Proper fix for rating change check (#181)

internal/v1/user/visitor.go

@@ -316,6 +316,21 @@ func isEligibleVisiting(user *models.User) bool {
 		return false
 	}
 
+	// Ignore rating change date if current rating is C3, I1, I3
+	if user.RatingID != 7 && user.RatingID != 8 && user.RatingID != 10 {
+		ratechange, err := vatsim.GetDateOfRatingChange(fmt.Sprint(user.CID))
+		if err != nil {
+			log.Errorf("Error getting date of rating change: %s", err)
+			return false
+		}
+		// Check that ratechange is more than 90 days ago
+		// VATSIM API apparently returns nil if it was a long time ago... so we can assume this check is true
+		// VATUSA only knows about controllers whose rating is changed by VATUSA, so we enforce this by also checking VATSIM
+		if ratechange != nil && ratechange.After(time.Now().AddDate(0, 0, -90)) {
+			return false
+		}
+	}
+
 	// Check VATUSA eligibility
 	eligible, _, err := vatusa.IsVisitorEligible(fmt.Sprint(user.CID))
 	if err != nil {