WifiTracker.java

package cri.sanity.util;

import cri.sanity.*;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.net.wifi.WifiManager;


public final class WifiTracker extends BroadcastReceiver
{
	private static final int ACT_NONE    = 0;
	private static final int ACT_ENABLE  = 1;
	private static final int ACT_DISABLE = 2;
	private static final int ENABLED     = WifiManager.WIFI_STATE_ENABLED;
	private static final int ENABLING    = WifiManager.WIFI_STATE_ENABLING;
	private static final int DISABLING   = WifiManager.WIFI_STATE_DISABLING;
	private static final int DISABLED    = WifiManager.WIFI_STATE_DISABLED;
	private static final int TASK_ACTION = Task.idNew();

	private int state, action;
	private boolean waiter;
	private final WifiManager wifiMan;

	private final Task taskAction = new Task() {
		@Override
		public void run() {
			synchronized(WifiTracker.this) {
				if(action == ACT_NONE) return;
				wifiMan.setWifiEnabled(action == ACT_ENABLE);
			}
		}
	};

	public WifiTracker()
	{
		wifiMan = A.wifiMan();
		state   = wifiMan.getWifiState();
		action  = ACT_NONE;
		waiter  = false;
		A.app().registerReceiver(this, new IntentFilter(WifiManager.WIFI_STATE_CHANGED_ACTION));
	}

	public synchronized void shutdown()
	{
		try {
			if(action != ACT_NONE) {
				waiter = true;
				wait(Conf.DEVS_MIN_RETRY * 2);
			}
		} catch(Exception e) {}
		try { A.app().unregisterReceiver(this); } catch(Exception e) {}
	}

	//public boolean isOn() { return state==ENABLED || state==ENABLING; }

	public synchronized boolean willOn() {
		return (action==ACT_NONE && (state==ENABLED || state==ENABLING)) || (action==ACT_ENABLE && Task.has(TASK_ACTION)) ;
	}

	@Override
	public synchronized void onReceive(Context ctx, Intent i)
	{
		state = i.getIntExtra(WifiManager.EXTRA_WIFI_STATE, WifiManager.WIFI_STATE_UNKNOWN);
		if(action != ACT_NONE) enable(action == ACT_ENABLE);
		if(waiter) notifyAll();
	}

	public synchronized void enable(boolean enable)
	{
		switch(state) {
			case DISABLING:
			case ENABLING:
				action = enable? ACT_ENABLE : ACT_DISABLE;
				break;
			case DISABLED:
				if(!enable)
					action = ACT_NONE;
				else {
					action = ACT_ENABLE; 
					if(!Task.has(TASK_ACTION)) taskAction.exec(TASK_ACTION, Conf.TRACKER_SWITCH_DELAY);
				}
				break;
			case ENABLED:
				if(enable)
					action = ACT_NONE;
				else {
					action = ACT_DISABLE; 
					if(!Task.has(TASK_ACTION)) taskAction.exec(TASK_ACTION, Conf.TRACKER_SWITCH_DELAY);
				}
				break;
			default:
				if(!enable)
					action = ACT_NONE;
				else {
					action = ACT_ENABLE; 
					if(!Task.has(TASK_ACTION)) taskAction.exec(TASK_ACTION, Conf.DEVS_MIN_RETRY);
				}
		}
		// A.logd("after wifi enable ("+enable+") : action="+action+", state="+state);
	}

}