Add Weekend Outlook generation

internal/briefing/weekend.go

@@ -0,0 +1,125 @@
+package briefing
+
+import (
+	"fmt"
+	"strings"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/forecast"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/report"
+)
+
+type Weekend struct {
+	Days           []OutlookDay            `json:"days"`
+	Planning       WeekendPlanning         `json:"planning"`
+	RelevantAlerts []forecast.AlertOverlap `json:"relevantAlerts,omitempty"`
+	Discussion     DiscussionContext       `json:"discussion,omitempty"`
+	WeatherStory   *WeatherStoryContext    `json:"weatherStory,omitempty"`
+}
+
+type WeekendPlanning struct {
+	BestOutdoorWindows  []OutdoorWindow `json:"bestOutdoorWindows,omitempty"`
+	WorstWeatherWindows []OutdoorWindow `json:"worstWeatherWindows,omitempty"`
+	RainStormTiming     []string        `json:"rainStormTiming,omitempty"`
+	ComfortConcerns     []string        `json:"comfortConcerns,omitempty"`
+	UncertaintyInputs   []string        `json:"uncertaintyInputs,omitempty"`
+}
+
+func BuildWeekend(ctx BuildContext, summaries []forecast.DailySummary) (Package, error) {
+	if ctx.Resolved.Definition.ID != report.Weekend {
+		return Package{}, fmt.Errorf("weekend briefing requires a weekend report definition")
+	}
+	if len(summaries) == 0 {
+		return Package{}, fmt.Errorf("weekend forecast summaries are required")
+	}
+	pkg := Package{
+		Metadata: BuildMetadata(ctx),
+		Weekend: &Weekend{
+			Discussion:   buildDiscussion(summaries[0].Discussion),
+			WeatherStory: buildWeatherStory(ctx.Bundle),
+		},
+	}
+	for _, summary := range summaries {
+		pkg.Weekend.Days = append(pkg.Weekend.Days, buildOutlookDay(summary))
+	}
+	pkg.Weekend.RelevantAlerts = collectOutlookAlerts(pkg.Weekend.Days)
+	pkg.Weekend.Planning = buildWeekendPlanning(pkg.Weekend.Days, pkg.Weekend.Discussion, ctx.Bundle)
+	return pkg, nil
+}
+
+func buildWeekendPlanning(days []OutlookDay, discussion DiscussionContext, bundle *forecast.Bundle) WeekendPlanning {
+	planning := WeekendPlanning{}
+	for _, day := range days {
+		if day.OutdoorWindows.Best != nil {
+			window := *day.OutdoorWindows.Best
+			window.Daypart = day.Date + " " + window.Daypart
+			planning.BestOutdoorWindows = append(planning.BestOutdoorWindows, window)
+		}
+		if day.OutdoorWindows.Worst != nil {
+			window := *day.OutdoorWindows.Worst
+			window.Daypart = day.Date + " " + window.Daypart
+			planning.WorstWeatherWindows = append(planning.WorstWeatherWindows, window)
+		}
+		for _, daypart := range day.Dayparts {
+			planning.RainStormTiming = appendUnique(planning.RainStormTiming, weekendRainStormNotes(day.Date, daypart)...)
+			planning.ComfortConcerns = appendUnique(planning.ComfortConcerns, weekendComfortNotes(day.Date, daypart)...)
+		}
+	}
+	planning.UncertaintyInputs = appendUnique(planning.UncertaintyInputs, discussion.KeyMessages...)
+	if discussion.ShortTerm != "" {
+		planning.UncertaintyInputs = appendUnique(planning.UncertaintyInputs, "Short-term discussion available for confidence context.")
+	}
+	if discussion.LongTerm != "" {
+		planning.UncertaintyInputs = appendUnique(planning.UncertaintyInputs, "Long-term discussion available for uncertainty context.")
+	}
+	if bundle != nil {
+		for _, warning := range bundle.Warnings {
+			if warning.Code != "" {
+				planning.UncertaintyInputs = appendUnique(planning.UncertaintyInputs, "Source warning: "+warning.Code+".")
+			}
+		}
+	}
+	if len(planning.RainStormTiming) == 0 {
+		planning.RainStormTiming = append(planning.RainStormTiming, "No focused rain or storm timing stands out in the available weekend forecast.")
+	}
+	if len(planning.ComfortConcerns) == 0 {
+		planning.ComfortConcerns = append(planning.ComfortConcerns, "No major heat, cold, or wind comfort concern stands out in the available weekend forecast.")
+	}
+	if len(planning.UncertaintyInputs) == 0 {
+		planning.UncertaintyInputs = append(planning.UncertaintyInputs, "No explicit confidence or uncertainty signal was available from the selected source context.")
+	}
+	return planning
+}
+
+func weekendRainStormNotes(date string, daypart forecast.DaypartSummary) []string {
+	notes := []string{}
+	label := weekendWindowLabel(date, daypart.Name)
+	if daypart.MaxPrecipitationProbability != nil && daypart.MaxPrecipitationProbability.Value >= 30 {
+		notes = append(notes, fmt.Sprintf("%s precipitation chance peaks near %.0f%%.", label, daypart.MaxPrecipitationProbability.Value))
+	}
+	if daypart.Indicators.Thunder {
+		notes = append(notes, label+" thunder risk is present.")
+	}
+	return notes
+}
+
+func weekendComfortNotes(date string, daypart forecast.DaypartSummary) []string {
+	notes := []string{}
+	label := weekendWindowLabel(date, daypart.Name)
+	if daypart.Indicators.Heat {
+		notes = append(notes, label+" heat may affect outdoor comfort.")
+	}
+	if daypart.Indicators.Cold {
+		notes = append(notes, label+" cold may affect outdoor comfort.")
+	}
+	if daypart.PeakWindGust != nil && daypart.PeakWindGust.Value >= 25 {
+		notes = append(notes, fmt.Sprintf("%s gusts may reach %.0f mph.", label, daypart.PeakWindGust.Value))
+	}
+	return notes
+}
+
+func weekendWindowLabel(date string, daypart string) string {
+	if daypart == "" {
+		return date
+	}
+	return strings.TrimSpace(date + " " + daypart)
+}