Restart suggestions when the cursor moves.

This uses the old suggestions. It does not try to recompute
new suggestions if there are no old suggestions yet: this is
coming in a later change.
If there are no suggestions, this shows the word itself
as a suggestion.

Bug: 8084810
Change-Id: I4c2e25df0ff3673be1825f57a0c19a9d23d47a48

7 files changed, 103 insertions, 15 deletions

diff --git a/java/src/com/android/inputmethod/latin/Dictionary.java b/java/src/com/android/inputmethod/latin/Dictionary.java
index ff3d83fad..9691fa231 100644
--- a/java/src/com/android/inputmethod/latin/Dictionary.java
+++ b/java/src/com/android/inputmethod/latin/Dictionary.java
@@ -37,6 +37,8 @@ public abstract class Dictionary {
     public static final String TYPE_USER = "user";
     // User history dictionary internal to LatinIME.
     public static final String TYPE_USER_HISTORY = "history";
+    // Spawned by resuming suggestions. Comes from a span that was in the TextView.
+    public static final String TYPE_RESUMED = "resumed";
     protected final String mDictType;
 
     public Dictionary(final String dictType) {
diff --git a/java/src/com/android/inputmethod/latin/LatinIME.java b/java/src/com/android/inputmethod/latin/LatinIME.java
index 0f1f14957..e644f38b4 100644
--- a/java/src/com/android/inputmethod/latin/LatinIME.java
+++ b/java/src/com/android/inputmethod/latin/LatinIME.java
@@ -44,7 +44,9 @@ import android.os.Message;
 import android.os.SystemClock;
 import android.preference.PreferenceManager;
 import android.text.InputType;
+import android.text.SpannableString;
 import android.text.TextUtils;
+import android.text.style.SuggestionSpan;
 import android.util.Log;
 import android.util.PrintWriterPrinter;
 import android.util.Printer;
@@ -72,6 +74,7 @@ import com.android.inputmethod.keyboard.KeyboardActionListener;
 import com.android.inputmethod.keyboard.KeyboardId;
 import com.android.inputmethod.keyboard.KeyboardSwitcher;
 import com.android.inputmethod.keyboard.MainKeyboardView;
+import com.android.inputmethod.latin.RichInputConnection.Range;
 import com.android.inputmethod.latin.SuggestedWords.SuggestedWordInfo;
 import com.android.inputmethod.latin.Utils.Stats;
 import com.android.inputmethod.latin.define.ProductionFlag;
@@ -197,6 +200,7 @@ public final class LatinIME extends InputMethodService implements KeyboardAction
         private static final int MSG_PENDING_IMS_CALLBACK = 1;
         private static final int MSG_UPDATE_SUGGESTION_STRIP = 2;
         private static final int MSG_SHOW_GESTURE_PREVIEW_AND_SUGGESTION_STRIP = 3;
+        private static final int MSG_RESUME_SUGGESTIONS = 4;
 
         private static final int ARG1_DISMISS_GESTURE_FLOATING_PREVIEW_TEXT = 1;
 
@@ -234,6 +238,9 @@ public final class LatinIME extends InputMethodService implements KeyboardAction
                 latinIme.showGesturePreviewAndSuggestionStrip((SuggestedWords)msg.obj,
                         msg.arg1 == ARG1_DISMISS_GESTURE_FLOATING_PREVIEW_TEXT);
                 break;
+            case MSG_RESUME_SUGGESTIONS:
+                latinIme.restartSuggestionsOnWordTouchedByCursor();
+                break;
             }
         }
 
@@ -241,6 +248,10 @@ public final class LatinIME extends InputMethodService implements KeyboardAction
             sendMessageDelayed(obtainMessage(MSG_UPDATE_SUGGESTION_STRIP), mDelayUpdateSuggestions);
         }
 
+        public void postResumeSuggestions() {
+            sendMessageDelayed(obtainMessage(MSG_RESUME_SUGGESTIONS), mDelayUpdateSuggestions);
+        }
+
         public void cancelUpdateSuggestionStrip() {
             removeMessages(MSG_UPDATE_SUGGESTION_STRIP);
         }
@@ -910,13 +921,12 @@ public final class LatinIME extends InputMethodService implements KeyboardAction
                 resetEntireInputState(newSelStart);
             }
 
+            // We moved the cursor. If we are touching a word, we need to resume suggestion.
+            mHandler.postResumeSuggestions();
+
             mKeyboardSwitcher.updateShiftState();
         }
         mExpectingUpdateSelection = false;
-        // TODO: Decide to call restartSuggestionsOnWordBeforeCursorIfAtEndOfWord() or not
-        // here. It would probably be too expensive to call directly here but we may want to post a
-        // message to delay it. The point would be to unify behavior between backspace to the
-        // end of a word and manually put the pointer at the end of the word.
 
         // Make a note of the cursor position
         mLastSelectionStart = newSelStart;
@@ -1727,6 +1737,9 @@ public final class LatinIME extends InputMethodService implements KeyboardAction
         // during key repeat.
         mHandler.postUpdateShiftState();
 
+        if (mWordComposer.isComposingWord() && !mWordComposer.isCursorAtEndOfComposingWord()) {
+            resetEntireInputState(mLastSelectionStart);
+        }
         if (mWordComposer.isComposingWord()) {
             final int length = mWordComposer.size();
             if (length > 0) {
@@ -1858,6 +1871,10 @@ public final class LatinIME extends InputMethodService implements KeyboardAction
             promotePhantomSpace();
         }
 
+        if (mWordComposer.isComposingWord() && !mWordComposer.isCursorAtEndOfComposingWord()) {
+            resetEntireInputState(mLastSelectionStart);
+            isComposingWord = false;
+        }
         // NOTE: isCursorTouchingWord() is a blocking IPC call, so it often takes several
         // dozen milliseconds. Avoid calling it as much as possible, since we are on the UI
         // thread here.
@@ -2331,6 +2348,48 @@ public final class LatinIME extends InputMethodService implements KeyboardAction
     }
 
     /**
+     * Check if the cursor is touching a word. If so, restart suggestions on this word, else
+     * do nothing.
+     */
+    private void restartSuggestionsOnWordTouchedByCursor() {
+        // If the cursor is not touching a word, or if there is a selection, return right away.
+        if (mLastSelectionStart != mLastSelectionEnd) return;
+        if (!mConnection.isCursorTouchingWord(mSettings.getCurrent())) return;
+        final Range range = mConnection.getWordRangeAtCursor(mSettings.getWordSeparators(),
+                0 /* additionalPrecedingWordsCount */);
+        final ArrayList<SuggestedWordInfo> suggestions = CollectionUtils.newArrayList();
+        if (range.mWord instanceof SpannableString) {
+            final SpannableString spannableString = (SpannableString)range.mWord;
+            final String typedWord = spannableString.toString();
+            int i = 0;
+            for (Object object : spannableString.getSpans(0, spannableString.length(),
+                    SuggestionSpan.class)) {
+                SuggestionSpan span = (SuggestionSpan)object;
+                for (String s : span.getSuggestions()) {
+                    ++i;
+                    if (!TextUtils.equals(s, typedWord)) {
+                        suggestions.add(new SuggestedWordInfo(s,
+                                SuggestionStripView.MAX_SUGGESTIONS - i,
+                                SuggestedWordInfo.KIND_RESUMED, Dictionary.TYPE_RESUMED));
+                    }
+                }
+            }
+        }
+        mWordComposer.setComposingWord(range.mWord, mKeyboardSwitcher.getKeyboard());
+        mWordComposer.setCursorPositionWithinWord(range.mCharsBefore);
+        mConnection.setComposingRegion(mLastSelectionStart - range.mCharsBefore,
+                mLastSelectionEnd + range.mCharsAfter);
+        if (suggestions.isEmpty()) {
+            suggestions.add(new SuggestedWordInfo(range.mWord.toString(), 1,
+                    SuggestedWordInfo.KIND_TYPED, Dictionary.TYPE_RESUMED));
+        }
+        showSuggestionStrip(new SuggestedWords(suggestions,
+                true /* typedWordValid */, false /* willAutoCorrect */,
+                false /* isPunctuationSuggestions */, false /* isObsoleteSuggestions */,
+                false /* isPrediction */), range.mWord.toString());
+    }
+
+    /**
      * Check if the cursor is actually at the end of a word. If so, restart suggestions on this
      * word, else do nothing.
      */
@@ -2338,17 +2397,18 @@ public final class LatinIME extends InputMethodService implements KeyboardAction
         final CharSequence word =
                 mConnection.getWordBeforeCursorIfAtEndOfWord(mSettings.getCurrent());
         if (null != word) {
-            restartSuggestionsOnWordBeforeCursor(word);
+            final String wordString = word.toString();
+            restartSuggestionsOnWordBeforeCursor(wordString);
             // TODO: Handle the case where the user manually moves the cursor and then backs up over
             // a separator.  In that case, the current log unit should not be uncommitted.
             if (ProductionFlag.USES_DEVELOPMENT_ONLY_DIAGNOSTICS) {
-                ResearchLogger.getInstance().uncommitCurrentLogUnit(word.toString(),
+                ResearchLogger.getInstance().uncommitCurrentLogUnit(wordString,
                         true /* dumpCurrentLogUnit */);
             }
         }
     }
 
-    private void restartSuggestionsOnWordBeforeCursor(final CharSequence word) {
+    private void restartSuggestionsOnWordBeforeCursor(final String word) {
         mWordComposer.setComposingWord(word, mKeyboardSwitcher.getKeyboard());
         final int length = word.length();
         mConnection.deleteSurroundingText(length, 0);
diff --git a/java/src/com/android/inputmethod/latin/RichInputConnection.java b/java/src/com/android/inputmethod/latin/RichInputConnection.java
index 16744d1f0..4699d4c0c 100644
--- a/java/src/com/android/inputmethod/latin/RichInputConnection.java
+++ b/java/src/com/android/inputmethod/latin/RichInputConnection.java
@@ -17,7 +17,9 @@
 package com.android.inputmethod.latin;
 
 import android.inputmethodservice.InputMethodService;
+import android.text.SpannableString;
 import android.text.TextUtils;
+import android.text.style.SuggestionSpan;
 import android.util.Log;
 import android.view.KeyEvent;
 import android.view.inputmethod.CompletionInfo;
@@ -442,9 +444,9 @@ public final class RichInputConnection {
         public final int mCharsAfter;
 
         /** The actual characters that make up a word */
-        public final String mWord;
+        public final CharSequence mWord;
 
-        public Range(int charsBefore, int charsAfter, String word) {
+        public Range(int charsBefore, int charsAfter, CharSequence word) {
             if (charsBefore < 0 || charsAfter < 0) {
                 throw new IndexOutOfBoundsException();
             }
@@ -498,7 +500,7 @@ public final class RichInputConnection {
      *   separator. For example, if the field contains "he|llo world", where |
      *   represents the cursor, then "hello " will be returned.
      */
-    public String getWordAtCursor(String separators) {
+    public CharSequence getWordAtCursor(String separators) {
         // getWordRangeAtCursor returns null if the connection is null
         Range r = getWordRangeAtCursor(separators, 0);
         return (r == null) ? null : r.mWord;
@@ -517,8 +519,10 @@ public final class RichInputConnection {
         if (mIC == null || sep == null) {
             return null;
         }
-        final CharSequence before = mIC.getTextBeforeCursor(1000, 0);
-        final CharSequence after = mIC.getTextAfterCursor(1000, 0);
+        final CharSequence before = mIC.getTextBeforeCursor(1000,
+                InputConnection.GET_TEXT_WITH_STYLES);
+        final CharSequence after = mIC.getTextAfterCursor(1000,
+                InputConnection.GET_TEXT_WITH_STYLES);
         if (before == null || after == null) {
             return null;
         }
@@ -560,8 +564,9 @@ public final class RichInputConnection {
             }
         }
 
-        final String word = before.toString().substring(startIndexInBefore, before.length())
-                + after.toString().substring(0, endIndexInAfter);
+        final SpannableString word = new SpannableString(TextUtils.concat(
+                before.subSequence(startIndexInBefore, before.length()),
+                after.subSequence(0, endIndexInAfter)));
         return new Range(before.length() - startIndexInBefore, endIndexInAfter, word);
     }
 
diff --git a/java/src/com/android/inputmethod/latin/Settings.java b/java/src/com/android/inputmethod/latin/Settings.java
index 8fbe843cf..318d2b23f 100644
--- a/java/src/com/android/inputmethod/latin/Settings.java
+++ b/java/src/com/android/inputmethod/latin/Settings.java
@@ -134,6 +134,10 @@ public final class Settings implements SharedPreferences.OnSharedPreferenceChang
         return mSettingsValues.mIsInternal;
     }
 
+    public String getWordSeparators() {
+        return mSettingsValues.mWordSeparators;
+    }
+
     // Accessed from the settings interface, hence public
     public static boolean readKeypressSoundEnabled(final SharedPreferences prefs,
             final Resources res) {
diff --git a/java/src/com/android/inputmethod/latin/SuggestedWords.java b/java/src/com/android/inputmethod/latin/SuggestedWords.java
index 3d6fe2d22..158cc1155 100644
--- a/java/src/com/android/inputmethod/latin/SuggestedWords.java
+++ b/java/src/com/android/inputmethod/latin/SuggestedWords.java
@@ -131,6 +131,7 @@ public final class SuggestedWords {
         public static final int KIND_APP_DEFINED = 6; // Suggested by the application
         public static final int KIND_SHORTCUT = 7; // A shortcut
         public static final int KIND_PREDICTION = 8; // A prediction (== a suggestion with no input)
+        public static final int KIND_RESUMED = 9; // A resumed suggestion (comes from a span)
         public final String mWord;
         public final int mScore;
         public final int mKind; // one of the KIND_* constants above
diff --git a/java/src/com/android/inputmethod/latin/WordComposer.java b/java/src/com/android/inputmethod/latin/WordComposer.java
index f7cb4346a..1af12428d 100644
--- a/java/src/com/android/inputmethod/latin/WordComposer.java
+++ b/java/src/com/android/inputmethod/latin/WordComposer.java
@@ -49,6 +49,7 @@ public final class WordComposer {
     private int mCapitalizedMode;
     private int mTrailingSingleQuotesCount;
     private int mCodePointSize;
+    private int mCursorPositionWithinWord;
 
     /**
      * Whether the user chose to capitalize the first char of the word.
@@ -62,6 +63,7 @@ public final class WordComposer {
         mTrailingSingleQuotesCount = 0;
         mIsResumed = false;
         mIsBatchMode = false;
+        mCursorPositionWithinWord = 0;
         refreshSize();
     }
 
@@ -76,6 +78,7 @@ public final class WordComposer {
         mTrailingSingleQuotesCount = source.mTrailingSingleQuotesCount;
         mIsResumed = source.mIsResumed;
         mIsBatchMode = source.mIsBatchMode;
+        mCursorPositionWithinWord = source.mCursorPositionWithinWord;
         refreshSize();
     }
 
@@ -91,6 +94,7 @@ public final class WordComposer {
         mTrailingSingleQuotesCount = 0;
         mIsResumed = false;
         mIsBatchMode = false;
+        mCursorPositionWithinWord = 0;
         refreshSize();
     }
 
@@ -135,6 +139,7 @@ public final class WordComposer {
         final int newIndex = size();
         mTypedWord.appendCodePoint(primaryCode);
         refreshSize();
+        mCursorPositionWithinWord = mCodePointSize;
         if (newIndex < MAX_WORD_LENGTH) {
             mPrimaryKeyCodes[newIndex] = primaryCode >= Constants.CODE_SPACE
                     ? Character.toLowerCase(primaryCode) : primaryCode;
@@ -158,6 +163,14 @@ public final class WordComposer {
         mAutoCorrection = null;
     }
 
+    public void setCursorPositionWithinWord(final int posWithinWord) {
+        mCursorPositionWithinWord = posWithinWord;
+    }
+
+    public boolean isCursorAtEndOfComposingWord() {
+        return mCursorPositionWithinWord == mCodePointSize;
+    }
+
     public void setBatchInputPointers(final InputPointers batchPointers) {
         mInputPointers.set(batchPointers);
         mIsBatchMode = true;
@@ -242,6 +255,7 @@ public final class WordComposer {
                 ++mTrailingSingleQuotesCount;
             }
         }
+        mCursorPositionWithinWord = mCodePointSize;
         mAutoCorrection = null;
     }
 
@@ -368,6 +382,7 @@ public final class WordComposer {
         mCapitalizedMode = CAPS_MODE_OFF;
         refreshSize();
         mAutoCorrection = null;
+        mCursorPositionWithinWord = 0;
         mIsResumed = false;
         return lastComposedWord;
     }
@@ -380,6 +395,7 @@ public final class WordComposer {
         refreshSize();
         mCapitalizedMode = lastComposedWord.mCapitalizedMode;
         mAutoCorrection = null; // This will be filled by the next call to updateSuggestion.
+        mCursorPositionWithinWord = mCodePointSize;
         mIsResumed = true;
     }
 
diff --git a/java/src/com/android/inputmethod/research/ResearchLogger.java b/java/src/com/android/inputmethod/research/ResearchLogger.java
index c05de0992..320db8123 100644
--- a/java/src/com/android/inputmethod/research/ResearchLogger.java
+++ b/java/src/com/android/inputmethod/research/ResearchLogger.java
@@ -1283,7 +1283,7 @@ public class ResearchLogger implements SharedPreferences.OnSharedPreferenceChang
         if (connection != null) {
             Range range = connection.getWordRangeAtCursor(WHITESPACE_SEPARATORS, 1);
             if (range != null) {
-                word = range.mWord;
+                word = range.mWord.toString();
             }
         }
         final ResearchLogger researchLogger = getInstance();