package middleware

import (
	"context"
	"net/http"

	"git.toowon.com/jimmy/go-common/requestctx"
	"git.toowon.com/jimmy/go-common/tools"
)

// TimezoneHeaderName 时区请求头名称
const TimezoneHeaderName = "X-Timezone"

// GetTimezoneFromContext 从 context 中获取时区
func GetTimezoneFromContext(ctx context.Context) string {
	return requestctx.Timezone(ctx)
}

// Timezone 时区处理中间件
func Timezone(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		timezone := r.Header.Get(TimezoneHeaderName)
		if timezone == "" {
			timezone = requestctx.DefaultTimezone
		}
		if _, err := tools.GetLocation(timezone); err != nil {
			timezone = requestctx.DefaultTimezone
		}
		ctx := requestctx.WithTimezone(r.Context(), timezone)
		next.ServeHTTP(w, r.WithContext(ctx))
	})
}

// TimezoneWithDefault 时区处理中间件（可自定义默认时区）
func TimezoneWithDefault(defaultTimezone string) func(http.Handler) http.Handler {
	if _, err := tools.GetLocation(defaultTimezone); err != nil {
		defaultTimezone = requestctx.DefaultTimezone
	}
	return func(next http.Handler) http.Handler {
		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
			timezone := r.Header.Get(TimezoneHeaderName)
			if timezone == "" {
				timezone = defaultTimezone
			}
			if _, err := tools.GetLocation(timezone); err != nil {
				timezone = defaultTimezone
			}
			ctx := requestctx.WithTimezone(r.Context(), timezone)
			next.ServeHTTP(w, r.WithContext(ctx))
		})
	}
}