Add billing account map to Registrar entity

A CurrencyUnit-to-BillingAccountEntry map is persisted in the Registrar entity. It provides flexibility for billing systems that assign different account ids for accounts under different currencies of the same registrar.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=151022753

java/google/registry/tools/CreateOrUpdateRegistrarCommand.java

@@ -32,6 +32,7 @@ import google.registry.model.billing.RegistrarBillingUtils;
 import google.registry.model.registrar.Registrar;
 import google.registry.model.registrar.Registrar.BillingMethod;
 import google.registry.model.registrar.RegistrarAddress;
+import google.registry.tools.params.KeyValueMapParameter.CurrencyUnitToStringMap;
 import google.registry.tools.params.OptionalLongParameter;
 import google.registry.tools.params.OptionalPhoneNumberParameter;
 import google.registry.tools.params.OptionalStringParameter;
@@ -169,6 +170,18 @@ abstract class CreateOrUpdateRegistrarCommand extends MutatingCommand {
       validateWith = OptionalLongParameter.class)
   private Optional<Long> billingId;
 
+  @Nullable
+  @Parameter(
+    names = "--billing_account_map",
+    description =
+        "Registrar Billing Account key-value pairs (formatted as key=value[,key=value...]), "
+            + "where key is a currency unit (USD, JPY, etc) and value is the registrar's billing "
+            + "account id for that currency.",
+    converter = CurrencyUnitToStringMap.class,
+    validateWith = CurrencyUnitToStringMap.class
+  )
+  private Map<CurrencyUnit, String> billingAccountMap;
+
   @Nullable
   @Parameter(
       names = "--billing_method",
@@ -334,6 +347,9 @@ abstract class CreateOrUpdateRegistrarCommand extends MutatingCommand {
       if (billingId != null) {
         builder.setBillingIdentifier(billingId.orNull());
       }
+      if (billingAccountMap != null) {
+        builder.setBillingAccountMap(billingAccountMap);
+      }
       if (billingMethod != null) {
         if (oldRegistrar != null && !billingMethod.equals(oldRegistrar.getBillingMethod())) {
           Map<CurrencyUnit, Money> balances = RegistrarBillingUtils.loadBalance(oldRegistrar);

java/google/registry/tools/params/KeyValueMapParameter.java

@@ -18,6 +18,7 @@ import com.google.common.base.Splitter;
 import com.google.common.base.Strings;
 import com.google.common.collect.ImmutableMap;
 import java.util.Map;
+import org.joda.money.CurrencyUnit;
 
 /**
  * Combined converter and validator class for key-value map JCommander argument strings.
@@ -93,4 +94,17 @@ public abstract class KeyValueMapParameter<K, V>
       return Integer.parseInt(value);
     }
   }
+
+  /** Combined converter and validator class for currency unit-to-string Map argument strings. */
+  public static class CurrencyUnitToStringMap extends KeyValueMapParameter<CurrencyUnit, String> {
+    @Override
+    protected CurrencyUnit parseKey(String rawKey) {
+      return CurrencyUnit.of(rawKey);
+    }
+
+    @Override
+    protected String parseValue(String value) {
+      return value;
+    }
+  }
 }