Minor: Set completion tracking (#19)

core/include/ccm/services/YuGiOhSetCompletion.hpp

@@ -0,0 +1,60 @@
+#pragma once
+
+// Pure helpers: Yu-Gi-Oh! set-completion progress and per-set checklists.
+// Ownership counts only when collection card.set.id matches the pack and the
+// printing slot matches a catalog setNo (ygoPrintingSlotsMatch). Duplicates /
+// amount / rarity / firstEdition do not inflate the numerator. An optional
+// languageFilter restricts ownership to cards of that language (packs with
+// zero matches are omitted).
+
+#include "ccm/domain/Enums.hpp"
+#include "ccm/domain/YuGiOhCard.hpp"
+#include "ccm/domain/YuGiOhSetCatalog.hpp"
+
+#include <cstddef>
+#include <optional>
+#include <string>
+#include <string_view>
+#include <vector>
+
+namespace ccm {
+
+struct YuGiOhSetCompletionProgress {
+    std::string setId;
+    std::string setName;
+    std::size_t ownedUnique{0};
+    std::size_t total{0};
+
+    [[nodiscard]] int percent() const noexcept {
+        if (total == 0) return 0;
+        return static_cast<int>((ownedUnique * 100) / total);
+    }
+};
+
+struct YuGiOhChecklistEntry {
+    std::string setNo;
+    std::string name;
+    bool        owned{false};
+};
+
+// Distinct languages present in the collection, in allLanguages() order.
+[[nodiscard]] std::vector<Language>
+yuGiOhLanguagesInCollection(const std::vector<YuGiOhCard>& collection);
+
+// Packs where the collection owns ≥1 card with matching set.id, ordered by
+// setName. Packs absent from the catalog are skipped. When languageFilter is
+// set, only cards of that language count toward ownership.
+[[nodiscard]] std::vector<YuGiOhSetCompletionProgress>
+computeYuGiOhSetCompletion(const std::vector<YuGiOhCard>& collection,
+                           const YuGiOhSetCatalog&         catalog,
+                           std::optional<Language> languageFilter = std::nullopt);
+
+// Full catalog checklist for one pack; owned flags from the collection.
+// When languageFilter is set, only cards of that language count as owned.
+[[nodiscard]] std::vector<YuGiOhChecklistEntry>
+yuGiOhChecklistForSet(const std::vector<YuGiOhCard>& collection,
+                      const YuGiOhSetCatalog&         catalog,
+                      std::string_view                setId,
+                      std::optional<Language> languageFilter = std::nullopt);
+
+}  // namespace ccm