Add Tomorrow planning brief generation

internal/briefing/daily.go

@@ -15,6 +15,7 @@ type Daily struct {
 	Dayparts            []forecast.DaypartSummary `json:"dayparts"`
 	RelevantAlerts      []forecast.AlertOverlap   `json:"relevantAlerts,omitempty"`
 	OutdoorWindows      OutdoorWindows            `json:"outdoorWindows"`
+	Planning            *TomorrowPlanning         `json:"planning,omitempty"`
 	NarrativePeriods    []forecast.ForecastPeriod `json:"narrativePeriods,omitempty"`
 	Discussion          DiscussionContext         `json:"discussion,omitempty"`
 	WeatherStory        *WeatherStoryContext      `json:"weatherStory,omitempty"`
@@ -42,6 +43,12 @@ type OutdoorWindow struct {
 	Score   float64  `json:"score"`
 }
 
+type TomorrowPlanning struct {
+	MorningReadiness             []string `json:"morningReadiness,omitempty"`
+	CommuteSchoolWorkdayConcerns []string `json:"commuteSchoolWorkdayConcerns,omitempty"`
+	OvernightChangeWatch         []string `json:"overnightChangeWatch,omitempty"`
+}
+
 type DiscussionContext struct {
 	Product     string   `json:"product,omitempty"`
 	KeyMessages []string `json:"keyMessages,omitempty"`
@@ -74,6 +81,9 @@ func BuildDaily(ctx BuildContext, summary *forecast.DailySummary) (Package, erro
 			ForecastSummaryDate: summary.Date,
 		},
 	}
+	if ctx.Resolved.Definition.ID == report.DailyTomorrow {
+		pkg.Daily.Planning = buildTomorrowPlanning(summary)
+	}
 	return pkg, nil
 }
 
@@ -122,6 +132,124 @@ func buildOutdoorWindows(dayparts []forecast.DaypartSummary) OutdoorWindows {
 	return OutdoorWindows{Best: best, Worst: worst}
 }
 
+func buildTomorrowPlanning(summary *forecast.DailySummary) *TomorrowPlanning {
+	planning := &TomorrowPlanning{}
+	morning := daypartNamed(summary.Dayparts, "morning")
+	if morning != nil {
+		planning.MorningReadiness = append(planning.MorningReadiness, readinessNotes(*morning)...)
+	}
+	if len(planning.MorningReadiness) == 0 {
+		planning.MorningReadiness = append(planning.MorningReadiness, "Morning weather looks routine based on the available hourly forecast.")
+	}
+
+	for _, daypart := range summary.Dayparts {
+		if daypart.Name == "overnight" || daypart.Name == "evening" {
+			continue
+		}
+		planning.CommuteSchoolWorkdayConcerns = appendUnique(planning.CommuteSchoolWorkdayConcerns, concernNotes(daypart)...)
+	}
+	for _, alert := range summary.AlertOverlaps {
+		if alert.Event != "" {
+			planning.CommuteSchoolWorkdayConcerns = appendUnique(planning.CommuteSchoolWorkdayConcerns, "Active alert to plan around: "+alert.Event+".")
+		}
+	}
+	if len(planning.CommuteSchoolWorkdayConcerns) == 0 {
+		planning.CommuteSchoolWorkdayConcerns = append(planning.CommuteSchoolWorkdayConcerns, "No major commute, school, or workday weather concerns stand out in the available forecast.")
+	}
+
+	overnight := daypartNamed(summary.Dayparts, "overnight")
+	if overnight != nil {
+		planning.OvernightChangeWatch = append(planning.OvernightChangeWatch, overnightWatchNotes(*overnight)...)
+	}
+	if len(planning.OvernightChangeWatch) == 0 {
+		planning.OvernightChangeWatch = append(planning.OvernightChangeWatch, "Watch for forecast timing or intensity adjustments overnight.")
+	}
+
+	return planning
+}
+
+func readinessNotes(daypart forecast.DaypartSummary) []string {
+	notes := []string{}
+	if daypart.MaxPrecipitationProbability != nil && daypart.MaxPrecipitationProbability.Value >= 50 {
+		notes = append(notes, fmt.Sprintf("Morning precipitation chance peaks near %.0f%%.", daypart.MaxPrecipitationProbability.Value))
+	}
+	if daypart.PeakWindGust != nil && daypart.PeakWindGust.Value >= 30 {
+		notes = append(notes, fmt.Sprintf("Morning gusts may reach %.0f mph.", daypart.PeakWindGust.Value))
+	}
+	if daypart.Indicators.Thunder {
+		notes = append(notes, "Morning thunder could affect departure timing.")
+	}
+	if daypart.Indicators.Snow || daypart.Indicators.Ice {
+		notes = append(notes, "Morning wintry weather could affect surfaces and travel.")
+	}
+	if daypart.Indicators.Fog {
+		notes = append(notes, "Morning fog could reduce visibility.")
+	}
+	if daypart.Temperature.Min != nil && *daypart.Temperature.Min <= 32 {
+		notes = append(notes, "Morning temperatures may be at or below freezing.")
+	}
+	return appendUnique(nil, notes...)
+}
+
+func concernNotes(daypart forecast.DaypartSummary) []string {
+	notes := []string{}
+	prefix := titleWord(daypart.Name)
+	if prefix == "" {
+		prefix = "Daytime"
+	}
+	if daypart.MaxPrecipitationProbability != nil && daypart.MaxPrecipitationProbability.Value >= 40 {
+		notes = append(notes, fmt.Sprintf("%s precipitation chance reaches %.0f%%.", prefix, daypart.MaxPrecipitationProbability.Value))
+	}
+	if daypart.PeakWindGust != nil && daypart.PeakWindGust.Value >= 30 {
+		notes = append(notes, fmt.Sprintf("%s gusts may reach %.0f mph.", prefix, daypart.PeakWindGust.Value))
+	}
+	if daypart.Indicators.Thunder {
+		notes = append(notes, prefix+" thunder may disrupt outdoor plans.")
+	}
+	if daypart.Indicators.Snow || daypart.Indicators.Ice {
+		notes = append(notes, prefix+" wintry weather may affect travel.")
+	}
+	if daypart.Indicators.Heat {
+		notes = append(notes, prefix+" heat may require extra hydration and breaks.")
+	}
+	if daypart.Indicators.Cold {
+		notes = append(notes, prefix+" cold may require extra layers.")
+	}
+	if len(daypart.AlertOverlaps) > 0 {
+		notes = append(notes, prefix+" alert overlap needs attention.")
+	}
+	return appendUnique(nil, notes...)
+}
+
+func overnightWatchNotes(daypart forecast.DaypartSummary) []string {
+	notes := []string{}
+	if daypart.MaxPrecipitationProbability != nil && daypart.MaxPrecipitationProbability.Value >= 30 {
+		notes = append(notes, fmt.Sprintf("Overnight precipitation timing may shift; current peak is near %.0f%%.", daypart.MaxPrecipitationProbability.Value))
+	}
+	if daypart.PeakWindGust != nil && daypart.PeakWindGust.Value >= 30 {
+		notes = append(notes, fmt.Sprintf("Overnight gusts may reach %.0f mph before morning plans begin.", daypart.PeakWindGust.Value))
+	}
+	if daypart.Indicators.Thunder {
+		notes = append(notes, "Overnight storms could change morning impacts.")
+	}
+	if daypart.Indicators.Snow || daypart.Indicators.Ice {
+		notes = append(notes, "Overnight wintry weather could leave morning travel impacts.")
+	}
+	if len(daypart.AlertOverlaps) > 0 {
+		notes = append(notes, "Overnight alert timing could affect the morning setup.")
+	}
+	return appendUnique(nil, notes...)
+}
+
+func daypartNamed(dayparts []forecast.DaypartSummary, name string) *forecast.DaypartSummary {
+	for i := range dayparts {
+		if strings.EqualFold(dayparts[i].Name, name) {
+			return &dayparts[i]
+		}
+	}
+	return nil
+}
+
 func buildDiscussion(discussion *forecast.Discussion) DiscussionContext {
 	if discussion == nil {
 		return DiscussionContext{}
@@ -276,3 +404,28 @@ func dedupe(values []string) []string {
 	}
 	return out
 }
+
+func appendUnique(values []string, candidates ...string) []string {
+	seen := map[string]struct{}{}
+	for _, value := range values {
+		seen[value] = struct{}{}
+	}
+	for _, candidate := range candidates {
+		if candidate == "" {
+			continue
+		}
+		if _, ok := seen[candidate]; ok {
+			continue
+		}
+		seen[candidate] = struct{}{}
+		values = append(values, candidate)
+	}
+	return values
+}
+
+func titleWord(value string) string {
+	if value == "" {
+		return ""
+	}
+	return strings.ToUpper(value[:1]) + value[1:]
+}