1 files changed, 58 insertions, 0 deletions
diff --git a/src/openvic-simulation/modifier/ModifierSum.cpp b/src/openvic-simulation/modifier/ModifierSum.cpp
new file mode 100644
index 0000000..8e5ce48
--- /dev/null
+++ b/src/openvic-simulation/modifier/ModifierSum.cpp
@@ -0,0 +1,58 @@
+#include "ModifierSum.hpp"
+
+using namespace OpenVic;
+
+void ModifierSum::clear() {
+	modifiers.clear();
+	value_sum.clear();
+}
+
+bool ModifierSum::empty() {
+	return modifiers.empty();
+}
+
+fixed_point_t ModifierSum::get_effect(ModifierEffect const& effect, bool* effect_found) const {
+	return value_sum.get_effect(effect, effect_found);
+}
+
+bool ModifierSum::has_effect(ModifierEffect const& effect) const {
+	return value_sum.has_effect(effect);
+}
+
+void ModifierSum::add_modifier(Modifier const& modifier, fixed_point_t multiplier) {
+	modifiers[&modifier] += multiplier;
+	value_sum.multiply_add(modifier, multiplier);
+}
+
+void ModifierSum::add_modifier_sum(ModifierSum const& modifier_sum) {
+	modifiers += modifier_sum.modifiers;
+	value_sum += modifier_sum.value_sum;
+}
+
+ModifierSum& ModifierSum::operator+=(Modifier const& modifier) {
+	add_modifier(modifier);
+	return *this;
+}
+
+ModifierSum& ModifierSum::operator+=(ModifierSum const& modifier_sum) {
+	add_modifier_sum(modifier_sum);
+	return *this;
+}
+
+// TODO - include value_sum[effect] in result? Early return if lookup in value_sum fails?
+std::vector<std::pair<Modifier const*, fixed_point_t>> ModifierSum::get_contributing_modifiers(
+	ModifierEffect const& effect
+) const {
+	std::vector<std::pair<Modifier const*, fixed_point_t>> ret;
+
+	for (auto const& [modifier, multiplier] : modifiers) {
+		bool effect_found = false;
+		const fixed_point_t value = modifier->get_effect(effect, &effect_found);
+
+		if (effect_found) {
+			ret.emplace_back(modifier, value * multiplier);
+		}
+	}
+
+	return ret;
+}