Add the assisted dialing logic module.

This implements the core assisted dialing logic specified in
go/assisted-dialing-dd-v1

Bug: 36414469,63995261
Test: new unit tests
PiperOrigin-RevId: 170232634
Change-Id: I3b668c3a0e9fb5398eca4614548c8141b200e70e

1 files changed, 93 insertions, 0 deletions

diff --git a/java/com/android/dialer/assisteddialing/NumberTransformer.java b/java/com/android/dialer/assisteddialing/NumberTransformer.java
new file mode 100644
index 000000000..f01d1a08f
--- /dev/null
+++ b/java/com/android/dialer/assisteddialing/NumberTransformer.java
@@ -0,0 +1,93 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.dialer.assisteddialing;
+
+import android.annotation.TargetApi;
+import android.os.Build.VERSION_CODES;
+import android.support.annotation.NonNull;
+import android.text.TextUtils;
+import com.android.dialer.common.LogUtil;
+import com.google.i18n.phonenumbers.NumberParseException;
+import com.google.i18n.phonenumbers.PhoneNumberUtil;
+import com.google.i18n.phonenumbers.Phonenumber.PhoneNumber;
+import java.util.Optional;
+
+/** Responsible for transforming numbers to make them dialable and valid when roaming. */
+final class NumberTransformer {
+
+  private final PhoneNumberUtil phoneNumberUtil = PhoneNumberUtil.getInstance();
+  private final Constraints constraints;
+
+  public NumberTransformer(Constraints constraints) {
+    this.constraints = constraints;
+  }
+
+  /**
+   * Returns a boolean for callers to quickly determine whether or not the AssistedDialingMediator
+   * thinks an attempt at assisted dialing is likely to succeed.
+   */
+  public boolean canDoAssistedDialingTransformation(
+      @NonNull String numberToCheck,
+      @NonNull String userHomeCountryCode,
+      @NonNull String userRoamingCountryCode) {
+    return constraints.meetsPreconditions(
+        numberToCheck, userHomeCountryCode, userRoamingCountryCode);
+  }
+
+  /**
+   * A method to do assisted dialing transformations.
+   *
+   * <p>The library will do its best to attempt a transformation, but, if for any reason the
+   * transformation fails, we return an empty optional. The operation can be considered a success
+   * when the Optional we return has a value set.
+   */
+  @SuppressWarnings("AndroidApiChecker") // Use of optional
+  @TargetApi(VERSION_CODES.N)
+  public Optional<String> doAssistedDialingTransformation(
+      String numbertoTransform, String userHomeCountryCode, String userRoamingCountryCode) {
+
+    if (!constraints.meetsPreconditions(
+        numbertoTransform, userHomeCountryCode, userRoamingCountryCode)) {
+      LogUtil.i(
+          "NumberTransformer.doAssistedDialingTransformation",
+          "assisted dialing failed preconditions");
+      return Optional.empty();
+    }
+
+    PhoneNumber phoneNumber;
+    try {
+      phoneNumber = phoneNumberUtil.parse(numbertoTransform, userHomeCountryCode);
+    } catch (NumberParseException e) {
+      LogUtil.i("NumberTransformer.doAssistedDialingTransformation", "number failed to parse");
+      return Optional.empty();
+    }
+
+    String transformedNumber =
+        phoneNumberUtil.formatNumberForMobileDialing(phoneNumber, userRoamingCountryCode, true);
+
+    // formatNumberForMobileDialing may return an empty String.
+    if (TextUtils.isEmpty(transformedNumber)) {
+      LogUtil.i(
+          "NumberTransformer.doAssistedDialingTransformation",
+          "formatNumberForMobileDialing returned an empty string");
+      return Optional.empty();
+    }
+
+    // TODO Verify the transformed number is still valid?
+    return Optional.of(transformedNumber);
+  }
+}