Fixed date and time consistency across Campaigns and Missions

This fixes campaign mission generation mostly, but a full playthrough
will be needed. Missions now serialize and accept stardate setting a
bit better. Thanks to this, date is propagated over multiplayer, too.

This seems to break points system?

Code-wise, this does not workaround the problems from before namely
over-reliance on side-effects. Stardate class is at least one small
step into good direction. Now, it'd be nice to attach clocks to
simulation and campaign and whatever else that needs them.

1 files changed, 137 insertions, 0 deletions

diff --git a/StarsEx/Stardate.cpp b/StarsEx/Stardate.cpp
new file mode 100644
index 0000000..f57205a
--- /dev/null
+++ b/StarsEx/Stardate.cpp
@@ -0,0 +1,137 @@
+/*  Starshatter: The Open Source Project
+    Copyright (c) 2021-2024, Starshatter: The Open Source Project Contributors
+    Copyright (c) 2011-2012, Starshatter OpenSource Distribution Contributors
+    Copyright (c) 1997-2006, Destroyer Studios LLC.
+*/
+
+#include "Stardate.h"
+
+#include <cstdint>
+
+#include <Text.h>
+
+#include "Clock.h"
+
+
+namespace starshatter
+{
+namespace engine
+{
+
+
+static constexpr long double EPOCH {0.5e9l};
+static constexpr long double MINUTE {60};
+static constexpr long double HOUR {60 * MINUTE};
+static constexpr long double DAY {24 * HOUR};
+static long double operation_start {};
+static long double mission_start {};
+
+
+Stardate::Stardate() :
+	value {0}
+{
+}
+
+
+Stardate::Stardate(long double value_) :
+	value {value_}
+{
+}
+
+
+Stardate::operator long double() const
+{
+	return value;
+}
+
+
+Text
+Stardate::Format(bool short_format) const
+{
+	auto time = value;
+	std::int_fast32_t day = 1, hours = 0, minutes = 0, seconds = 0;
+	while (time >= DAY) {
+		time -= DAY;
+		++day;
+	}
+	while (time >= HOUR) {
+		time -= HOUR;
+		++hours;
+	}
+	while (time >= MINUTE) {
+		time -= MINUTE;
+		++minutes;
+	}
+	seconds = time;
+	return Text::format(
+		short_format ? "%02d/%02d:%02d:%02d" : "Day %d, %02d:%02d:%02d",
+		day, hours, minutes, seconds);
+}
+
+
+Stardate
+CurrentTime()
+{
+	return Epoch() + OperationStart() + OperationTime();
+}
+
+
+Stardate
+OperationTime()
+{
+	return MissionStart() + MissionTime();
+}
+
+
+Stardate
+MissionTime()
+{
+	if (const auto* clock = Clock::GetInstance())
+		return clock->GameTime<long double>() / 1000.0l;
+	throw "game clock not initialized";
+}
+
+
+long double
+Epoch()
+{
+	return EPOCH;
+}
+
+
+long double
+OperationStart()
+{
+	return operation_start;
+}
+
+
+long double
+MissionStart()
+{
+	return mission_start;
+}
+
+
+void
+SetOperationStart(long double value, bool relative)
+{
+	if (relative)
+		operation_start += value;
+	else
+		operation_start = value;
+}
+
+
+void
+SetMissionStart(long double value, bool relative)
+{
+	if (relative)
+		mission_start += value;
+	else
+		mission_start = value;
+}
+
+
+}  // namespace engine
+}  // namespace starshatter