package net.pterodactylus.sone.notify;
-import static com.google.common.base.Preconditions.checkNotNull;
-
+import java.util.function.Predicate;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;
-import javax.inject.Singleton;
import net.pterodactylus.sone.data.Post;
import net.pterodactylus.sone.data.Sone;
-import net.pterodactylus.sone.freenet.wot.OwnIdentity;
-import net.pterodactylus.sone.freenet.wot.Trust;
-import net.pterodactylus.util.notify.Notification;
-import com.google.common.base.Predicate;
+import com.google.inject.ImplementedBy;
-/**
- * Filters {@link Notification}s involving {@link Post}s.
- *
- * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
- */
-@Singleton
-public class PostVisibilityFilter {
+@ImplementedBy(DefaultPostVisibilityFilter.class)
+public interface PostVisibilityFilter {
- /**
- * Checks whether a post is visible to the given Sone. A post is not
- * considered visible if one of the following statements is true:
- * <ul>
- * <li>The post does not have a Sone.</li>
- * <li>The post’s {@link Post#getTime() time} is in the future.</li>
- * </ul>
- * <p>
- * If {@code post} is not {@code null} more checks are performed, and the
- * post will be invisible if:
- * </p>
- * <ul>
- * <li>The Sone of the post is not the given Sone, the given Sone does not
- * follow the post’s Sone, and the given Sone is not the recipient of the
- * post.</li>
- * <li>The trust relationship between the two Sones can not be retrieved.</li>
- * <li>The given Sone has explicitely assigned negative trust to the post’s
- * Sone.</li>
- * <li>The given Sone has not explicitely assigned negative trust to the
- * post’s Sone but the implicit trust is negative.</li>
- * </ul>
- * If none of these statements is true the post is considered visible.
- *
- * @param sone
- * The Sone that checks for a post’s visibility (may be
- * {@code null} to skip Sone-specific checks, such as trust)
- * @param post
- * The post to check for visibility
- * @return {@code true} if the post is considered visible, {@code false}
- * otherwise
- */
- boolean isPostVisible(@Nullable Sone sone, @Nonnull Post post) {
- checkNotNull(post, "post must not be null");
- if (!post.isLoaded()) {
- return false;
- }
- Sone postSone = post.getSone();
- if (sone != null) {
- Trust trust = postSone.getIdentity().getTrust((OwnIdentity) sone.getIdentity());
- if (trust != null) {
- if ((trust.getExplicit() != null) && (trust.getExplicit() < 0)) {
- return false;
- }
- if ((trust.getExplicit() == null) && (trust.getImplicit() != null) && (trust.getImplicit() < 0)) {
- return false;
- }
- } else {
- /*
- * a null trust means that the trust updater has not yet
- * received a trust value for this relation. if we return false,
- * the post feed will stay empty until the trust updater has
- * received trust values. to prevent this we simply assume that
- * posts are visible if there is no trust.
- */
- }
- if ((!postSone.equals(sone)) && !sone.hasFriend(postSone.getId()) && !sone.getId().equals(post.getRecipientId().orNull())) {
- return false;
- }
- }
- return post.getTime() <= System.currentTimeMillis();
- }
+ boolean isPostVisible(@Nullable Sone sone, @Nonnull Post post);
@Nonnull
- public Predicate<Post> isVisible(@Nullable final Sone currentSone) {
- return new Predicate<Post>() {
- @Nonnull
- @Override
- public boolean apply(@Nullable Post post) {
- return isPostVisible(currentSone, post);
- }
- };
- }
+ Predicate<Post> isVisible(@Nullable Sone currentSone);
}