import android.media.MediaRecorder;
import android.util.Log;
import java.io.File;
import java.io.IOException;
import java.io.RandomAccessFile;
/**
 * 錄音工具
 */
public class RecorderUtil {
  private static final String TAG = "RecorderUtil";
  private String mFileName = null;
  private MediaRecorder mRecorder = null;
  private long startTime;
  private long timeInterval;
  private boolean isRecording;
  public RecorderUtil(){
    mFileName = FileUtil.getCacheFilePath("tempAudio");
  }
  /**
   * 開始錄音
   */
  public void startRecording() {
    if (mFileName == null) return;
    if (isRecording){
      mRecorder.release();
      mRecorder = null;
    }
    mRecorder = new MediaRecorder();
    mRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
    mRecorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4);
    mRecorder.setOutputFile(mFileName);
    mRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AAC);
    startTime = System.currentTimeMillis();
    try {
      mRecorder.prepare();
      mRecorder.start();
      isRecording = true;
    } catch (Exception e){
      Log.e(TAG, "prepare() failed");
    }
  }
  /**
   * 停止錄音
   */
  public void stopRecording() {
    if (mFileName == null) return;
    timeInterval = System.currentTimeMillis() - startTime;
    try{
      if (timeInterval>1000){
        mRecorder.stop();
      }
      mRecorder.release();
      mRecorder = null;
      isRecording =false;
    }catch (Exception e){
      Log.e(TAG, "release() failed");
    }
  }
  /**
   * 取消語音
   */
  public synchronized void cancelRecording() {
    if (mRecorder != null) {
      try {
        mRecorder.release();
        mRecorder = null;
      } catch (Exception e) {
        e.printStackTrace();
      }
      File file = new File(mFileName);
      file.deleteOnExit();
    }
    isRecording =false;
  }
  /**
   * 獲取錄音文件
   */
  public byte[] getDate() {
    if (mFileName == null) return null;
    try{
      return readFile(new File(mFileName));
    }catch (IOException e){
      Log.e(TAG, "read file error" + e);
      return null;
    }
  }
  /**
   * 獲取錄音文件地址
   */
  public String getFilePath(){
    return mFileName;
  }
  /**
   * 獲取錄音時長,單位秒
   */
  public long getTimeInterval() {
    return timeInterval/1000;
  }
  /**
   * 將文件轉化為byte[]
   *
   * @param file 輸入文件
   */
  private static byte[] readFile(File file) throws IOException {
    // Open file
    RandomAccessFile f = new RandomAccessFile(file, "r");
    try {
      // Get and check length
      long longlength = f.length();
      int length = (int) longlength;
      if (length != longlength)
        throw new IOException("File size >= 2 GB");
      // Read file and return data
      byte[] data = new byte[length];
      f.readFully(data);
      return data;
    } finally {
      f.close();
    }
  }
}