Support near-term derived facts

internal/briefing/derived_modules_test.go

@@ -136,6 +136,22 @@ func TestPrecipTimingModuleHandlesRainyAndDryForecasts(t *testing.T) {
 	}
 }
 
+func TestPrecipTimingModuleUsesDerivedTimingWithoutDaypartSummaries(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	ctx := derivedModuleContext(report.NearTerm)
+	ctx.Derived.DailySummaries = nil
+	ctx.Derived.DaypartSummaries = nil
+
+	output, err := registry.BuildModule(ctx, module.ConfigItem{ID: module.PrecipTiming})
+	if err != nil {
+		t.Fatalf("BuildModule() error = %v", err)
+	}
+	value := moduleValue[PrecipTimingModule](t, output)
+	if value.MaxPopPercent == nil || *value.MaxPopPercent != 80 || len(value.PrecipitationWindows) != 2 {
+		t.Fatalf("precip timing = %#v, want derived timing without daypart summaries", value)
+	}
+}
+
 func TestDerivedDaypartSummariesExposeConfiguredKeysAndHazards(t *testing.T) {
 	registry := MustDefaultModuleRegistry()
 	ctx := derivedModuleContext(report.DailyToday)

internal/briefing/modules.go

@@ -312,7 +312,7 @@ func defaultModuleDefinitions() []ModuleDefinition {
 			ID:               module.PrecipTiming,
 			StanzaName:       "precip_timing",
 			DefaultOptions:   module.PrecipTimingOptions{},
-			RequiredDerived:  []module.FactRequirement{module.RequiresDerivedDaypartSummaries},
+			RequiredDerived:  []module.FactRequirement{module.RequiresDerivedPrecipTiming},
 			SupportedReports: allReports,
 			MissingData:      module.MissingDataEmpty,
 			Builder:          buildPrecipTimingModule,

internal/facts/facts.go

@@ -114,6 +114,7 @@ func BuildDerived(req BuildDerivedRequest) (DerivedFacts, error) {
 	derived.PrecipTiming = forecast.BuildPrecipTiming(derived.ValidPeriodHourlyPeriods)
 
 	switch req.Resolved.Definition.ID {
+	case report.NearTerm:
 	case report.DailyToday, report.DailyTomorrow:
 		summary, err := forecast.BuildDailySummary(bundle, period.Start, location, req.Dayparts)
 		if err != nil {

internal/facts/facts_test.go

@@ -152,6 +152,63 @@ func TestBuildDerivedWeekendAndTomorrow(t *testing.T) {
 	}
 }
 
+func TestBuildDerivedNearTermUsesRollingWindowFacts(t *testing.T) {
+	location := testLocation()
+	resolved := resolveForTest(t, report.NearTerm, mustParse("2026-05-29T08:30:00-05:00"), location)
+	bundle := testBundle(location)
+	bundle.Alerts = &weatherdata.AlertRun{Alerts: []json.RawMessage{
+		json.RawMessage(`{"event":"Expired Advisory","headline":"Ends at start","severity":"Minor","effective":"2026-05-29T05:00:00-05:00","expires":"2026-05-29T08:30:00-05:00"}`),
+		json.RawMessage(`{"event":"Flood Watch","headline":"Flooding possible","severity":"Moderate","effective":"2026-05-29T11:00:00-05:00","expires":"2026-05-29T15:00:00-05:00"}`),
+		json.RawMessage(`{"event":"Evening Advisory","headline":"Starts at end","severity":"Minor","effective":"2026-05-29T14:30:00-05:00","expires":"2026-05-29T18:00:00-05:00"}`),
+	}}
+	bundle.SPCConvectiveOutlooks = testConvectiveOutlookRun(location)
+
+	derived, err := BuildDerived(BuildDerivedRequest{
+		Resolved:  resolved,
+		Timezone:  location.String(),
+		Dayparts:  testDayparts(),
+		Collected: BuildCollected(bundle),
+	})
+	if err != nil {
+		t.Fatalf("BuildDerived() error = %v", err)
+	}
+
+	if len(derived.ValidPeriodHourlyPeriods) != 4 {
+		t.Fatalf("ValidPeriodHourlyPeriods length = %d, want 4 rolling-window hours", len(derived.ValidPeriodHourlyPeriods))
+	}
+	if derived.ValidPeriodHourlyPeriods[0].StartTime.Format(time.RFC3339) != "2026-05-29T08:00:00-05:00" ||
+		derived.ValidPeriodHourlyPeriods[3].StartTime.Format(time.RFC3339) != "2026-05-29T14:00:00-05:00" {
+		t.Fatalf("ValidPeriodHourlyPeriods = %#v, want only hours overlapping 8:30 AM-2:30 PM", derived.ValidPeriodHourlyPeriods)
+	}
+	if len(derived.ValidPeriodNarrativePeriods) != 1 {
+		t.Fatalf("ValidPeriodNarrativePeriods length = %d, want overlapping narrative period", len(derived.ValidPeriodNarrativePeriods))
+	}
+	if len(derived.DailySummaries) != 0 || len(derived.DaypartSummaries) != 0 || derived.StormWindowSummary != nil {
+		t.Fatalf("near-term summaries daily=%#v daypart=%#v storm=%#v, want none", derived.DailySummaries, derived.DaypartSummaries, derived.StormWindowSummary)
+	}
+	if derived.PrecipTiming.FirstPrecipitation == nil || derived.PrecipTiming.FirstPrecipitation.Time.Format(time.RFC3339) != "2026-05-29T08:00:00-05:00" {
+		t.Fatalf("PrecipTiming.FirstPrecipitation = %#v, want first selected rainy hour", derived.PrecipTiming.FirstPrecipitation)
+	}
+	if derived.PrecipTiming.LastPrecipitation == nil || derived.PrecipTiming.LastPrecipitation.Time.Format(time.RFC3339) != "2026-05-29T14:00:00-05:00" {
+		t.Fatalf("PrecipTiming.LastPrecipitation = %#v, want final selected rainy window end", derived.PrecipTiming.LastPrecipitation)
+	}
+	if len(derived.PrecipTiming.PrecipitationWindows) != 2 {
+		t.Fatalf("PrecipTiming.PrecipitationWindows = %#v, want two near-term windows", derived.PrecipTiming.PrecipitationWindows)
+	}
+	if len(derived.AlertOverlaps) != 1 || derived.AlertOverlaps[0].Event != "Flood Watch" {
+		t.Fatalf("AlertOverlaps = %#v, want only alert overlapping near-term period", derived.AlertOverlaps)
+	}
+	if derived.AlertOverlaps[0].Overlap.End.Format(time.RFC3339) != "2026-05-29T14:30:00-05:00" {
+		t.Fatalf("Alert overlap end = %s, want clipped to near-term end", derived.AlertOverlaps[0].Overlap.End.Format(time.RFC3339))
+	}
+	if got, want := outlookIDs(derived.SPCConvectiveOutlooks), []string{"fri-high", "fri-storm", "fri-low", "fri-missing-rank", "fri-probabilistic"}; strings.Join(got, ",") != strings.Join(want, ",") {
+		t.Fatalf("SPCConvectiveOutlooks IDs = %#v, want %#v", got, want)
+	}
+	if got, want := discussionHeadlines(derived.SPCConvectiveDiscussions), []string{"day1 early", "day1 late"}; strings.Join(got, ",") != strings.Join(want, ",") {
+		t.Fatalf("SPCConvectiveDiscussions = %#v, want retained discussions for overlapping SPC day %#v", got, want)
+	}
+}
+
 func TestBuildDerivedStormBuildsWindowSummary(t *testing.T) {
 	location := testLocation()
 	resolved := resolveStormForTest(t, location)
@@ -247,6 +304,22 @@ func TestBuildDerivedSelectsSPCConvectiveOutlooksByValidPeriod(t *testing.T) {
 	}
 }
 
+func TestBuildDerivedUnsupportedReportReturnsActionableError(t *testing.T) {
+	location := testLocation()
+	resolved := resolveForTest(t, report.NearTerm, mustParse("2026-05-29T08:00:00-05:00"), location)
+	resolved.Definition.ID = report.ID("future_report")
+
+	_, err := BuildDerived(BuildDerivedRequest{
+		Resolved:  resolved,
+		Timezone:  location.String(),
+		Dayparts:  testDayparts(),
+		Collected: BuildCollected(testBundle(location)),
+	})
+	if err == nil || !strings.Contains(err.Error(), `derived facts are not implemented for report "future_report"`) {
+		t.Fatalf("BuildDerived() error = %v, want actionable unsupported report error", err)
+	}
+}
+
 func TestBuildDerivedSPCConvectiveOutlooksDistinguishesMissingAndCheckedEmpty(t *testing.T) {
 	location := testLocation()
 	resolved := resolveForTest(t, report.DailyToday, mustParse("2026-05-29T08:00:00-05:00"), location)