#!/bin/bash


# Copyright 2024 Daniel Almeida Martins
# License GPL-3.0-or-later
#
# This program is free software: you can redistribute it and/or modify it under
# the terms of the GNU General Public License as published by the Free Software
# Foundation, either version 3 of the License, or (at your option) any later
# version.
#
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along with
# this program. If not, see <https://www.gnu.org/licenses/>.


# NOTE
# This script performs two main operations, backup and restore.
# - On backup, it archives and compresses the savegame files. These archives are
#   stored in a directory defined below.
# - On restore, it restores the savegame files based on a backup archive. For
#   added cautiousness, right before the restore operation, a backup of the
#   current savegame files is performed to a temporary directory. Check the
#   restore_savegame function for these implementation details.
# Backup archives are identified by their TAG, which is simply the date and time
# when they were created (using the ISO 8601 format YYYYMMDDThhmm).

# NOTE
# The following variables control the core behaviour of the script:
# backup_folder         : The folder where the backup archives are stored.
# backup_extension      : File extension that determines the compression used.

declare version=2.1
declare backup_folder="${HOME}/Documents/savegame"
declare backup_extension="tzst"

# NOTE
# Below is the list of supported games. Each game needs three entries:
# game_GAME             : The display name of the game.
# include_GAME          : The directory to be backed up.
# exclude_GAME          : A list of files to be excluded from the backup.
# Each game must use a different GAME which should be an acronym since it will
# also be used from the command line when you want to reference a specific game.

declare game_ash="A Short Hike"
declare include_ash="${HOME}/.config/unity3d/adamgryu/A Short Hike"
declare exclude_ash=()

declare game_aermoo="AER Memories of Old"
declare include_aermoo="${HOME}/.local/share/Daedalic Entertainment GmbH/Aer"
declare exclude_aermoo=("./CLog.log" "config.ini")

declare game_aor="Art of Rally"
declare include_aor="${HOME}/.config/unity3d/Funselektor Labs/art of rally/Save"
declare exclude_aor=()

declare game_darwin="Darwinia"
declare include_darwin="${HOME}/.darwinia/full/users"
declare exclude_darwin=()

declare game_emud="Dolphin Emulator"
declare include_emud="${HOME}/.local/share/dolphin-emu/GC"
declare exclude_emud=()

declare game_epistory="Epistory"
declare include_epistory="${HOME}/.config/unity3d/Fishing Cactus/Epistory"
declare exclude_epistory=()

declare game_exap="EXAPUNKS"
declare include_exap="${HOME}/.local/share/EXAPUNKS"
declare exclude_exap=("*/config.cfg" "*/log.dat")

declare game_lcbbs="Last Call BBS"
declare include_lcbbs="${HOME}/.local/share/Last Call BBS"
declare exclude_lcbbs=("*/config.cfg" "*/log.dat")

declare game_oxen="OXENFREE"
declare include_oxen="${HOME}/.config/unity3d/Night School Studio/Oxenfree/save"
declare exclude_oxen=()

declare game_pa="Prison Architect"
declare include_pa="${HOME}/.Prison Architect/saves"
declare exclude_pa=()

declare game_quake="Quake"
declare include_quake="${HOME}/.quakespasm"
declare exclude_quake=()

declare game_q3a="Quake 3 Arena"
declare include_q3a="${HOME}/.q3a"
declare exclude_q3a=("*/*.pk3")

declare game_rtmi="Return to Monkey Island"
declare include_rtmi="${HOME}/.local/share/Terrible Toybox/Return to Monkey Island"
declare exclude_rtmi=()

declare game_sh="Super Hexagon"
declare include_sh="${HOME}/.local/share/SuperHexagon"
declare exclude_sh=()

declare game_wfto="War for the Overworld"
declare include_wfto="${HOME}/Games/War for the Overworld/game/WFTOGame_Data/GameData"
declare exclude_wfto=("./Options.txt")

declare game_yuzu="YUZU"
declare include_yuzu="${HOME}/Games/yuzu/files/data/.local/yuzu/nand"
declare exclude_yuzu=("*/Contents")


print_game_info() {
    declare game=$1
    declare game_def="game_${game}"
    declare -n include="include_${game}"
    declare installed_status=$([ -d "${include}" ] && echo "[installed]" || echo "")
    printf "%-24s\t%-8s\t%s\n" "${!game_def}" "${game}" "${installed_status}"
    return
}

list_savegames() {
    declare game=$1
    declare savegames=(`ls "${backup_folder}" | grep "^${game}_" | sort`)
    declare it
    for it in ${savegames[@]}; do
        declare basename=$(basename ${it})
        declare filename=${basename%%.*}
        declare parts=(${filename//_/ })
        declare game=${parts[0]}
        declare date=${parts[1]}
        declare date_iso="${date:(0):4}-${date:(4):2}-${date:(6):2} ${date:(9):2}:${date:(11):2}:${date:(13):2}"
        printf "%-24s\t%-8s\t%s\n" "${date_iso}" "${game}" "${date}"
    done
    return
}

backup_savegame() {
    declare game=$1
    declare tag=$2
    declare -n include="include_${game}"
    declare -n exclude="exclude_${game}"

    # Check if game is installed.
    if ! [ -d "${include}" ]; then
        printf "${script}: backup not performed because '$game' is not installed.\n"
        exit 1
    fi

    printf "Backing up '${game}' '${tag}'..."
    tar --auto-compress --create --file "${backup_folder}/${game}_${tag}.${backup_extension}" "${exclude[@]/#/--exclude=}" --directory "${include}" .
    printf " done.\n"
    return
}

restore_savegame() {
    declare game=$1
    declare tag=$2
    declare -n include="include_${game}"
    declare -n exclude="exclude_${game}"
    declare date=`date +"%Y%m%dT%H%M%S"`

    # Check if game is installed.
    if ! [ -d "${include}" ]; then
        printf "${script}: restore not performed because '$game' is not installed.\n"
        exit 1
    fi

    printf "Restoring '${game}' '${tag}'..."

    # Backup savegame directory before restoring.
    declare savegame_backup=$(mktemp --tmpdir=/tmp "savegame.backup.${game}_${date}.XXXXXXXX.${backup_extension}")
    tar --auto-compress --create --file "${savegame_backup}" "${exclude[@]/#/--exclude=}" --directory "${include}" .

    # Extract selected savegame.
    tar --auto-compress --extract --file "${backup_folder}/${game}_${tag}.${backup_extension}" --directory "${include}"
    printf " done.\n"
    return
}


declare script=$(basename $0)
declare action=$1
declare -a supported_games=(`compgen -v game_`)
supported_games=("${supported_games[@]#game_}")
mkdir -p "$backup_folder"
case "${action}" in

    # List available games or backups of game defined in argument.
    "--list" | "-l")
    declare game=$2
    if [ -z "$game" ]; then
        for it in ${supported_games[@]}; do
            print_game_info $it
        done
    elif ! [ -v "game_${game}" ]; then  # Check if game is undefined.
        echo "${script}: game '${game}' not found."
        exit 22
    else
        list_savegames $game
    fi
    ;;


    # List backups for all games.
    "--list-all" | "-L")
#     declare -a supported_games=(`compgen -v game_`)
    declare last_item="${supported_games[-1]#game_}"

    for it in ${supported_games[@]}; do
        declare game="${it#game_}"
        print_game_info $it
        list_savegames $game
        if [ "$game" != "$last_item" ]; then
            printf "\n"
        fi
    done
    ;;


    # Backup save game.
    "--backup" | "-b")
    declare game=$2
    if ! [ -v "game_${game}" ]; then    # Check if game is undefined.
        echo "${script}: game '${game}' not found."
        exit 22
    fi
    declare tag=`date +"%Y%m%dT%H%M%S"`
    backup_savegame $game $tag
    ;;


    # Restore save game.
    "--restore" | "-r")
    declare game=$2
    declare tag=$3
    if ! [ -v "game_${game}" ]; then    # Check if game is undefined.
        echo "${script}: game '${game}' not found."
        exit 22
    fi
    if [ -z "$tag" ]; then              # Check if tag is undefined.
        # Search for the latest backup.
        declare savegames=(`ls "${backup_folder}" | grep "^${game}_" | sort`)
        if [ ${#savegames[@]} -eq 0 ]; then
            echo "${script}: no backups found."
            exit 61
        fi
        declare selected="${savegames[-1]}"
        tag="${selected#${game}_}"              # Substring removal: game name from front.
        tag="${tag%%.*}"                        # Substring removal: file extension from back.
    fi
    restore_savegame $game $tag
    ;;


    # Show help.
    "--help" | "-h")
    printf -- "Usage: ${script} OPTION [GAME] [TAG]\n"
    declare options=(
        "-l, --list [GAME]          " "List supported games. Provide GAME to list backup TAGs."
        "-L, --list-all             " "List all backup TAGs."
        "-b, --backup GAME          " "Backup GAME savegame data. Displays new backup TAG."
        "-r, --restore GAME [TAG]   " "Restore GAME savegame data. Omit TAG to use last backup."
        "-h, --help                 " "Display this help and exit."
        "-v, --version              " "Output version information and exit."
    )
    for ((idx=0; idx<${#options[@]}; idx+=2)); do
        printf -- "  %s\t%s\n" "${options[$idx]}" "${options[$idx+1]}"
    done
    printf "\nNotes\n"
    printf -- "- Backup folder '%s'.\n" ${backup_folder}
    printf -- "- Backup extension '%s.'\n" ${backup_extension}
    ;;


    # Show version.
    "--version" | "-v")
    echo "SaveGame Saver version ${version}"
    echo "Copyright 2024 Daniel Martins"
    echo "License GPL-3.0-or-later"
    ;;


    # Unknown option.
    *)
    echo "${script}: invalid option '${action}'."
    echo "Try '${script} --help' for more information."
    exit 22
    ;;

esac

exit 0