use `cec-client` to fire events when keys are pressed

cec-keypresses.sh

#!/usr/bin/env bash
#
# react to cec keypresses and inject Wayland key events via wtype
#
# Author: Dave Eddy <[email protected]>
# License: MIT
# Modified: dedup filter + wtype mapping
#

onright() {
  echo 'right button pressed'
  wtype -k Right
}
onleft() {
  echo 'left button pressed'
  wtype -k Left
}
ondown() {
  echo 'down button pressed'
  wtype -k Down
}
onup() {
  echo 'up button pressed'
  wtype -k Up
}
onselect() {
  echo 'select button pressed'
  wtype -k Return
}
onexit() {
  echo 'exit button pressed'
  wtype -k Escape
}
onplay() {
  echo 'play button pressed'
  wtype -k space
}
onpause() {
  echo 'pause button pressed'
  wtype -k space
}
onforward() {
  echo 'forward button pressed'
  wtype -k F
}
onbackward() {
  echo 'backward button pressed'
  wtype -k R
}

filter() {
	perl -nle '
	BEGIN { $|=1 }
	if (/key pressed: (.*) \(/) {
		$key=$1;
		if ($key ne $last) {
			print $key;
			$last=$key;
		}
	}
	if (/key released: (.*) \(/) {
		$last="";
	}
	'
}

echo as | cec-client | filter | \
while read cmd; do
	case "$cmd" in
    right)     onright;;
    left)      onleft;;
    down)      ondown;;
    up)        onup;;
    select)    onselect;;
    exit)      onexit;;
    play)      onplay;;
    pause)     onpause;;
    forward)   onforward;;
    backward)  onbackward;;
    *)         echo "unrecognized button ($cmd)";;
	esac
done

install-libcec.md

install libcec on raspbian

sudo apt-get update
sudo apt-get install build-essential autoconf liblockdev1-dev libudev-dev git libtool pkg-config
git clone https://github.com/Pulse-Eight/libcec
cd libcec
./bootstrap
./configure --with-rpi-include-path=/opt/vc/include --with-rpi-lib-path=/opt/vc/lib --enable-rpi
make
sudo make install
sudo ln -s /usr/local/lib/libcec.so /usr/lib/
sudo ln -s /usr/local/lib/libcec.so.2 /usr/lib/

run cec-keypresses.sh

~$ ./cec-keypresses.sh 
right button pressed
right button pressed
left button pressed
up button pressed
down button pressed
select button pressed
select button pressed