JAMES-4100 Improve Search Snippet display

mailbox/api/src/test/java/org/apache/james/mailbox/searchhighligt/SearchHighLighterContract.java

@@ -532,4 +532,43 @@ default void shouldHighLightBodyWhenHTMLBodyMatched() throws Exception {
             softly.assertThat(searchSnippets.getFirst().highlightedBody().get()).contains("<mark>barcamp</mark>");
         });
     }
+
+    @Test
+    default void highlightSearchShouldShortenGreaterThanCharacters() throws Exception {
+        MailboxSession session = session(USERNAME1);
+
+        // Given m1,m2 with m1 has body containing the searched word (contentA)
+        ComposedMessageId m1 = appendMessage(MessageManager.AppendCommand.from(
+                Message.Builder.of()
+                    .setTo("[email protected]")
+                    .setSubject("Hallo, Thx Matthieu for your help")
+                    .setBody("Start \n>>>>>>>>>> append contentA to > inbox \n>>>>>> End",
+                        StandardCharsets.UTF_8)),
+            session).getId();
+
+        ComposedMessageId m2 = appendMessage(MessageManager.AppendCommand.from(
+                Message.Builder.of()
+                    .setTo("[email protected]")
+                    .setSubject("Hallo, Thx Alex for your help")
+                    .setBody("append contentB to inbox", StandardCharsets.UTF_8)),
+            session).getId();
+
+        verifyMessageWasIndexed(2);
+
+        // When searching for the word (contentA) in the body
+        MultimailboxesSearchQuery multiMailboxSearch = MultimailboxesSearchQuery.from(SearchQuery.of(
+                SearchQuery.bodyContains("contentA")))
+            .inMailboxes(List.of(m1.getMailboxId(), m2.getMailboxId()))
+            .build();
+
+        // Then highlightSearch should return the SearchSnippet with the highlightedBody containing the word (contentA)
+        List<SearchSnippet> searchSnippets = Flux.from(testee().highlightSearch(List.of(m1.getMessageId(), m2.getMessageId()), multiMailboxSearch, session))
+            .collectList()
+            .block();
+        assertThat(searchSnippets).hasSize(1);
+        assertSoftly(softly -> {
+            softly.assertThat(searchSnippets.getFirst().messageId()).isEqualTo(m1.getMessageId());
+            softly.assertThat(searchSnippets.getFirst().highlightedBody().get()).isEqualTo("Start \n append <mark>contentA</mark> to &gt; inbox \n End");
+        });
+    }
 }

mailbox/lucene/src/main/java/org/apache/james/mailbox/lucene/search/LuceneIndexableDocument.java

@@ -195,7 +195,7 @@ public Document createMessageDocument(MailboxMessage message, MailboxSession ses
         doc.add(new TextField(BCC_FIELD, uppercase(EMailers.from(headerCollection.getBccAddressSet()).serialize()), Field.Store.YES));
 
         // index body
-        Optional<String> bodyText = mimePartExtracted.locateFirstTextBody();
+        Optional<String> bodyText = mimePartExtracted.locateFirstTextBody().map(SearchUtil::removeGreaterThanCharactersAtBeginningOfLine);
         Optional<String> bodyHtml = mimePartExtracted.locateFirstHtmlBody();
 
         bodyText.or(() -> bodyHtml)

mailbox/lucene/src/main/java/org/apache/james/mailbox/lucene/search/LuceneSearchHighlighter.java

@@ -57,6 +57,7 @@
 import org.apache.lucene.search.highlight.Formatter;
 import org.apache.lucene.search.highlight.Highlighter;
 import org.apache.lucene.search.highlight.QueryScorer;
+import org.apache.lucene.search.highlight.SimpleHTMLEncoder;
 import org.apache.lucene.search.highlight.SimpleHTMLFormatter;
 import org.apache.lucene.search.highlight.SimpleSpanFragmenter;
 
@@ -126,6 +127,7 @@ private Highlighter highlighter(SearchQuery searchQuery) {
         Query query = buildQueryFromSearchQuery(searchQuery);
         QueryScorer scorer = new QueryScorer(query);
         Highlighter highlighter = new Highlighter(formatter, scorer);
+        highlighter.setEncoder(new SimpleHTMLEncoder());
         highlighter.setTextFragmenter(new SimpleSpanFragmenter(scorer, configuration.fragmentSize()));
         return highlighter;
     }

mailbox/opensearch/src/main/java/org/apache/james/mailbox/opensearch/json/IndexableMessage.java

@@ -135,7 +135,7 @@ private Mono<IndexableMessage> instantiateIndexedMessage() throws IOException, M
                 .asMimePart(textExtractor)
                 .map(parsingResult -> {
 
-                    Optional<String> bodyText = parsingResult.locateFirstTextBody();
+                    Optional<String> bodyText = parsingResult.locateFirstTextBody().map(SearchUtil::removeGreaterThanCharactersAtBeginningOfLine);
                     Optional<String> bodyHtml = parsingResult.locateFirstHtmlBody();
 
                     boolean hasAttachment = MessageAttachmentMetadata.hasNonInlinedAttachment(message.getAttachments());

mailbox/store/src/main/java/org/apache/james/mailbox/store/search/SearchUtil.java

@@ -473,5 +473,22 @@ public boolean test(MessageId input) {
         };
     }
 
+    public static String removeGreaterThanCharactersAtBeginningOfLine(String text) {
+        StringBuilder result = new StringBuilder();
+        boolean isNewLine = false;
 
+        for (int i = 0; i < text.length(); i++) {
+            char current = text.charAt(i);
+
+            if (current == '\n') {
+                isNewLine = true;
+                result.append(current);
+            } else if (!isNewLine || current != '>') {
+                result.append(current);
+                isNewLine = false;
+            }
+        }
+
+        return result.toString();
+    }
 }