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mcc/mcc_generics.h

@@ -150,6 +150,55 @@ concept mcc_julday_c = mcc_fp_type_like_c<T> && requires(const T v) {
 };
 
 
+/*                          CELESTIAL COORDINATES EPOCH CLASS CONCEPT                           */
+
+struct mcc_coord_epoch_interface_t {
+    static constexpr double MJD0 = 2400000.5;
+
+    template <std::derived_from<mcc_coord_epoch_interface_t> SelfT, traits::mcc_input_char_range IR>
+    bool fromCharRange(this SelfT&& self, IR&& str)
+    {
+        return std::forward<decltype(self)>(self).fromCharRange(std::forward<IR>(str));
+    }
+
+    template <std::derived_from<mcc_coord_epoch_interface_t> SelfT, typename ClockT, typename DurT>
+    bool fromTimePoint(this SelfT&& self, std::chrono::time_point<ClockT, DurT>&& tp)
+    {
+        return std::forward<decltype(self)>(self).fromTimePoint(std::forward<decltype(tp)>(tp));
+    }
+
+    template <std::derived_from<mcc_coord_epoch_interface_t> SelfT, typename VT>
+    bool fromMJD(this SelfT&& self, VT&& mjd)
+        requires std::is_arithmetic_v<VT>
+    {
+        return std::forward<decltype(self)>(self).fromMJD(std::forward<VT>(mjd));
+    }
+
+    template <std::derived_from<mcc_coord_epoch_interface_t> SelfT, traits::mcc_time_duration_c DT>
+    SelfT& operator+=(this SelfT& self, DT&& dt)
+    {
+        return std::forward<decltype(self)>(self).operator+=(std::forward<DT>(dt));
+    }
+
+    template <std::derived_from<mcc_coord_epoch_interface_t> SelfT, traits::mcc_time_duration_c DT>
+    SelfT& operator-=(this SelfT& self, DT&& dt)
+    {
+        return std::forward<decltype(self)>(self).operator-=(std::forward<DT>(dt));
+    }
+};
+
+template <typename T>
+concept mcc_coord_epoch_c = std::derived_from<T, mcc_coord_epoch_interface_t> && requires(T t1, T t2, const T t_const) {
+    { t_const.MJD() } -> std::convertible_to<double>;
+    { t_const.UTC() } -> traits::mcc_systime_c;
+    { t_const.JEpoch() } -> traits::mcc_output_char_range;
+
+    { t1 <=> t2 };
+
+    { T::now() } -> std::same_as<T>;
+};
+
+
 /*                          ERROR CLASS CONCEPT                            */
 
 template <typename T>