#!/bin/bash

PID=/opt/minecraft/mc.pid

status() {
    screen -S minecraft -X stuff "list
"
    echo
    echo "== Status =="
    ps -p $(cat $PID) -o %cpu,%mem,cmd
    echo
    LAST_STATUS=$(cat logs/latest.log | grep -n "players online:" | tail -n1 | cut -d ":" -f 1)
    tail -n +$LAST_STATUS logs/latest.log
    echo
}

start() {
    if test -f "$PID"; then
        echo "Server already running with pid: $(cat $PID)"
        status
        exit 0
    fi
    screen -S minecraft -dm java -Xms1G -Xmx5G -jar server.jar nogui
    pgrep -P "$(screen -list | sed -E -n 's/\s*([0-9]+).minecraft.*/\1/p')" > $PID
}

stop() {
    if test -f "$PID"; then
        SCREEN_PID=$(screen -list | sed -E -n 's/\s*([0-9]+).minecraft.*/\1/p')
        screen -S minecraft -X stuff "stop
"
        echo -n "Waiting for shutdown..."
        # kill -0 checks if a process is running
        while kill -0 $SCREEN_PID 2> /dev/null; do
            sleep 3
            echo -n "."
        done
        echo " Shutdown Complete!"
        rm $PID
        exit 0
    fi
    echo "No server is running..."
}

case "$1" in
    'start')
        start
        ;;
    'stop')
        stop
        ;;
    'restart')
        stop
        start
        ;;
    'status')
        status
        ;;
    *)
        echo
        echo "Usage: $0 { start | stop | restart | status }"
        echo
        exit 1
        ;;
esac

exit 0