#!/usr/bin/env bash

# Grasscutter install script for linux - Simpler version
# This installer doesn't ask you to install dependencies, you have to install them manually
# Made by TurtleIdiot and modified by syktyvkar (and then again modified by Blue)

# Stops the installer if any command has a non-zero exit status
set -e

# Checks for root
if [ $EUID != 0 ]; then
    echo "Please run the installer as root (sudo)!"
    exit
fi

is_command() {
    # Checks if given command is available
    local check_command="$1"
    command -v "${check_command}" > /dev/null 2>&1
}

# IP validation
valid_ip() {
    local ip=$1
    local stat=1

    if [[ $ip =~ ^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}$ ]]; then
        OIFS=$IFS
        IFS="."
        ip=($ip)
        IFS=$OIFS
        [[ ${ip[0]} -le 255 && ${ip[1]} -le 255 \
            && ${ip[2]} -le 255 && ${ip[3]} -le 255 ]]
        stat=$?
    fi
    return $stat
}
echo "#################################"
echo ""
echo "This script will take for granted that you have all dependencies installed (mongodb, openjdk-17-jre/jre17-openjdk, wget, openssl, unzip, git, curl, base-devel), in fact, this script is recommended to update your current server installation, and it should run from the same folder as grasscutter.jar"
echo "#################################"
echo ""
echo "If you are using version > 2.8 of the client, make sure to use the patched metadata if you don't use Cultivation."
echo "Search for METADATA here: https://discord.gg/grasscutter."
echo ""
echo "#################################"

echo ""
echo "Grasscutter will be installed to script's running directory"
echo "Do you wish to proceed and install Grasscutter?"
select yn in "Yes" "No" ; do
    case $yn in
        Yes ) break;;
        No )
			echo "Aborting..."
			exit;;
    esac
done

if [ -d "./resources" ]
then
    echo "It's recommended to remove resources folder"
    echo "Remove resources folder?"
    select yn in "Yes" "No" ; do
        case $yn in
            Yes ) 
                rm -rf resources
                break;;
            No )
                echo "Aborting..."
                exit;;
        esac
    done
echo "You may need to remove data folder and config.json to apply some updates"
echo "#################################"
fi



# Allows choice between stable and dev branch
echo "Please select the branch you wish to install"
echo -e "!!NOTE!!: stable is the recommended branch.\nDo *NOT* use development unless you have a reason to and know what you're doing"
select branch in "stable" "development" ; do
    case $branch in
        stable )
            break;;
        development )
            break;;
    esac
done

echo -e "Using $branch branch for installing server \n"

# Prompt IP address for config.json and for generating new keystore.p12 file
echo "Please enter the IP address that will be used to connect to the server"
echo "This can be a local or a public IP address"
echo "This IP address will be used to generate SSL certificates, so it is important it is correct!"

while : ; do
    read -p "Enter server IP: " SERVER_IP
    if valid_ip $SERVER_IP; then
        break;
    else
        echo "Invalid IP address. Try again."
    fi
done

echo "Beginning Grasscutter installation..."


# Download resources
echo "Downloading Grasscutter BinOutputs..."
git clone --single-branch https://github.com/Koko-boya/Grasscutter_Resources.git Grasscutter-bins
mv ./Grasscutter-bins/Resources ./resources
rm -rf Grasscutter-bins # takes ~350M of drive space after moving BinOutputs... :sob:

# Download and build jar
echo "Downloading Grasscutter source code..."
git clone --single-branch -b $branch https://github.com/Grasscutters/Grasscutter.git Grasscutter-src #change this to download a fork

echo "Building grasscutter.jar..."
cd Grasscutter-src
chmod +x ./gradlew #just in case
./gradlew --no-daemon jar
mv $(find -name "grasscutter*.jar" -type f) ../grasscutter.jar
echo "Building grasscutter.jar done!"
cd ..

# Generate handbook/config
echo "Grasscutter will be started to generate its data files"
echo "Please enter language for GM handbook when prompted"
echo "Grasscutter will stop once GM handbook is generated"
java -jar grasscutter.jar -handbook

# Replaces "127.0.0.1" with given IP
echo "Replacing IP address in server config..."
sed -i "s/127.0.0.1/$SERVER_IP/g" config.json

# Generates new keystore.p12 with the server's IP address
# This is done to prevent a "Connection Timed Out" error from appearing
#	   after clicking to enter the door in the main menu/title screen
# This issue only exists when connecting to a server *other* than localhost
#	   since the default keystore.p12 has only been made for localhost

mkdir certs
cd certs
echo "Generating CA key and certificate pair..."
openssl req -x509 -nodes -days 25202 -newkey rsa:2048 -subj "/C=GB/ST=Essex/L=London/O=Grasscutters/OU=Grasscutters/CN=$SERVER_IP" -keyout CAkey.key -out CAcert.crt

echo "Generating SSL key and certificate pair..."
openssl genpkey -out ssl.key -algorithm rsa

# Creates a conf file in order to generate a csr
cat > csr.conf <<EOF
[ req ]
default_bits = 2048
prompt = no
default_md = sha256
req_extensions = req_ext
distinguished_name = dn

[ dn ]
C = GB
ST = Essex
L = London
O = Grasscutters
OU = Grasscutters
CN = $SERVER_IP

[ req_ext ]
subjectAltName = @alt_names

[ alt_names ]
IP.1 = $SERVER_IP
EOF

# Creates csr using key and conf
openssl req -new -key ssl.key -out ssl.csr -config csr.conf

# Creates conf to finalise creation of certificate
cat > cert.conf <<EOF

authorityKeyIdentifier=keyid,issuer
basicConstraints=CA:FALSE
keyUsage = digitalSignature, nonRepudiation, keyEncipherment, keyAgreement, dataEncipherment
subjectAltName = @alt_names

[alt_names]
IP.1 = $SERVER_IP

EOF

# Creates SSL cert
openssl x509 -req -in ssl.csr -CA CAcert.crt -CAkey CAkey.key -CAcreateserial -out ssl.crt -days 25202 -sha256 -extfile cert.conf

echo "Generating keystore.p12 from key and certificate..."
openssl pkcs12 -export -out keystore.p12 -inkey ssl.key -in ssl.crt -certfile CAcert.crt -passout pass:123456

cd ../
mv ./certs/keystore.p12 ./keystore.p12
echo "Done!"

# Running scripts as sudo makes all Grasscutter files to be owned by root
# which may cause problems editing .jsons...
if [ $SUDO_USER ]; then
	echo "Changing Grasscutter files owner to current user..."
	chown -R $SUDO_USER:$SUDO_USER ./*
fi

echo "Asking Noelle to clean up..."
rm -rf ./certs ./Grasscutter-src

echo "All done!"
echo "-=-=-=-=-=--- !! IMPORTANT !! ---=-=-=-=-=-"
echo "Please make sure that ports 80, 443, 8888 and 22102 are OPEN (both tcp and udp)"
echo "In order to run the server, run the following command:"
echo "    sudo java -jar grasscutter.jar"
echo "You must run it using sudo as port 443 is a privileged port"
echo "To play, use the IP you provided earlier ($SERVER_IP) via GrassClipper or Fiddler"

exit