#!/bin/bash
# SpongeForge Installation Script
#
# Server Files: /mnt/server
apt update
apt install -y jq curl

mkdir -p /mnt/server
cd /mnt/server

#Function to Compare Strings in Dot-Separated Version Format (can comapre Versions with unequal lengths)
#returns 1 if version 1 is less than version 2, and 0 if version 1 is greater than version 2
vercomp() {
    if [[ $1 == $2 ]]
    then
        return 1
    fi
    local IFS=.
    local i ver1=($1) ver2=($2)
    # fill empty fields in ver1 with zeros
    for ((i=${#ver1[@]}; i<${#ver2[@]}; i++))
    do
        ver1[i]=0
    done
    for ((i=0; i<${#ver1[@]}; i++))
    do
        if [[ -z ${ver2[i]} ]]
        then
            # fill empty fields in ver2 with zeros
            ver2[i]=0
        fi
        if ((10#${ver1[i]} > 10#${ver2[i]}))
        then
            return 0
        fi
        if ((10#${ver1[i]} < 10#${ver2[i]}))
        then
            return 1
        fi
    done
    return 1
}

# Remove spaces from the version number to avoid issues with curl
FORGE_VERSION="$(echo "$FORGE_VERSION" | tr -d ' ')"

#Adding .jar when not ending by SERVER_JARFILE
if [[ ! ${SERVER_JARFILE} = *\.jar ]]; then
  SERVER_JARFILE="${SERVER_JARFILE}.jar"
fi


if [ -z ${SF_VERSION} ] || [ "$(curl -s https://dl-api.spongepowered.org/v1/org.spongepowered/spongeforge/downloads/${SF_VERSION})" == "Unknown version" ]; then
    echo -e "defaulting to recommended"
    SF_VERSION="recommended"
fi

if [ "${SF_VERSION}" == "recommended" ]; then
    echo -e "using recommended SpongeForge version"
    SF_VERSION=$(curl -s https://dl-api.spongepowered.org/v1/org.spongepowered/spongeforge/downloads/recommended | jq -r '.version')
    echo -e "found SpongeForge Version ${SF_VERSION}"
    SF_DL_LINK=$(curl -s https://dl-api.spongepowered.org/v1/org.spongepowered/spongeforge/downloads/recommended | jq -r '.artifacts."".url')
    FORGE_DOWNLOAD_VERSION=$(curl -s https://dl-api.spongepowered.org/v1/org.spongepowered/spongeforge/downloads/recommended | jq -r '.dependencies.forge')
    echo -e "found Forge Version ${FORGE_DOWNLOAD_VERSION}"
    MC_VERSION=$(curl -s https://dl-api.spongepowered.org/v1/org.spongepowered/spongeforge/downloads/${SF_VERSION} | jq -r '.dependencies.minecraft')
elif [ "${SF_VERSION}" == "latest" ]; then
    echo -e "using latest SpongForge version"
    SF_VERSION=$(curl -s https://dl-api.spongepowered.org/v1/org.spongepowered/spongeforge | jq -r '.buildTypes.stable.latest.version')
    echo -e "found SpongeForge Version ${SF_VERSION}"
    SF_DL_LINK=$(curl -s https://dl-api.spongepowered.org/v1/org.spongepowered/spongeforge/downloads/${SF_VERSION} | jq -r '.artifacts."".url')
    FORGE_DOWNLOAD_VERSION=$(curl -s https://dl-api.spongepowered.org/v1/org.spongepowered/spongeforge/downloads/${SF_VERSION} | jq -r '.dependencies.forge')
    MC_VERSION=$(curl -s https://dl-api.spongepowered.org/v1/org.spongepowered/spongeforge/downloads/${SF_VERSION} | jq -r '.dependencies.minecraft')
else
    echo -e "found SpongeForge Version ${SF_VERSION}"
    SF_DL_LINK=$(curl -s https://dl-api.spongepowered.org/v1/org.spongepowered/spongeforge/downloads/${SF_VERSION} | jq -r '.artifacts."".url')
    FORGE_DOWNLOAD_VERSION=$(curl -s https://dl-api.spongepowered.org/v1/org.spongepowered/spongeforge/downloads/${SF_VERSION} | jq -r '.dependencies.forge')
    echo -e "found Forge Version ${FORGE_DOWNLOAD_VERSION}"
    MC_VERSION=$(curl -s https://dl-api.spongepowered.org/v1/org.spongepowered/spongeforge/downloads/${SF_VERSION} | jq -r '.dependencies.minecraft')
fi

if [[ ! -z ${FORGE_VERSION} ]]; then
    if curl --output /dev/null --silent --head --fail https://maven.minecraftforge.net/net/minecraftforge/forge/${FORGE_VERSION}/forge-${FORGE_VERSION}-installer.jar; then
        echo -e "Custom Forge Version found."
        if [ ${MC_VERSION} != ${FORGE_VERSION%%-*} ]; then
            echo -e "You need Forge Minecraft Version ${MC_VERSION}. Exiting now!"
            exit 1
        elif vercomp ${FORGE_DOWNLOAD_VERSION} ${FORGE_VERSION##*-}; then
            echo -e "Forge Build Version must be greater than ${FORGE_DOWNLOAD_VERSION}. Exiting now!"
            exit 1
        else
            FORGE_DOWNLOAD_VERSION=${FORGE_VERSION##*-}
        fi
    else
        echo -e "Forge Version not found. Check if Version is spelled right. Exiting now!"
        exit 1
    fi
fi

FORGE_DL_LINK=https://maven.minecraftforge.net/net/minecraftforge/forge/${MC_VERSION}-${FORGE_DOWNLOAD_VERSION}/forge-${MC_VERSION}-${FORGE_DOWNLOAD_VERSION}

if [ -f server.jar ] && [ $(sha1sum server.jar | awk '{ print $1 }') == $(curl -s ${FORGE_DL_LINK}-universal.jar.sha1) ]; then
    echo -e "Already have the correct forge version"
else
    echo -e "Downloading forge version ${MC_VERSION} - ${FORGE_DOWNLOAD_VERSION}"
    echo -e "running: curl -s -o installer.jar -o ${FORGE_DL_LINK}-installer.jar"
    curl -s -o installer.jar ${FORGE_DL_LINK}-installer.jar
    echo -e "running: curl -s -o ${SERVER_JARFILE} -o ${FORGE_DL_LINK}-universal.jar"
    curl -s -o ${SERVER_JARFILE} ${FORGE_DL_LINK}-universal.jar
    java -jar installer.jar --installServer
    rm installer.jar forge-${MC_VERSION}-${FORGE_DOWNLOAD_VERSION}-universal.jar forge-${MC_VERSION}-${FORGE_DOWNLOAD_VERSION}.jar
fi

if [ ! -d /mnt/server/mods/ ]; then
    echo -e "making mods directory"
    mkdir -p /mnt/server/mods/
fi

if [ -f /mnt/server/mods/spongeforge*.jar ]; then
    mkdir -p /mnt/server/mods/old/
    mv -f /mnt/server/mods/spongeforge*.jar /mnt/server/mods/old/spongeforge*.jar
fi 

echo -e "running: curl -s ${SF_DL_LINK} -o /mnt/server/mods/spongeforge-${SF_VERSION}.jar"
curl -s ${SF_DL_LINK} -o /mnt/server/mods/spongeforge-${SF_VERSION}.jar

if [ ! -f server.properties ]; then
    echo -e "Downloading MC server.properties"
    curl -o server.properties https://raw.githubusercontent.com/ptero-eggs/game-eggs/main/minecraft/java/server.properties
fi

echo -e "Install for SpongeForge is complete"