#!/bin/bash
# Copyright (c) 2026 fithwum
# All rights reserved

DEBIAN_VERSION=13

MC_DIR=/mcserver

EULA_FILE=$MC_DIR/eula.txt
EULA_MARKER=$MC_DIR/.eula_accepted
INSTALLED_VERSION=$MC_DIR/installed-$TARGET_VERSION

SERVER_PROPERTIES=https://gitea.fithwum.tech/fithwum/minecraft/raw/branch/master/testing/server.properties
START_FILE=https://gitea.fithwum.tech/fithwum/minecraft/raw/branch/master/testing/start.sh

RUN_VANILLA=https://gitea.fithwum.tech/fithwum/minecraft/raw/branch/master/testing/run-vanilla.sh
RUN_BUKKIT=https://gitea.fithwum.tech/fithwum/minecraft/raw/branch/master/testing/run-bukkit.sh
RUN_FABRIC=https://gitea.fithwum.tech/fithwum/minecraft/raw/branch/master/testing/run-fabric.sh
RUN_QUILT=https://gitea.fithwum.tech/fithwum/minecraft/raw/branch/master/testing/run-quilt.sh

BUKKIT_INSTALLER_FILE=https://cdn.getbukkit.org/craftbukkit/craftbukkit-$MC_VERSION.jar
FABRIC_SERVER_FILE=https://meta.fabricmc.net/v2/versions/loader/$MC_VERSION/$FABRIC_VERSION/$FABRIC_INSTALLER_VERSION/server/jar
QUILT_INSTALLER_FILE=https://quiltmc.org/api/v1/download-latest-installer/java-universal
FORGE_INSTALLER_FILE=https://maven.minecraftforge.net/net/minecraftforge/forge/$MC_VERSION-$FORGE_VERSION/forge-$MC_VERSION-$FORGE_VERSION-installer.jar
NEOFORGED_INSTALLER_FILE=https://maven.neoforged.net/releases/net/neoforged/neoforge/$NEOFORGED_VERSION/neoforge-$NEOFORGED_VERSION-installer.jar

# Install java
if [ $JAVA_VERSION = "openjdk-21-jre" ]; then
    echo "INFO ! $JAVA_VERSION Selected"
	if [ dpkg -s openjdk-21-jre-headless &> /dev/null ]
		then
			echo "INFO ! $JAVA_VERSION installed ... moving on."
		else
			echo " "
			echo "WARNING ! $JAVA_VERSION not installed ... will install now."
			apt-get update
			apt-get --no-install-recommends -y install openjdk-21-jre-headless
	fi
elif [ $JAVA_VERSION = "openjdk-25-jre" ]; then
    echo "INFO ! $JAVA_VERSION Selected"
	if [ dpkg -s openjdk-25-jre-headless &> /dev/null ]
		then
			echo "INFO ! $JAVA_VERSION installed ... moving on."
		else
			echo " "
			echo "WARNING ! $JAVA_VERSION not installed ... will install now."
			apt-get update
			apt-get --no-install-recommends -y install openjdk-25-jre-headless
	fi
else
	echo "ERROR ! Java version must be set first run"
	sleep infinity
fi

# Main install (Debian).
# Check for server files and download if needed.
if [ $MC_TYPE = "vanilla" ]; then
    echo "INFO ! Vanilla Selected"
	# Fallback to default channel type if MC_TYPE or MC_VERSION is empty
	: "${MC_VERSION:=latest}"
	echo "Using server type: $MC_TYPE"

	# Get the currently installed Minecraft version from the filesystem
	CUR_VERSION=$(find "$MC_DIR" -name "installed-*" | cut -d - -f2-)
	echo "Current local version: '${CUR_VERSION:-None}'"

	# Fetch the global Minecraft version manifest cleanly
	JSON=$(curl -s "https://piston-meta.mojang.com/mc/game/version_manifest_v2.json")
	# Validate that we actually received valid JSON
	if [ -z "$JSON" ] || ! echo "$JSON" | jq . >/dev/null 2>&1; then
		echo "Error: Failed to fetch valid JSON from Mojang API"
		exit 1
	fi

	# Resolve the target version dynamically
	if [ ! -z "$MC_VERSION" ] && [ "$MC_VERSION" != "latest" ]; then
		# User specified an exact version string (e.g., 1.20.1)
		TARGET_VERSION=$(echo "$JSON" | jq -r --arg version "$MC_VERSION" '.versions[] | select(.id == $version) | .id')
		if [ -z "$TARGET_VERSION" ]; then
			echo "Error: Specified version '$MC_VERSION' not found in Mojang API."
			exit 1
		fi
	else
		# No version specified or "latest" chosen. Pull from the latest release
		TARGET_VERSION=$(echo "$JSON" | jq -r '.latest.release')
	fi
	echo "Target version determined: '$TARGET_VERSION'"
	# Update variable to match resolved target
	MC_VERSION=$TARGET_VERSION

	# Compare versions and only update if they do NOT match
	if [ "$CUR_VERSION" != "$TARGET_VERSION" ]; then
		echo "Versions differ ($CUR_VERSION vs $TARGET_VERSION). Fetching Minecraft server download URL..."
		# Extract the target sub-manifest URL for this specific Minecraft version
		VERSION_CHECK=$(echo "$JSON" | jq -r --arg version "$TARGET_VERSION" '.versions[] | select(.id == $version) | .url')
		if [ "$VERSION_CHECK" == "null" ] || [ -z "$VERSION_CHECK" ]; then
			echo "Error: Metadata URL link not found for version $TARGET_VERSION"
			exit 1
		fi
		# Fetch the specific version's metadata JSON and extract the server jar link
		MC_SERVER_FILE=$(curl -s "$VERSION_CHECK" | jq -r '.downloads.server.url')
		if [ "$MC_SERVER_FILE" == "null" ] || [ -z "$MC_SERVER_FILE" ]; then
			echo "Error: Server jar download URL not found for version $TARGET_VERSION"
			exit 1
		fi
		echo "Ready to download: $MC_SERVER_FILE"
		# Process Vanilla Minecraft downloads
		echo " "
		echo "WARNING ! Minecraft server is out of date/missing ... will download now."
		echo "INFO ! Cleaning old files."
		cd "$MC_DIR" || exit 1
		mkdir -pv old-server-versions/
		# Wipe old dependencies cleanly
		rm -fr *.jar libraries defaultconfigs user_jvm_args.txt run.bat
		# Safely preserve old logs
		[ -f *.log ] && mv *.log old-server-versions/
		# Download and fix execution modes
		wget --no-cache --show-progress --progress=bar:force:noscroll "$MC_SERVER_FILE" -O "mcserver-$MC_VERSION.jar"
		chmod +x "mcserver-$MC_VERSION.jar"
		echo " "
		echo "WARNING ! run-$MC_TYPE-$MC_VERSION.sh is out of date/missing ... will download now."
		[ -f run-*.sh ] && mv -v run-*.sh old-server-versions/
		wget --no-cache --show-progress --progress=bar:force:noscroll "$RUN_VANILLA" -O "run-$MC_TYPE-$MC_VERSION.sh"
		chmod +x "run-$MC_TYPE-$MC_VERSION.sh"
		# Drop updated marker file
		rm -f installed-*
		touch installed-$MC_VERSION
		cd ..
	else
		echo "No update required. Local version matches target version."
	fi
elif [ $MC_TYPE = "bukkit" ]; then
    echo "INFO ! Bukkit Selected"
	if [ -e $MC_DIR/craftbukkit-$MC_VERSION.jar ]
		then
			echo " "
			echo "INFO ! craftbukkit-$MC_VERSION.jar found starting now."
		else
			echo " "
			echo "WARNING ! craftbukkit-$MC_VERSION.jar is out of date/missing ... will download now."
			echo " "
			echo "INFO ! Cleaning old files."
			cd $MC_DIR
			mkdir -pv old-server-versions/
			rm -fr *.jar libraries defaultconfigs config mods user_jvm_args.txt run.bat
			mv -v *.log old-server-versions/
			wget --no-cache --show-progress --progress=bar:force:noscroll $BUKKIT_INSTALLER_FILE -O craftbukkit-$MC_VERSION.jar
			chmod +x craftbukkit-$MC_VERSION.jar
			echo " "
			echo "WARNING ! run-$MC_TYPE-$MC_VERSION.sh is out of date/missing ... will generate now."
			mv -v run-*.sh old-server-versions/
			wget --no-cache --show-progress --progress=bar:force:noscroll $RUN_BUKKIT -O run-$MC_TYPE-$MC_VERSION.sh
			chmod +x run-$MC_TYPE-$MC_VERSION.sh
			cd ..
	fi
elif [ $MC_TYPE = "fabric" ]; then
    echo "INFO ! Fabric Selected"
	if [ -e $MC_DIR/fabric-$MC_VERSION-$FABRIC_VERSION.jar ]
		then
			echo " "
			echo "INFO ! fabric-$MC_VERSION-$FABRIC_VERSION.jar found starting now."
		else
			echo " "
			echo "WARNING ! fabric-$MC_VERSION-$FABRIC_VERSION.jar is out of date/missing ... will download now."
			echo " "
			echo "INFO ! Cleaning old files."
			cd $MC_DIR
			mkdir -pv old-server-versions/
			rm -fr *.jar libraries defaultconfigs config mods user_jvm_args.txt run.bat
			mv -v *.log old-server-versions/
			wget --no-cache --show-progress --progress=bar:force:noscroll $FABRIC_SERVER_FILE -O fabric-$MC_VERSION-$FABRIC_VERSION.jar
			chmod +x fabric-$MC_VERSION-$FABRIC_VERSION.jar
			echo " "
			echo "WARNING ! run-$MC_TYPE-$MC_VERSION.sh is out of date/missing ... will generate now."
			mv -v run-*.sh old-server-versions/
			wget --no-cache --show-progress --progress=bar:force:noscroll $RUN_FABRIC -O run-$MC_TYPE-$MC_VERSION.sh
			chmod +x run-$MC_TYPE-$MC_VERSION.sh
			cd ..
	fi
elif [ $MC_TYPE = "quilt" ]; then
    echo "INFO ! Quilt Selected"
	if [ -e $MC_DIR/quilt-installer-$QUILT_VERSION.jar ]
		then
			echo " "
			echo "INFO ! quilt-installer-$QUILT_VERSION.jar found starting now."
		else
			echo " "
			echo "WARNING ! quilt-installer-$QUILT_VERSION.jar is out of date/missing ... will download now."
			echo " "
			echo "INFO ! Cleaning old files."
			cd $MC_DIR
			mkdir -pv old-server-versions/
			rm -fr *.jar libraries defaultconfigs config mods user_jvm_args.txt run.bat
			mv -v *.log old-server-versions/
			wget --no-cache --show-progress --progress=bar:force:noscroll $QUILT_INSTALLER_FILE -O quilt-installer-$QUILT_VERSION.jar
			chmod +x quilt-installer-$QUILT_VERSION.jar
			java -jar quilt-installer-$QUILT_VERSION.jar install server $MC_VERSION --download-server
			cd server
			mv -v * $MC_DIR
			cd ..
			rm -fr server
			echo " "
			echo "WARNING ! run-$MC_TYPE-$MC_VERSION.sh is out of date/missing ... will generate now."
			mv -v run-*.sh old-server-versions/
			wget --no-cache --show-progress --progress=bar:force:noscroll $RUN_QUILT -O run-$MC_TYPE-$MC_VERSION.sh
			chmod +x run-$MC_TYPE-$MC_VERSION.sh
			cd ..
	fi
elif [ $MC_TYPE = "forge" ]; then
    echo "INFO ! Forge Selected"
	if [ -e $MC_DIR/forge-$MC_VERSION-$FORGE_VERSION-installer.jar ]
		then
			echo " "
			echo "INFO ! forge-$MC_VERSION-$FORGE_VERSION-installer.jar found starting now."
		else
			echo " "
			echo "WARNING ! forge-$MC_VERSION-$FORGE_VERSION-installer.jar is out of date/missing ... will download now."
			echo " "
			echo "INFO ! Cleaning old files."
			cd $MC_DIR
			mkdir -pv old-server-versions/
			rm -fr *.jar libraries defaultconfigs config mods user_jvm_args.txt run.bat
			mv -v *.log old-server-versions/
			mv -v run-*.sh old-server-versions/
			wget --no-cache --show-progress --progress=bar:force:noscroll $FORGE_INSTALLER_FILE -O forge-$MC_VERSION-$FORGE_VERSION-installer.jar
			chmod +x forge-$MC_VERSION-$FORGE_VERSION-installer.jar
			java -jar forge-$MC_VERSION-$FORGE_VERSION-installer.jar --installServer
			mv -v run.sh run-$MC_TYPE-$MC_VERSION.sh
			chmod +x run-$MC_TYPE-$MC_VERSION.sh
			tee user_jvm_args.txt <<-EOF
			-Xmx${XMX_SIZE}
			-Xms${XMS_SIZE}
			-Xmn${XMN_SIZE}
			EOF
			cd ..
	fi
elif [ $MC_TYPE = "neoforged" ]; then
    echo "INFO ! Neoforged Selected"
	if [ -e $MC_DIR/neoforge-$NEOFORGED_VERSION-installer.jar ]
		then
			echo " "
			echo "INFO ! neoforge-$NEOFORGED_VERSION-installer.jar found starting now."
		else
			echo " "
			echo "WARNING ! neoforge-$NEOFORGED_VERSION-installer.jar is out of date/missing ... will download now."
			echo " "
			echo "INFO ! Cleaning old files."
			cd $MC_DIR
			mkdir -pv old-server-versions/
			rm -fr *.jar libraries defaultconfigs config mods user_jvm_args.txt run.bat
			mv -v *.log old-server-versions/
			mv -v run-*.sh old-server-versions/
			wget --no-cache --show-progress --progress=bar:force:noscroll $NEOFORGED_INSTALLER_FILE -O neoforge-$NEOFORGED_VERSION-installer.jar
			chmod +x neoforge-$NEOFORGED_VERSION-installer.jar
			java -jar neoforge-$NEOFORGED_VERSION-installer.jar --installServer
			mv -v run.sh run-$MC_TYPE-$MC_VERSION.sh
			chmod +x run-$MC_TYPE-$MC_VERSION.sh
			tee user_jvm_args.txt <<-EOF
			-Xmx${XMX_SIZE}
			-Xms${XMS_SIZE}
			-Xmn${XMN_SIZE}
			EOF
			cd ..
	fi
else
    echo "ERROR ! MC_TYPE must be set first run"
    sleep infinity
fi

if [ -f $MC_DIR/server.properties ]; then
    echo "INFO ! server.properties found ... moving on."
else
	echo "WARNING ! server.properties missing ... downloading default file."
    wget --no-cache --show-progress --progress=bar:force:noscroll $SERVER_PROPERTIES -O $MC_DIR/server.properties
fi

echo "INFO ! Setting RCON settings."
if [ -f $MC_DIR/server.properties ]; then
	sed -i '/enable-rcon='*'/c\enable-rcon='$ENABLE_RCON'' $MC_DIR/server.properties
	sed -i '/rcon.port='*'/c\rcon.port='$RCON_PORT'' $MC_DIR/server.properties
	sed -i '/rcon.password='*'/c\rcon.password='$RCON_PASSWORD'' $MC_DIR/server.properties
fi

echo "INFO ! Setting game port."
if [ -f $MC_DIR/server.properties ]; then
	sed -i '/server-port='*'/c\server-port='$GAME_PORT'' $MC_DIR/server.properties
fi

# Wait briefly for installer/server to generate eula.txt
if [ ! -f "$EULA_FILE" ] && [ ! -f "$EULA_MARKER" ]; then
    echo "INFO ! Waiting for EULA generation..."
    sleep 5
fi

# If EULA already accepted once, never touch it again
if [ -f "$EULA_MARKER" ]; then
    echo "INFO ! EULA previously accepted"
    return 0 2>/dev/null || true
fi

# First-time decision
if [ "$ACCEPT_EULA" = "true" ]; then
    echo "INFO ! Accepting EULA (one-time)"
    sed -i 's/eula=false/eula=true/' "$EULA_FILE" 2>/dev/null \
    || echo "eula=true" > "$EULA_FILE"
    touch "$EULA_MARKER"
elif [ "$ACCEPT_EULA" = "false" ]; then
    echo "WARNING ! EULA not accepted on first run"
    echo "WARNING ! Set ACCEPT_EULA=true to proceed"
    sleep infinity
else
    echo "ERROR ! ACCEPT_EULA must be set to true or false on first run"
    sleep infinity
fi

# Download the start file for the screen session
if [ -f $MC_DIR/start.sh ]; then
    echo "INFO ! start.sh found ... moving on."
else
	echo "WARNING ! start.sh missing ... downloading default file."
    wget --no-cache --show-progress --progress=bar:force:noscroll $START_FILE -O $MC_DIR/start.sh
	chmod +x $MC_DIR/start.sh
fi

# Set permissions.
chown 99:100 -R $MC_DIR
chmod 776 -R $MC_DIR

sleep 1

# Run Minecraft server.
echo " "
echo "INFO ! Starting Minecraft Server $MC_TYPE-$MC_VERSION"
cd $MC_DIR
exec ./start.sh

exit