scripts/unlock_adb_device.sh

#!/bin/sh

unlock() {
	### Activates the screen and unlocks the phone
	# Reads the current screen state eturns any combination of ON/OFF and
	# LOCKED/UNLOCKED (i.e. OFF_LOCKED).
	# Works only on NFC enabled phones but alternative methods exist.
	IFS='_' read -ra screenstate <<< $(adb shell dumpsys nfc | awk -F'=' \
		'/mScreenState/ {print $2}')
	# Emulate Power-Button press if screen is OFF.
	[ "${screenstate[0]}" == "OFF" ] && adb shell input keyevent 26 && \
		echo Screen activated
	# Emulate Menu-button press if phone is locked. Requires the phone to
	# unlock without PIN or password.
	[ "${screenstate[1]}" == "LOCKED" ] && adb shell input keyevent 82 && \
		echo Device unlocked
}

blank() {
	### Blanks the screen (optionally wait X seconds)
	[ -z "${1}" ] && sleep "${1}"
	IFS='_' read -ra screenstate <<< $(adb shell dumpsys nfc | awk -F'=' \
		'/mScreenState/ {print $2}')
	[ "${screenstate[0]}" == "ON" ] && adb shell input keyevent 26 && \
		echo Screen deactivated
}

run() {
	# Unlock phone
	unlock
	# Start intent
	[ -z "${1}" ] && APP="com.dev47apps.obsdroidcam" || APP="${1}"
	adb shell am start -n "${APP}/.MainActivity"
	blank 5
}

usage() {
	echo "Usage: ${0} [-u|b] [-r INTENT]

	-u		unlock device (default if no option is given)
	-b		blank device screen
	-r INTENT	unlock device, run given intent and blank device screen
	-h 		this help"
}

while getopts ":ubr:h" opt; do
	case "${opt}" in
		u) unlock ;;
		b) blank ;;
		r) run "${OPTARG}" ;;
		h) usage ;;
		*) unlock ;;
	esac
done