feat(stats): show work and time-off lengths (#66)

src/app/services/leave-planner.core.ts

@@ -460,6 +460,9 @@ export interface PlanningMetrics {
 	holidayWeekValue: number;
 	nonWorkingDayGain: number;
 	longestWorkSequence: number;
+	averageWorkSequence: number | null;
+	averageTimeOffPeriod: number | null;
+	longestTimeOffPeriod: number | null;
 	shortSequenceDeficit: number;
 	supportingPlacements: number;
 	preferenceSatisfaction: number[];
@@ -5026,6 +5029,7 @@ function qualityMetrics(
 		} else current++;
 	}
 	if (context.workingDays.length) sequences.push(current);
+	const nonEmptySequences = sequences.filter((length) => length > 0);
 	const internal = hasTimeOff ? sequences.slice(1, -1) : [];
 	const shortSequenceDeficit = internal.reduce(
 		(sum, length) => sum + (length > 0 && length < 5 ? 5 - length : 0),
@@ -5036,6 +5040,15 @@ function qualityMetrics(
 		holidayWeekValue: holidayWeekValue(state, context),
 		nonWorkingDayGain: periods.reduce((sum, period) => sum + period.nonWorkingDayGain, 0),
 		longestWorkSequence: sequences.length ? Math.max(...sequences) : 0,
+		averageWorkSequence: nonEmptySequences.length
+			? nonEmptySequences.reduce((sum, length) => sum + length, 0) / nonEmptySequences.length
+			: null,
+		averageTimeOffPeriod: periods.length
+			? periods.reduce((sum, period) => sum + period.duration, 0) / periods.length
+			: null,
+		longestTimeOffPeriod: periods.length
+			? Math.max(...periods.map((period) => period.duration))
+			: null,
 		shortSequenceDeficit,
 		supportingPlacements: [...state.placements.values()].filter(
 			(placement) => placement.supporting,