    if (!isTextVisible) {
+                        return true;
+                    }
+                }
+            }
+        }
+        return false;
+    }
     private void processImages(Element imageElement, ElementWriter writer, InvisibleElementRemovalContext context) throws PDFNetException {
 
         Rect rect = imageElement.getBBox();