time wip

It works now, but some functionality is lost in main/draw.cpp

1 files changed, 76 insertions, 0 deletions

diff --git a/src/timer.cpp b/src/timer.cpp
new file mode 100644
index 00000000..0b87ac06
--- /dev/null
+++ b/src/timer.cpp
@@ -0,0 +1,76 @@
+#include "timer.hpp"
+#include "compat/assert.hpp"
+#include <ctime>
+#include <cstdio>
+#include <chrono>
+#include <mg/Time.h>
+
+namespace floormat {
+
+using std::chrono::duration_cast;
+using std::chrono::duration;
+
+using Clock = std::chrono::high_resolution_clock;
+using SystemClock = std::chrono::system_clock;
+using Nsecs = duration<uint64_t, std::nano>;
+using Millis = duration<unsigned, std::milli>;
+
+namespace {
+
+template<typename T> struct array_size_;
+template<typename T, size_t N> struct array_size_<T(&)[N]> : std::integral_constant<size_t, N> {};
+template<typename T, size_t N> struct array_size_<std::array<T, N>> : std::integral_constant<size_t, N> {};
+template<typename T> constexpr inline auto array_size = array_size_<T>::value;
+
+uint64_t get_time() noexcept { return duration_cast<Nsecs>(Clock::now().time_since_epoch()).count(); }
+
+const uint64_t Epoch = get_time();
+
+} // namespace
+
+Time Time::now() noexcept
+{
+    auto val = get_time();
+    auto ret = val - Epoch;
+    return {ret};
+}
+
+Ns operator-(const Time& a, const Time& b) noexcept
+{
+    fm_assert(a.stamp >= b.stamp);
+    auto ret = a.stamp - b.stamp;
+    fm_assert(ret < uint64_t{1} << 63);
+    return Ns{ int64_t(ret) };
+}
+
+Ns Time::update(const Time& ts) & noexcept
+{
+    auto ret = ts - *this;
+    stamp = ts.stamp;
+    return ret;
+}
+
+uint64_t Time::init() noexcept { return get_time(); }
+bool Time::operator==(const Time&) const noexcept = default;
+std::strong_ordering Time::operator<=>(const Time&) const noexcept = default;
+
+float Time::to_seconds(const Ns& ts) noexcept { return float(Ns::Type{ts} * 1e-9L); }
+float Time::to_milliseconds(const Ns& ts) noexcept { return float(Ns::Type{ts} * 1e-6L); }
+
+const char* format_datetime_to_string(char (&buf)[fm_DATETIME_BUF_SIZE])
+{
+    constexpr const char* fmt = "%a, %d %b %Y %H:%M:%S.";
+    constexpr size_t fmtsize = std::size("Thu 01 Mon 197000 00:00:00.");
+    static_assert(array_size<decltype(buf)> - fmtsize == 4);
+    const auto t    = SystemClock::now();
+    const auto ms   = duration_cast<Millis>(t.time_since_epoch()) % 1000;
+    const auto time = SystemClock::to_time_t(t);
+    const auto* tm  = std::localtime(&time);
+    auto len = std::strftime(buf, std::size(buf), fmt, tm);
+    fm_assert(len > 0 && len <= fmtsize);
+    auto len2 = std::sprintf(buf + len, "%03u", unsigned{ms.count()});
+    fm_assert(len2 > 0 && len + (size_t)len2 < std::size(buf));
+    return buf;
+}
+
+} // namespace floormat