package com.zxt.dlna.util;

import android.content.Context;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;

public class ShakeListener implements SensorEventListener {
	
	// 速度阈值，当摇晃速度达到这值后产生作用
	private static final int SPEED_SHRESHOLD = 4000;
	// 两次检测的时间间隔
	private static final int UPTATE_INTERVAL_TIME = 70;
	// 传感器管理器
	private SensorManager sensorManager;
	// 传感器
	private Sensor sensor;
	// 重力感应监听器
	private OnShakeListener onShakeListener;
	// 上下文
	private Context context;
	// 手机上一个位置时重力感应坐标
	private float lastX;
	private float lastY;
	private float lastZ;

	// 上次检测时间
	private long lastUpdateTime;

	public ShakeListener(Context c) {
		// 获得监听对象
		context = c;
		start();
	}

	// 开始
	public void start() {
		sensorManager = (SensorManager) context
				.getSystemService(Context.SENSOR_SERVICE);
		// 获得传感器管理器
		if (sensorManager != null) {
			// 获得重力传感器
			sensor = sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
		}
		// 注册
		if (sensor != null) {
			sensorManager.registerListener(this, sensor,
					SensorManager.SENSOR_DELAY_GAME);
		}
	}

	public void stop() {
		sensorManager.unregisterListener(this);
	}

	@Override
	public void onAccuracyChanged(Sensor arg0, int arg1) {
		// TODO Auto-generated method stub
	}

	// 重力感应器感应获得变化数据
	@Override
	public void onSensorChanged(SensorEvent event) {
		// 现在检测时间
		long currentUpdateTime = System.currentTimeMillis();
		// 两次检测的时间间隔
		long timeInterval = currentUpdateTime - lastUpdateTime;
		//判断是否达到了检测时间间隔
		if(timeInterval < UPTATE_INTERVAL_TIME){
			return;
		}
		//现在的时间变成last时间
		lastUpdateTime = currentUpdateTime;
		
		//获得x,y,z坐标
		float x = event.values[0];
		float y = event.values[1];
		float z = event.values[2];
		
		//获得x,y,z的变化值
		float deltaX = x - lastX;
		float deltaY = y - lastY;
		float deltaZ = z - lastZ;
		
		//将现在的坐标变成last坐标
		lastX = x;
		lastY = y;
		lastZ = z;
		
		double speed = Math.sqrt(deltaX*deltaX + deltaY*deltaY + deltaZ*deltaZ)/timeInterval * 10000;
		//达到速度阀值，发出提示
		if(speed >= SPEED_SHRESHOLD){
			onShakeListener.onShake();
		}
		
	}

	// 摇晃监听接口
	public interface OnShakeListener {
		public void onShake();
	}

	// 设置重力感应监听器
	public void setOnShakeListener(OnShakeListener listener) {
		onShakeListener = listener;
	}
}