1 files changed, 181 insertions, 0 deletions
diff --git a/java/src/com/android/inputmethod/keyboard/internal/BatchInputArbiter.java b/java/src/com/android/inputmethod/keyboard/internal/BatchInputArbiter.java
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index 000000000..cd9875955
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+++ b/java/src/com/android/inputmethod/keyboard/internal/BatchInputArbiter.java
@@ -0,0 +1,181 @@
+/*
+ * 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 com.android.inputmethod.keyboard.internal;
+
+import com.android.inputmethod.latin.Constants;
+import com.android.inputmethod.latin.InputPointers;
+
+/**
+ * This class arbitrates batch input.
+ * An instance of this class holds a {@link GestureStrokeRecognitionPoints}.
+ * And it arbitrates multiple strokes gestured by multiple fingers and aggregates those gesture
+ * points into one batch input.
+ */
+public class BatchInputArbiter {
+    public interface BatchInputArbiterListener {
+        public void onStartBatchInput();
+        public void onUpdateBatchInput(
+                final InputPointers aggregatedPointers, final long moveEventTime);
+        public void onStartUpdateBatchInputTimer();
+        public void onEndBatchInput(final InputPointers aggregatedPointers, final long upEventTime);
+    }
+
+    // The starting time of the first stroke of a gesture input.
+    private static long sGestureFirstDownTime;
+    // The {@link InputPointers} that includes all events of a gesture input.
+    private static final InputPointers sAggregatedPointers = new InputPointers(
+            Constants.DEFAULT_GESTURE_POINTS_CAPACITY);
+    private static int sLastRecognitionPointSize = 0; // synchronized using sAggregatedPointers
+    private static long sLastRecognitionTime = 0; // synchronized using sAggregatedPointers
+
+    private final GestureStrokeRecognitionPoints mRecognitionPoints;
+
+    public BatchInputArbiter(final int pointerId, final GestureStrokeRecognitionParams params) {
+        mRecognitionPoints = new GestureStrokeRecognitionPoints(pointerId, params);
+    }
+
+    public void setKeyboardGeometry(final int keyWidth, final int keyboardHeight) {
+        mRecognitionPoints.setKeyboardGeometry(keyWidth, keyboardHeight);
+    }
+
+    /**
+     * Calculate elapsed time since the first gesture down.
+     * @param eventTime the time of this event.
+     * @return the elapsed time in millisecond from the first gesture down.
+     */
+    public int getElapsedTimeSinceFirstDown(final long eventTime) {
+        return (int)(eventTime - sGestureFirstDownTime);
+    }
+
+    /**
+     * Add a down event point.
+     * @param x the x-coordinate of this down event.
+     * @param y the y-coordinate of this down event.
+     * @param downEventTime the time of this down event.
+     * @param lastLetterTypingTime the last typing input time.
+     * @param activePointerCount the number of active pointers when this pointer down event occurs.
+     */
+    public void addDownEventPoint(final int x, final int y, final long downEventTime,
+            final long lastLetterTypingTime, final int activePointerCount) {
+        if (activePointerCount == 1) {
+            sGestureFirstDownTime = downEventTime;
+        }
+        final int elapsedTimeSinceFirstDown = getElapsedTimeSinceFirstDown(downEventTime);
+        final int elapsedTimeSinceLastTyping = (int)(downEventTime - lastLetterTypingTime);
+        mRecognitionPoints.addDownEventPoint(
+                x, y, elapsedTimeSinceFirstDown, elapsedTimeSinceLastTyping);
+    }
+
+    /**
+     * Add a move event point.
+     * @param x the x-coordinate of this move event.
+     * @param y the y-coordinate of this move event.
+     * @param moveEventTime the time of this move event.
+     * @param isMajorEvent false if this is a historical move event.
+     * @param listener {@link BatchInputArbiterListener#onStartUpdateBatchInputTimer()} of this
+     *     <code>listener</code> may be called if enough move points have been added.
+     * @return true if this move event occurs on the valid gesture area.
+     */
+    public boolean addMoveEventPoint(final int x, final int y, final long moveEventTime,
+            final boolean isMajorEvent, final BatchInputArbiterListener listener) {
+        final int beforeLength = mRecognitionPoints.getLength();
+        final boolean onValidArea = mRecognitionPoints.addEventPoint(
+                x, y, getElapsedTimeSinceFirstDown(moveEventTime), isMajorEvent);
+        if (mRecognitionPoints.getLength() > beforeLength) {
+            listener.onStartUpdateBatchInputTimer();
+        }
+        return onValidArea;
+    }
+
+    /**
+     * Determine whether the batch input has started or not.
+     * @param listener {@link BatchInputArbiterListener#onStartBatchInput()} of this
+     *     <code>listener</code> will be called when the batch input has started successfully.
+     * @return true if the batch input has started successfully.
+     */
+    public boolean mayStartBatchInput(final BatchInputArbiterListener listener) {
+        if (!mRecognitionPoints.isStartOfAGesture()) {
+            return false;
+        }
+        synchronized (sAggregatedPointers) {
+            sAggregatedPointers.reset();
+            sLastRecognitionPointSize = 0;
+            sLastRecognitionTime = 0;
+            listener.onStartBatchInput();
+        }
+        return true;
+    }
+
+    /**
+     * Add synthetic move event point. After adding the point,
+     * {@link #updateBatchInput(long,BatchInputArbiterListener)} will be called internally.
+     * @param syntheticMoveEventTime the synthetic move event time.
+     * @param listener the listener to be passed to
+     *     {@link #updateBatchInput(long,BatchInputArbiterListener)}.
+     */
+    public void updateBatchInputByTimer(final long syntheticMoveEventTime,
+            final BatchInputArbiterListener listener) {
+        mRecognitionPoints.duplicateLastPointWith(
+                getElapsedTimeSinceFirstDown(syntheticMoveEventTime));
+        updateBatchInput(syntheticMoveEventTime, listener);
+    }
+
+    /**
+     * Determine whether we have enough gesture points to lookup dictionary.
+     * @param moveEventTime the time of this move event.
+     * @param listener {@link BatchInputArbiterListener#onUpdateBatchInput(InputPointers,long)} of
+     *     this <code>listener</code> will be called when enough event points we have. Also
+     *     {@link BatchInputArbiterListener#onStartUpdateBatchInputTimer()} will be called to have
+     *     possible future synthetic move event.
+     */
+    public void updateBatchInput(final long moveEventTime,
+            final BatchInputArbiterListener listener) {
+        synchronized (sAggregatedPointers) {
+            mRecognitionPoints.appendIncrementalBatchPoints(sAggregatedPointers);
+            final int size = sAggregatedPointers.getPointerSize();
+            if (size > sLastRecognitionPointSize && mRecognitionPoints.hasRecognitionTimePast(
+                    moveEventTime, sLastRecognitionTime)) {
+                listener.onUpdateBatchInput(sAggregatedPointers, moveEventTime);
+                listener.onStartUpdateBatchInputTimer();
+                // The listener may change the size of the pointers (when auto-committing
+                // for example), so we need to get the size from the pointers again.
+                sLastRecognitionPointSize = sAggregatedPointers.getPointerSize();
+                sLastRecognitionTime = moveEventTime;
+            }
+        }
+    }
+
+    /**
+     * Determine whether the batch input has ended successfully or continues.
+     * @param upEventTime the time of this up event.
+     * @param activePointerCount the number of active pointers when this pointer up event occurs.
+     * @param listener {@link BatchInputArbiterListener#onEndBatchInput(InputPointers,long)} of this
+     *     <code>listener</code> will be called when the batch input has started successfully.
+     * @return true if the batch input has ended successfully.
+     */
+    public boolean mayEndBatchInput(final long upEventTime, final int activePointerCount,
+            final BatchInputArbiterListener listener) {
+        synchronized (sAggregatedPointers) {
+            mRecognitionPoints.appendAllBatchPoints(sAggregatedPointers);
+            if (activePointerCount == 1) {
+                listener.onEndBatchInput(sAggregatedPointers, upEventTime);
+                return true;
+            }
+        }
+        return false;
+    }
+}