1 files changed, 94 insertions, 0 deletions
diff --git a/src/util/format.hpp b/src/util/format.hpp
new file mode 100644
index 00000000..874c5b43
--- /dev/null
+++ b/src/util/format.hpp
@@ -0,0 +1,94 @@
+#pragma once
+#include "pre.hpp"
+
+#include "base.hpp"
+
+namespace cru::util {
+namespace details {
+constexpr StringView PlaceHolder(type_tag<String>) { return StringView(L"{}"); }
+
+constexpr MultiByteStringView PlaceHolder(type_tag<MultiByteString>) {
+  return MultiByteStringView("{}");
+}
+
+template <typename TString>
+void FormatInternal(TString& string) {
+  const auto find_result = string.find(PlaceHolder(type_tag<TString>{}));
+  if (find_result != TString::npos)
+    throw std::invalid_argument("There is more placeholders than args.");
+}
+
+template <typename TString, typename T, typename... TRest>
+void FormatInternal(TString& string, const T& arg, const TRest&... args) {
+  const auto find_result = string.find(PlaceHolder(type_tag<TString>{}));
+  if (find_result == TString::npos)
+    throw std::invalid_argument("There is less placeholders than args.");
+
+  string.replace(find_result, 2, FormatToString(arg, type_tag<TString>{}));
+  FormatInternal<TString>(string, args...);
+}
+}  // namespace details
+
+template <typename... T>
+String Format(const StringView& format, const T&... args) {
+  String result(format);
+  details::FormatInternal<String>(result, args...);
+  return result;
+}
+
+template <typename... T>
+MultiByteString Format(const MultiByteStringView& format, const T&... args) {
+  MultiByteString result(format);
+  details::FormatInternal<MultiByteString>(result, args...);
+  return result;
+}
+
+#define CRU_FORMAT_NUMBER(type)                                       \
+  inline String FormatToString(const type number, type_tag<String>) { \
+    return std::to_wstring(number);                                   \
+  }                                                                   \
+  inline MultiByteString FormatToString(const type number,            \
+                                        type_tag<MultiByteString>) {  \
+    return std::to_string(number);                                    \
+  }
+
+CRU_FORMAT_NUMBER(int)
+CRU_FORMAT_NUMBER(short)
+CRU_FORMAT_NUMBER(long)
+CRU_FORMAT_NUMBER(long long)
+CRU_FORMAT_NUMBER(unsigned int)
+CRU_FORMAT_NUMBER(unsigned short)
+CRU_FORMAT_NUMBER(unsigned long)
+CRU_FORMAT_NUMBER(unsigned long long)
+CRU_FORMAT_NUMBER(float)
+CRU_FORMAT_NUMBER(double)
+
+#undef CRU_FORMAT_NUMBER
+
+inline StringView FormatToString(const String& string, type_tag<String>) {
+  return string;
+}
+
+inline MultiByteString FormatToString(const MultiByteString& string,
+                                      type_tag<MultiByteString>) {
+  return string;
+}
+
+inline StringView FormatToString(const StringView& string, type_tag<String>) {
+  return string;
+}
+
+inline MultiByteStringView FormatToString(const MultiByteStringView& string,
+                                          type_tag<MultiByteString>) {
+  return string;
+}
+
+inline StringView FormatToString(const wchar_t* string, type_tag<String>) {
+  return StringView(string);
+}
+
+inline MultiByteStringView FormatToString(const char* string,
+                                          type_tag<MultiByteString>) {
+  return MultiByteString(string);
+}
+}  // namespace cru::util