TextClassifier updates

- Increase the size of the text sent as context to the classifier
- Pass regex match hints to the classifer

Test: Build still works. Regex hints logged correctly. The hints won't
matter until we've actually passed in this values to native code. Native
library test will be written and I've got a tracker bug to write more robust Java tests.

Bug: 35416389
Bug: 36584397

Change-Id: I29e56189b388b36dc0cc7a8bb13ef237ff55be7b

core/java/android/view/textclassifier/SmartSelection.java

@@ -26,6 +26,11 @@ final class SmartSelection {
         System.loadLibrary("textclassifier");
     }
 
+    /** Hints the classifier that this may be a url. */
+    static final int HINT_FLAG_URL = 0x01;
+    /** Hints the classifier that this may be an email. */
+    static final int HINT_FLAG_EMAIL = 0x02;
+
     private final long mCtx;
 
     /**
@@ -59,7 +64,7 @@ final class SmartSelection {
      * scores for different collections.
      */
     public ClassificationResult[] classifyText(
-            String context, int selectionBegin, int selectionEnd) {
+            String context, int selectionBegin, int selectionEnd, int hintFlags) {
         return nativeClassifyText(mCtx, context, selectionBegin, selectionEnd);
     }
 

core/java/android/view/textclassifier/TextClassifierImpl.java

@@ -35,6 +35,7 @@ import android.text.method.WordIterator;
 import android.text.style.ClickableSpan;
 import android.text.util.Linkify;
 import android.util.Log;
+import android.util.Patterns;
 import android.view.View;
 
 import com.android.internal.util.Preconditions;
@@ -88,7 +89,9 @@ final class TextClassifierImpl implements TextClassifier {
                 if (start >= 0 && end <= string.length() && start <= end) {
                     final TextSelection.Builder tsBuilder = new TextSelection.Builder(start, end);
                     final SmartSelection.ClassificationResult[] results =
-                            getSmartSelection().classifyText(string, start, end);
+                            getSmartSelection().classifyText(
+                                    string, start, end,
+                                    getHintFlags(string, start, end));
                     final int size = results.length;
                     for (int i = 0; i < size; i++) {
                         tsBuilder.setEntityType(results[i].mCollection, results[i].mScore);
@@ -116,12 +119,14 @@ final class TextClassifierImpl implements TextClassifier {
         validateInput(text, startIndex, endIndex);
         try {
             if (text.length() > 0) {
-                final CharSequence classified = text.subSequence(startIndex, endIndex);
+                final String string = text.toString();
                 SmartSelection.ClassificationResult[] results = getSmartSelection()
-                        .classifyText(text.toString(), startIndex, endIndex);
+                        .classifyText(string, startIndex, endIndex,
+                                getHintFlags(string, startIndex, endIndex));
                 if (results.length > 0) {
                     final TextClassificationResult classificationResult =
-                            createClassificationResult(results, classified);
+                            createClassificationResult(
+                                    results, string.subSequence(startIndex, endIndex));
                     // TODO: Added this log for debug only. Remove before release.
                     Log.d(LOG_TAG, String.format(
                             "Classification type: %s", classificationResult));
@@ -208,6 +213,24 @@ final class TextClassifierImpl implements TextClassifier {
         return builder.build();
     }
 
+    private static int getHintFlags(CharSequence text, int start, int end) {
+        int flag = 0;
+        final CharSequence subText = text.subSequence(start, end);
+        if (Patterns.AUTOLINK_EMAIL_ADDRESS.matcher(subText).matches()) {
+            flag |= SmartSelection.HINT_FLAG_EMAIL;
+        }
+        if (Patterns.AUTOLINK_WEB_URL.matcher(subText).matches()
+                && Linkify.sUrlMatchFilter.acceptMatch(text, start, end)) {
+            flag |= SmartSelection.HINT_FLAG_URL;
+        }
+        // TODO: Added this log for debug only. Remove before release.
+        Log.d(LOG_TAG, String.format("Email hint: %b",
+                (flag & SmartSelection.HINT_FLAG_EMAIL) != 0));
+        Log.d(LOG_TAG, String.format("Url hint: %b",
+                (flag & SmartSelection.HINT_FLAG_URL) != 0));
+        return flag;
+    }
+
     private static String getHighestScoringType(SmartSelection.ClassificationResult[] types) {
         if (types.length < 1) {
             return "";
@@ -262,7 +285,9 @@ final class TextClassifierImpl implements TextClassifier {
                 if (selectionStart >= 0 && selectionEnd <= text.length()
                         && selectionStart <= selectionEnd) {
                     final SmartSelection.ClassificationResult[] results =
-                            smartSelection.classifyText(text, selectionStart, selectionEnd);
+                            smartSelection.classifyText(
+                                    text, selectionStart, selectionEnd,
+                                    getHintFlags(text, selectionStart, selectionEnd));
                     if (results.length > 0) {
                         final String type = getHighestScoringType(results);
                         if (matches(type, linkMask)) {

core/java/android/widget/SelectionActionModeHelper.java

@@ -289,7 +289,7 @@ final class SelectionActionModeHelper {
      */
     private static final class TextClassificationHelper {
 
-        private static final int TRIM_DELTA = 50;  // characters
+        private static final int TRIM_DELTA = 120;  // characters
 
         private TextClassifier mTextClassifier;