#!/bin/bash
# based on GtkGrab by @EvanDotPro https://github.com/EvanDotPro/GtkGrab
function rename_file()
{
    NEWFILE=$(echo $1 | md5sum | cut -c-5)'.png'
}
REMOTE=user@domain.tld:/home/user/screens/
DOMAIN=http://i.domain.tld/
LOCALPATH=/home/user/Pictures/screenshots/
xfce4-screenshooter -r --save=$LOCALPATH
LOCALFILE=$(ls -tr $LOCALPATH | tail -n 1)
rename_file $LOCALFILE
I=0
LIMIT=10
while [ "$I" -lt "$LIMIT" -a -f "$LOCALPATH$NEWFILE" ]
do
    rename_file $NEWFILE
    I=`expr $I + 1`
done
mv "$LOCALPATH$LOCALFILE" "$LOCALPATH$NEWFILE"
scp "$LOCALPATH$NEWFILE" "$REMOTE$NEWFILE"
echo "$DOMAIN$NEWFILE" | xclip -selection clipboard
notify-send "Screenshot uploaded, URL in clipboard"

I'm currently trying to fix a Mockery bug and, while deep in the code, I came across a piece of code which gets eval'd. Mainly to understand better what's going on, I wanted to step debug it. I first set a breakpoint before the eval call and then tried to step into the eval'd code, but that didn't work out, Netbeans just moves along to the next line.

What *did* work, is setting a xdebug_break() call inside of the code that will be eval'd - and BAM! it works! Netbeans picks up the signal and everything works just as with regular code - you can view the values of the variables, step in, step out and step over code.

Xdebug is full of awesome.

Happy hackin'!

What did we get?

As we want our script to receive messages from an other account, first we need to listen to the ReceivedImMsg event on the im.pidgin.purple.PurpleInterface interface. The data we get with that event is the ID of receiver's account, the sender of the message, the actual message and the conversation's ID (and some flags which we're not interested in):

$interface = "im.pidgin.purple.PurpleInterface";
$method = "ReceivedImMsg";
if ($signal->matches($interface, $method)) {
    $data = $signal->getData()->getData();
    $receiver = $data[0];
    $sender = $data[1];
    $message = $data[2];
    $conversation = $data[3];
}

Of course, this is only for this one event, for data associated with other events see Pidgin's manual.

Who's there?

The event we are listening for will fire for any and all accounts, no matter who is the sender or the receiver of the message. We need to make sure that the receiving and the sending accounts are the correct ones, that the receiver is connected and that the receiver and the sender are contacts, "buddies":

if ($receiver == 2034 && $proxy->PurpleAccountIsConnected($receiver)
    && $proxy->PurpleFindBuddy($receiver, $sender) == 3681) {

The numbers 2034 and 3681 are the account IDs for my accounts I used in this example; you'll need to figure out yours.

Sending a response

Now that we know who's talking to whom, we can act upon the received message, do something with it, create a response message and send it back! The data we got with the event, has the ID of the conversation between the two accounts. We create a new instant message for that conversation and send it on it's merry way with our clever response message:

$im = $proxy->PurpleConvIm($conversation);
$proxy->PurpleConvImSend($im, $responseMessage);

As for what action the script can take upon a new message, is really up to the developer: it can do simple stuff like sending back the current uptime of the server or the current IP, running other tools like usher and sending that result back, or whatever is necessary.

Daemonizing

As this little bot is supposed to run on some server, the easiest way to run it as a "daemon" is to put the script in a background job via nohup:

$ nohup php chat.php &

If needed, creating daemons in PHP can be done too.

And that's about all what's needed to create a chat bot. See a complete example here on Github.

As for, is PHP the right tool for creating this kind of thing, I don't know, maybe, maybe not. What I do know, is that I had fun writing all this and I learned a lot along the way :)

Happy hackin'!