#!/bin/sh

# Check syntax
if [ $# -lt 1 ]
then
    echo "Usage: ./changeversion <server version>. Server version must match file name of a server jar minus the '.jar'."
    echo "Example: ./changeversion b1.7.3"
    echo "To see what versions are available, check the contents of the 'versions' folder"
    exit 0
fi

# Check server jar exists
echo "\n\n\nStarting changeversion..."
echo "By using this software, you agree to sell your soul to the zucc. No takebacks.\n\n\n"
version=$1
filename="$version.jar"
if [ ! -f "./versions/$filename" ]
then
    echo "No server jar exists for version $1"
    echo "To see what versions are available, check the contents of the 'versions' folder"
    exit 0
fi

echo "Stopping Minecraft server..."
# Stop minecraft server if it hasn't yet
service minecraft stop
sleep 3 # wait for it to stop

# Create new server directory for specified version if doesn't exist
new_server_dir="./versions/$version"
template_location="./config-templates"
if [ ! -d $new_server_dir ]
then
    echo "No previous directory for $version detected. Creating new directory"
    mkdir $new_server_dir
    cp "./versions/$filename" "$new_server_dir/minecraft_server.jar" # server jar
    cp "$template_location/server.properties" $new_server_dir
    cp "$template_location/eula.txt" $new_server_dir
    cp "$template_location/minecraft_service.sh" $new_server_dir
    cp "$template_location/minecraft_server.sh" $new_server_dir
fi

# Move current server to storage
minecraft_directory="/home/minecraft"
version_file="$minecraft_directory/version"
if [ ! -f $version_file ]
then # If version unknown, move to unknown-version directory
    unknown_version_dir="`pwd`/unknown-version"
    echo "Could not detect server version (/home/minecraft/version) file missing."
    echo "Will move files in /home/minecraft to $unknown_version_dir"

    if [ -d $unknown_version_dir ]
    then
        rm -r $unknown_version_dir
    fi
    mkdir $unknown_version_dir
    mv $minecraft_directory/* $unknown_version_dir

else # Else move files to relevant directory
    old_version=`cat $version_file`
    if [ $old_version = $version ]
    then
        echo "You're already on version $version! Exiting..."
        exit 0
    fi

    old_server_dir="./versions/$old_version"
    if [ -d $old_server_dir ]
    then
        rm -r $old_server_dir
    fi
    mkdir $old_server_dir
    mv $minecraft_directory/* $old_server_dir
fi

# Move new server to $minecraft_directory
mv $new_server_dir/* $minecraft_directory

# Set file ownership in case it hasn't been done yet
chown -R minecraft $minecraft_directory
chgrp -R minecraft $minecraft_directory

# Just in case it got deleted, write out the version file so we can re-identify it later on
echo "$version" > $minecraft_directory/version

echo "Server switched to version $version. Start the server again with 'service minecraft start'"