#!/bin/sh
# we will need the suicide bashrc to continuously write DEAD to the nc socket
# in case two messages are sent at the same time.

# this will not work if your slbr admin is not in the "docker" group

PORT="$1"
LOG="log.txt"

[ -z "$1" ] && echo "port?" && exit

docker_subnet_mask="$(
                      docker network inspect bridge \
                      | jq '.[0].IPAM.Config[0].Subnet' \
                      | tr -d '"' \
                      | cut -f2 -d '/'
)"

handle_packet() {
    packet="$1"
    message="$(echo $packet | cut -f3 -d '|')"

    address="$(
               echo "$packet" \
               | cut -f2 -d '|' \
               | cut -f3 -d ' '
    )"
    address="$address/$docker_subnet_mask"
    if [ "$message" = "DEAD" ]
    then
        echo "Killing user with ip $address" >> $LOG
        container_name="$(    
            docker network inspect bridge \
            | jq \
              '.[0].Containers 
                | map(select(.IPv4Address == "'"$address"'")) 
                | .[0].Name' \
            | tr -d '"'
        )"
        docker rm -f "$container_name"
        echo "killed container $container_name" >> $LOG
    elif [ "$(echo $message | cut -f1 -d ' ')" = "SOLUTION" ]
    then
        submitted_solution="$(echo $message | cut -f3- -d ' ')"
        challenge_no="$(echo $message | cut -f2 -d ' ')"
        correct_solution="$(sed $challenge_no'q;d' solutions.txt)"
        sed_escaped_address="$(echo $address | sed 's/\./\\./g')"

        echo "$address submitted solution for challenge $challenge_no: $submitted_solution" >> $LOG
        if [ "$submitted_solution" = "$correct_solution" ]
        then
            num_correct=""
            echo "Solution was correct!" >> $LOG

            grep -qE "^$address" scoreboard.txt \
                || echo "$address" >> scoreboard.txt

            grep -qE "^$address .*$challenge_no," scoreboard.txt \
                || sed -i "s|$sed_escaped_address|$address $challenge_no,|" scoreboard.txt

            num_correct="$(
                grep -m1 -E "^$address" scoreboard.txt \
                | grep -oE '[0-9],' \
                | wc -l
            )"
            total_solutions="$(cat solutions.txt | wc -l)"
            if [ $num_correct = $total_solutions ]
            then
                echo "$address HAS WON THE GAME!!!" >> $LOG
                sleep 5
                echo "Killing all continers..." >> $LOG
                docker ps -aq --filter label="SLBR User Container" | xargs docker rm -f
                exit
            fi

            echo "$num_correct correct answers so far" >> $LOG
        fi
    fi
}

echo "game server listening on $PORT"
while true
do
    packet=$(nc -w 1 -W 1 -vlp $PORT 2>&1)
    handle_packet "$(echo "$packet" | head -n 3 | tr '\n' '|')" &
done