#!/bin/bash
# Simple bukkit startup script by Piffey
# This is by no means a clean script, but it will get the job done.
# Suggestions? Improvements? Let me know at Piffey.com

# All of the screen stuff was adapted from ragon's <frederik.engels24 AT gmail DOT com> script for his Arch Linux package.
# Reason: I don't use screen, but it's likely the best option for anyone looking for a simple script they can run and ignore.
# His script worked perfect for my first server too. Thanks ragon.


## 03/27/11 Updates (ryunp)
#    Modified for tmux
#    Altered $dateformat into `_yymmdd-hhmmss` so you get: <world>_yymmdd-hhmmss
#        This allows unique inter-minute backups
#    Invocation variable ($bukkitinvoaction) instead of just RAM allocation
#    Added bukkitstatus() to check offline/online status
#        If online shows process activity/information
#    Updated startbukkit() & stopbukkit() to check java process status after invoked/stopped
#        Added friendlystop timing sequence to the stopbukkit() itself; checks for arg given in case statement
#    updatebukkit() will save current JAR as <JAR>.old and rename newly downloaded file
#    bukkitbackup() added zip + targz support by choosing, added customizable messaged for before/after
#        Added a second backupmsg and completion var, tar & zip integration (if zip is installed; checks before attempting)
#    Added status to argument case statement and catchall display, updated friendlystop
##

# Set these values to match your server's settings.
bukkitdir="~/bukkit/"
backupdir="~/bukkit/backups/"
bukkitfilename="craftbukkit.jar"
bukkitupdate="craftbukkit-updater.jar"

# Will omit backup messages if quotes left empty
backupmsg="Backup in progress. Saving disabled for a moment."
backupmsgdone="Level data successfully backed up!"

dateformat="_$(date '+%y%m%d-%H%M%S')"

# Determine additional archived level backups
# Note: `zip` format is not native to most (all?) linux distro's, must install to work.
backuplevelzip="true"
backuplevelgz="false"

# Custom java binary location. Do not change unless custom installation was done, ex: `/opt/java/bin/java`.
# This assumes java is in the default location: /usr/bin/java.
javaloc="java"

# Invocation parameters. Set the amount of RAM you want to allocate, Java heap max and initial size.
# Good practice is to have the numbers match.
bukkitinvocation="$javaloc -Xmx2048M -Xms2048M -jar '$bukkitdir$bukkitfilename' nogui"

# Make sure you change this to the name of your world folder!
# Add additional worlds by separating them with a white space, ex: =(world nether pvp chaos).
declare -a worlds=(world)
numworlds=${#worlds[@]}

# This currently points to the "preferred" release for bukkit which is kind of like a stable version.
# Change this value if you want to use the snapshot release.
bukkiturl=http://ci.bukkit.org/job/dev-CraftBukkit/promotion/latest/Recommended/artifact/target/craftbukkit-0.0.1-SNAPSHOT.jar

bukkitstatus()
{
    if ! ps ax | grep -v grep | grep -v -i tmux | grep "$bukkitfilename" > /dev/null; then
       echo "Bukkit server currently OFFLINE"
       exit 0
    else
       echo "Bukkit server currently ONLINE:"

       # Get the Process ID of running JAR file
       bukkitPID=`ps ax | grep -v grep | grep -v -i tmux | grep -v sh | grep "$bukkitfilename"`

       # Display process activity information of bukkit (5 character length pID)
       top -n 1 -p ${bukkitPID:0:5} | grep ${bukkitPID:0:5}

       # Display prcoess infomation of bukkit
       echo "$bukkitPID"
    fi
}
startbukkit()
{
    if ! ps ax | grep -v grep | grep -v -i tmux | grep "$bukkitfilename" > /dev/null; then
        echo "Starting Bukkit server..."
        cd $bukkitdir

        # Check for a tmux minecraft session already active; if so create a new window within, otherwise new session
        # (Creating a new window in a minecraft tmux session will cause the session to stay active even after this scripts stopbukkit function is called)
        if ! tmux ls | grep minecraft > /dev/null; then
            tmux new -d -n bukkit -s minecraft "$bukkitinvocation"
        else
            echo "tmux minecraft sessions detected: creating window within!"
            tmux neww -d -n bukkit -t minecraft "$bukkitinvocation"
        fi

        # Check for process status, wait 7 seconds for plugin initialization
        sleep 7
        if ! ps ax | grep -v grep | grep -v -i tmux | grep "$bukkitfilename" > /dev/null; then
            echo "Bukkit server failed to start!"
        else
            echo "Bukkit server successfully started!"
        fi
    else
        echo "Bukkit server is already running."
        exit 0
    fi
}

stopbukkit()
{
    if ! ps ax | grep -v grep | grep -v -i tmux | grep "$bukkitfilename" > /dev/null; then
        echo "Bukkit server is not running."
        exit 0
    else
        # Check for friendlystop trigger
        if [ "$1" == "friendly" ]; then
            echo "Sending 5 minute shutown warning"
            tmux send -t minecraft:bukkit "say Going down in 5 minutes." C-m
            sleep 240
            echo "Sending 1 minute shutdown warning"
            tmux send -t minecraft:bukkit "say Going down in 60 seconds." C-m
            sleep 30
            echo "Sending 30 second shutdown warning"
            tmux send -t minecraft:bukkit "say Going down in 30 seconds." C-m
            sleep 25
            echo "Sending 5 second shutdown warning"
            tmux send -t minecraft:bukkit "say Going down in 5 seconds." C-m
            sleep 5
        fi

        tmux send -t minecraft:bukkit 'stop' C-m

        # Check for process status, waiting 5 seconds for shutdown procedure to finish
        sleep 5
        if ! ps ax | grep -v grep | grep -v -i tmux | grep "$bukkitfilename" > /dev/null; then
            echo "Bukkit server successfully stopped!"
        else
            echo "Process failed to stop!"

            # Take more aggresive action against pID
            echo "Attempting to kill rogue $bukkitfilename process..."

            # Get the Process ID of running JAR file
            bukkitPID=`ps ax | grep -v grep | grep -v -i tmux | grep -v sh | grep "$bukkitfilename"`
            kill ${bukkitPID:0:5}
            sleep 1

            # Check for process status after pkill attempt
            if ! ps ax | grep -v grep | grep -v -i tmux | grep "$bukkitfilename" > /dev/null; then
                echo "$bukkitfilename process terminated!"
            else
                echo "$bukkitfilename could not be killed!"
                exit 1
            fi
        fi
    fi
}

updatebukkit()
{
    # Alert players Bukkit server going down for repairs
    if ps ax | grep -v grep | grep -v -i tmux | grep "$bukkitfilename" > /dev/null; then
        tmux send -t minecraft:bukkit "say Going down for an update in 60 seconds." C-m
        sleep 5
        tmux send -t minecraft:bukkit "say Going down for an update in 5 seconds." C-m
        sleep 5
        stopbukkit
    fi

    # Download new JAR
    wget -O "$bukkitdir$bukkitupdate" "$bukkiturl"
    sleep 1

    # Backup old JAR file and rename newly downloaded
    mv -v "$bukkitdir$bukkitfilename" "$bukkitdir$bukkitfilename.old"
    mv -v "$bukkitdir$bukkitupdate" "$bukkitdir$bukkitfilename"
    echo "You must now manually start the Bukkit server."
}

backupbukkit()
{
    echo "Starting multiworld backup..."
    # Alert players backup is in progress
    if ! ps ax | grep -v grep | grep -v -i tmux | grep "$bukkitfilename" > /dev/null; then
        echo "Bukkit server not running!"
    else
        if [ "$backupmsg" != "" ]; then tmux send -t minecraft:bukkit "say $backupmsg" C-m; fi
        if [ "$backupmsg2" != "" ]; then tmux send -t minecraft:bukkit "say $backupmsg2" C-m; fi
        tmux send -t minecraft:bukkit "save-all" C-m
        sleep 5
        tmux send -t minecraft:bukkit "save-off" C-m
    fi

    # Check for backup directory
    if ! [ -d $backupdir ];then mkdir -p $backupdir; fi

    # Determine if zip package is installed on host
    if ! dpkg-query -W 'zip' > /dev/null; then backuplevelzip="false"; fi

    # Iterate through level backups
    cd $backupdir
    for ((i=0;i<$numworlds;i++)); do
        echo "Copying '${worlds[$i]}' + '$bukkitfilename' to '$backupdir${worlds[$i]}$dateformat'..."
        cp -R $bukkitdir${worlds[$i]} $backupdir${worlds[$i]}$dateformat
        cp $bukkitdir$bukkitfilename $backupdir${worlds[$i]}$dateformat

        # TARgz backup sequence
        if [ "$backuplevelgz" == "true" ]; then
            echo "Creating tar archive file of '${worlds[$i]}$dateformat'..."
            tar zcf ${worlds[$i]}$dateformat.tar.gz ${worlds[$i]}$dateformat/
        fi

        # ZIP backup sequence
        if [ "$backuplevelzip" == "true" ]; then
             echo "Creating zip archive file of '${worlds[$i]}$dateformat'..."
             zip -rq ${worlds[$i]}$dateformat ${worlds[$i]}$dateformat
        fi
    done
    sleep 1

    # Alert players backup is finished
    if ps ax | grep -v grep | grep -v -i tmux | grep "$bukkitfilename" > /dev/null; then
        tmux send -t minecraft:bukkit "save-on" C-m
        if [ "$backupmsgdone" != "" ]; then tmux send -t minecraft:bukkit "say $backupmsgdone" C-m; fi
    fi
    echo "Backup complete."
}

case $1 in
    status)
        bukkitstatus
        ;;
    start)
        startbukkit
        ;;
    stop)
        stopbukkit
        ;;
    restart)
        stopbukkit
        sleep 5
        startbukkit
        ;;
    update)
        updatebukkit
        ;;
    backup)
        backupbukkit
        ;;
    friendlystop)
        stopbukkit friendly
        ;;
    *)
        echo "Usage: $0 {status|start|stop|restart|update|backup|friendlystop}"
esac

exit 0