/// <summary>
/// Get a screenshot, either via wifi or via bluetooth
/// </summary>
public async void Screenshot()
{
if (HasWifi)
{
// wifi connection is enabled, try getting a screenshot via wifi first.
Task <byte[]> task = wifi.GetScreenshot();
CancellationTokenSource CancelDelay = new CancellationTokenSource();
CancellationTokenSource CancelFetch = new CancellationTokenSource();
// Wait maximum 1.5s for the screenshot over wifi
if (await Task.WhenAny(task, Task.Delay(1500, CancelDelay.Token)) == task)
{
// GetScreenshot() returned before the timeout, let's check the result
byte[] picbuf = await task;
CancelDelay.Cancel(); // Cancel the timeout delay, it's no longer needed
if (picbuf == null)
{
// Wifi failed somehow, fallback to bluetooth and disable the wifi client
handler.UpdateStatus("Connected (wifi errors)");
HasWifi = false;
wifi = null;
bt.Send("sc");
}
else
{
// Successfully got a screenshot over wifi
Bitmap bitmap = BitmapFactory.DecodeByteArray(picbuf, 0, picbuf.Length);
Console.WriteLine("Bitmap (from wifi) ready, sending over to main thread");
handler.ObtainMessage((int)UIUpdateHandler.MessageType.BITMAP, bitmap).SendToTarget();
}
}
else
{
// Timeout from wifi... fallback to bluetooth
WifiTimeoutCount++;
bt.Send("sc");
if (bt.state == BluetoothClient.State.CONNECTED)
{
handler.UpdateStatus("Connected (flakey wifi?)");
}
if (WifiTimeoutCount > 2)
{
// WiFi timed-out three times, and therefor is not to be trusted.
HasWifi = false;
wifi = null;
if (bt.state == BluetoothClient.State.CONNECTED)
{
handler.UpdateStatus("Connected (wifi disabled)");
}
}
}
}
else
{
// No wifi, just ask for a screenshot over Bluetooth
bt.Send("sc");
}
}
void Recieve()
{
while (true)
{
try
{
if (paused)
{
continue;
}
if (state != State.CONNECTED)
{
StateChangedEvent.WaitOne();
continue;
}
byte[] buf = new byte[4]; // 4 bytes for "pic:" or "pong"
int expected_size = 0;
if (_recieve_state == RecieveState.PINGPONG)
{
lock (InStream)
{
InStream.Read(buf, 0, buf.Length);
}
last_ping = DateTime.UtcNow;
String command = Encoding.ASCII.GetString(buf).Trim();
if (command.StartsWith("pic"))
{
buf = new byte[8]; // 8 bytes for image size
InStream.Read(buf, 0, buf.Length);
expected_size = Int32.Parse(Encoding.ASCII.GetString(buf).Trim());
Console.WriteLine("Expecting a picture, {0} bytes", expected_size);
_recieve_state = RecieveState.PICTURE;
}
else if (command.StartsWith("wifi"))
{
Console.WriteLine(command);
buf = new byte[4]; // 4 bytes for recieved handshake json length
InStream.Read(buf, 0, buf.Length);
Console.WriteLine(Encoding.ASCII.GetString(buf));
expected_size = Int32.Parse(Encoding.ASCII.GetString(buf).Trim());
buf = Common.ReadAll(InStream, expected_size);
WifiCallback(buf);
}
else if (command != "pong")
{
// Unexpected data in buffer...
// Recover by reconnecting?
Console.WriteLine("junk on the buffer :( '" + command + "'");
Disconnect();
Connect(this.device);
}
}
// This is a regular if, not an else if!
if (_recieve_state == RecieveState.PICTURE)
{
byte[] picbuf = Common.ReadAll(InStream, expected_size, 8192 * 2);
Console.WriteLine("Recieved picture? {0} bytes", picbuf.Length);
Bitmap bitmap = BitmapFactory.DecodeByteArray(picbuf, 0, picbuf.Length);
Console.WriteLine("Bitmap (hopefully) ready, sending over to main thread");
handler.ObtainMessage(0, bitmap).SendToTarget();
_recieve_state = RecieveState.PINGPONG;
}
}
catch (Java.IO.IOException e)
{
Console.WriteLine("Recieving failed, connection might be lost");
Console.WriteLine(e);
SetState(State.NOT_CONNECTED);
Connect(device);
}
}
}
