[libdanbooru/utils] Add a convenience function to check if a post is

unwanted

This is mainly done to reduce the complexity of the post handing in
DanbooruService.

src/libdanbooru/utils.cpp

@@ -174,4 +174,21 @@ namespace Danbooru {
     }
 
 
+bool isPostBlacklisted(DanbooruPost *post, QSet<QString> blacklist, DanbooruPost::Ratings maxRating ) {
+
+    if (post->rating() > maxRating) {
+        return true;
+    }
+
+    for (auto tag: post->tags()) {
+
+        if (blacklist.contains(tag)) {
+             return true;
+        }
+    }
+
+    return false;
+
+}
+
 } // namespace Danbooru

src/libdanbooru/utils.h

@@ -23,6 +23,8 @@
 #ifndef UTILS_H
 #define UTILS_H
 
+#include "danboorupost.h"
+
 // Qt
 
 #include <QtCore/QStringList>
@@ -108,6 +110,19 @@ namespace Danbooru {
                                         bool* result);
     QVariant parseDanbooruResult(QByteArray data, bool* result);
 
+    /**
+     * @brief Check if a post can be allowed.
+     *
+     * This convenience function checks if a DanbooruPost is not allowed, either because it
+     * contains blacklisted tags, or because it has a higher rating than allowed.
+     *
+     * @param post A DanbooruPost pointer.
+     * @param blacklist A QSet containing unwanted tag names as QStrings.
+     * @param maxRating The maximum allowed rating expressed as a DanbooruPost::Ratings flag.
+     * @return true if the post is unwanted, false otherwise.
+     * @author Luca Beltrame (lbeltrame@kde.org)
+     */
+    bool isPostBlacklisted(DanbooruPost *post, QSet<QString> blacklist, DanbooruPost::Ratings maxRating );
 
 }
 #endif // UTILS_H