add theming

cmd/root.go

@@ -5,7 +5,9 @@ import (
 	"net"
 	"os"
 	"path/filepath"
+	"slices"
 	"sort"
+	"strings"
 	"time"
 
 	"github.com/mr0xb/nxstats/internal/geo"
@@ -22,13 +24,14 @@ var (
 	flagNoGzip     bool
 	flagGeoIP      string
 	flagSplitByDay bool
+	flagTheme      string
 )
 
 var rootCmd = &cobra.Command{
 	Use:   "nxstats",
 	Short: "Nginx log parser and HTML report generator",
 	Long: `nxstats parses nginx access and error logs (including gzip-compressed
-rotated logs) and generates a rich cyberpunk-themed HTML report with
+rotated logs) and generates a rich themeable HTML report with
 charts, searchable tables, and optional GeoIP2 hit maps.`,
 	RunE: runE,
 }
@@ -41,6 +44,17 @@ func init() {
 	rootCmd.Flags().BoolVar(&flagNoGzip, "no-gzip", false, "Skip .gz compressed rotated logs")
 	rootCmd.Flags().StringVar(&flagGeoIP, "geoip", "", "Path to MaxMind GeoLite2-City.mmdb (enables map)")
 	rootCmd.Flags().BoolVar(&flagSplitByDay, "split-by-day", false, "Write one HTML report per calendar day plus an index page")
+	rootCmd.Flags().StringVar(&flagTheme, "theme", report.DefaultTheme,
+		"Report visual theme ("+strings.Join(report.ThemeNames(), ", ")+")")
+}
+
+// validateTheme returns an error if name is not a recognized theme.
+func validateTheme(name string) error {
+	valid := report.ThemeNames()
+	if slices.Contains(valid, name) {
+		return nil
+	}
+	return fmt.Errorf("invalid --theme %q: must be one of %s", name, strings.Join(valid, ", "))
 }
 
 // Execute runs the root command.
@@ -51,6 +65,10 @@ func Execute() {
 }
 
 func runE(cmd *cobra.Command, args []string) error {
+	if err := validateTheme(flagTheme); err != nil {
+		return err
+	}
+
 	accessFiles, errorFiles, err := resolveLogFiles()
 	if err != nil {
 		return err
@@ -89,6 +107,7 @@ func runE(cmd *cobra.Command, args []string) error {
 		GeneratedAt:   time.Now(),
 		AccessEntries: accessEntries,
 		ErrorEntries:  errorEntries,
+		Theme:         flagTheme,
 	}
 	report.ComputeStats(&data)
 
@@ -184,7 +203,7 @@ func runSplitByDay(
 ) error {
 	indexBase := filepath.Base(flagOutput)
 
-	days := report.GroupByDay(flagOutput, accessEntries, errorEntries, geoPoints)
+	days := report.GroupByDay(flagOutput, accessEntries, errorEntries, geoPoints, flagTheme)
 	if len(days) == 0 {
 		fmt.Fprintln(os.Stderr, "nxstats: no entries found, writing empty index")
 	}
@@ -287,5 +306,6 @@ func buildIndexData(allAccess []parser.AccessEntry, days []report.DayReport) rep
 		TotalUniqueIPs:   len(ipSet),
 		TotalBytes:       totalBytes,
 		OverallErrorRate: errorRate,
+		Theme:            flagTheme,
 	}
 }