[Card] Add a Tag attribute to the card filter tree

libcockatrice_filters/libcockatrice/filters/filter_card.cpp

@@ -84,6 +84,8 @@ const QString CardFilter::attrName(Attr a)
             return tr("Loyalty");
         case AttrFormat:
             return tr("Format");
+        case AttrTag:
+            return tr("Tag");
         case AttrMainType:
             return tr("Main Type");
         case AttrSubType:

libcockatrice_filters/libcockatrice/filters/filter_card.h

@@ -43,6 +43,7 @@ public:
         AttrMainType,
         AttrSubType,
         AttrFormat,
+        AttrTag,
         AttrEnd,
     };
 

libcockatrice_filters/libcockatrice/filters/filter_tree.cpp

@@ -3,6 +3,7 @@
 #include "filter_card.h"
 
 #include <QList>
+#include <libcockatrice/card/game_specific_terms.h>
 
 template <class T> FilterTreeNode *FilterTreeBranch<T>::nodeAt(int i) const
 {
@@ -341,6 +342,16 @@ bool FilterItem::acceptFormat(const CardInfoPtr info) const
     return info->getLegalityProp(term.toLower()) == "legal";
 }
 
+bool FilterItem::acceptTag(const CardInfoPtr info) const
+{
+    const QString stored = info->getProperty(Mtg::Tags);
+    if (stored.isEmpty()) {
+        return false;
+    }
+    // Tags are stored space-separated; match whole slugs, not substrings.
+    return stored.split(" ", Qt::SkipEmptyParts).contains(term.trimmed(), Qt::CaseInsensitive);
+}
+
 bool FilterItem::acceptLoyalty(const CardInfoPtr info) const
 {
     if (info->getLoyalty().isEmpty()) {
@@ -495,6 +506,8 @@ bool FilterItem::acceptCardAttr(const CardInfoPtr info,
             return acceptLoyalty(info);
         case CardFilter::AttrFormat:
             return acceptFormat(info);
+        case CardFilter::AttrTag:
+            return acceptTag(info);
         case CardFilter::AttrMainType:
             return acceptMainType(info);
         case CardFilter::AttrSubType:

libcockatrice_filters/libcockatrice/filters/filter_tree.h

@@ -228,6 +228,7 @@ public:
     [[nodiscard]] bool
     acceptCardAttr(CardInfoPtr info, CardFilter::Attr attr, const CardSearchLanguage &searchLanguage) const;
     [[nodiscard]] bool acceptFormat(CardInfoPtr info) const;
+    [[nodiscard]] bool acceptTag(CardInfoPtr info) const;
     [[nodiscard]] bool relationCheck(int cardInfo) const;
 };
 

tests/carddatabase/filter_string_test.cpp

@@ -3,6 +3,7 @@
 
 #include "gtest/gtest.h"
 #include <libcockatrice/filters/filter_string.h>
+#include <libcockatrice/filters/filter_tree.h>
 #include <libcockatrice/interfaces/noop_card_preference_provider.h>
 #include <libcockatrice/interfaces/noop_card_set_priority_controller.h>
 
@@ -160,6 +161,23 @@ TEST_F(CardQuery, TagQueryTreatsCommasAsPartOfTheSlug)
     ASSERT_FALSE(FilterString("tags:ramp,removal").check(tagged));
 }
 
+TEST_F(CardQuery, FilterTreeTagAttribute)
+{
+    const CardData tagged = taggedCard();
+
+    FilterTree matching;
+    matching.termNode(CardFilter::AttrTag, CardFilter::TypeAnd, "ramp");
+    ASSERT_TRUE(matching.acceptsCard(tagged, CardSearchLanguage{}));
+
+    FilterTree partial;
+    partial.termNode(CardFilter::AttrTag, CardFilter::TypeAnd, "ram");
+    ASSERT_FALSE(partial.acceptsCard(tagged, CardSearchLanguage{}));
+
+    FilterTree missing;
+    missing.termNode(CardFilter::AttrTag, CardFilter::TypeAnd, "squirrel");
+    ASSERT_FALSE(missing.acceptsCard(tagged, CardSearchLanguage{}));
+}
+
 TEST_F(CardQuery, TagQueryFalseWhenCardHasNoTags)
 {
     ASSERT_FALSE(FilterString("tags:ramp").check(cat));