Improve the consistency of duration strings.

Unfortunately because of leap years we can't really make duration
strings exact. Because of this we have always added 6 hours on to
each year to make it correct over time.

However, we did not do this in any kind of consistent way which
resulted in weird roundtripped duration strings which made this
very confusing for users

While I'm touching the duration code I've also cleaned it up.

1 files changed, 46 insertions, 17 deletions

diff --git a/src/helperfuncs.cpp b/src/helperfuncs.cpp
index b9ddd2767..e14f0e442 100644
--- a/src/helperfuncs.cpp
+++ b/src/helperfuncs.cpp
@@ -363,6 +363,21 @@ bool InspIRCd::IsSID(const std::string_view& str)
 			((str[2] >= 'A' && str[2] <= 'Z') || isdigit(str[2])));
 }
 
+namespace
+{
+	constexpr const auto SECONDS_PER_MINUTE = 60;
+
+	constexpr const auto SECONDS_PER_HOUR = SECONDS_PER_MINUTE * 60;
+
+	constexpr const auto SECONDS_PER_DAY = SECONDS_PER_HOUR * 24;
+
+	constexpr const auto SECONDS_PER_WEEK = SECONDS_PER_DAY * 7;
+
+	constexpr const auto SECONDS_PER_YEAR = (SECONDS_PER_DAY * 365);
+
+	constexpr const auto SECONDS_PER_AVG_YEAR = SECONDS_PER_YEAR + (SECONDS_PER_HOUR * 6);
+}
+
 /** A lookup table of values for multiplier characters used by
  * Duration::{Try,}From(). In this lookup table, the indexes for
  * the ascii values 'm' and 'M' have the value '60', the indexes
@@ -374,10 +389,10 @@ static constexpr unsigned int duration_multi[] =
 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-	0, 0, 0, 0, 86400, 0, 0, 0, 3600, 0, 0, 0, 0, 60, 0, 0,
-	0, 0, 0, 1, 0, 0, 0, 604800, 0, 31557600, 0, 0, 0, 0, 0, 0,
-	0, 0, 0, 0, 86400, 0, 0, 0, 3600, 0, 0, 0, 0, 60, 0, 0,
-	0, 0, 0, 1, 0, 0, 0, 604800, 0, 31557600, 0, 0, 0, 0, 0, 0,
+	0, 0, 0, 0, SECONDS_PER_DAY, 0, 0, 0, SECONDS_PER_HOUR, 0, 0, 0, 0, SECONDS_PER_MINUTE, 0, 0,
+	0, 0, 0, 1, 0, 0, 0, SECONDS_PER_WEEK, 0, SECONDS_PER_AVG_YEAR, 0, 0, 0, 0, 0, 0,
+	0, 0, 0, 0, SECONDS_PER_DAY, 0, 0, 0, SECONDS_PER_HOUR, 0, 0, 0, 0, SECONDS_PER_MINUTE, 0, 0,
+	0, 0, 0, 1,	0, 0, 0, SECONDS_PER_WEEK, 0, SECONDS_PER_AVG_YEAR, 0, 0, 0, 0, 0, 0,
 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
@@ -449,29 +464,43 @@ std::string Duration::ToString(unsigned long duration)
 
 	std::string ret;
 
-	unsigned long years = duration / 31449600;
+	const auto years = (duration / SECONDS_PER_YEAR);
 	if (years)
-		ret += ConvToStr(years) + "y";
+	{
+		ret = INSP_FORMAT("{}y", years);
+		duration -= (years * SECONDS_PER_YEAR);
+	}
 
-	unsigned long weeks = (duration / 604800) % 52;
+	const auto weeks = (duration / SECONDS_PER_WEEK);
 	if (weeks)
-		ret += ConvToStr(weeks) + "w";
+	{
+		ret += INSP_FORMAT("{}w", weeks);
+		duration -= (weeks * SECONDS_PER_WEEK);
+	}
 
-	unsigned long days = (duration / 86400) % 7;
+	const auto days = (duration / SECONDS_PER_DAY);
 	if (days)
-		ret += ConvToStr(days) + "d";
+	{
+		ret += INSP_FORMAT("{}d", days);
+		duration -= (days * SECONDS_PER_DAY);
+	}
 
-	unsigned long hours = (duration / 3600) % 24;
+	const auto hours = (duration / SECONDS_PER_HOUR);
 	if (hours)
-		ret += ConvToStr(hours) + "h";
+	{
+		ret += INSP_FORMAT("{}h", hours);
+		duration -= (hours * SECONDS_PER_HOUR);
+	}
 
-	unsigned long minutes = (duration / 60) % 60;
+	const auto minutes = (duration / SECONDS_PER_MINUTE);
 	if (minutes)
-		ret += ConvToStr(minutes) + "m";
+	{
+		ret += INSP_FORMAT("{}m", minutes);
+		duration -= (minutes * SECONDS_PER_MINUTE);
+	}
 
-	unsigned long seconds = duration % 60;
-	if (seconds)
-		ret += ConvToStr(seconds) + "s";
+	if (duration)
+		ret += INSP_FORMAT("{}s", duration);
 
 	return ret;
 }