Add skeleton classes for hardware event flow (B1)

Bug: 5037589
Change-Id: Id8eea0e2bd00dd339a1efb4b0542e4c091a84195

1 files changed, 82 insertions, 0 deletions

diff --git a/java/src/com/android/inputmethod/event/EventInterpreter.java b/java/src/com/android/inputmethod/event/EventInterpreter.java
new file mode 100644
index 000000000..443c269a2
--- /dev/null
+++ b/java/src/com/android/inputmethod/event/EventInterpreter.java
@@ -0,0 +1,82 @@
+/*
+ * Copyright (C) 2012 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.event;
+
+import android.view.KeyEvent;
+
+/**
+ * This class implements the logic between receiving events and generating code points.
+ *
+ * Event sources are multiple. It may be a hardware keyboard, a D-PAD, a software keyboard,
+ * or any exotic input source.
+ * This class will orchestrate the decoding chain that starts with an event and ends up with
+ * a stream of code points + decoding state.
+ */
+public class EventInterpreter {
+    // TODO: Implement an object pool for events, as we'll create a lot of them
+    // TODO: Create a combiner
+    // TODO: Create an object type to represent input material + visual feedback + decoding state
+    // TODO: Create an interface to call back to Latin IME through the above object
+
+    // TODO: replace this with an associative container to bind device id -> decoder
+    HardwareEventDecoder mHardwareEventDecoder;
+    SoftwareEventDecoder mSoftwareEventDecoder;
+
+    public EventInterpreter() {
+        this(null);
+    }
+
+    public EventInterpreter(final EventDecoderSpec specification) {
+        // TODO: create the decoding chain from a specification. The decoders should be
+        // created lazily
+        mHardwareEventDecoder = new HardwareKeyboardEventDecoder(0);
+    }
+
+    // Helper method to decode a hardware key event into a generic event, and execute any
+    // necessary action.
+    public boolean onHardwareKeyEvent(final KeyEvent hardwareKeyEvent) {
+        final Event decodedEvent = getHardwareKeyEventDecoder(hardwareKeyEvent.getDeviceId())
+                .decodeHardwareKey(hardwareKeyEvent);
+        return onEvent(decodedEvent);
+    }
+
+    public boolean onSoftwareEvent() {
+        final Event decodedEvent = getSoftwareEventDecoder().decodeSoftwareEvent();
+        return onEvent(decodedEvent);
+    }
+
+    private HardwareEventDecoder getHardwareKeyEventDecoder(final int deviceId) {
+        // TODO: look up the decoder by device id. It should be created lazily
+        return mHardwareEventDecoder;
+    }
+
+    private SoftwareEventDecoder getSoftwareEventDecoder() {
+        return mSoftwareEventDecoder;
+    }
+
+    private boolean onEvent(final Event event) {
+        // TODO: Classify the event - input or non-input (see design doc)
+        // TODO: IF action event
+        //          Send decoded action back to LatinIME
+        //       ELSE
+        //          Send input event to the combiner
+        //          Get back new input material + visual feedback + combiner state
+        //          Route the event to Latin IME
+        //       ENDIF
+        return false;
+    }
+}