Lectures: Add hide/show functionality to PDF Preview Component

src/main/java/de/tum/cit/aet/artemis/core/service/FilePathService.java

@@ -146,6 +146,10 @@ public static Path actualPathForPublicPath(URI publicPath) {
 
     private static Path actualPathForPublicAttachmentUnitFilePath(URI publicPath, String filename) {
         Path path = Path.of(publicPath.getPath());
+        if (publicPath.toString().contains("/student")) {
+            String attachmentUnitId = path.getName(4).toString();
+            return getAttachmentUnitFilePath().resolve(Path.of(attachmentUnitId, "student", filename));
+        }
         if (!publicPath.toString().contains("/slide")) {
             String attachmentUnitId = path.getName(4).toString();
             return getAttachmentUnitFilePath().resolve(Path.of(attachmentUnitId, filename));
@@ -244,6 +248,9 @@ public static URI publicPathForActualPath(Path path, @Nullable Long entityId) {
     }
 
     private static URI publicPathForActualAttachmentUnitFilePath(Path path, String filename, String id) {
+        if (path.toString().contains("/student")) {
+            return URI.create("/api/files/attachments/attachment-unit/" + id + "/student/" + filename);
+        }
         if (!path.toString().contains("/slide")) {
             return URI.create("/api/files/attachments/attachment-unit/" + id + "/" + filename);
         }

src/main/java/de/tum/cit/aet/artemis/core/web/FileResource.java

@@ -75,7 +75,6 @@
 import de.tum.cit.aet.artemis.lecture.repository.AttachmentRepository;
 import de.tum.cit.aet.artemis.lecture.repository.AttachmentUnitRepository;
 import de.tum.cit.aet.artemis.lecture.repository.LectureRepository;
-import de.tum.cit.aet.artemis.lecture.repository.SlideRepository;
 import de.tum.cit.aet.artemis.lecture.service.LectureUnitService;
 import de.tum.cit.aet.artemis.programming.domain.ProgrammingLanguage;
 import de.tum.cit.aet.artemis.programming.domain.ProjectType;
@@ -104,8 +103,6 @@ public class FileResource {
 
     private final AttachmentUnitRepository attachmentUnitRepository;
 
-    private final SlideRepository slideRepository;
-
     private final FileUploadSubmissionRepository fileUploadSubmissionRepository;
 
     private final AttachmentRepository attachmentRepository;
@@ -126,7 +123,7 @@ public class FileResource {
 
     private final LectureUnitService lectureUnitService;
 
-    public FileResource(SlideRepository slideRepository, AuthorizationCheckService authorizationCheckService, FileService fileService, ResourceLoaderService resourceLoaderService,
+    public FileResource(AuthorizationCheckService authorizationCheckService, FileService fileService, ResourceLoaderService resourceLoaderService,
             LectureRepository lectureRepository, FileUploadSubmissionRepository fileUploadSubmissionRepository, AttachmentRepository attachmentRepository,
             AttachmentUnitRepository attachmentUnitRepository, AuthorizationCheckService authCheckService, UserRepository userRepository, ExamUserRepository examUserRepository,
             QuizQuestionRepository quizQuestionRepository, DragItemRepository dragItemRepository, CourseRepository courseRepository, LectureUnitService lectureUnitService) {
@@ -140,7 +137,6 @@ public FileResource(SlideRepository slideRepository, AuthorizationCheckService a
         this.userRepository = userRepository;
         this.authorizationCheckService = authorizationCheckService;
         this.examUserRepository = examUserRepository;
-        this.slideRepository = slideRepository;
         this.quizQuestionRepository = quizQuestionRepository;
         this.dragItemRepository = dragItemRepository;
         this.courseRepository = courseRepository;
@@ -476,7 +472,7 @@ public ResponseEntity<byte[]> getLecturePdfAttachmentsMerged(@PathVariable Long
      * @return The requested file, 403 if the logged-in user is not allowed to access it, or 404 if the file doesn't exist
      */
     @GetMapping("files/attachments/attachment-unit/{attachmentUnitId}/*")
-    @EnforceAtLeastStudent
+    @EnforceAtLeastTutor
     public ResponseEntity<byte[]> getAttachmentUnitAttachment(@PathVariable Long attachmentUnitId) {
         log.debug("REST request to get the file for attachment unit {} for students", attachmentUnitId);
         AttachmentUnit attachmentUnit = attachmentUnitRepository.findByIdElseThrow(attachmentUnitId);
@@ -547,8 +543,10 @@ public ResponseEntity<byte[]> getAttachmentUnitAttachmentSlide(@PathVariable Lon
 
         checkAttachmentAuthorizationOrThrow(course, attachment);
 
-        Slide slide = slideRepository.findSlideByAttachmentUnitIdAndSlideNumber(attachmentUnitId, Integer.parseInt(slideNumber));
-        String directoryPath = slide.getSlideImagePath();
+        // Get the all the slides without hidden slides and get the visible slide by slide index
+        Slide visibleSlide = attachmentUnit.getSlides().stream().filter(slide -> slide.getHidden() == null).toList().get(Integer.parseInt(slideNumber) - 1);
+
+        String directoryPath = visibleSlide.getSlideImagePath();
 
         // Use regular expression to match and extract the file name with ".png" format
         Pattern pattern = Pattern.compile(".*/([^/]+\\.png)$");
@@ -557,14 +555,38 @@ public ResponseEntity<byte[]> getAttachmentUnitAttachmentSlide(@PathVariable Lon
         if (matcher.matches()) {
             String fileName = matcher.group(1);
             return buildFileResponse(
-                    FilePathService.getAttachmentUnitFilePath().resolve(Path.of(attachmentUnit.getId().toString(), "slide", String.valueOf(slide.getSlideNumber()))), fileName,
-                    true);
+                    FilePathService.getAttachmentUnitFilePath().resolve(Path.of(attachmentUnit.getId().toString(), "slide", String.valueOf(visibleSlide.getSlideNumber()))),
+                    fileName, false);
         }
         else {
             throw new EntityNotFoundException("Slide", slideNumber);
         }
     }
 
+    /**
+     * GET files/attachments/attachment-unit/{attachmentUnitId}/student/* : Get the student version of attachment unit by attachment unit id
+     *
+     * @param attachmentUnitId ID of the attachment unit, the student version belongs to
+     * @return The requested file, 403 if the logged-in user is not allowed to access it, or 404 if the file doesn't exist
+     */
+    @GetMapping("files/attachments/attachment-unit/{attachmentUnitId}/student/*")
+    @EnforceAtLeastStudent
+    public ResponseEntity<byte[]> getAttachmentUnitStudentVersion(@PathVariable Long attachmentUnitId) {
+        log.debug("REST request to get the student version of attachment Unit : {}", attachmentUnitId);
+        AttachmentUnit attachmentUnit = attachmentUnitRepository.findByIdElseThrow(attachmentUnitId);
+        Attachment attachment = attachmentUnit.getAttachment();
+
+        // check if hidden link is available in the attachment
+        String studentVersion = attachment.getStudentVersion();
+        if (studentVersion == null) {
+            return buildFileResponse(getActualPathFromPublicPathString(attachment.getLink()), false);
+        }
+
+        String fileName = studentVersion.substring(studentVersion.lastIndexOf("/") + 1);
+
+        return buildFileResponse(FilePathService.getAttachmentUnitFilePath().resolve(Path.of(attachmentUnit.getId().toString(), "student")), fileName, false);
+    }
+
     /**
      * Builds the response with headers, body and content type for specified path containing the file name
      *

src/main/java/de/tum/cit/aet/artemis/lecture/domain/Attachment.java

@@ -61,6 +61,9 @@ public class Attachment extends DomainObject implements Serializable {
     @JoinColumn(name = "attachment_unit_id")
     private AttachmentUnit attachmentUnit;
 
+    @Column(name = "student_version")
+    private String studentVersion;
+
     // jhipster-needle-entity-add-field - JHipster will add fields here, do not remove
 
     public String getName() {
@@ -135,6 +138,14 @@ public void setAttachmentUnit(AttachmentUnit attachmentUnit) {
         this.attachmentUnit = attachmentUnit;
     }
 
+    public String getStudentVersion() {
+        return studentVersion;
+    }
+
+    public void setStudentVersion(String studentVersion) {
+        this.studentVersion = studentVersion;
+    }
+
     public Boolean isVisibleToStudents() {
         if (releaseDate == null) {  // no release date means the attachment is visible to students
             return Boolean.TRUE;

src/main/java/de/tum/cit/aet/artemis/lecture/domain/AttachmentUnit.java

@@ -28,7 +28,7 @@ public class AttachmentUnit extends LectureUnit {
     @JsonIgnoreProperties(value = "attachmentUnit", allowSetters = true)
     private Attachment attachment;
 
-    @OneToMany(mappedBy = "attachmentUnit", cascade = CascadeType.REMOVE, orphanRemoval = true, fetch = FetchType.LAZY)
+    @OneToMany(mappedBy = "attachmentUnit", cascade = CascadeType.REMOVE, orphanRemoval = true, fetch = FetchType.EAGER)
     @JsonIgnoreProperties("attachmentUnit")
     private List<Slide> slides = new ArrayList<>();
 

src/main/java/de/tum/cit/aet/artemis/lecture/domain/Slide.java

@@ -1,5 +1,7 @@
 package de.tum.cit.aet.artemis.lecture.domain;
 
+import java.util.Date;
+
 import jakarta.persistence.Column;
 import jakarta.persistence.Entity;
 import jakarta.persistence.JoinColumn;
@@ -27,6 +29,9 @@ public class Slide extends DomainObject {
     @Column(name = "slide_number")
     private int slideNumber;
 
+    @Column(name = "hidden")
+    private Date hidden;
+
     public AttachmentUnit getAttachmentUnit() {
         return attachmentUnit;
     }
@@ -50,4 +55,12 @@ public int getSlideNumber() {
     public void setSlideNumber(int slideNumber) {
         this.slideNumber = slideNumber;
     }
+
+    public Date getHidden() {
+        return hidden;
+    }
+
+    public void setHidden(Date hidden) {
+        this.hidden = hidden;
+    }
 }

src/main/java/de/tum/cit/aet/artemis/lecture/repository/SlideRepository.java

@@ -16,5 +16,4 @@
 public interface SlideRepository extends ArtemisJpaRepository<Slide, Long> {
 
     Slide findSlideByAttachmentUnitIdAndSlideNumber(Long attachmentUnitId, Integer slideNumber);
-
 }

src/main/java/de/tum/cit/aet/artemis/lecture/service/AttachmentUnitService.java

@@ -107,11 +107,13 @@ public AttachmentUnit createAttachmentUnit(AttachmentUnit attachmentUnit, Attach
      * @param updateUnit             The new attachment unit data.
      * @param updateAttachment       The new attachment data.
      * @param updateFile             The optional file.
+     * @param studentVersionFile     The student version of the original file.
      * @param keepFilename           Whether to keep the original filename or not.
+     * @param hiddenPages            The hidden pages of attachment unit.
      * @return The updated attachment unit.
      */
     public AttachmentUnit updateAttachmentUnit(AttachmentUnit existingAttachmentUnit, AttachmentUnit updateUnit, Attachment updateAttachment, MultipartFile updateFile,
-            boolean keepFilename) {
+            MultipartFile studentVersionFile, boolean keepFilename, String hiddenPages) {
         Set<CompetencyLectureUnitLink> existingCompetencyLinks = new HashSet<>(existingAttachmentUnit.getCompetencyLinks());
 
         existingAttachmentUnit.setDescription(updateUnit.getDescription());
@@ -128,6 +130,7 @@ public AttachmentUnit updateAttachmentUnit(AttachmentUnit existingAttachmentUnit
 
         updateAttachment(existingAttachment, updateAttachment, savedAttachmentUnit);
         handleFile(updateFile, existingAttachment, keepFilename, savedAttachmentUnit.getId());
+        handleStudentVersionFile(studentVersionFile, existingAttachment, savedAttachmentUnit.getId());
         final int revision = existingAttachment.getVersion() == null ? 1 : existingAttachment.getVersion() + 1;
         existingAttachment.setVersion(revision);
         Attachment savedAttachment = attachmentRepository.saveAndFlush(existingAttachment);
@@ -145,7 +148,7 @@ public AttachmentUnit updateAttachmentUnit(AttachmentUnit existingAttachmentUnit
             }
             // Split the updated file into single slides only if it is a pdf
             if (Objects.equals(FilenameUtils.getExtension(updateFile.getOriginalFilename()), "pdf")) {
-                slideSplitterService.splitAttachmentUnitIntoSingleSlides(savedAttachmentUnit);
+                slideSplitterService.splitAttachmentUnitIntoSingleSlides(savedAttachmentUnit, hiddenPages);
             }
             if (pyrisWebhookService.isPresent() && irisSettingsRepository.isPresent()) {
                 pyrisWebhookService.get().autoUpdateAttachmentUnitsInPyris(savedAttachmentUnit.getLecture().getCourse().getId(), List.of(savedAttachmentUnit));
@@ -191,6 +194,30 @@ private void handleFile(MultipartFile file, Attachment attachment, boolean keepF
         }
     }
 
+    /**
+     * Handles the student version file of an attachment, updates its reference in the database,
+     * and deletes the old version if it exists.
+     *
+     * @param studentVersionFile the new student version file to be saved
+     * @param attachment         the existing attachment
+     * @param attachmentUnitId   the id of the attachment unit
+     */
+    public void handleStudentVersionFile(MultipartFile studentVersionFile, Attachment attachment, Long attachmentUnitId) {
+        if (studentVersionFile != null) {
+            // Delete the old student version
+            if (attachment.getStudentVersion() != null) {
+                URI oldHiddenPath = URI.create(attachment.getStudentVersion());
+                fileService.schedulePathForDeletion(FilePathService.actualPathForPublicPathOrThrow(oldHiddenPath), 0);
+                this.fileService.evictCacheForPath(FilePathService.actualPathForPublicPathOrThrow(oldHiddenPath));
+            }
+
+            // Update student version of attachment
+            Path basePath = FilePathService.getAttachmentUnitFilePath().resolve(attachmentUnitId.toString());
+            Path savePath = fileService.saveFile(studentVersionFile, basePath.resolve("student"), true);
+            attachment.setStudentVersion(FilePathService.publicPathForActualPath(savePath, attachmentUnitId).toString());
+        }
+    }
+
     /**
      * If a file was provided the cache for that file gets evicted.
      *

src/main/java/de/tum/cit/aet/artemis/lecture/service/LectureService.java

@@ -30,6 +30,7 @@
 import de.tum.cit.aet.artemis.lecture.domain.ExerciseUnit;
 import de.tum.cit.aet.artemis.lecture.domain.Lecture;
 import de.tum.cit.aet.artemis.lecture.domain.LectureUnit;
+import de.tum.cit.aet.artemis.lecture.domain.Slide;
 import de.tum.cit.aet.artemis.lecture.repository.LectureRepository;
 
 @Profile(PROFILE_CORE)
@@ -186,4 +187,18 @@ public void ingestLecturesInPyris(Set<Lecture> lectures) {
             }
         }
     }
+
+    /**
+     * Filters the slides of all attachment units in a given lecture to exclude slides where `hidden` is not null.
+     *
+     * @param lectureWithAttachmentUnits the lecture containing attachment units
+     */
+    public void filterHiddenPagesOfAttachmentUnits(Lecture lectureWithAttachmentUnits) {
+        for (LectureUnit unit : lectureWithAttachmentUnits.getLectureUnits()) {
+            if (unit instanceof AttachmentUnit attachmentUnit) {
+                List<Slide> filteredSlides = attachmentUnit.getSlides().stream().filter(slide -> slide.getHidden() == null).toList();
+                attachmentUnit.setSlides(filteredSlides);
+            }
+        }
+    }
 }