#!/usr/bin/env bash

VERSION="0.3.8"

# --- Globals ---

RED='\033[0;31m'
GREEN='\033[0;32m'
ORANGE='\033[0;33m'
NC='\033[0m'

MODS_DIR=""
DB_FILE=""
MODPACKS_FOLDER=""
MODPACKS_DB_FILE=""

H2PATH="${HOME}/.config/h2mm/h2path"
LAST_CHECKED_UPDATE_FILE="${HOME}/.config/h2mm/last_update"
VERSION_URL="https://raw.githubusercontent.com/v4n00/h2mm-cli/refs/heads/master/version"

# --- Utility Functions ---

function get_version_major() {
	echo "$1" | awk -F. '{print $2}'
}

function get_filename_without_path() {
	echo "$1" | awk -F/ '{print $NF}'
}

function get_basename() {
	get_filename_without_path "$1" | sed -E 's/\.+.*//'
}

function get_extension() {
	get_filename_without_path "$1" | sed -E 's/.*patch_[0-9]+//'
}

function get_files_by_entry_from_db() {
	echo "$1" | cut -d',' -f4- | tr ',' ' ' | head -1
}

function disable_all_modpacks() {
	sed -i 's/ENABLED/DISABLED/' "$MODPACKS_DB_FILE"
}

function remove_disabled_prefix() {
	local _file="$1"
	while [[ "$_file" == disabled_* ]]; do
		_file=$(echo "$_file" | sed 's/^disabled_//')
	done
	echo "$_file"
}

function get_mod_name_and_index() {
	if [[ -n "$mod_index" ]]; then # if mod index exists
		entry=$(grep "^${mod_index}," "$DB_FILE")
		mod_name=$(echo "$entry" | awk -F, '{print $3}')
	elif [[ -n "$mod_name" ]]; then # if mod name exists
		entry=$(grep ",$mod_name," "$DB_FILE")
		mod_index=$(echo "$entry" | awk -F, '{print $1}' | head -1)
	fi

	if [[ -z "$entry" || -z "$mod_index" || -z "$mod_name" ]]; then
		if [[ "$1" == "--do-not-exit" ]]; then
			mod_index=-1
		else
			echo -e "${RED}Error${NC}: Mod not found." >&2
			exit 1
		fi
	fi

	status=$(echo "$entry" | awk -F, '{print $2}')
}

function get_modpack_name_and_index() {
	if [[ -n "$modpack_index" ]]; then # if modpack index exists
		entry=$(grep "^${modpack_index}," "$MODPACKS_DB_FILE")
		modpack_name=$(echo "$entry" | awk -F, '{print $3}')
	elif [[ -n "$modpack_name" ]]; then # if modpack name exists
		entry=$(grep ",$modpack_name$" "$MODPACKS_DB_FILE")
		modpack_index=$(echo "$entry" | awk -F, '{print $1}' | head -1)
	fi

	if [[ -z "$entry" || -z "$modpack_index" || -z "$modpack_name" ]]; then
		echo -e "${RED}Error${NC}: Modpack not found." >&2
		exit 1
	fi
}

function find_game_directory() {
	local search_dir="${HOME}"
	local target_dir="Steam/steamapps/common/Helldivers\ 2/data"

	# check if path is saved
	if [[ -f "$H2PATH" ]]; then
		saved_dir=$(cat "$H2PATH")
		if [[ -d "$saved_dir" ]]; then
			echo "$saved_dir"
			return
		else
			echo -e "${RED}Error${NC}: Saved game directory is invalid. Proceeding to get a new directory." >&2
		fi
	fi

	# first time setup, or directory is not valid anymore
	echo "Searching for the Helldivers 2 data directory... (20 seconds timeout)" >&2
	game_dir=$(timeout 20 find "$search_dir" -type d -path "*/$target_dir" 2>/dev/null | head -n 1)

	if [[ -z "$game_dir" ]]; then
		echo "Could not find the Helldivers 2 data directory automatically." >&2
		echo -ne "Please enter the path to the Helldivers 2 data directory:" >&2
		IFS= read -e game_dir
		game_dir="$(realpath "${game_dir/#\~/$HOME}")"

		[[ ! -d "$game_dir" ]] && { echo -e "${RED}Error${NC}: Provided path is not a valid directory." >&2; exit 1; }
	fi

	# save path
	mkdir -p "$(dirname "$H2PATH")"
	echo "$game_dir" > "$H2PATH"

	[[ $? -ne 0 ]] && { echo -e "${RED}Error${NC}: Could not save game directory." >&2; exit 1; }
	echo -e "Game directory ${GREEN}saved${NC}: $game_dir" >&2

	# return the directory
	echo "$game_dir"
}

function initialize_directories() {
	MODS_DIR=$(find_game_directory)
	DB_FILE="$MODS_DIR/mods.csv"

	if [[ ! -f "$DB_FILE" ]]; then
		touch "$DB_FILE"

		[[ $? -ne 0 ]] && { echo -e "${RED}Error${NC}: Could not create database file." >&2; exit 1; }

		echo "$VERSION" | awk -F. '{print $2}' > "$DB_FILE"
		echo -e "Database file ${GREEN}created${NC}: $DB_FILE" &>2
	fi
}

function initialize_modpack_directories() {
	MODPACKS_FOLDER="$MODS_DIR/modpacks"
	MODPACKS_DB_FILE="$MODPACKS_FOLDER/modpacks.csv"

	if [[ ! -d "$MODPACKS_FOLDER" || ! -f "$MODPACKS_DB_FILE" ]]; then
		mkdir -p "$MODPACKS_FOLDER" && touch "$MODPACKS_DB_FILE"

		[[ $? -ne 0 ]] && { echo -e "${RED}Error${NC}: Could not create modpacks folder/file." >&2; exit 1; }
		echo "$VERSION" | awk -F. '{print $2}' > "$MODPACKS_DB_FILE"
		echo -e "Modpacks folder and file ${GREEN}created${NC}: $MODPACKS_FOLDER" &>2
	fi
}

# --- Help Functions ---

function display_help() {
	echo "Helldivers 2 Mod Manager v${VERSION}"
	echo "Usage: h2mm [command] [options]"
	echo "Commands:"
	echo "	i, install					Install a mod by the file provided (directory, zip, patch)."
	echo "	u, uninstall					Uninstall a mod by name (or index)."
	echo "	l, list						List all installed mods."
	echo "	e, enable					Enable a mod by name (or index)."
	echo "	d, disable					Disable a mod by name (or index)."
	echo "	ex, export					Export installed mods to a zip file."
	echo "	im, import					Import mods from a zip file."
	echo "	mc, modpack-create				Create a modpack from the currently installed mods."
	echo "	ms, modpack-switch				Switch to a modpack by name (or index)."
	echo "	ml, modpack-list				List all installed modpacks."
	echo "	mc, modpack-delete				Delete a modpack by name (or index)."
	echo "	mo, modpack-overwrite				Overwrite a modpack by name (or index)."
	echo "	mr, modpack-reset				Reset all installed modpacks."
	echo "	up, update					Update h2mm to the latest version."
	echo "	r, reset					Reset all installed mods."
	echo "	help						Display this help message."
	echo "For more information on usage, use h2mm [command] --help."
	echo "Basic Usage:"
	echo "	h2mm install /path/to/mod.zip"
	echo "	h2mm install /path/to/mod/files"
	echo "	h2mm uninstall \"Example mod\""
}

function display_install_help() {
	echo "Usage: h2mm install [options] <mod_files|mod_dirs|mod_zips>"
	echo "Short form: h2mm i"
	echo "Options:"
	echo "	-n \"<mod_name>\"		Name the mod yourself, inside double quotes."
	echo "	<mod_files>		Multiple mod files, accepts wildcards."
	echo "	<mod_dirs>		Directory/directories containing mod files."
	echo "	<mod_zips>		Zip file(s) containing mod files."
	echo "Usage:"
	echo "	h2mm install /path/to/mod.zip"
	echo "	h2mm install /path/to/mod/files"
	echo "	h2mm install /path/to/mod.zip /path/to/mod2.zip /path/to/mod/files"
	echo "	h2mm install -n \"Example mod\" mod.patch_0 mod.patch_0.stream # -n is mandatory when using files"
	echo "	h2mm install -n \"Example mod\" mod* # using a wildcard to include all files"
	echo "If the mod has more than 1 variant, you need to install the one you want by unarchiving it separately."
}

function display_uninstall_help() {
	echo "Usage: h2mm uninstall [options] \"<mod_name>\""
	echo "Short form: h2mm u"
	echo "Options:"
	echo "	-i <index>		Index of the mod to uninstall."
	echo "Usage:"
	echo "	h2mm uninstall \"Example mod\""
	echo "	h2mm uninstall -i 1 # uninstall mod with index 1"
}

function display_enable_help() {
	echo "Usage: h2mm enable [options] \"<mod_name>\""
	echo "Short form: h2mm e"
	echo "Options:"
	echo "	-i <index>		Index of the mod to enable."
	echo "Usage:"
	echo "	h2mm enable \"Example mod\""
	echo "	h2mm enable -i 1 # enable mod with index 1"
}

function display_disable_help() {
	echo "Usage: h2mm disable [options] \"<mod_name>\""
	echo "Short form: h2mm d"
	echo "Options:"
	echo "	-i <index>		Index of the mod to disable."
	echo "Usage:"
	echo "	h2mm disable \"Example mod\""
	echo "	h2mm disable -i 1 # disable mod with index 1"
}

function display_list_help() {
	echo "Usage: h2mm list"
	echo "Short form: h2mm l"
	echo "List all installed mods."
	echo "Database of mods is stored in Steam/steamapps/common/Helldivers\ 2/data/mods.csv"
	echo "You can rename, delete, or edit this file to manage mods manually."
}

function display_reset_help() {
	echo "Usage: h2mm reset"
	echo "Short form: h2mm r"
	echo "Reset all installed mods."
	echo "Deletes all installed mods and the database file."
	echo "Database of mods is stored in Steam/steamapps/common/Helldivers\ 2/data/mods.csv, along with the mods."
}

function display_export_help() {
	echo "Usage: h2mm export"
	echo "Short form: h2mm ex"
	echo "Export installed mods and database to a zip file (in h2mm format, archive with csv)."
}

function display_import_help() {
	echo "Usage: h2mm import"
	echo "Short form: h2mm im"
	echo "Import mods and database from an archive file (coming from h2mm)."
}

function display_modpack_list_help() {
	echo "Usage: h2mm modpack-list"
	echo "Short form: h2mm ml"
	echo "List all installed modpacks."
	echo "Database of modpacks is stored in Steam/steamapps/common/Helldivers\ 2/data/modpacks/modpacks.csv"
	echo "You can rename, delete, or edit this file to manage modpacks manually."
}

function display_modpack_create_help() {
	echo "Usage: h2mm modpack-create \"<modpack_name>\""
	echo "Short form: h2mm mc"
	echo "Create a modpack from the currently installed mods."
}

function display_modpack_switch_help() {
	echo "Usage: h2mm modpack-switch [options] \"<modpack_name>\""
	echo "Short form: h2mm ms"
	echo "Options:"
	echo "	-i <index>		Index of the modpack to switch to."
	echo "Switch to a modpack by name or index."
}

function display_modpack_reset_help() {
	echo "Usage: h2mm modpack-reset"
	echo "Short form: h2mm mr"
	echo "Reset all installed modpacks."
	echo "Deletes all installed modpacks and the database file."
	echo "Database of modpacks is stored in Steam/steamapps/common/Helldivers\ 2/data/modpacks/modpacks.csv, along with the modpacks."
}

function display_modpack_delete_help() {
	echo "Usage: h2mm modpack-delete [options] \"<modpack_name>\""
	echo "Short form: h2mm md"
	echo "Options:"
	echo "	-i <index>		Index of the modpack to delete."
	echo "Delete a modpack by name or index."
}

function display_modpack_overwrite_help() {
	echo "Usage: h2mm modpack-overwrite [options] \"<modpack_name>\""
	echo "Short form: h2mm mo"
	echo "Options:"
	echo "	-i <index>		Index of the modpack to overwrite."
	echo "Overwrite a modpack (the mods that it uses) by name or index."
}

# --- Main Functions ---

# Check for updates

function check_for_updates() {
	if [[ -f "$LAST_CHECKED_UPDATE_FILE" ]]; then
		last_update=$(cat "$LAST_CHECKED_UPDATE_FILE")
		if [[ "$(date +%s)" -lt "$(date +%s -d "$last_update + 1 hour")" ]]; then
			return
		fi
	else
		echo "$(date +%Y-%m-%dT%H:%M:%S)" > "$LAST_CHECKED_UPDATE_FILE"
		exit 0
	fi

	latest_version=$(curl -sS "$VERSION_URL")
	if [[ $? -ne 0 ]]; then
		echo "${RED}Error:${NC} Could not check for updates." >&2
		return
	fi

	if [[ "$latest_version" != "$VERSION" ]]; then
		echo -e "${ORANGE}Info:${NC} A new version of h2mm is available: ${ORANGE}$VERSION${NC} -> ${GREEN}$latest_version${NC}" >&2
		echo -e "${ORANGE}Info:${NC} Run \"h2mm update\" to update." >&2
	fi

	echo "$(date +%Y-%m-%dT%H:%M:%S)" > "$LAST_CHECKED_UPDATE_FILE"
}

# Upgrade/downgrade logic

function downgrade_mods() {
	local files="$1"
	declare -A downgrades_versions
	declare -A downgrades_to_apply

	for file in $files; do
		# save the basename for the files that were deleted into a hash table, so we can downgrade mods with greater version number
		# also depending on how many patches the mod has, we need to downgrade with more versions
		current_version=$(echo "$file" | grep -oP '(?<=patch_)\d+')
		base_name=$(get_basename "$file")

		downgrades_versions["$base_name"]=$current_version

		# count how many unique patches the mod has
		[[ -z "${downgrades_to_apply["$base_name"]+unset}" ]] && downgrades_to_apply["$base_name"]=$(echo $files | tr ' ' '\n' | grep "$base_name" | sed -E "s/(.*_[0-9]+).*/\1/" | sort -u | wc -l)
	done

	# downgrade any necessary mods - it takes ~20 minutes to re-understand this code so I'm writing a comment here
	# for each base name, find all files that have the same base name, and are greater than the current version, and downgrade them
	# the downgrades_versions hash table stores the current version, so we can compare it with the version of the files
	# the downgrades_to_apply hash table stores the number of patches the mod has, so we can downgrade with more versions
	# for example, if we have:
	# mod 1: AAA.patch_0 AAA.patch_0.stream AAA.patch_1 AAA.patch_1.stream
	# mod 2: AAA.patch_2 AAA.patch_2.stream AAA.patch_3 AAA.patch_3.stream
	# mod 3: AAA.patch_4 AAA.patch_4.stream AAA.patch_5 AAA.patch_5.stream
	# if we remove mod with index 2, we need to downgrade mod with index 3 (which has patch version 4 and 5 > 3 (biggest last patch removed)) by 2 versions,
	# the number 2 we get by counting the number of unique base names (without extensions like .stream, but with the .patch_[0-9]) in the files
	for base_name in "${!downgrades_to_apply[@]}"; do
		# find all files that have the same base name, and are greater than the current version, and downgrade them
		IFS=$'\n' mods_to_downgrade=($(ls "$MODS_DIR/$base_name"* 2>/dev/null | sort -V)); unset IFS

		for mod in "${mods_to_downgrade[@]}"; do
			mod=$(get_filename_without_path "$mod")
			patch_version=$(echo $mod | grep -oP '(?<=patch_)\d+')

			if [[ $patch_version -gt ${downgrades_versions[$base_name]} ]]; then
				new_version=$((patch_version - downgrades_to_apply["$base_name"]))
				extension=$(get_extension "$mod")

				new_patch="${base_name}.patch_${new_version}${extension}"
				mv "$MODS_DIR/$mod" "$MODS_DIR/$new_patch"

				[[ $? -ne 0 ]] && { echo -e "${RED}Error${NC}: Could not downgrade mod file $mod." >&2; exit 1; }
				echo -e "Downgraded ${ORANGE}$mod${NC} to ${GREEN}\$MODS_DIR/$new_patch${NC}." >&2

				# save changes in database as well
				sed -i "s/\(\b$mod\b\)/$new_patch/" "$DB_FILE"
			fi
		done
	done
}

function upgrade_mods() {
	local files="$1"
	declare -A upgrade_versions
	declare -A upgrades_to_apply

	# opposite of downgrade_mods
	for file in $files; do
		# remove disabled_ prefix if it exists
		file=$(remove_disabled_prefix "$file")

		current_version=$(echo "$file" | grep -oP '(?<=patch_)\d+')
		base_name=$(get_basename "$file")

		# basically save the lowest number, by limiting the setting of the key to the first time we see it
		[[ -z "${upgrade_versions["$base_name"]+unset}" ]] && upgrade_versions["$base_name"]=$current_version

		[[ -z "${upgrades_to_apply["$base_name"]+unset}" ]] && upgrades_to_apply["$base_name"]=$(echo $files | tr ' ' '\n' | grep "$base_name" | sed -E "s/(.*_[0-9]+).*/\1/" | sort -u | wc -l)
	done


	for base_name in "${!upgrades_to_apply[@]}"; do
		IFS=$'\n' mods_to_upgrade=($(ls "$MODS_DIR/$base_name"* 2>/dev/null | sort -V)); unset IFS

		for mod in "${mods_to_upgrade[@]}"; do
			mod=$(get_filename_without_path "$mod")
			patch_version=$(echo $mod | grep -oP '(?<=patch_)\d+')

			if [[ $patch_version -ge ${upgrade_versions[$base_name]} ]]; then
				new_version=$((patch_version + upgrades_to_apply["$base_name"]))
				extension=$(get_extension "$mod")

				new_patch="${base_name}.patch_${new_version}${extension}"
				mv "$MODS_DIR/$mod" "$MODS_DIR/$new_patch"

				[[ $? -ne 0 ]] && { echo -e "${RED}Error${NC}: Could not upgrade mod file $mod." >&2; exit 1; }
				echo -e "Upgraded ${ORANGE}$mod${NC} to ${GREEN}\$MODS_DIR/$new_patch${NC}." >&2

				sed -i "s/\(\b$mod\b\)/$new_patch/" "$DB_FILE"
			fi
		done
	done
}

# Mod management

function mod_disable() {
	local mod_name=""
	local mod_index=""

	[[ $# -eq 0 ]] && { display_disable_help; exit 0; }

	# parse arguments
	while [[ $# -gt 0 ]]; do
		case "$1" in
			-i)
				mod_index="$2"; shift 2
				;;
			--help|-h)
				display_disable_help; exit 0
				;;
			*)
				mod_name="$1"; shift 1
				;;
		esac
	done

	if [[ -z "$mod_name" && -z "$mod_index" ]]; then
		echo -e "${RED}Error${NC}: Mod name or index is required to disable." >&2
		exit 1
	fi

	# find mod files
	get_mod_name_and_index

	if [[ "$status" == "DISABLED" ]]; then
		echo -e "${RED}Error${NC}: Mod $mod_name is already disabled." >&2
		exit 1
	fi

	# disable each mod file by adding disabled_ to the start of the filename
	files=$(get_files_by_entry_from_db "$entry")
	for file in $files; do
		[[ ! -f "$MODS_DIR/$file" ]] && { echo -e "${RED}Error${NC}: Mod file $file does not exist." >&2; exit 1; }

		disabled_file="disabled_$file"
		while [[ -f "$MODS_DIR/$disabled_file" ]]; do
			disabled_file="disabled_$disabled_file"
		done

		mv "$MODS_DIR/$file" "$MODS_DIR/$disabled_file"

		[[ $? -ne 0 ]] && { echo -e "${RED}Error${NC}: Could not disable mod file $file." >&2; exit 1; }
		echo -e "Disabled ${ORANGE}$file${NC} (changed to ${GREEN}\$MODS_DIR/$disabled_file${NC})." >&2

		# save change to db
		sed -i "/^$mod_index,/ s/\(\b$file\b\)/$disabled_file/" "$DB_FILE"
	done

	# downgrade mods with greater version number
	downgrade_mods "$files"

	# update the database
	sed -i "/^$mod_index,/s/ENABLED/DISABLED/" "$DB_FILE"

	[[ $? -ne 0 ]] && { echo -e "${RED}Error${NC}: Could not disable mod." >&2; exit 1; }
	echo -e "Mod $mod_name ${ORANGE}disabled${NC} successfully." >&2
}

function mod_enable() {
	local mod_name=""
	local mod_index=""

	[[ $# -eq 0 ]] && { display_enable_help; exit 0; }

	# parse arguments
	while [[ $# -gt 0 ]]; do
		case "$1" in
			-i)
				mod_index="$2"; shift 2
				;;
			--help|-h)
				display_enable_help; exit 0
				;;
			*)
				mod_name="$1"; shift 1
				;;
		esac
	done

	[[ -z "$mod_name" && -z "$mod_index" ]] && { echo -e "${RED}Error${NC}: Mod name or index is required to enable." >&2; exit 1; }

	# find mod files
	get_mod_name_and_index

	[[ "$status" == "ENABLED" ]] && { echo -e "${RED}Error${NC}: Mod $mod_name is already enabled." >&2; exit 1; }

	files=$(get_files_by_entry_from_db "$entry")

	# upgrade mods with lower version number
	upgrade_mods "$files"

	# enable each mod file by removing disabled_ from the start of the filename
	for file in $files; do
		enabled_file=$(remove_disabled_prefix "$file")

		# check if the files exists
		[[ -f "$MODS_DIR/$file" ]] || { echo -e "${RED}Error${NC}: Mod file $file does not exist." >&2; exit 1; }

		mv "$MODS_DIR/$file" "$MODS_DIR/$enabled_file"

		# check if the file was moved successfully
		[[ $? -ne 0 ]] && { echo -e "${RED}Error${NC}: Could not enable mod file $file." >&2; exit 1; }
		echo -e "Enabled ${ORANGE}$file${NC} (changed to ${GREEN}\$MODS_DIR/$enabled_file${NC})." >&2

		# save change to db
		sed -i "/^$mod_index,/ s/\(\b$file\b\)/$enabled_file/" "$DB_FILE"
	done

	# update the database
	sed -i "/^$mod_index,/s/DISABLED/ENABLED/" "$DB_FILE"

	[[ $? -ne 0 ]] && { echo -e "${RED}Error${NC}: Could not enable mod." >&2; exit 1; }
	echo -e "Mod $mod_name ${GREEN}enabled${NC} successfully." >&2
}

function modpack_reset() {
	:
}

function mod_reset() {
	if [[ "$1" == "--help" || "$1" == "-h" ]]; then
		display_reset_help
		exit 0
	fi

	local without_modpacks=false
	[[ "$1" == "--without-modpacks" ]] && without_modpacks=true

	echo -ne "Are you sure you want to ${RED}reset${NC} all installed mods? (Y/n): " >&2
	read -r confirm
	if [[ "$confirm" == "y" || "$confirm" == "Y" || "$confirm" = "" ]]; then
		rm -f "$MODS_DIR"/*.patch_*
		rm -f "$DB_FILE"
		rm -f "$H2PATH"
		echo "Mods and related database file deleted."

		[[ $without_modpacks == false ]] && modpack_reset --force
	else
		echo "Reset cancelled." >&2
		exit 1
	fi
}

function mod_install() {
	local mod_name=""
	local mod_dir=()
	local mod_files=()
	local mod_zip=()

	[[ $# -eq 0 ]] && { display_install_help; exit 0; }

	# parse arguments
	while [[ $# -gt 0 ]]; do
		case "$1" in
		-n)
			mod_name="$2"; shift 2
			;;
		--help|-h)
			display_install_help; exit 0
			;;
		*)
			if [[ -f "$1" && "$1" == *.zip ]]; then
				mod_zip+=("$1")
			elif [[ -d "$1" ]]; then
				mod_dir+=("$1")
			else
				mod_files+=("$1")
			fi
			shift
			;;
		esac
	done

	# edge case when there is a combination of mod zips and directories, call function for all zips and dirs
	if [[ ${mod_zip} && ${mod_dir} ]]; then
		mod_install "${mod_zip[@]}"
		mod_install "${mod_dir[@]}"

		# reset arrays
		mod_zip=()
		mod_dir=()

		# if there are no more arguments, exit
		[[ ${#mod_files[@]} -eq 0 ]] && exit 0
	fi

	# if there's more than 1 zip, call recursively
	while [[ ${#mod_zip[@]} -gt 1 ]]; do
		mod_install "${mod_zip[0]}"
		mod_zip=("${mod_zip[@]:1}")
	done

	# extract the zip file and pass it to mod dirs
	if [[ -n "$mod_zip" ]]; then
		command -v unzip &> /dev/null || { echo -e "${RED}Error${NC}: unzip package is not installed." >&2; exit 1; }

		[[ ! -f "$mod_zip" ]] && { echo -e "${RED}Error${NC}: Zip file $mod_zip does not exist." >&2; exit 1; }

		# if the name is not specified, use the name of the directory, last sed for making nexusmods names not have numbers
		if [[ -z "$mod_name" ]]; then
			mod_name=$(basename "$mod_zip" | sed -E 's/\.zip//' | awk -F/ '{print $NF}' | sed -E 's/-[0-9]+-.*//')
		fi

		# mod_dir as a temporary directory
		mod_dir+=$(mktemp -d)
		unzip -qq "$mod_zip" -d "$mod_dir"
	fi

	# if there's more than 1 directory, call recursively
	while [[ ${#mod_dir[@]} -gt 1 ]]; do
		mod_install "${mod_dir[0]}"
		mod_dir=("${mod_dir[@]:1}")
	done

	# directory containing mod files
	if [[ -n "$mod_dir" ]]; then
		# verify directory exists
		[[ ! -d "$mod_dir" ]] && { echo -e "${RED}Error${NC}: Directory $mod_dir does not exist." >&2; exit 1; }

		# read every file from the directory
		readarray -d '' mod_files < <(find "$mod_dir" -type f -name "*.patch_*" -print0)
		# if the name is not specified, use the name of the directory, last sed for making nexusmods names not have numbers
		if [[ -z "$mod_name" ]]; then
			mod_name=$(echo "$mod_dir" | sed 's:/*$::' | awk -F/ '{print $NF}' | sed -E 's/-[0-9]+-.*//')
		fi
	fi

	# verify minimum information required
	[[ -z "$mod_name" || ${#mod_files[@]} -eq 0 ]] && { echo -e "${RED}Error${NC}: Mod name and files are required." >&2; exit 1; }

	# verify duplicate mod names
	get_mod_name_and_index --do-not-exit
	[[ $mod_index -ne -1 ]] && { echo -e "${RED}Error${NC}: The mod '$mod_name' is already installed."; exit 1; }

	# verify mod files exist
	for file in "${mod_files[@]}"; do
		[[ ! -f "$file" ]] && { echo -e "${RED}Error${NC}: Mod file $file does not exist." >&2; exit 1; }
	done

	# check for mod variants and handle
	# if the mod directory contains more than 1 directory, it means there are multiple variants for the mod
	# prompt the user to choose which variant to install, or install multiple
	readarray -d '' all_dirs < <(find "$mod_dir" -mindepth 1 -type d -print0)

	# filter so that we only have dirs that have *.patch_* files inside them
	filtered_dirs=()
	for dir in "${all_dirs[@]}"; do
		if find "$dir" -maxdepth 1 -type f -name "*.patch_*" -print -quit | grep -q .; then
			filtered_dirs+=("$dir")
		fi
	done

	if [[ ${#filtered_dirs[@]} -gt 1 ]]; then
		echo -e "Multiple mod variants found for mod ${mod_name}." >&2
		for i in "${!filtered_dirs[@]}"; do
			echo "$((i + 1)). $(basename "${filtered_dirs[$i]}")" >&2
		done

		# prompt user to choose
		echo -ne "Enter the number of the variant(s) to install (separated by space) or press Enter to install all: " >&2
		read -a variant_indices
		if [[ -n "${variant_indices[0]}" ]]; then
			# clear mod_files
			mod_files=()

			# get the files from the chosen variant
			for index in "${variant_indices[@]}"; do
				[[ ! "$index" =~ ^[0-9]+$ ]] && { echo -e "${RED}Error${NC}: Invalid variant index." >&2; exit 1; }
				[[ $index -lt 1 || $index -gt ${#filtered_dirs[@]} ]] && { echo -e "${RED}Error${NC}: Variant index out of range." >&2; exit 1; }

				readarray -d '' variant_files < <(find "${filtered_dirs[$((index - 1))]}" -type f -name "*.patch_*" -print0)

				# update mod_name to contain the variant name
				mod_name="${mod_name} [$(basename "${filtered_dirs[$((index - 1))]}")]"

				# add the files to the mod_files array
				mod_files+=("${variant_files[@]}")
			done
		fi
	fi

	# hash table - in case multiple named files are needed for 1 mod install, store the patch count
	declare -A patch_count
	# store the target files so we can put them in the database later
	target_files=()
	# sort the mod files because with the below logic, the .stream and .gpu_resources files need to come after their respective patch files
	IFS=$'\n' mod_files=($(printf "%s\n" "${mod_files[@]}" | sort -t. -k1,1 -k2,2n)); unset IFS

	for file in "${mod_files[@]}"; do
		base_name=$(get_basename "$file")
		patch_prefix="$MODS_DIR/${base_name}.patch_"
		# count already installed patches
		count=$(ls "${patch_prefix}"* 2>/dev/null | grep -E '([0-9]+$)' 2>/dev/null | wc -l)

		# set patch count for file name if it doesn't exist yet
		if [[ -z "${patch_count[$file]+unset}" ]]; then
			patch_count["$file"]=$count
		fi
		# if the file has an extension (e.g. .stream, .gpu_resources), set the last patch number for the next step
		patch_count["$base_name"]=$count

		# if the file has an extension, look for the last patch number and use that, otherwise, the count will be wrong
		extension=$(get_extension "$file")
		if [[ -n "$extension" ]]; then
			target_file="${base_name}.patch_$((patch_count[$base_name] - 1))${extension}"
		else
			target_file="${base_name}.patch_${patch_count[$file]}"
		fi

		target_files+=($target_file)
		cp "$file" "$MODS_DIR/$target_file"

		# verify installation worked
		[[ $? -ne 0 ]] && { echo -e "${RED}Error${NC}: Could not install mod file $file." >&2; exit 1; }
		echo -e "Mod file ${ORANGE}$file${NC} installed at ${GREEN}\$MODS_DIR/$target_file${NC}." >&2
	done

	# add entry to database
	next_id=$(awk -F, 'NR > 1 {last_id = $1} END {print last_id + 1}' "$DB_FILE")
	echo "$next_id,ENABLED,$mod_name,${target_files[*]}" >> "$DB_FILE"
	echo -e "Mod $mod_name ($base_name) ${GREEN}installed${NC} successfully." >&2

	# disable any modpack
	disable_all_modpacks
}

function mod_uninstall() {
	local mod_name=""
	local mod_index=""

	[[ $# -eq 0 ]] && { display_uninstall_help; exit 0; }

	# parse arguments
	while [[ $# -gt 0 ]]; do
		case "$1" in
			-i)
				mod_index="$2"; shift 2
				;;
			--help|-h)
				display_uninstall_help; exit 0
				;;
			*)
				mod_name="$1"; shift 1
				;;
		esac
	done

	[[ -z "$mod_name" && -z "$mod_index" ]] && { echo -e "${RED}Error${NC}: Mod name or index is required to uninstall." >&2; exit 1; }

	# find mod files
	get_mod_name_and_index

	# delete mod files
	files=$(get_files_by_entry_from_db "$entry")

	for file in $files; do
		[[ ! -f "$MODS_DIR/$file" ]] && { echo -e "${RED}Error${NC}: Mod file $file does not exist." >&2; exit 1; }

		echo -e "Removing ${ORANGE}\$MODS_DIR/$file${NC}." >&2
		rm "$MODS_DIR/$file"

		[[ $? -ne 0 ]] && { echo -e "${RED}Error${NC}: Could not remove mod file $file." >&2; exit 1; }
	done

	# downgrade mods with greater version number, only if the mod is enabled
	[[ "$status" == "ENABLED" ]] && downgrade_mods "$files"

	# remove entry from database
	sed -i "/^$mod_index,/d" "$DB_FILE"
	echo -e "Mod $mod_name ${ORANGE}uninstalled${NC} successfully." >&2

	# disable any modpack
	disable_all_modpacks
}

function mod_list() {
	[[ "$1" == "--help" || "$1" == "-h" ]] && { display_list_help; exit 0; }

	[[ $(wc -l < "$DB_FILE") -le 1 ]] && { echo "No mods installed."; return; }

	echo "Installed mods:" >&2

	awk -v GREEN="$GREEN" -v RED="$RED" -v NC="$NC" -F, 'NR > 1 {
	color = ($2 == "DISABLED") ? RED : GREEN;
	if (length($4) > 150) $4 = substr($4, 1, 147) "...";
	printf "%2s. [%s%s%s] %s (%s)\n", $1, color, $2, NC, $3, $4}' "$DB_FILE"
}

function mod_export() {
	[[ "$1" == "--help" || "$1" == "-h" ]] && { display_export_help; exit 0; }

	local save_dir=$(pwd)
	local archive_name="Helldivers_2_Mods_$(date +%Y-%m-%d_%H-%M-%S)"
	local modpack_export=false
	local force=false

	if [[ "$1" == "--modpack" ]]; then
		modpack_export=true
		save_dir="$2"
		archive_name="$3"
	fi

	[[ $(wc -l < "$DB_FILE") -le 1 ]] && { echo "No modpacks saved."; exit 1; }

	if [[ $modpack_export == false ]]; then
		echo -ne "Archive file will be saved to ${save_dir}/${archive_name}. Make? (Y/n): " >&2
		read -r confirm
	fi
	if [[ silent == true || "$confirm" == "y" || "$confirm" == "Y" || "$confirm" = "" ]]; then
		# create a temporary directory to store the mods
		OUT_DIR=$(mktemp -d)
		MODS_EXPORT_DIR="$OUT_DIR/Helldivers 2 Mods"
		mkdir -p "$MODS_EXPORT_DIR"
		cp "$DB_FILE" "$MODS_EXPORT_DIR"

		[[ $? -ne 0 ]] && { echo -e "${RED}Error${NC}: Could not copy mods to target directory." >&2; exit 1; }

		# copy all mod files to the export directory
		for file in $(ls "$MODS_DIR/" 2>/dev/null | grep -E 'patch_.*'); do
			cp "$MODS_DIR/$file" "$MODS_EXPORT_DIR"
		done

		[[ $? -ne 0 ]] && { echo -e "${RED}Error${NC}: Could not export mods. Possibly because no mods are present." >&2; exit 1; }

		# zip up the mods with the current date and time in the name
		[[ -f "$save_dir/${archive_name}.tar.gz" ]] && { echo -e "${RED}Error${NC}: File $save_dir/${archive_name}.tar.gz already exists." >&2; exit 1; }
		tar -czf "$save_dir/${archive_name}.tar.gz" -C "$OUT_DIR" "Helldivers 2 Mods"

		[[ $? -ne 0 ]] && { echo -e "${RED}Error${NC}: Failed to export mods." >&2; exit 1; }
		[[ "$modpack_export" == false ]] && echo -e "Mods ${GREEN}exported${NC} to $save_dir/${archive_name}.tar.gz." >&2
	fi
}

function mod_import() {
	[[ "$1" == "--help" || "$1" == "-h" ]] && { display_import_help; exit 0; }

	local modpack_export=false
	[[ "$1" == "--modpack" ]] && { modpack_export=true; shift 1; }

	[[ ! -f "$1" ]] && { echo -e "${RED}Error${NC}: File $1 does not exist." >&2; exit 1; }

	# reset mods before importing
	[[ modpack_export == false ]] && echo -e "Importing mods will ${RED}reset${NC} your mods." >&2
	mod_reset --without-modpacks

	# extract in temp directory
	OUT_DIR=$(mktemp -d)
	tar -xzf "$1" -C "$OUT_DIR"

	[[ $? -ne 0 ]] && { echo -e "${RED}Error${NC}: Could not import mods. Possibly because the archive is invalid." >&2; exit 1; }

	MODS_EXPORT_DIR="$OUT_DIR/Helldivers 2 Mods"
	[[ ! -d "$MODS_EXPORT_DIR" ]] && { echo -e "${RED}Error${NC}: Could not import mods. Possibly because the archive is invalid." >&2; exit 1; }

	# copy mods
	cp "$MODS_EXPORT_DIR"/* "$MODS_DIR"

	[[ $? -ne 0 ]] && { echo -e "${RED}Error${NC}: Failed to import mods." >&2; exit 1; }

	echo -e "Mods imported ${GREEN}successfully${NC}." >&2
}

# --- Modpacks management ---

function modpack_list() {
	[[ "$1" == "--help" || "$1" == "-h" ]] && { display_modpack_list_help; exit 0; }

	[[ $(wc -l < "$MODPACKS_DB_FILE") -le 1 ]] && { echo "No modpacks saved."; return; }

	echo "Saved modpacks:" >&2

	awk -v GREEN="$GREEN" -v RED="$RED" -v NC="$NC" -F, 'NR > 1{
	color = ($2 == "DISABLED") ? RED : GREEN;
	printf "%2s. [%s%s%s] %s\n", $1, color, $2, NC, $3}' "$MODPACKS_DB_FILE"
}

function modpack_create() {
	local modpack_name=""

	[[ $# -eq 0 ]] && { display_modpack_create_help; exit 0; }

	# if no mods are installed, exit
	[[ $(wc -l < "$DB_FILE") -le 1 ]] && { echo -e "${RED}Error${NC}: No mods installed." >&2; exit 1; }

	# use built-in export function
	modpack_name="$1"
	mod_export --modpack "$MODPACKS_FOLDER" "$modpack_name"

	echo -e "Modpack ${GREEN}created${NC}: \$MODPACKS_FOLDER/$modpack_name.tar.gz" >&2

	# add entry to database
	next_id=$(awk -F, 'NR > 1 {last_id = $1} END {print last_id + 1}' "$MODPACKS_DB_FILE")
	sed -i "s/ENABLED/DISABLED/" "$MODPACKS_DB_FILE"
	echo "$next_id,ENABLED,$modpack_name" >> "$MODPACKS_DB_FILE"
}

function modpack_switch() {
	local modpack_name=""
	local modpack_index=""

	[[ $# -eq 0 ]] && { display_modpack_switch_help; exit 0; }

	# parse arguments
	while [[ $# -gt 0 ]]; do
		case "$1" in
			-i)
				modpack_index="$2"; shift 2
				;;
			--help|-h)
				display_modpack_switch_help; exit 0
				;;
			*)
				modpack_name="$1"; shift 1
				;;
		esac
	done

	[[ -z "$modpack_name" && -z "$modpack_index" ]] && { echo -e "${RED}Error${NC}: Modpack name or index is required to switch." >&2; exit 1; }

	# find modpack files
	get_modpack_name_and_index "$modpack_name" "$modpack_index"

	echo -e "Switching modpacks mods will ${RED}reset${NC} your mods." >&2
	mod_import --modpack "$MODPACKS_FOLDER/$modpack_name.tar.gz"

	echo -e "Modpack ${GREEN}switched${NC}: \$MODPACKS_FOLDER/$modpack_name.tar.gz" >&2

	# save status to db
	sed -i "s/ENABLED/DISABLED/" "$MODPACKS_DB_FILE"
	sed -i "/^$modpack_index,/s/DISABLED/ENABLED/" "$MODPACKS_DB_FILE"
}

function modpack_reset() {
	if [[ "$1" == "--help" || "$1" == "-h" ]]; then
		display_modpack_reset_help
		exit 0
	fi

	local force=false

	[[ "$1" == "--force" ]] && force=true

    if [[ force == false ]]; then
		echo -ne "Are you sure you want to ${RED}reset${NC} all installed modpacks? (Y/n): " >&2
		read confirm
	fi
	if [[ force == true || "$confirm" == "y" || "$confirm" == "Y" || "$confirm" = "" ]]; then
		rm -f "$MODPACKS_FOLDER"/*.tar.gz
		rm -f "$MODPACKS_DB_FILE"
		rmdir "$MODPACKS_FOLDER"
		echo "Modpacks and related database file deleted."
	else
		echo "Reset cancelled." >&2
		exit 1
	fi
}

function modpack_delete() {
	local modpack_name=""
	local modpack_index=""

	[[ $# -eq 0 ]] && { display_modpack_delete_help; exit 0; }

	# parse arguments
	while [[ $# -gt 0 ]]; do
		case "$1" in
			-i)
				modpack_index="$2"; shift 2
				;;
			--help|-h)
				display_modpack_delete_help; exit 0
				;;
			*)
				modpack_name="$1"; shift 1
				;;
		esac
	done

	[[ -z "$modpack_name" && -z "$modpack_index" ]] && { echo -e "${RED}Error${NC}: Modpack name or index is required to delete." >&2; exit 1; }

	get_modpack_name_and_index "$modpack_name" "$modpack_index"

	rm -f "$MODPACKS_FOLDER/$modpack_name.tar.gz"

	[[ $? -ne 0 ]] && { echo -e "${RED}Error${NC}: Could not delete modpack." >&2; exit 1; }
	echo -e "Modpack ${GREEN}deleted${NC}: \$MODPACKS_FOLDER/$modpack_name.tar.gz" >&2

	# remove entry from database
	sed -i "/^$modpack_index,/d" "$MODPACKS_DB_FILE"
}

function modpack_overwrite() {
	[[ $# -eq 0 ]] && { display_modpack_overwrite_help; exit 0; }

	local modpack_name=""
	local modpack_index=""

	# parse arguments
	while [[ $# -gt 0 ]]; do
		case "$1" in
			-i)
				modpack_index="$2"; shift 2
				;;
			--help|-h)
				display_modpack_save_help; exit 0
				;;
			*)
				modpack_name="$1"; shift 1
				;;
		esac
	done

	[[ -z "$modpack_name" && -z "$modpack_index" ]] && { echo -e "${RED}Error${NC}: Modpack name or index is required to save." >&2; exit 1; }

	get_modpack_name_and_index "$modpack_name" "$modpack_index"

	# if the modpack doesn't exist, exit
	[[ ! -f "$MODPACKS_FOLDER/$modpack_name.tar.gz" ]] && { echo -e "${RED}Error${NC}: Modpack $modpack_name does not exist." >&2; exit 1; }


	rm -f "$MODPACKS_FOLDER/$modpack_name.tar.gz"

	[[ $? -ne 0 ]] && { echo -e "${RED}Error${NC}: Could not delete modpack." >&2; exit 1; }

	# use built-in export function
	mod_export --modpack "$MODPACKS_FOLDER" "$modpack_name"

	echo -e "Modpack ${GREEN}saved${NC}: \$MODPACKS_FOLDER/$modpack_name.tar.gz" >&2
	sed -i "/^$modpack_index,/s/DISABLED/ENABLED/" "$MODPACKS_DB_FILE"
}

function self_update() {
	latest_version=$(curl -sS "$VERSION_URL")

	if [[ "$latest_version" == "$VERSION" ]]; then
		echo -e "h2mm is already up-to-date." >&2
		exit 0
	fi

	echo -e "Starting update script..." >&2

	# Run the installer for the latest version
	bash -c "$(curl -fsSL https://raw.githubusercontent.com/v4n00/h2mm-cli/refs/heads/master/install.sh)"
	exit 0
}

# --- Main ---

function main() {
	[[ $# -lt 1 ]] && { display_help; exit 1; }

	command="$1"
	shift
	initialize_directories
	initialize_modpack_directories
	check_for_updates

	case "$command" in
		"install"|"i")
			mod_install "$@"
			;;
		"list"|"l")
			mod_list "$@"
			;;
		"uninstall"|"u")
			mod_uninstall "$@"
			;;
		"enable"|"e")
			mod_enable "$@"
			;;
		"disable"|"d")
			mod_disable "$@"
			;;
		"export"|"ex")
			mod_export "$@"
			;;
		"import"|"im")
			mod_import "$@"
			;;
		"modpack-list"|"ml")
			modpack_list "$@"
			;;
		"modpack-create"|"mc")
			modpack_create "$@"
			;;
		"modpack-delete"|"md")
			modpack_delete "$@"
			;;
		"modpack-overwrite"|"mo")
			modpack_overwrite "$@"
			;;
		"modpack-switch"|"ms")
			modpack_switch "$@"
			;;
		"modpack-reset"|"mr")
			modpack_reset "$@"
			;;
		"reset"|"r")
			mod_reset "$@"
			;;
		"version"|"v"|"-v"|"--version")
			echo "${VERSION}"
			;;
		"update"|"up")
			self_update
			;;
		"help"|"--help"|"-h"|"h")
			display_help
			;;
		*)
			display_help
			;;
	esac
}

main "$@"