#!/bin/bash 

LOGFILE="/var/log/chromium-monitor.log"

get_monitor() {
    sudo cat /var/lib/dhcp/* | grep -a "option monitor" | tail -1 | \
    awk '{ s = ""; for (i = 3; i <= NF; i++) s = s $i " "; print s}' | \
    awk -F '"' '{print $2}'
}

get_current_window() {
    DISPLAY=:0 xdotool getwindowfocus getwindowname | awk -F '- Chromium' '{print $1}'
}

monitor=""
while [ -z "$monitor" ]; do
    monitor=$(get_monitor)
    echo "Current monitor: $monitor" >> $LOGFILE  # Debug output
    if [ -z "$monitor" ]; then
        sleep 5
    fi
done

monitor_md5=$(echo -n ${monitor^^} | sed -e 's/^[[:space:]]*//' | md5sum | awk '{print $1}')
echo "Monitor MD5: $monitor_md5" >> $LOGFILE  # Debug output

while true; do
    new_monitor=$(get_monitor)
    new_current=$(get_current_window)

    # Log the current state
    echo "New monitor: $new_monitor" >> $LOGFILE  # Debug output
    echo "New current window: $new_current" >> $LOGFILE  # Debug output

    if [ -n "$new_monitor" ] && [ -n "$new_current" ]; then
        new_monitor_md5=$(echo -n ${new_monitor^^} | sed -e 's/^[[:space:]]*//' | md5sum | awk '{print $1}')
        current_md5=$(echo -n ${new_current^^} | sed -e 's/^[[:space:]]*//' | md5sum | awk '{print $1}')

        # Log the computed MD5 hashes
        echo "New monitor MD5: $new_monitor_md5" >> $LOGFILE  # Debug output
        echo "Current window MD5: $current_md5" >> $LOGFILE  # Debug output

        if [ "$new_monitor_md5" != "$monitor_md5" ] && [ "$current_md5" != "$monitor_md5" ]; then
            echo "Mismatch detected. Rebooting now." >> $LOGFILE
            sudo reboot
            exit 1
        fi
    else
        echo "Either monitor or current is not available, skipping check." >> $LOGFILE
    fi

    # Log the status before sleeping
    echo "Sleeping for 5 seconds before the next check..." >> $LOGFILE
    sleep 5s
done

#  Version 1.0:
#  Created 2024 by Tim Eertmoed, Christian Hampp @ WiS IT-Solutions GmbH, Germany to work on Raspian as custom pxe init script.