birdcam-pi/poll_button.sh

#!/bin/sh

gpiocmd="$(command -v gpio)"

if [ -z "$gpiocmd" ]; then
	echo "Command gpio missing, try to install ..."
	
	echo "Check internet connection ..."
	pingserver="raspbian.raspberrypi.org"		### var: pingcheck destination
	if ! ping -q -c1 $pingserver>/dev/null; then
		echo "No internet connection ..."
		exit 0
	fi
	
	wget https://project-downloads.drogon.net/wiringpi-latest.deb
	sudo dpkg -i wiringpi-latest.deb
	rm wiringpi-latest.deb

#	sudo apt update; sudo apt -y install wiringpi
	
	gpiocmd="$(command -v gpio)"
	if [ -z "$gpiocmd" ]; then
		echo "cannot install wiringpi, exiting ..."
		exit 0
	fi
fi

gpiopin_sw="0"			### var: gpio switch
gpiopin_led_r="2"		### var: gpio led red
gpiopin_led_g="29"		### var: gpio led green


cameracmd="/home/pi/birdcam/view_birdcam.sh"	### var:  path to player script

buttonpolling="0.05"		### var: button polling in seconds
buttontimeout="1"		### var: button timeout in seconds
countermax="1200"		### var: counter max for automatic switching (countermax=time/buttonpolling)

$gpiocmd mode $gpiopin_led_g out
$gpiocmd write $gpiopin_led_g 0

while true; do

	counter="0"
	$gpiocmd mode $gpiopin_led_r out
	$gpiocmd write $gpiopin_led_g 1
	while [ "$($gpiocmd read $gpiopin_sw)" -eq "1" ] && [ "$counter" -lt "$countermax" ]; do
		counter="$(($counter + 1))"
		#echo "$counter"
		sleep $buttonpolling
	done

	$gpiocmd write $gpiopin_led_g 0
	$gpiocmd mode $gpiopin_led_r in
	camname="random"			### var: parameter for random video
	$cameracmd $camname &
	echo "$camname started!"
	sleep $buttontimeout

	counter="0"
	$gpiocmd mode $gpiopin_led_r out
	$gpiocmd write $gpiopin_led_g 1
	while [ "$($gpiocmd read $gpiopin_sw)" -eq "1" ] && [ "$counter" -lt "$countermax" ]; do
		counter="$(($counter + 1))"
		#echo "$counter"
		sleep $buttonpolling
	done

	$gpiocmd write $gpiopin_led_g 0
	$gpiocmd mode $gpiopin_led_r in
	camname="birdcam1"			### var: parameter for camera 1
	$cameracmd $camname &
	echo "$camname started!"
	sleep $buttontimeout

	counter="0"
	$gpiocmd mode $gpiopin_led_r out
	$gpiocmd write $gpiopin_led_g 1
	while [ "$($gpiocmd read $gpiopin_sw)" -eq "1" ] && [ "$counter" -lt "$countermax" ]; do
		counter="$(($counter + 1))"
		#echo "$counter"
		sleep $buttonpolling
	done
	
	$gpiocmd write $gpiopin_led_g 0
	$gpiocmd mode $gpiopin_led_r in
	camname="birdcam2"			### var: parameter for camera 2
	$cameracmd $camname &
	echo "$camname started!"
	sleep $buttontimeout

done