Add more features to clock

internal/widget/clock.go

@@ -1,23 +1,50 @@
 package widget
 
 import (
-	"context"
+	"errors"
+	"fmt"
 	"html/template"
+	"time"
 
 	"github.com/glanceapp/glance/internal/assets"
 )
 
 type Clock struct {
 	widgetBase `yaml:",inline"`
+	cachedHTML template.HTML `yaml:"-"`
+	HourFormat string        `yaml:"hour-format"`
+	Timezones  []struct {
+		Timezone string `yaml:"timezone"`
+		Label    string `yaml:"label"`
+	} `yaml:"timezones"`
 }
 
 func (widget *Clock) Initialize() error {
 	widget.withTitle("Clock").withError(nil)
+
+	if widget.HourFormat == "" {
+		widget.HourFormat = "24h"
+	} else if widget.HourFormat != "12h" && widget.HourFormat != "24h" {
+		return errors.New("invalid hour format for clock widget, must be either 12h or 24h")
+	}
+
+	for t := range widget.Timezones {
+		if widget.Timezones[t].Timezone == "" {
+			return errors.New("missing timezone value for clock widget")
+		}
+
+		_, err := time.LoadLocation(widget.Timezones[t].Timezone)
+
+		if err != nil {
+			return fmt.Errorf("invalid timezone '%s' for clock widget: %v", widget.Timezones[t].Timezone, err)
+		}
+	}
+
+	widget.cachedHTML = widget.render(widget, assets.ClockTemplate)
+
 	return nil
 }
 
-func (widget *Clock) Update(ctx context.Context) {}
-
 func (widget *Clock) Render() template.HTML {
-	return widget.render(widget, assets.ClockTemplate)
+	return widget.cachedHTML
 }