Refactor redaction services and utilities for improved readability and maintainability

- Adjusted indentation and formatting across multiple files for consistency.
- Improved imports ordering in utility classes for better organization.
- Enhanced `performTextReplacementAggressive` method with multi-sweep logic to handle residual text more effectively.
- Added helper methods for verifying document text targets to streamline aggressive redaction.
- Simplified logic and formatting in `RedactionService` and related classes.

Signed-off-by: Balázs Szücs <bszucs1209@gmail.com>

app/core/src/main/java/stirling/software/SPDF/service/RedactionService.java

@@ -65,6 +65,7 @@ public class RedactionService {
     private static final int FONT_SCALE_FACTOR = 1000;
     private static final Set<String> TEXT_SHOWING_OPERATORS = Set.of("Tj", "TJ", "'", "\"");
     private static final COSString EMPTY_COS_STRING = new COSString("");
+    private static final int MAX_SWEEPS = 3;
     private static final ThreadLocal<Boolean> AGGRESSIVE_MODE =
             ThreadLocal.withInitial(() -> Boolean.FALSE);
     private static final ThreadLocal<Map<Integer, List<AggressiveSegMatch>>> AGGR_SEG_MATCHES =
@@ -268,6 +269,26 @@ public class RedactionService {
         return false;
     }
 
+    private static boolean documentStillContainsTargets(
+            PDDocument document,
+            Set<String> targetWords,
+            boolean useRegex,
+            boolean wholeWordSearch) {
+        try {
+            int idx = -1;
+            for (int i = 0; i < document.getNumberOfPages(); i++) {
+                idx++;
+                if (pageStillContainsTargets(
+                        document, idx, targetWords, useRegex, wholeWordSearch)) {
+                    return true;
+                }
+            }
+        } catch (Exception ignored) {
+            return true;
+        }
+        return false;
+    }
+
     public static Map<Integer, List<PDFText>> findTextToRedact(
             PDDocument document, String[] listOfText, boolean useRegex, boolean wholeWordSearch) {
         Map<Integer, List<PDFText>> allFoundTextsByPage = new HashMap<>();
@@ -809,6 +830,8 @@ public class RedactionService {
                         .collect(Collectors.toSet());
         AGGRESSIVE_MODE.set(Boolean.TRUE);
         try {
+            for (int sweep = 0; sweep < MAX_SWEEPS; sweep++) {
+                boolean anyResidual = false;
                 int pageIndex = -1;
                 for (PDPage page : document.getPages()) {
                     pageIndex++;
@@ -816,7 +839,11 @@ public class RedactionService {
                         AGGR_SEG_MATCHES.remove();
                         List<Object> filtered =
                                 createTokensWithoutTargetText(
-                            document, page, allSearchTerms, useRegex, wholeWordSearchBool);
+                                        document,
+                                        page,
+                                        allSearchTerms,
+                                        useRegex,
+                                        wholeWordSearchBool);
                         writeFilteredContentStream(document, page, filtered);
                         boolean residual =
                                 pageStillContainsTargets(
@@ -826,6 +853,7 @@ public class RedactionService {
                                         useRegex,
                                         wholeWordSearchBool);
                         if (residual) {
+                            anyResidual = true;
                             try {
                                 var sem = wipeAllSemanticTextInTokens(filtered);
                                 filtered = sem.tokens;
@@ -842,6 +870,16 @@ public class RedactionService {
                     } catch (Exception ignored) {
                     }
                 }
+                // If no residuals detected in this sweep, stop early
+                if (!anyResidual) {
+                    break;
+                }
+                // As a safety, if nothing left in the doc, stop
+                if (!documentStillContainsTargets(
+                        document, allSearchTerms, useRegex, wholeWordSearchBool)) {
+                    break;
+                }
+            }
         } finally {
             AGGRESSIVE_MODE.remove();
         }
@@ -862,12 +900,19 @@ public class RedactionService {
                             .map(String::trim)
                             .filter(s -> !s.isEmpty())
                             .collect(Collectors.toSet());
+            for (int sweep = 0; sweep < MAX_SWEEPS; sweep++) {
                 for (PDPage page : document.getPages()) {
                     List<Object> filtered =
                             createTokensWithoutTargetText(
                                     document, page, allSearchTerms, useRegex, wholeWordSearchBool);
                     writeFilteredContentStream(document, page, filtered);
                 }
+                // Stop early if nothing remains
+                if (!documentStillContainsTargets(
+                        document, allSearchTerms, useRegex, wholeWordSearchBool)) {
+                    break;
+                }
+            }
             return false;
         } catch (Exception e) {
             return true;
@@ -1473,7 +1518,8 @@ public class RedactionService {
                                 String originalPart =
                                         originalText.substring(
                                                 redactionStartInString, redactionEndInString);
-                                if (!Boolean.TRUE.equals(AGGRESSIVE_MODE.get()) && segment.getFont() != null
+                                if (!Boolean.TRUE.equals(AGGRESSIVE_MODE.get())
+                                        && segment.getFont() != null
                                         && !TextEncodingHelper.isTextSegmentRemovable(
                                                 segment.getFont(), originalPart)) {
                                     continue;
@@ -1514,7 +1560,10 @@ public class RedactionService {
                     }
                     String modifiedString = newText.toString();
                     newArray.add(new COSString(modifiedString));
-                    if (!Boolean.TRUE.equals(AGGRESSIVE_MODE.get()) && modified && segment.getFont() != null && segment.getFontSize() > 0) {
+                    if (!Boolean.TRUE.equals(AGGRESSIVE_MODE.get())
+                            && modified
+                            && segment.getFont() != null
+                            && segment.getFontSize() > 0) {
                         try {
                             float originalWidth =
                                     safeGetStringWidth(segment.getFont(), originalText)
@@ -1847,8 +1896,7 @@ public class RedactionService {
         private PDFont font = null;
         private float fontSize = 0;
 
-        public GraphicsState() {
+        public GraphicsState() {}
-        }
     }
 
     @Data

app/core/src/main/java/stirling/software/SPDF/utils/text/TextDecodingHelper.java

@@ -1,17 +1,17 @@
 package stirling.software.SPDF.utils.text;
 
-import lombok.experimental.UtilityClass;
-import org.apache.pdfbox.cos.COSString;
-import org.apache.pdfbox.pdmodel.font.PDFont;
-import org.apache.pdfbox.pdmodel.font.PDType0Font;
-
-import lombok.extern.slf4j.Slf4j;
-
 import java.nio.ByteBuffer;
 import java.nio.CharBuffer;
 import java.nio.charset.CharsetDecoder;
 import java.nio.charset.StandardCharsets;
 
+import org.apache.pdfbox.cos.COSString;
+import org.apache.pdfbox.pdmodel.font.PDFont;
+import org.apache.pdfbox.pdmodel.font.PDType0Font;
+
+import lombok.experimental.UtilityClass;
+import lombok.extern.slf4j.Slf4j;
+
 @Slf4j
 @UtilityClass
 public class TextDecodingHelper {
@@ -89,8 +89,7 @@ public class TextDecodingHelper {
         } catch (Exception ignored) {
         }
 
-        if (charStr == null
+        if (charStr == null && font instanceof PDType0Font type0Font) {
-            && font instanceof PDType0Font type0Font) {
             try {
                 int cid = (bytes.length > 1) ? ((bytes[0] & 0xFF) << 8) | (bytes[1] & 0xFF) : code;
                 charStr = type0Font.toUnicode(cid);
@@ -143,8 +142,7 @@ public class TextDecodingHelper {
             try {
                 if (bytes.length >= 2) {
                     ByteBuffer buffer = ByteBuffer.wrap(bytes);
-                    CharsetDecoder decoder =
+                    CharsetDecoder decoder = StandardCharsets.UTF_16BE.newDecoder();
-                        StandardCharsets.UTF_16BE.newDecoder();
                     CharBuffer charBuffer = decoder.decode(buffer);
                     return charBuffer.toString();
                 }

app/core/src/main/java/stirling/software/SPDF/utils/text/TextEncodingHelper.java

@@ -2,12 +2,12 @@ package stirling.software.SPDF.utils.text;
 
 import java.io.IOException;
 
-import lombok.experimental.UtilityClass;
 import org.apache.pdfbox.pdmodel.font.PDFont;
 import org.apache.pdfbox.pdmodel.font.PDSimpleFont;
 import org.apache.pdfbox.pdmodel.font.encoding.DictionaryEncoding;
 import org.apache.pdfbox.pdmodel.font.encoding.Encoding;
 
+import lombok.experimental.UtilityClass;
 import lombok.extern.slf4j.Slf4j;
 
 @Slf4j

app/core/src/main/java/stirling/software/SPDF/utils/text/TextFinderUtils.java

@@ -5,13 +5,13 @@ import java.util.List;
 import java.util.Set;
 import java.util.regex.Pattern;
 
-import lombok.experimental.UtilityClass;
 import org.apache.pdfbox.pdmodel.PDPage;
 import org.apache.pdfbox.pdmodel.PDResources;
-
-import lombok.extern.slf4j.Slf4j;
 import org.apache.pdfbox.pdmodel.font.PDFont;
 
+import lombok.experimental.UtilityClass;
+import lombok.extern.slf4j.Slf4j;
+
 @Slf4j
 @UtilityClass
 public class TextFinderUtils {

app/core/src/main/java/stirling/software/SPDF/utils/text/WidthCalculator.java

@@ -1,9 +1,9 @@
 package stirling.software.SPDF.utils.text;
 
-import lombok.experimental.UtilityClass;
 import org.apache.pdfbox.pdmodel.common.PDRectangle;
 import org.apache.pdfbox.pdmodel.font.PDFont;
 
+import lombok.experimental.UtilityClass;
 import lombok.extern.slf4j.Slf4j;
 
 @Slf4j
@@ -44,8 +44,7 @@ public class WidthCalculator {
         }
     }
 
-    private float calculateWidthWithCharacterIteration(
+    private float calculateWidthWithCharacterIteration(PDFont font, String text, float fontSize) {
-        PDFont font, String text, float fontSize) {
         try {
             float totalWidth = 0;