JabRef · damgam0288 · Nov 11, 2024 · Nov 11, 2024 · Nov 11, 2024 · Nov 11, 2024
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -45,6 +45,7 @@ Note that this project **does not** adhere to [Semantic Versioning](https://semv
 - We added a search bar for filtering keyboard shortcuts. [#11686](https://github.com/JabRef/jabref/issues/11686)
 - By double clicking on a local citation in the Citation Relations Tab you can now jump the linked entry. [#11955](https://github.com/JabRef/jabref/pull/11955)
 - We use the menu icon for background tasks as a progress indicator to visualise an import's progress when dragging and dropping several PDF files into the main table. [#12072](https://github.com/JabRef/jabref/pull/12072)
+- We added the ability for users to display a cover image in the preview panel of the entry editor for book, in-book and booklet citations [#10120](https://github.com/JabRef/jabref/issues/10120)
- We added the ability for users to display a cover image in the preview panel of the entry editor for book, in-book and booklet citations [#10120](https://github.com/JabRef/jabref/issues/10120)
+- We added the ability for users to display a cover image in the preview panel of the entry editor for book, in-book and booklet citations. [#10120](https://github.com/JabRef/jabref/issues/10120)
- We added the ability for users to display a cover image in the preview panel of the entry editor for book, in-book and booklet citations [#10120](https://github.com/JabRef/jabref/issues/10120)
+- We added the ability for users to display a cover image in the preview panel of the entry editor for book, in-book and booklet citations. [#10120](https://github.com/JabRef/jabref/issues/10120)
 
 ### Changed
 

diff --git a/src/main/java/org/jabref/gui/preview/PreviewViewer.java b/src/main/java/org/jabref/gui/preview/PreviewViewer.java
@@ -218,14 +218,28 @@ private void setPreviewText(String text) {
         layoutText = """
                 <html>
                     <body id="previewBody">
-                        <div id="content"> %s </div>
+                        <div style="display: flex;">
+                            <div id="content" style="flex: 1;">
+                                %s
+                            </div>
+                            <div id="bookCover" style="flex: 1;">
+                                <img src="%s" style="width: auto; height: 100vh;" align="right">
+                            </div>
+                        </div>
                     </body>
                 </html>
-                """.formatted(text);
+                """.formatted(text, getBookCoverURI());
         highlightLayoutText();
         this.setHvalue(0);
     }
 
+    private String getBookCoverURI() {
+        return entry
+                .flatMap(e -> e.getCoverImageFile()
+                .map(file -> "file:///" + file.getLink()))
+                .orElse("");
+    }
+
     private void highlightLayoutText() {
         if (layoutText == null) {
             return;

diff --git a/src/main/java/org/jabref/model/entry/BibEntry.java b/src/main/java/org/jabref/model/entry/BibEntry.java
@@ -55,6 +55,7 @@
 import org.jspecify.annotations.Nullable;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import scala.annotation.meta.field;
 
 /**
  * Represents a Bib(La)TeX entry, which can be BibTeX or BibLaTeX.
@@ -99,6 +100,10 @@
 public class BibEntry implements Cloneable {
 
     public static final EntryType DEFAULT_TYPE = StandardEntryType.Misc;
+
+    private static final List<EntryType> COVERABLE_TYPES = List.of(StandardEntryType.Book, StandardEntryType.InBook, StandardEntryType.Booklet);
+    private static final String COVER_TAG = "cover";
+
     private static final Logger LOGGER = LoggerFactory.getLogger(BibEntry.class);
     private final SharedBibEntryData sharedBibEntryData;
 
@@ -1124,6 +1129,26 @@ public Optional<FieldChange> addFiles(List<LinkedFile> filesToAdd) {
         currentFiles.addAll(filesToAdd);
         return setFiles(currentFiles);
     }
+
+    /**
+     * @return <code>LinkedFile</code> that contains the cover image
+     * if the <code>BibEntry</code> is a Book or other <code>COVERABLE_TYPES</code>
+     */
+    public Optional<LinkedFile> getCoverImageFile() {
+        if (!isCoverable()) {
+            return Optional.empty();
+        }
+
+        for (LinkedFile file : getFiles()) {
+            if (file.getDescription().equalsIgnoreCase(COVER_TAG)) {
+                if (file.isImage()) {
+                    return Optional.of(file);
+                }
+            }
+        }
+
+        return Optional.empty();
+    }
     // endregion
 
     /**
@@ -1156,7 +1181,8 @@ public Optional<Month> getMonth() {
         return getFieldOrAlias(StandardField.MONTH).flatMap(Month::parse);
     }
 
-    public OptionalBinding<String> getFieldBinding(Field field) {
+    public OptionalBinding<String> getFieldBinding(Field
+        field) {
         if ((field == InternalField.TYPE_HEADER) || (field == InternalField.OBSOLETE_TYPE_HEADER)) {
             return EasyBind.wrapNullable(type).mapOpt(EntryType::getDisplayName);
         }
@@ -1253,4 +1279,11 @@ public boolean isEmpty() {
         }
         return StandardField.AUTOMATIC_FIELDS.containsAll(this.getFields());
     }
+
+    /**
+     * @return <code>true</code> if this entry's <code>type</code> is a Book or one of <code>COVERABLE_TYPES</code>
+     */
+    private boolean isCoverable() {
+        return COVERABLE_TYPES.contains(this.type.get());
+    }
 }
diff --git a/src/main/java/org/jabref/model/entry/LinkedFile.java b/src/main/java/org/jabref/model/entry/LinkedFile.java
@@ -8,6 +8,7 @@
 import java.nio.file.Files;
 import java.nio.file.InvalidPathException;
 import java.nio.file.Path;
+import java.util.ArrayList;
 import java.util.List;
 import java.util.Objects;
 import java.util.Optional;
@@ -40,6 +41,8 @@ public class LinkedFile implements Serializable {
 
     private static final LinkedFile NULL_OBJECT = new LinkedFile("", Path.of(""), "");
 
+    private static final List<String> IMAGE_EXTENSIONS = new ArrayList<>(List.of("jpeg", "jpg", "png", "gif"));
+
     // We have to mark these properties as transient because they can't be serialized directly
     private transient StringProperty description = new SimpleStringProperty();
     private transient StringProperty link = new SimpleStringProperty();
@@ -220,6 +223,10 @@ public boolean isOnlineLink() {
         return isOnlineLink(link.get());
     }
 
+    public boolean isImage() {
+        return IMAGE_EXTENSIONS.stream().anyMatch(getFileType().toLowerCase()::contains);
+    }
+
     public Optional<Path> findIn(BibDatabaseContext databaseContext, FilePreferences filePreferences) {
         List<Path> dirs = databaseContext.getFileDirectories(filePreferences);
         return findIn(dirs);

diff --git a/src/test/java/org/jabref/model/entry/BibEntryTest.java b/src/test/java/org/jabref/model/entry/BibEntryTest.java
@@ -2,6 +2,7 @@
 
 import java.net.URI;
 import java.nio.file.Path;
+import java.nio.file.Paths;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
@@ -813,6 +814,100 @@ void mergeEntriesWithOverlapAndPriorityGivenToOverlappingField() {
         assertEquals(expected.getFields(), copyEntry.getFields());
     }
 
+    @Test
+    void getCoverImageReturnsEmptyIfNoFiles() {
+        entry = new BibEntry(StandardEntryType.Book).withField(StandardField.AUTHOR, "value");
+        assertEquals(Optional.empty(), entry.getCoverImageFile());
+    }
+
+    @Test
+    void getCoverImageReturnsEmptyIfNoImageFiles() {
+        LinkedFile pdf = new LinkedFile("", Paths.get("Baldoni2002.pdf").toAbsolutePath().toString(), "pdf");
+        LinkedFile markdown = new LinkedFile("", "readme.md", "md");
+        entry = new BibEntry(StandardEntryType.Book).withField(StandardField.AUTHOR, "value");
+
+        entry.addFile(markdown);
+        entry.addFile(pdf);
+
+        assertEquals(Optional.empty(), entry.getCoverImageFile());
+    }
+
+    @Test
+    void getCoverImageReturnsEmptyIfEntryIsNotCoverable() {
+        entry = new BibEntry(StandardEntryType.Proceedings).withField(StandardField.AUTHOR, "value");
+        assertEquals(Optional.empty(), entry.getCoverImageFile());
+
+        entry = new BibEntry(StandardEntryType.Dataset).withField(StandardField.AUTHOR, "value");
+        assertEquals(Optional.empty(), entry.getCoverImageFile());
+
+        entry = new BibEntry(StandardEntryType.Software).withField(StandardField.AUTHOR, "value");
+        assertEquals(Optional.empty(), entry.getCoverImageFile());
+    }
+
+    @Test
+    void getCoverImageDoesNotReturnImagesWithoutCoverDescription() {
+        LinkedFile cover1 = new LinkedFile("", Paths.get("JabRef-icon-128.png"), "png");
+        LinkedFile cover2 = new LinkedFile("", Paths.get("JabRef-icon-64.png"), "png");
+        LinkedFile cover3 = new LinkedFile("", Paths.get("JabRef-icon-32.png"), "png");
+        entry = new BibEntry(StandardEntryType.Book).withField(StandardField.AUTHOR, "value");
+
+        entry.addFile(cover1);
+        entry.addFile(cover2);
+        entry.addFile(cover3);
+
+        assertNotEquals(Optional.of(cover1), entry.getCoverImageFile());
+        assertNotEquals(Optional.of(cover2), entry.getCoverImageFile());
+        assertNotEquals(Optional.of(cover3), entry.getCoverImageFile());
+    }
+
+    @Test
+    void getCoverImageDoesNotReturnDocumentsWithCoverDescription() {
+        LinkedFile pdf = new LinkedFile("cover", Paths.get("Baldoni2002.pdf"), "pdf");
+        LinkedFile md = new LinkedFile("cover", Paths.get("readme.md"), "md");
+        entry = new BibEntry(StandardEntryType.Book).withField(StandardField.AUTHOR, "value");
+
+        entry.addFile(pdf);
+        entry.addFile(md);
+
+        assertNotEquals(Optional.of(md), entry.getCoverImageFile());
+        assertNotEquals(Optional.of(pdf), entry.getCoverImageFile());
+    }
+
+    @Test
+    void getCoverImageReturnsCorrectImage() {
+        LinkedFile cover1 = new LinkedFile("", Paths.get("JabRef-icon-128.png"), "png");
+        LinkedFile cover2 = new LinkedFile("", Paths.get("JabRef-icon-64.png"), "png");
+        LinkedFile cover3 = new LinkedFile("cover", Paths.get("JabRef-icon-32.png"), "png");
+        BibEntry entry = new BibEntry(StandardEntryType.Book).withField(StandardField.AUTHOR, "value");
+
+        entry.addFile(cover1);
+        entry.addFile(cover2);
+        entry.addFile(cover3);
+
+        assertEquals(Optional.of(cover3), entry.getCoverImageFile());
+    }
+
+    @Test
+    void getCoverImageUpdatesWithChangeToDescription() {
+        List<LinkedFile> files = new ArrayList<>();
+
+        files.add(new LinkedFile("cover", Paths.get("JabRef-icon-128.png"), "png"));
+        files.add(new LinkedFile("", Paths.get("JabRef-icon-64.png"), "png"));
+        LinkedFile cover1 = files.get(0);
+        LinkedFile cover2 = files.get(1);
+
+        BibEntry entry = new BibEntry(StandardEntryType.Book).withField(StandardField.AUTHOR, "value");
+        entry.setFiles(files);
+
+        assertEquals(Optional.of(cover1), entry.getCoverImageFile());
+
+        cover1.setDescription("");
+        cover2.setDescription("cover");
+        entry.setFiles(files);
+
+        assertEquals(Optional.of(cover2), entry.getCoverImageFile());
+    }
+
     public static Stream<BibEntry> isEmpty() {
         return Stream.of(
                 new BibEntry(),