1 files changed, 221 insertions, 0 deletions
diff --git a/java/src/org/kelar/inputmethod/latin/inputlogic/InputLogicHandler.java b/java/src/org/kelar/inputmethod/latin/inputlogic/InputLogicHandler.java
new file mode 100644
index 000000000..513d8785c
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+++ b/java/src/org/kelar/inputmethod/latin/inputlogic/InputLogicHandler.java
@@ -0,0 +1,221 @@
+/*
+ * Copyright (C) 2013 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 org.kelar.inputmethod.latin.inputlogic;
+
+import android.os.Handler;
+import android.os.HandlerThread;
+import android.os.Message;
+
+import org.kelar.inputmethod.compat.LooperCompatUtils;
+import org.kelar.inputmethod.latin.LatinIME;
+import org.kelar.inputmethod.latin.SuggestedWords;
+import org.kelar.inputmethod.latin.Suggest.OnGetSuggestedWordsCallback;
+import org.kelar.inputmethod.latin.common.InputPointers;
+
+/**
+ * A helper to manage deferred tasks for the input logic.
+ */
+class InputLogicHandler implements Handler.Callback {
+    final Handler mNonUIThreadHandler;
+    // TODO: remove this reference.
+    final LatinIME mLatinIME;
+    final InputLogic mInputLogic;
+    private final Object mLock = new Object();
+    private boolean mInBatchInput; // synchronized using {@link #mLock}.
+
+    private static final int MSG_GET_SUGGESTED_WORDS = 1;
+
+    // A handler that never does anything. This is used for cases where events come before anything
+    // is initialized, though probably only the monkey can actually do this.
+    public static final InputLogicHandler NULL_HANDLER = new InputLogicHandler() {
+        @Override
+        public void reset() {}
+        @Override
+        public boolean handleMessage(final Message msg) { return true; }
+        @Override
+        public void onStartBatchInput() {}
+        @Override
+        public void onUpdateBatchInput(final InputPointers batchPointers,
+                final int sequenceNumber) {}
+        @Override
+        public void onCancelBatchInput() {}
+        @Override
+        public void updateTailBatchInput(final InputPointers batchPointers,
+                final int sequenceNumber) {}
+        @Override
+        public void getSuggestedWords(final int sessionId, final int sequenceNumber,
+                final OnGetSuggestedWordsCallback callback) {}
+    };
+
+    InputLogicHandler() {
+        mNonUIThreadHandler = null;
+        mLatinIME = null;
+        mInputLogic = null;
+    }
+
+    public InputLogicHandler(final LatinIME latinIME, final InputLogic inputLogic) {
+        final HandlerThread handlerThread = new HandlerThread(
+                InputLogicHandler.class.getSimpleName());
+        handlerThread.start();
+        mNonUIThreadHandler = new Handler(handlerThread.getLooper(), this);
+        mLatinIME = latinIME;
+        mInputLogic = inputLogic;
+    }
+
+    public void reset() {
+        mNonUIThreadHandler.removeCallbacksAndMessages(null);
+    }
+
+    // In unit tests, we create several instances of LatinIME, which results in several instances
+    // of InputLogicHandler. To avoid these handlers lingering, we call this.
+    public void destroy() {
+        LooperCompatUtils.quitSafely(mNonUIThreadHandler.getLooper());
+    }
+
+    /**
+     * Handle a message.
+     * @see android.os.Handler.Callback#handleMessage(android.os.Message)
+     */
+    // Called on the Non-UI handler thread by the Handler code.
+    @Override
+    public boolean handleMessage(final Message msg) {
+        switch (msg.what) {
+            case MSG_GET_SUGGESTED_WORDS:
+                mLatinIME.getSuggestedWords(msg.arg1 /* inputStyle */,
+                        msg.arg2 /* sequenceNumber */, (OnGetSuggestedWordsCallback) msg.obj);
+                break;
+        }
+        return true;
+    }
+
+    // Called on the UI thread by InputLogic.
+    public void onStartBatchInput() {
+        synchronized (mLock) {
+            mInBatchInput = true;
+        }
+    }
+
+    public boolean isInBatchInput() {
+        return mInBatchInput;
+    }
+
+    /**
+     * Fetch suggestions corresponding to an update of a batch input.
+     * @param batchPointers the updated pointers, including the part that was passed last time.
+     * @param sequenceNumber the sequence number associated with this batch input.
+     * @param isTailBatchInput true if this is the end of a batch input, false if it's an update.
+     */
+    // This method can be called from any thread and will see to it that the correct threads
+    // are used for parts that require it. This method will send a message to the Non-UI handler
+    // thread to pull suggestions, and get the inlined callback to get called on the Non-UI
+    // handler thread. If this is the end of a batch input, the callback will then proceed to
+    // send a message to the UI handler in LatinIME so that showing suggestions can be done on
+    // the UI thread.
+    private void updateBatchInput(final InputPointers batchPointers,
+            final int sequenceNumber, final boolean isTailBatchInput) {
+        synchronized (mLock) {
+            if (!mInBatchInput) {
+                // Batch input has ended or canceled while the message was being delivered.
+                return;
+            }
+            mInputLogic.mWordComposer.setBatchInputPointers(batchPointers);
+            final OnGetSuggestedWordsCallback callback = new OnGetSuggestedWordsCallback() {
+                @Override
+                public void onGetSuggestedWords(final SuggestedWords suggestedWords) {
+                    showGestureSuggestionsWithPreviewVisuals(suggestedWords, isTailBatchInput);
+                }
+            };
+            getSuggestedWords(isTailBatchInput ? SuggestedWords.INPUT_STYLE_TAIL_BATCH
+                    : SuggestedWords.INPUT_STYLE_UPDATE_BATCH, sequenceNumber, callback);
+        }
+    }
+
+    void showGestureSuggestionsWithPreviewVisuals(final SuggestedWords suggestedWordsForBatchInput,
+            final boolean isTailBatchInput) {
+        final SuggestedWords suggestedWordsToShowSuggestions;
+        // We're now inside the callback. This always runs on the Non-UI thread,
+        // no matter what thread updateBatchInput was originally called on.
+        if (suggestedWordsForBatchInput.isEmpty()) {
+            // Use old suggestions if we don't have any new ones.
+            // Previous suggestions are found in InputLogic#mSuggestedWords.
+            // Since these are the most recent ones and we just recomputed
+            // new ones to update them, then the previous ones are there.
+            suggestedWordsToShowSuggestions = mInputLogic.mSuggestedWords;
+        } else {
+            suggestedWordsToShowSuggestions = suggestedWordsForBatchInput;
+        }
+        mLatinIME.mHandler.showGesturePreviewAndSuggestionStrip(suggestedWordsToShowSuggestions,
+                isTailBatchInput /* dismissGestureFloatingPreviewText */);
+        if (isTailBatchInput) {
+            mInBatchInput = false;
+            // The following call schedules onEndBatchInputInternal
+            // to be called on the UI thread.
+            mLatinIME.mHandler.showTailBatchInputResult(suggestedWordsToShowSuggestions);
+        }
+    }
+
+    /**
+     * Update a batch input.
+     *
+     * This fetches suggestions and updates the suggestion strip and the floating text preview.
+     *
+     * @param batchPointers the updated batch pointers.
+     * @param sequenceNumber the sequence number associated with this batch input.
+     */
+    // Called on the UI thread by InputLogic.
+    public void onUpdateBatchInput(final InputPointers batchPointers,
+            final int sequenceNumber) {
+        updateBatchInput(batchPointers, sequenceNumber, false /* isTailBatchInput */);
+    }
+
+    /**
+     * Cancel a batch input.
+     *
+     * Note that as opposed to updateTailBatchInput, we do the UI side of this immediately on the
+     * same thread, rather than get this to call a method in LatinIME. This is because
+     * canceling a batch input does not necessitate the long operation of pulling suggestions.
+     */
+    // Called on the UI thread by InputLogic.
+    public void onCancelBatchInput() {
+        synchronized (mLock) {
+            mInBatchInput = false;
+        }
+    }
+
+    /**
+     * Trigger an update for a tail batch input.
+     *
+     * A tail batch input is the last update for a gesture, the one that is triggered after the
+     * user lifts their finger. This method schedules fetching suggestions on the non-UI thread,
+     * then when the suggestions are computed it comes back on the UI thread to update the
+     * suggestion strip, commit the first suggestion, and dismiss the floating text preview.
+     *
+     * @param batchPointers the updated batch pointers.
+     * @param sequenceNumber the sequence number associated with this batch input.
+     */
+    // Called on the UI thread by InputLogic.
+    public void updateTailBatchInput(final InputPointers batchPointers,
+            final int sequenceNumber) {
+        updateBatchInput(batchPointers, sequenceNumber, true /* isTailBatchInput */);
+    }
+
+    public void getSuggestedWords(final int inputStyle, final int sequenceNumber,
+            final OnGetSuggestedWordsCallback callback) {
+        mNonUIThreadHandler.obtainMessage(
+                MSG_GET_SUGGESTED_WORDS, inputStyle, sequenceNumber, callback).sendToTarget();
+    }
+}