1 files changed, 65 insertions, 0 deletions
diff --git a/internal/router/handlers/api-v1-tz-get.go b/internal/router/handlers/api-v1-tz-get.go
new file mode 100644
index 0000000..8b08113
--- /dev/null
+++ b/internal/router/handlers/api-v1-tz-get.go
@@ -0,0 +1,65 @@
+package handlers
+
+import (
+	"fmt"
+	"log/slog"
+	"time"
+
+	"github.com/SayaAndy/saya-today-web/internal/router"
+	"github.com/gofiber/fiber/v2"
+)
+
+type GetTimezoneHandler struct {
+	router.BasicHandler
+}
+
+func init() {
+	router.Routes = append(router.Routes, &GetTimezoneHandler{})
+}
+
+func (r *GetTimezoneHandler) Filter() (method string, path string) {
+	return "GET", "/api/v1/tz"
+}
+
+func (r *GetTimezoneHandler) IsTemplated() bool {
+	return false
+}
+
+func (r *GetTimezoneHandler) TemplatesToInject() []string {
+	return []string{}
+}
+
+func (r *GetTimezoneHandler) ToCache() router.CacheSetting {
+	return router.Disabled
+}
+
+func (r *GetTimezoneHandler) ToValidateLang() router.LangSetting {
+	return router.NotRequired
+}
+
+func (r *GetTimezoneHandler) Render(c *fiber.Ctx, supplements *router.Supplements, lang string, templateMap fiber.Map) (statusCode int, err error) {
+	timestampString := c.Query("timestamp")
+	tz := c.Query("tz")
+
+	loc, err := time.LoadLocation(tz)
+	if err != nil {
+		loc = time.UTC
+		slog.Warn("unable to parse a client timezone, defaulting to UTC", slog.String("error", err.Error()), slog.String("tz", tz))
+	}
+
+	var format string
+	var timestamp time.Time
+	for _, format = range []string{"2006-01-02 15:04:05 -07:00", time.RFC3339} {
+		if timestamp, err = time.Parse(format, timestampString); err == nil {
+			break
+		}
+	}
+
+	if err != nil {
+		return fiber.StatusBadRequest, fmt.Errorf("invalid timestamp format for '%s'", timestampString)
+	}
+
+	templateMap["Output"] = []byte(timestamp.In(loc).Format("2006-01-02 15:04:05 -07:00"))
+
+	return fiber.StatusOK, nil
+}