#675 Clean up country protection code

- Move validation to validation service

src/main/java/fr/xephi/authme/util/ValidationService.java

@@ -5,7 +5,9 @@ import fr.xephi.authme.output.MessageKey;
 import fr.xephi.authme.permission.PermissionsManager;
 import fr.xephi.authme.permission.PlayerStatePermission;
 import fr.xephi.authme.settings.NewSetting;
+import fr.xephi.authme.settings.domain.Property;
 import fr.xephi.authme.settings.properties.EmailSettings;
+import fr.xephi.authme.settings.properties.ProtectionSettings;
 import fr.xephi.authme.settings.properties.RestrictionSettings;
 import fr.xephi.authme.settings.properties.SecuritySettings;
 import org.bukkit.command.CommandSender;
@@ -52,26 +54,74 @@ public class ValidationService {
         return null;
     }
 
+    /**
+     * Verifies whether the email is valid and admitted for use according to the plugin settings.
+     *
+     * @param email the email to verify
+     * @return true if the email is valid, false otherwise
+     */
     public boolean validateEmail(String email) {
         if (!email.contains("@") || "your@email.com".equalsIgnoreCase(email)) {
             return false;
         }
         final String emailDomain = email.split("@")[1];
-
-        List<String> whitelist = settings.getProperty(EmailSettings.DOMAIN_WHITELIST);
-        if (!CollectionUtils.isEmpty(whitelist)) {
-            return containsIgnoreCase(whitelist, emailDomain);
-        }
-
-        List<String> blacklist = settings.getProperty(EmailSettings.DOMAIN_BLACKLIST);
-        return CollectionUtils.isEmpty(blacklist) || !containsIgnoreCase(blacklist, emailDomain);
+        return validateWhitelistAndBlacklist(
+            emailDomain, EmailSettings.DOMAIN_WHITELIST, EmailSettings.DOMAIN_BLACKLIST);
     }
 
+    /**
+     * Queries the database whether the email is still free for registration, i.e. whether the given
+     * command sender may use the email to register a new account (as defined by settings and permissions).
+     *
+     * @param email the email to verify
+     * @param sender the command sender
+     * @return true if the email may be used, false otherwise (registration threshold has been exceeded)
+     */
     public boolean isEmailFreeForRegistration(String email, CommandSender sender) {
         return permissionsManager.hasPermission(sender, PlayerStatePermission.ALLOW_MULTIPLE_ACCOUNTS)
             || dataSource.countAuthsByEmail(email) < settings.getProperty(EmailSettings.MAX_REG_PER_EMAIL);
     }
 
+    /**
+     * Checks whether the player's country is allowed to join the server, based on the given IP address
+     * and the configured country whitelist or blacklist.
+     *
+     * @param hostAddress the IP address to verify
+     * @return true if the IP address' country is allowed, false otherwise
+     */
+    public boolean isCountryAdmitted(String hostAddress) {
+        // Check if we have restrictions on country, if not return true and avoid the country lookup
+        if (settings.getProperty(ProtectionSettings.COUNTRIES_WHITELIST).isEmpty()
+            && settings.getProperty(ProtectionSettings.COUNTRIES_BLACKLIST).isEmpty()) {
+            return true;
+        }
+
+        String countryCode = GeoLiteAPI.getCountryCode(hostAddress);
+        return validateWhitelistAndBlacklist(countryCode,
+            ProtectionSettings.COUNTRIES_WHITELIST,
+            ProtectionSettings.COUNTRIES_BLACKLIST);
+    }
+
+    /**
+     * Verifies whether the given value is allowed according to the given whitelist and blacklist settings.
+     * Whitelist has precedence over blacklist: if a whitelist is set, the value is rejected if not present
+     * in the whitelist.
+     *
+     * @param value the value to verify
+     * @param whitelist the whitelist property
+     * @param blacklist the blacklist property
+     * @return true if the value is admitted by the lists, false otherwise
+     */
+    private boolean validateWhitelistAndBlacklist(String value, Property<List<String>> whitelist,
+                                                  Property<List<String>> blacklist) {
+        List<String> whitelistValue = settings.getProperty(whitelist);
+        if (!CollectionUtils.isEmpty(whitelistValue)) {
+            return containsIgnoreCase(whitelistValue, value);
+        }
+        List<String> blacklistValue = settings.getProperty(blacklist);
+        return CollectionUtils.isEmpty(blacklistValue) || !containsIgnoreCase(blacklistValue, value);
+    }
+
     private static boolean containsIgnoreCase(Collection<String> coll, String needle) {
         for (String entry : coll) {
             if (entry.equalsIgnoreCase(needle)) {