Add example regex address verification and test

gui/src/main/java/io/bitsquare/gui/util/validation/AltCoinAddressValidator.java

@@ -18,7 +18,11 @@
 package io.bitsquare.gui.util.validation;
 
 
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 public final class AltCoinAddressValidator extends InputValidator {
+    private static final Logger log = LoggerFactory.getLogger(AltCoinAddressValidator.class);
 
     private String currencyCode;
 
@@ -32,21 +36,49 @@ public final class AltCoinAddressValidator extends InputValidator {
 
     @Override
     public ValidationResult validate(String input) {
-        if (currencyCode != null) {
+        ValidationResult validationResult = super.validate(input);
+        if (!validationResult.isValid || currencyCode == null) {
+            return validationResult;
+        } else {
+
+            // Validation: 
+            // 1: With a regex checking the correct structure of an address 
+            // 2: If the address contains a checksum, verify the checksum
+
+            ValidationResult wrongChecksum = new ValidationResult(false, "Address validation failed because checksum was not correct.");
+            ValidationResult wrongStructure = new ValidationResult(false, "Address validation failed because it does not match the structure of a " + currencyCode + " address.");
+
             switch (currencyCode) {
+                // Example for BTC, though for BTC we use the BitcoinJ library address check
+                case "BTC":
+                    log.error("" + input.length());
+                    // taken form: https://stackoverflow.com/questions/21683680/regex-to-match-bitcoin-addresses
+                    if (input.matches("^[13][a-km-zA-HJ-NP-Z1-9]{25,34}$")) {
+                        if (verifyChecksum(input))
+                            return new ValidationResult(true);
+                        else
+                            return wrongStructure;
+                    } else {
+                        return wrongChecksum;
+                    }
                 case "ZEC":
-                    if (input != null && input.startsWith("t"))
-                        return super.validate(input);
+                    // We only support t addresses (transparent transactions)
+                    if (input.startsWith("t"))
+                        return validationResult;
                     else
                         return new ValidationResult(false, "ZEC address need to start with t. Addresses starting with z are not supported.");
                 default:
-                    return super.validate(input);
+                    log.debug("Validation for AltCoinAddress not implemented yet. currencyCode:" + currencyCode);
+                    return validationResult;
             }
-        } else {
-            return super.validate(input);
         }
     }
 
+    private boolean verifyChecksum(String input) {
+        // TODO
+        return true;
+    }
+
 
     ///////////////////////////////////////////////////////////////////////////////////////////
     // Private methods

gui/src/test/java/io/bitsquare/gui/util/validation/AltCoinAddressValidatorTest.java

@@ -0,0 +1,42 @@
+/*
+ * This file is part of Bitsquare.
+ *
+ * Bitsquare is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or (at
+ * your option) any later version.
+ *
+ * Bitsquare is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General Public
+ * License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with Bitsquare. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package io.bitsquare.gui.util.validation;
+
+import org.junit.Test;
+
+import static junit.framework.TestCase.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+public class AltCoinAddressValidatorTest {
+
+    @Test
+    public void testBTC() {
+        AltCoinAddressValidator validator = new AltCoinAddressValidator();
+        validator.setCurrencyCode("BTC");
+
+        assertTrue(validator.validate("17VZNX1SN5NtKa8UQFxwQbFeFc3iqRYhem").isValid);
+        assertTrue(validator.validate("3EktnHQD7RiAE6uzMj2ZifT9YgRrkSgzQX").isValid);
+        assertTrue(validator.validate("1111111111111111111114oLvT2").isValid);
+        assertTrue(validator.validate("1BitcoinEaterAddressDontSendf59kuE").isValid);
+
+        assertFalse(validator.validate("17VZNX1SN5NtKa8UQFxwQbFeFc3iqRYhemqq").isValid);
+        assertFalse(validator.validate("17VZNX1SN5NtKa8UQFxwQbFeFc3iqRYheO").isValid);
+        assertFalse(validator.validate("17VZNX1SN5NtKa8UQFxwQbFeFc3iqRYhek#").isValid);
+    }
+
+}