Create a strategy class to decide which sender id to use

The rules around selecting sender ids can get complicated with some
countries not supporting it and others requiring pre-registration that
may result in having a different sender id for that country than
others. This strategy class handles the logic of dealing with this
expanded configuration and applying the appropriate sender id or none
when it's not appropriate to do so at all.

service/src/main/java/org/whispersystems/textsecuregcm/configuration/TwilioAlphaIdConfiguration.java

@@ -1,31 +0,0 @@
-package org.whispersystems.textsecuregcm.configuration;
-
-import com.google.common.annotations.VisibleForTesting;
-
-import javax.validation.constraints.NotEmpty;
-
-public class TwilioAlphaIdConfiguration {
-  @NotEmpty
-  private String prefix;
-
-  @NotEmpty
-  private String value;
-
-  public String getPrefix() {
-    return prefix;
-  }
-
-  @VisibleForTesting
-  public void setPrefix(String prefix) {
-    this.prefix = prefix;
-  }
-
-  public String getValue() {
-    return value;
-  }
-
-  @VisibleForTesting
-  public void setValue(String value) {
-    this.value = value;
-  }
-}

service/src/main/java/org/whispersystems/textsecuregcm/configuration/TwilioConfiguration.java

@@ -16,34 +16,27 @@
  */
 package org.whispersystems.textsecuregcm.configuration;
 
-import com.fasterxml.jackson.annotation.JsonProperty;
 import com.google.common.annotations.VisibleForTesting;
 
 import javax.validation.Valid;
 import javax.validation.constraints.NotEmpty;
 import javax.validation.constraints.NotNull;
-import java.util.ArrayList;
 import java.util.List;
 
 public class TwilioConfiguration {
 
   @NotEmpty
-  @JsonProperty
   private String accountId;
 
   @NotEmpty
-  @JsonProperty
   private String accountToken;
 
   @NotNull
-  @JsonProperty
   private List<String> numbers;
 
   @NotEmpty
-  @JsonProperty
   private String localDomain;
 
-  @JsonProperty
   private String messagingServicesId;
 
   @NotNull
@@ -56,7 +49,7 @@ public class TwilioConfiguration {
 
   @NotNull
   @Valid
-  private List<TwilioAlphaIdConfiguration> alphaId = new ArrayList<>();
+  private TwilioSenderIdConfiguration senderId = new TwilioSenderIdConfiguration();
 
   public String getAccountId() {
     return accountId;
@@ -121,12 +114,12 @@ public class TwilioConfiguration {
     this.retry = retry;
   }
 
-  public List<TwilioAlphaIdConfiguration> getAlphaId() {
-    return alphaId;
+  public TwilioSenderIdConfiguration getSenderId() {
+    return senderId;
   }
 
   @VisibleForTesting
-  public void setAlphaId(List<TwilioAlphaIdConfiguration> alphaId) {
-    this.alphaId = alphaId;
+  public void setSenderId(TwilioSenderIdConfiguration senderId) {
+    this.senderId = senderId;
   }
 }

service/src/main/java/org/whispersystems/textsecuregcm/configuration/TwilioCountrySenderIdConfiguration.java

@@ -0,0 +1,31 @@
+package org.whispersystems.textsecuregcm.configuration;
+
+import com.google.common.annotations.VisibleForTesting;
+
+import javax.validation.constraints.NotEmpty;
+
+public class TwilioCountrySenderIdConfiguration {
+  @NotEmpty
+  private String countryCode;
+
+  @NotEmpty
+  private String senderId;
+
+  public String getCountryCode() {
+    return countryCode;
+  }
+
+  @VisibleForTesting
+  public void setCountryCode(String countryCode) {
+    this.countryCode = countryCode;
+  }
+
+  public String getSenderId() {
+    return senderId;
+  }
+
+  @VisibleForTesting
+  public void setSenderId(String senderId) {
+    this.senderId = senderId;
+  }
+}

service/src/main/java/org/whispersystems/textsecuregcm/configuration/TwilioSenderIdConfiguration.java

@@ -0,0 +1,51 @@
+package org.whispersystems.textsecuregcm.configuration;
+
+import com.google.common.annotations.VisibleForTesting;
+
+import javax.validation.Valid;
+import javax.validation.constraints.NotEmpty;
+import javax.validation.constraints.NotNull;
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+public class TwilioSenderIdConfiguration {
+  @NotEmpty
+  private String defaultSenderId;
+
+  @NotNull
+  @Valid
+  private List<TwilioCountrySenderIdConfiguration> countrySpecificSenderIds = new ArrayList<>();
+
+  @NotNull
+  @Valid
+  private Set<String> countryCodesWithoutSenderId = new HashSet<>();
+
+  public String getDefaultSenderId() {
+    return defaultSenderId;
+  }
+
+  @VisibleForTesting
+  public void setDefaultSenderId(String defaultSenderId) {
+    this.defaultSenderId = defaultSenderId;
+  }
+
+  public List<TwilioCountrySenderIdConfiguration> getCountrySpecificSenderIds() {
+    return countrySpecificSenderIds;
+  }
+
+  @VisibleForTesting
+  public void setCountrySpecificSenderIds(List<TwilioCountrySenderIdConfiguration> countrySpecificSenderIds) {
+    this.countrySpecificSenderIds = countrySpecificSenderIds;
+  }
+
+  public Set<String> getCountryCodesWithoutSenderId() {
+    return countryCodesWithoutSenderId;
+  }
+
+  @VisibleForTesting
+  public void setCountryCodesWithoutSenderId(Set<String> countryCodesWithoutSenderId) {
+    this.countryCodesWithoutSenderId = countryCodesWithoutSenderId;
+  }
+}