1 files changed, 84 insertions, 0 deletions
diff --git a/internal/cli/liturgy.go b/internal/cli/liturgy.go
new file mode 100644
index 0000000..523531d
--- /dev/null
+++ b/internal/cli/liturgy.go
@@ -0,0 +1,84 @@
+package cli
+
+import (
+	"fmt"
+	"io"
+	"strings"
+	"time"
+
+	"github.com/lukaszkasprzak/lectio/internal/caldata"
+	"github.com/lukaszkasprzak/lectio/internal/calendar"
+	"github.com/lukaszkasprzak/lectio/internal/config"
+)
+
+// runLiturgy prints the computed liturgical day for date (default today) using
+// the offline calendar engine, and exits. It is the engine's demo/validation
+// surface; the daily-readings paths still use the scraper.
+func runLiturgy(cfg config.Config, date string, stdout, stderr io.Writer) int {
+	if date == "" {
+		date = today()
+	}
+	d, err := time.Parse("2006-01-02", date)
+	if err != nil {
+		fmt.Fprintf(stderr, "lectio: bad date %q (want YYYY-MM-DD)\n", date)
+		return 2
+	}
+	day := calendar.Compute(d.UTC(), cfg.Selection(), []calendar.Layer{caldata.Universal()})
+	printLiturgicalDay(stdout, cfg, day)
+	return 0
+}
+
+func printLiturgicalDay(out io.Writer, cfg config.Config, day calendar.LiturgicalDay) {
+	fmt.Fprintf(out, "%s  %s\n", day.Date.Format("2006-01-02"), day.Weekday.String())
+	fmt.Fprintf(out, "season:   %s (week %d · Sunday cycle %s · weekday cycle %s)\n",
+		day.Season, day.Week, day.SundayCycle, day.WeekdayCycle)
+	fmt.Fprintf(out, "observed: %s  [%s · %s]\n", celebrationName(cfg, day.Observed), rankLabel(day.Observed.Rank), day.Colour)
+	for _, o := range day.Others {
+		if n := celebrationName(cfg, o); n != "" {
+			fmt.Fprintf(out, "  also:   %s  [%s]\n", n, rankLabel(o.Rank))
+		}
+	}
+	for _, m := range day.Observed.Masses {
+		for _, r := range m.Readings {
+			label := r.Part
+			if m.Variant != "" {
+				label = m.Variant + " " + label
+			}
+			fmt.Fprintf(out, "  %-16s %s\n", label+":", r.Citation)
+		}
+	}
+}
+
+// celebrationName is the celebration's name in the UI language (falling back to
+// English, then a humanized slug for temporal days that carry no proper name).
+func celebrationName(cfg config.Config, c calendar.Celebration) string {
+	lang := "en"
+	if cfg.UILanguage == "pl" {
+		lang = "pl"
+	}
+	if n := c.Name[lang]; n != "" {
+		return n
+	}
+	if n := c.Name["en"]; n != "" {
+		return n
+	}
+	if c.Slug == "" {
+		return "(feria)"
+	}
+	return strings.ReplaceAll(c.Slug, "-", " ")
+}
+
+func rankLabel(r calendar.Rank) string {
+	switch r {
+	case calendar.RankSolemnity:
+		return "solemnity"
+	case calendar.RankFeast:
+		return "feast"
+	case calendar.RankMemorial:
+		return "memorial"
+	case calendar.RankOptional:
+		return "optional memorial"
+	default:
+		return "feria"
+	}
+}