add TimeZone API

directions.go

@@ -27,6 +27,7 @@ const (
 	StatusInvalidRequest       = "INVALID_REQUEST"
 	StatusRequestDenied        = "REQUEST_DENIED"
 	StatusUnknownError         = "UNKNOWN_ERROR"
+	StatusOverQueryLimit       = "OVER_QUERY_LIMIT"
 )
 
 // TODO: via_waypoint not documented

maps_test.go

@@ -90,3 +90,15 @@ func TestStreetView(t *testing.T) {
 		t.Errorf("unexpected error: %v", err)
 	}
 }
+
+func TestTimeZone(t *testing.T) {
+	c := NewClient("")
+	ll := LatLng{40.7142700, -74.0059700}
+	tm := time.Now()
+	t.Logf("%s", baseURL+timezone(ll, tm, nil))
+	r, err := c.TimeZone(ll, tm, nil)
+	if err != nil {
+		t.Errorf("unexpected error: %v", err)
+	}
+	t.Logf("%v", r)
+}

timezone.go

@@ -0,0 +1,53 @@
+package maps
+
+import (
+	"fmt"
+	"net/url"
+	"time"
+)
+
+func (c Client) TimeZone(ll LatLng, t time.Time, opts *TimeZoneOpts) (*TimeZoneResponse, error) {
+	var r TimeZoneResponse
+	if err := c.doDecode(baseURL+timezone(ll, t, opts), &r); err != nil {
+		return nil, err
+	}
+	return &r, nil
+}
+
+func timezone(ll LatLng, t time.Time, opts *TimeZoneOpts) string {
+	p := url.Values{}
+	p.Set("location", ll.String())
+	p.Set("timestamp", fmt.Sprintf("%d", t.Unix()))
+	opts.update(p)
+	return "timezone/json?" + p.Encode()
+}
+
+type TimeZoneOpts struct {
+	Language string
+}
+
+func (t *TimeZoneOpts) update(p url.Values) {
+	if t == nil {
+		return
+	}
+	if t.Language != "" {
+		p.Set("language", t.Language)
+	}
+}
+
+type TimeZoneResponse struct {
+	Status       string `json:"status"`
+	ErrorMessage string `json:"error_message"`
+	DSTOffset    int64  `json:"dstOffset"` // secs offset for DST
+	RawOffset    int64  `json:"rawOffset"`
+	TimeZoneID   string `json:"timeZoneId"`
+	TimeZoneName string `json:"timeZoneName"`
+}
+
+func (r TimeZoneResponse) DSTOffsetDuration() time.Duration {
+	return time.Duration(r.DSTOffset) * time.Second
+}
+
+func (r TimeZoneResponse) RawOffsetDuration() time.Duration {
+	return time.Duration(r.RawOffset) * time.Second
+}