kstd: clean up units

2 files changed, 135 insertions, 92 deletions

diff --git a/libs/kstd/kstd/bits/basic_unit.hpp b/libs/kstd/kstd/bits/basic_unit.hpp
new file mode 100644
index 00000000..c7f794ea
--- /dev/null
+++ b/libs/kstd/kstd/bits/basic_unit.hpp
@@ -0,0 +1,117 @@
+#ifndef KSTD_BITS_BASIC_UNITS_HPP
+#define KSTD_BITS_BASIC_UNITS_HPP
+
+#include <concepts>
+#include <utility>
+
+namespace kstd
+{
+
+  //! A basic template for strongly typed units.
+  template<typename ValueType, typename Tags>
+  struct basic_unit
+  {
+    using value_type = ValueType;
+
+    constexpr basic_unit() noexcept
+        : value{}
+    {}
+
+    explicit constexpr basic_unit(value_type value) noexcept
+        : value{value}
+    {}
+
+    template<std::integral T>
+    explicit constexpr operator T() const noexcept
+    {
+      return value;
+    }
+
+    constexpr auto friend operator+=(basic_unit & lhs, basic_unit const & rhs) noexcept -> basic_unit &
+    {
+      lhs.value += rhs.value;
+      return lhs;
+    }
+
+    constexpr auto friend operator+(basic_unit lhs, basic_unit const & rhs) noexcept -> basic_unit
+    {
+      return lhs += rhs;
+    }
+
+    constexpr auto friend operator-=(basic_unit & lhs, basic_unit const & rhs) noexcept -> basic_unit &
+    {
+      lhs.value -= rhs.value;
+      return lhs;
+    }
+
+    constexpr auto friend operator-(basic_unit lhs, basic_unit const & rhs) noexcept -> basic_unit
+    {
+      return lhs -= rhs;
+    }
+
+    constexpr auto friend operator*=(basic_unit & lhs, std::integral auto factor) noexcept -> basic_unit &
+    {
+      lhs.value *= factor;
+      return lhs;
+    }
+
+    constexpr auto friend operator*(basic_unit lhs, std::integral auto factor) noexcept -> basic_unit
+    {
+      return lhs *= factor;
+    }
+
+    constexpr auto friend operator*(std::integral auto factor, basic_unit rhs) noexcept -> basic_unit
+    {
+      return rhs *= factor;
+    }
+
+    constexpr auto friend operator/=(basic_unit & lhs, std::integral auto divisor) noexcept -> basic_unit &
+    {
+      lhs.value /= divisor;
+      return lhs;
+    }
+
+    constexpr auto friend operator/(basic_unit lhs, std::integral auto divisor) noexcept -> basic_unit
+    {
+      return lhs /= divisor;
+    }
+
+    constexpr auto friend operator%=(basic_unit & lhs, std::integral auto divisor) noexcept -> basic_unit &
+    {
+      lhs.value %= divisor;
+      return lhs;
+    }
+
+    constexpr auto friend operator%(basic_unit lhs, std::integral auto divisor) noexcept -> basic_unit
+    {
+      return lhs %= divisor;
+    }
+
+    constexpr auto friend operator/(basic_unit const & lhs, basic_unit const & rhs) noexcept
+        -> decltype(std::declval<value_type>() / std::declval<value_type>())
+    {
+      return lhs.value / rhs.value;
+    }
+
+    constexpr auto friend operator%(basic_unit const & lhs, basic_unit const & rhs) noexcept -> basic_unit
+    {
+      return basic_unit{lhs.value % rhs.value};
+    }
+
+    constexpr auto friend operator-(basic_unit const & unit) noexcept -> basic_unit
+      requires(std::is_signed_v<value_type>)
+    {
+      return basic_unit{-unit.value};
+    }
+
+    constexpr auto friend operator<=>(basic_unit const &, basic_unit const &) noexcept
+        -> decltype(std::declval<value_type const &>() <=> std::declval<value_type const &>()) = default;
+
+    constexpr auto friend operator==(basic_unit const &, basic_unit const &) noexcept -> bool = default;
+
+    value_type value;
+  };
+
+}  // namespace kstd
+
+#endif
diff --git a/libs/kstd/kstd/units.hpp b/libs/kstd/kstd/units.hpp
index 6e9ea1e2..cb33af21 100644
--- a/libs/kstd/kstd/units.hpp
+++ b/libs/kstd/kstd/units.hpp
@@ -1,112 +1,35 @@
 #ifndef KSTD_UNITS_HPP
 #define KSTD_UNITS_HPP
 
-#include <compare>
+#include <kstd/bits/basic_unit.hpp>
+
 #include <concepts>
 #include <cstddef>
 
 namespace kstd
 {
 
-  //! A basic template for strongly typed units.
-  template<typename ValueType, typename Tag>
-  struct basic_unit
-  {
-    using value_type = ValueType;
-
-    constexpr basic_unit() noexcept
-        : value{}
-    {}
-
-    explicit constexpr basic_unit(value_type value) noexcept
-        : value{value}
-    {}
-
-    template<std::integral T>
-    explicit constexpr operator T() const noexcept
-    {
-      return value;
-    }
-
-    constexpr auto operator+(basic_unit const & other) const noexcept -> basic_unit
-    {
-      return basic_unit{value + other.value};
-    }
-
-    constexpr auto operator+=(basic_unit const & other) noexcept -> basic_unit &
-    {
-      return *this = *this + other;
-    }
-
-    constexpr auto operator-(basic_unit const & other) const noexcept -> basic_unit
-    {
-      return basic_unit{value - other.value};
-    }
-
-    constexpr auto operator-=(basic_unit const & other) noexcept -> basic_unit &
-    {
-      return *this = *this - other;
-    }
-
-    constexpr auto operator*(std::integral auto factor) const noexcept -> basic_unit
-    {
-      return basic_unit{value * factor};
-    }
-
-    constexpr auto operator*=(std::integral auto factor) noexcept -> basic_unit
-    {
-      return *this = *this * factor;
-    }
-
-    constexpr auto operator/(std::integral auto divisor) const noexcept -> basic_unit
-    {
-      return basic_unit{value / divisor};
-    }
-
-    constexpr auto operator/=(std::integral auto divisor) noexcept -> basic_unit
-    {
-      return *this = *this / divisor;
-    }
-
-    constexpr auto operator/(basic_unit const & other) const noexcept
-    {
-      return value / other.value;
-    }
-
-    constexpr auto operator%(basic_unit const & other) const noexcept -> basic_unit
-    {
-      return basic_unit{value % other.value};
-    }
-
-    constexpr auto operator<=>(basic_unit const & other) const noexcept -> std::strong_ordering = default;
-
-    value_type value;
-  };
-
-  template<std::integral Factor, typename ValueType, typename Tag>
-  constexpr auto operator*(Factor factor, basic_unit<ValueType, Tag> const & unit) noexcept
-      -> basic_unit<ValueType, Tag>
-  {
-    return basic_unit<ValueType, Tag>{unit.value * factor};
-  }
-
   namespace units
   {
+
     using bytes = basic_unit<std::size_t, struct bytes_tag>;
 
-    constexpr auto KiB(std::size_t value) noexcept -> bytes
+    // NOLINTNEXTLINE(readability-identifier-naming)
+    constexpr auto KiB(std::unsigned_integral auto value) noexcept -> bytes
     {
-      return bytes{value * 1024};
+      return bytes{static_cast<bytes::value_type>(value) * 1024};
     }
 
-    constexpr auto MiB(std::size_t value) noexcept -> bytes
+    // NOLINTNEXTLINE(readability-identifier-naming)
+    constexpr auto MiB(std::unsigned_integral auto value) noexcept -> bytes
     {
-      return bytes{value * 1024 * 1024};
+      return bytes{static_cast<bytes::value_type>(value) * 1024 * 1024};
     }
 
-    constexpr auto GiB(std::size_t value) noexcept -> bytes
+    // NOLINTNEXTLINE(readability-identifier-naming)
+    constexpr auto GiB(std::unsigned_integral auto value) noexcept -> bytes
     {
-      return bytes{value * 1024 * 1024 * 1024};
+      return bytes{static_cast<bytes::value_type>(value) * 1024 * 1024 * 1024};
     }
 
     template<typename ValueType>
@@ -142,13 +65,16 @@ namespace kstd
   }  // namespace units_literals
 
   template<typename ValueType>
-  constexpr auto object_size(ValueType const &) -> units::bytes
+  consteval auto size_of(ValueType const &) noexcept -> units::bytes
   {
     return units::bytes{sizeof(ValueType)};
   }
 
-  template<typename T>
-  constexpr auto type_size = units::bytes{sizeof(T)};
+  template<typename ValueType>
+  consteval auto size_of() noexcept -> units::bytes
+  {
+    return units::bytes{sizeof(ValueType)};
+  }
 
 }  // namespace kstd