Add skeleton CountryRelationManager

Change `DiplomaticAction::Argument` to refer to `CountryInstance*` instead of `Country*`
Add `GameManager&` argument to `DiplomaticActionManager::setup_diplomatic_actions`
Add some ErrorMacros, likely and unlikely macros and stringization macros (based on Godot's macros)
Implement `increase_relations` DiplomaticAction commit function
Implement `decrease_relations` DiplomaticAction commit function
Fix include StringUtils.hpp errors

3 files changed, 121 insertions, 11 deletions

diff --git a/src/openvic-simulation/utility/ErrorMacros.hpp b/src/openvic-simulation/utility/ErrorMacros.hpp
new file mode 100644
index 0000000..47b73d5
--- /dev/null
+++ b/src/openvic-simulation/utility/ErrorMacros.hpp
@@ -0,0 +1,68 @@
+#pragma once
+
+#include "openvic-simulation/utility/Logger.hpp" // IWYU pragma: keep
+#include "openvic-simulation/utility/Utility.hpp"
+
+/**
+ * Try using `ERR_FAIL_COND_MSG`.
+ * Only use this macro if there is no sensible error message.
+ * If checking for null use ERR_FAIL_NULL_MSG instead.
+ * If checking index bounds use ERR_FAIL_INDEX_MSG instead.
+ *
+ * Ensures `m_cond` is false.
+ * If `m_cond` is true, the current function returns.
+ */
+#define OV_ERR_FAIL_COND(m_cond) \
+	if (OV_unlikely(m_cond)) { \
+		::OpenVic::Logger::error("Condition \"" _OV_STR(m_cond) "\" is true."); \
+		return; \
+	} else \
+		((void)0)
+
+/**
+ * Ensures `m_cond` is false.
+ * If `m_cond` is true, prints `m_msg` and the current function returns.
+ *
+ * If checking for null use ERR_FAIL_NULL_MSG instead.
+ * If checking index bounds use ERR_FAIL_INDEX_MSG instead.
+ */
+#define OV_ERR_FAIL_COND_MSG(m_cond, m_msg) \
+	if (OV_unlikely(m_cond)) { \
+		::OpenVic::Logger::error("Condition \"" _OV_STR(m_cond) "\" is true.", m_msg); \
+		return; \
+	} else \
+		((void)0)
+
+/**
+ * Try using `ERR_FAIL_COND_V_MSG`.
+ * Only use this macro if there is no sensible error message.
+ * If checking for null use ERR_FAIL_NULL_V_MSG instead.
+ * If checking index bounds use ERR_FAIL_INDEX_V_MSG instead.
+ *
+ * Ensures `m_cond` is false.
+ * If `m_cond` is true, the current function returns `m_retval`.
+ */
+#define OV_ERR_FAIL_COND_V(m_cond, m_retval) \
+	if (OV_unlikely(m_cond)) { \
+		::OpenVic::Logger::error( \
+			"Condition \"" _OV_STR(m_cond) "\" is true. Returning: " _OV_STR(m_retval) \
+		); \
+		return m_retval; \
+	} else \
+		((void)0)
+
+/**
+ * Ensures `m_cond` is false.
+ * If `m_cond` is true, prints `m_msg` and the current function returns `m_retval`.
+ *
+ * If checking for null use ERR_FAIL_NULL_V_MSG instead.
+ * If checking index bounds use ERR_FAIL_INDEX_V_MSG instead.
+ */
+#define OV_ERR_FAIL_COND_V_MSG(m_cond, m_retval, m_msg) \
+	if (OV_unlikely(m_cond)) { \
+		::OpenVic::Logger::error( \
+			"Condition \"" _OV_STR(m_cond) "\" is true. Returning: " _OV_STR(m_retval), m_msg \
+		); \
+		return m_retval; \
+	} else \
+		((void)0)
diff --git a/src/openvic-simulation/utility/StringUtils.hpp b/src/openvic-simulation/utility/StringUtils.hpp
index c5a0b71..1be818a 100644
--- a/src/openvic-simulation/utility/StringUtils.hpp
+++ b/src/openvic-simulation/utility/StringUtils.hpp
@@ -1,9 +1,11 @@
 #pragma once
 
+#include <algorithm>
 #include <cctype>
 #include <cstdint>
 #include <cstring>
 #include <limits>
+#include <string>
 #include <string_view>
 
 namespace OpenVic::StringUtils {
diff --git a/src/openvic-simulation/utility/Utility.hpp b/src/openvic-simulation/utility/Utility.hpp
index 0387e7f..dbbcf8f 100644
--- a/src/openvic-simulation/utility/Utility.hpp
+++ b/src/openvic-simulation/utility/Utility.hpp
@@ -4,6 +4,21 @@
 #include <functional>
 #include <type_traits>
 
+#if defined(__GNUC__)
+#define OV_likely(x) __builtin_expect(!!(x), 1)
+#define OV_unlikely(x) __builtin_expect(!!(x), 0)
+#else
+#define OV_likely(x) x
+#define OV_unlikely(x) x
+#endif
+
+// Turn argument to string constant:
+// https://gcc.gnu.org/onlinedocs/cpp/Stringizing.html#Stringizing
+#ifndef _OV_STR
+#define _OV_STR(m_x) #m_x
+#define _OV_MKSTR(m_x) _OV_STR(m_x)
+#endif
+
 namespace OpenVic::utility {
 	[[noreturn]] inline void unreachable() {
 		// Uses compiler specific extensions if possible.
@@ -25,29 +40,35 @@ namespace OpenVic::utility {
 	template<size_t Shift, class T>
 	constexpr inline void hash_combine_index(std::size_t& s, const T& v) {
 		std::hash<T> h;
-		if constexpr(Shift == 0) {
+		if constexpr (Shift == 0) {
 			s = h(v);
 		} else {
 			s ^= h(v) << Shift;
 		}
 	}
 
-	template<class T, typename ...Args>
+	template<class T, typename... Args>
 	constexpr void perfect_hash(std::size_t& s, T&& v, Args&&... args) {
-		static_assert(sizeof(T) + (sizeof(Args) + ...) <= sizeof(std::size_t), "Perfect hashes must be able to fit into size_t");
+		static_assert(
+			sizeof(T) + (sizeof(Args) + ...) <= sizeof(std::size_t), "Perfect hashes must be able to fit into size_t"
+		);
 		std::hash<T> h;
-		if constexpr(sizeof...(args) == 0) {
+		if constexpr (sizeof...(args) == 0) {
 			s = h(v);
 		} else {
 			const std::tuple arg_tuple { args... };
 			s = h(v) << (sizeof(T) * CHAR_BIT);
-			([&]{
-				// If args is not last pointer of args
-				if (static_cast<const void*>(&(std::get<sizeof...(args) - 1>(arg_tuple))) != static_cast<const void*>(&args)) {
-					s <<= sizeof(Args) * CHAR_BIT;
-				}
-				s |= std::hash<Args>{}(args);
-			}(), ...);
+			(
+				[&] {
+					// If args is not last pointer of args
+					if (static_cast<const void*>(&(std::get<sizeof...(args) - 1>(arg_tuple))) !=
+						static_cast<const void*>(&args)) {
+						s <<= sizeof(Args) * CHAR_BIT;
+					}
+					s |= std::hash<Args> {}(args);
+				}(),
+				...
+			);
 		}
 	}
 
@@ -59,4 +80,23 @@ namespace OpenVic::utility {
 
 	template<typename T, template<typename...> class Z>
 	inline constexpr bool is_specialization_of_v = is_specialization_of<T, Z>::value;
+
+	inline constexpr auto three_way(auto&& left, auto&& right) {
+		// This is Apple's fault again
+		#if __cpp_lib_three_way_comparison >= 201907L
+		if constexpr (std::three_way_comparable_with<std::decay_t<decltype(left)>, std::decay_t<decltype(right)>>) {
+			return left <=> right;
+		} else
+		#endif
+		{
+			if (left < right) {
+				return std::weak_ordering::less;
+			} else if (left > right) {
+				return std::weak_ordering::greater;
+			} else {
+				return std::weak_ordering::equivalent;
+			}
+		}
+	};
+
 }