content: /*
   * Copyright (C) 2008 ZXing authors
   *
   * 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.xys.libzxing.zxing.utils;
  
  import android.app.Activity;
  import android.content.Intent;
  import android.os.Bundle;
  import android.os.Handler;
  import android.os.Message;
  
  import com.google.zxing.Result;
  import com.xys.libzxing.R;
  import com.xys.libzxing.zxing.activity.CaptureActivity;
  import com.xys.libzxing.zxing.camera.CameraManager;
  import com.xys.libzxing.zxing.decode.DecodeThread;
  
  /**
   * This class handles all the messaging which comprises the state machine for
   * capture.
   *
   * @author dswitkin@google.com (Daniel Switkin)
   */
  public class CaptureActivityHandler extends Handler {
  
      private final CaptureActivity activity;
      private final DecodeThread decodeThread;
      private final CameraManager cameraManager;
      private State state;
  
      public CaptureActivityHandler(CaptureActivity activity, CameraManager cameraManager, int decodeMode) {
          this.activity = activity;
          decodeThread = new DecodeThread(activity, decodeMode);
          decodeThread.start();
          state = State.SUCCESS;
  
          // Start ourselves capturing previews and decoding.
          this.cameraManager = cameraManager;
          cameraManager.startPreview();
          restartPreviewAndDecode();
      }
  
      @Override
      public void handleMessage(Message message) {
          if (message.what == R.id.restart_preview) {
              restartPreviewAndDecode();
  
          } else if (message.what == R.id.decode_succeeded) {
              state = State.SUCCESS;
              Bundle bundle = message.getData();
  
              activity.handleDecode((Result) message.obj, bundle);
  
          } else if (message.what == R.id.decode_failed) {// We're decoding as fast as possible, so when one
              // decode fails,
              // start another.
              state = State.PREVIEW;
              cameraManager.requestPreviewFrame(decodeThread.getHandler(), R.id.decode);
  
          } else if (message.what == R.id.return_scan_result) {
              activity.setResult(Activity.RESULT_OK, (Intent) message.obj);
              activity.finish();
  
          }
      }
  
      public void quitSynchronously() {
          state = State.DONE;
          cameraManager.stopPreview();
          Message quit = Message.obtain(decodeThread.getHandler(), R.id.quit);
          quit.sendToTarget();
          try {
              // Wait at most half a second; should be enough time, and onPause()
              // will timeout quickly
              decodeThread.join(500L);
          } catch (InterruptedException e) {
              // continue
          }
  
          // Be absolutely sure we don't send any queued up messages
          removeMessages(R.id.decode_succeeded);
          removeMessages(R.id.decode_failed);
      }
  
      private void restartPreviewAndDecode() {
          if (state == State.SUCCESS) {
              state = State.PREVIEW;
              cameraManager.requestPreviewFrame(decodeThread.getHandler(), R.id.decode);
          }
      }
  
      private enum State {
          PREVIEW, SUCCESS, DONE
      }
  
  }
  