Add Daily briefing JSON generation

internal/briefing/package.go

@@ -0,0 +1,156 @@
+// Package briefing builds report-specific structured briefing packages.
+package briefing
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"path/filepath"
+	"time"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/forecast"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/report"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/timeutil"
+)
+
+const SchemaVersion = "weatherreporter.briefing.v1"
+
+type Package struct {
+	Metadata Metadata `json:"metadata"`
+	Daily    *Daily   `json:"daily,omitempty"`
+}
+
+type Metadata struct {
+	SchemaVersion    string                   `json:"schemaVersion"`
+	RunID            string                   `json:"runId"`
+	ReportID         report.ID                `json:"reportId"`
+	Variant          string                   `json:"variant,omitempty"`
+	PromptID         string                   `json:"promptId"`
+	GeneratedAt      time.Time                `json:"generatedAt"`
+	Units            string                   `json:"units"`
+	Timezone         string                   `json:"timezone"`
+	ValidPeriod      timeutil.Period          `json:"validPeriod"`
+	SourceLocationID string                   `json:"sourceLocationId,omitempty"`
+	SourceLocation   string                   `json:"sourceLocation,omitempty"`
+	Sources          []SourceMetadata         `json:"sources,omitempty"`
+	SourceWarnings   []forecast.SourceWarning `json:"sourceWarnings,omitempty"`
+}
+
+type SourceMetadata struct {
+	Name       string                   `json:"name"`
+	Endpoint   string                   `json:"endpoint,omitempty"`
+	FetchedAt  time.Time                `json:"fetchedAt"`
+	IssuedAt   *time.Time               `json:"issuedAt,omitempty"`
+	UpdatedAt  *time.Time               `json:"updatedAt,omitempty"`
+	DataSHA256 string                   `json:"dataSha256,omitempty"`
+	Missing    bool                     `json:"missing,omitempty"`
+	Warnings   []forecast.SourceWarning `json:"warnings,omitempty"`
+}
+
+type BuildContext struct {
+	Resolved report.Resolved
+	Bundle   *forecast.Bundle
+	Units    string
+	Timezone string
+}
+
+func BuildMetadata(ctx BuildContext) Metadata {
+	metadata := ctx.Resolved.Metadata()
+	sourceLocationID, sourceLocation := sourceLocation(ctx.Bundle)
+	return Metadata{
+		SchemaVersion:    SchemaVersion,
+		RunID:            metadata.RunID,
+		ReportID:         metadata.ReportID,
+		Variant:          variantForReport(metadata.ReportID),
+		PromptID:         metadata.PromptID,
+		GeneratedAt:      metadata.GeneratedAt,
+		Units:            ctx.Units,
+		Timezone:         ctx.Timezone,
+		ValidPeriod:      metadata.ValidPeriod,
+		SourceLocationID: sourceLocationID,
+		SourceLocation:   sourceLocation,
+		Sources:          sourceMetadata(ctx.Bundle),
+		SourceWarnings:   sourceWarnings(ctx.Bundle),
+	}
+}
+
+func Save(path string, pkg Package) error {
+	data, err := json.MarshalIndent(pkg, "", "  ")
+	if err != nil {
+		return fmt.Errorf("marshal briefing package: %w", err)
+	}
+	if err := os.MkdirAll(filepath.Dir(path), 0o755); err != nil {
+		return fmt.Errorf("create briefing directory %q: %w", filepath.Dir(path), err)
+	}
+	tmp, err := os.CreateTemp(filepath.Dir(path), "."+filepath.Base(path)+".*.tmp")
+	if err != nil {
+		return fmt.Errorf("create temporary briefing file: %w", err)
+	}
+	tmpName := tmp.Name()
+	defer os.Remove(tmpName)
+
+	if _, err := tmp.Write(data); err != nil {
+		tmp.Close()
+		return fmt.Errorf("write temporary briefing file: %w", err)
+	}
+	if err := tmp.Close(); err != nil {
+		return fmt.Errorf("close temporary briefing file: %w", err)
+	}
+	if err := os.Rename(tmpName, path); err != nil {
+		return fmt.Errorf("save briefing %q: %w", path, err)
+	}
+	return nil
+}
+
+func sourceLocation(bundle *forecast.Bundle) (string, string) {
+	if bundle == nil {
+		return "", ""
+	}
+	for _, run := range []*forecast.ForecastRun{bundle.Hourly, bundle.Narrative, bundle.Daily} {
+		if run == nil {
+			continue
+		}
+		if run.LocationID != "" || run.LocationName != "" {
+			return run.LocationID, run.LocationName
+		}
+	}
+	return "", ""
+}
+
+func sourceMetadata(bundle *forecast.Bundle) []SourceMetadata {
+	if bundle == nil {
+		return nil
+	}
+	out := make([]SourceMetadata, 0, len(bundle.Sources))
+	for _, source := range bundle.Sources {
+		out = append(out, SourceMetadata{
+			Name:       source.Name,
+			Endpoint:   source.Endpoint,
+			FetchedAt:  source.FetchedAt,
+			IssuedAt:   source.IssuedAt,
+			UpdatedAt:  source.UpdatedAt,
+			DataSHA256: source.DataSHA256,
+			Missing:    source.Missing,
+			Warnings:   source.Warnings,
+		})
+	}
+	return out
+}
+
+func sourceWarnings(bundle *forecast.Bundle) []forecast.SourceWarning {
+	if bundle == nil {
+		return nil
+	}
+	return bundle.Warnings
+}
+
+func variantForReport(id report.ID) string {
+	switch id {
+	case report.DailyToday:
+		return "today"
+	case report.DailyTomorrow:
+		return "tomorrow"
+	default:
+		return ""
+	}
+}