#!/bin/bash
EM_CONFIG_PATH="$HOME/.config/EnlivenMinetest"
EM_CACHE_PATH="$HOME/.cache/EnlivenMinetest"
GIT_REPOS_PATH="$EM_CACHE_PATH/git"
GIT_BRANCHES_PATH="$EM_CACHE_PATH/git-branches"
MT_ENV_RUP_NAME="minetestenv-in-place.rc"
if [ -z "$EM_TMP" ]; then
    EM_TMP=/tmp/EnlivenMinetest
fi
#QUIET=true
scripting_rc_path=~/.config/EnlivenMinetest/scripting.rc
if [ -f "$EM_CONFIG_PATH/scripting.rc" ]; then
    echo "* [$MT_ENV_RUP_NAME] using $scripting_rc_path..."
    source $scripting_rc_path
    # may contain any variables above, plus:
    # * enable_run_after_compile: if true, then run the server, such as
    #   ~/mts-CenterOfTheSun.sh
else
    echo "* \"$scripting_rc_path\" is not present and has been skipped."
    echo "  The file can contain settings such as:"
    echo "    enable_run_after_compile=true"
    echo "    REPO_PATH=$HOME/Downloads/git/EnlivenMinetest"
fi

if [ -z "$REPO_PATH" ]; then
    TRY_REPO_PATH="$HOME/git/EnlivenMinetest"
    #if [ -d "$TRY_REPO_PATH" ]; then
    REPO_PATH="$TRY_REPO_PATH"
    #fi
    TRY_REPO_PATH="$HOME/Downloads/git/EnlivenMinetest"
    if [ -d "$TRY_REPO_PATH" ]; then
        REPO_PATH="$TRY_REPO_PATH"
    fi
    TRY_REPO_PATH="`pwd`"
    if [ -f "$TRY_REPO_PATH/$MT_ENV_RUP_NAME" ]; then
        REPO_PATH="$TRY_REPO_PATH"
    fi
    if [ -d "$REPO_PATH" ]; then
        echo "* [minetestenv-in-place.rc] using REPO_PATH \"$REPO_PATH\""
    fi
fi
#if [ ! -d "$REPO_PATH" ]; then
    # "[$MT_ENV_RUP_NAME] WARNING: REPO_PATH \"$REPO_PATH\" does not exist, so certain features will not be available."
#fi
customExit() {
    errorCode=1
    if [ ! -z "$2" ]; then
        errorCode="$2"
    fi
    cat <<END

ERROR:
$1


Waiting 3s before exit...
END
    sleep 3
    exit $errorCode
}

customWarn() {
    cat <<END

WARNING:
$1


END
    echo -en "\a" > /dev/tty0  # beep (You must specify a tty path if not in console mode)
    #echo "Press Ctrl+C to cancel..."
    sleep 1
    #echo -en "\a" > /dev/tty0
    echo "3..."
    sleep 1
    #echo -en "\a" > /dev/tty0
    echo "2..."
    sleep 1
    #echo -en "\a" > /dev/tty0
    echo "1..."
    sleep 1
}

install_shortcut(){
    enable_clear_icon_cache=false

    _SRC_SHORTCUT_PATH=$1
    if [ ! -f "$_SRC_SHORTCUT_PATH" ]; then
        customExit "The shortcut \"$_SRC_SHORTCUT_PATH\" is missing."
    fi
    _DST_SHORTCUT_NAME=$2
    # _CAPTION is optional (original "Name" is kept if not specified)
    _EXEC=$3
    _WORKING_DIR=$4
    _ICON=$5
    _CAPTION=$6
    dest_icons=$HOME/.local/share/applications
    dest_icon=$dest_icons/$_DST_SHORTCUT_NAME
    if [ ! -d "$dest_icons" ]; then
        mdkir -p "$dest_icons" || customExit "mkdir -p \"$dest_icons\" failed."
    fi
    # if [ -f "$dest_icon" ]; then
        # comment since never fixes broken icon anyway
        # TODO: fixed bad cache even if icon was rewritten properly after written improperly
        # * not tried yet:
        #   * rm $HOME/.kde/share/config/kdeglobals
        # enable_clear_icon_cache=true
    # fi
    echo "* writing icon '$dest_icon'..."
    if [ ! -z "$_ICON" ]; then
        if [ ! -z "$_CAPTION" ]; then
            cat "$_SRC_SHORTCUT_PATH" | grep -v "^Icon=" | grep -v "^Path=" | grep -v "^Exec=" | grep -v "^Name=" > "$dest_icon"
        else
            cat "$_SRC_SHORTCUT_PATH" | grep -v "^Icon=" | grep -v "^Path=" | grep -v "^Exec=" > "$dest_icon"
        fi
    else
        if [ ! -z "$_CAPTION" ]; then
            cat "$_SRC_SHORTCUT_PATH" | grep -v "^Path=" | grep -v "^Exec=" | grep -v "^Name=" > "$dest_icon"
        else
            cat "$_SRC_SHORTCUT_PATH" | grep -v "^Path=" | grep -v "^Exec=" > "$dest_icon"
        fi
    fi
    # Icon must be an absolute path (other variables use $HOME in
    # desktop file above), so exclude it above and rewrite it below:
    echo "Path=$_WORKING_DIR" >> "$dest_icon"
    if [ ! -z "$_CAPTION" ]; then
        echo "Name=$_CAPTION" >> "$dest_icon"
    fi
    if [ ! -z "$_ICON" ]; then
        echo "Icon=$_ICON" >> "$dest_icon"
    fi
    echo "Exec=$_EXEC" >> "$dest_icon"
    if [ -d "$HOME/Desktop" ]; then
        cp -f "$dest_icon" "$HOME/Desktop/$_DST_SHORTCUT_NAME"
    fi
    chmod +x "$HOME/Desktop/$_DST_SHORTCUT_NAME"
    if [ "@$enable_clear_icon_cache" = "@true" ]; then
        if [ -f "`command -v gnome-shell`" ]; then
            echo "Refreshing Gnome icons..."
            gnome-shell --replace & disown
            sleep 10
        fi
        if [ -f "$HOME/.cache/icon-cache.kcache" ]; then
            echo "clearing $HOME/.cache/icon-cache.kcache..."
            rm $HOME/.cache/icon-cache.kcache
        fi
        if [ -f "`command -v kquitapp5`" ]; then
            echo "Refreshing KDE icons..."
            if [ -f "`command -v kstart5`" ]; then
                kquitapp5 plasmashell && kstart5 plasmashell
            else
                kquitapp5 plasmashell && kstart plasmashell
            fi
            sleep 15
        fi
        if [ -f "`command -v xfce4-panel`" ]; then
            echo "Refreshing Xfce icons..."
            xfce4-panel -r && xfwm4 --replace
            sleep 5
        fi
        if [ -f "`command -v lxpanelctl`" ]; then
            echo "Refreshing LXDE icons..."
            lxpanelctl restart && openbox --restart
            sleep 5
        fi
    fi
}

install_mt_in_place_shortcut(){
    # You must either set SHORTCUT_PATH or the first parameter to a
    # valid Minetest ".desktop" file.
    # You must either set INSTALL_PATH or the second parameter to a
    # valid installed minetest directory (containing bin).
    #if [ ! -f "$SHORTCUT_PATH" ]; then
        if [ ! -z "$1" ]; then
            SHORTCUT_PATH="$1"
        fi
    #fi
    #if [ ! -d "$INSTALL_PATH" ]; then
        if [ ! -z "$2" ]; then
            INSTALL_PATH="$2"
        fi
    #fi
    if [ ! -f "$SHORTCUT_PATH" ]; then
        echo "* WARNING: The SHORTCUT_PATH $SHORTCUT_PATH does not exist."
    elif [ ! -d "$INSTALL_PATH" ]; then
        echo "* ERROR: The INSTALL_PATH $INSTALL_PATH does not exist."
    else
        EXEC_PATH="$INSTALL_PATH/bin/minetest"
        if [ ! -f "$EXEC_PATH" ]; then
            echo "* WARNING: The Minetest executable is not present: \"$EXEC_PATH\""
        fi
        WORKING_DIR_PATH="$INSTALL_PATH/bin"
        if [ ! -d "$WORKING_DIR_PATH" ]; then
            echo "* WARNING: The Minetest working directory is not present: \"$WORKING_DIR_PATH\""
        fi
        MT_ICON="$INSTALL_PATH/misc/minetest-xorg-icon-128.png"
        if [ ! -f "$MT_ICON" ]; then
            echo "* WARNING: The Minetest icon is not present: \"$MT_ICON\""
        fi
        install_shortcut "$SHORTCUT_PATH" "org.minetest.minetest.desktop" "$EXEC_PATH" "$WORKING_DIR_PATH" "$MT_ICON" "Final Minetest"
    fi
    show_os_release
}

upgradeAndMerge(){
    # You must set the following variables or sequential parameters:
    # 1. UPGRADE_TYPE: a minetest subdirectory such as "worlds"
    # 2. INSTALL_PATH: a valid installed copy of minetest
    # 3. OLD_VERSION_PATH: a valid old installed copy of minetest
    # 4. (optional) "inplace" to copy instead of "move" and to only
    #    affect OLD_VERSION_PATH such as for:
    #    upgradeAndMerge "mods" "$INSTALL_PATH/games/Bucket_Game" "$INSTALL_PATH/games/ENLIVEN" "inplace"
    if [ ! -z "$1" ]; then
        # worlds, games, or something else
        UPGRADE_TYPE="$1"
    fi
    upgrades_base_path="$INSTALL_PATH"
    if [ ! -z "$2" ]; then
        # ~/minetest or
        upgrades_base_path="$2"
    fi
    if [ ! -z "$3" ]; then
        OLD_VERSION_PATH="$3"
    fi
    UPGRADE_MODE="move"
    if [ ! -z "$4" ]; then
        UPGRADE_MODE="$4"
    fi
    if [ ! -d "$upgrades_base_path/$UPGRADE_TYPE" ]; then
        customExit "* WARNING: The $UPGRADE_TYPE upgrade will be skipped since the UPGRADE_TYPE directory \"$UPGRADE_TYPE\" is not present in the upgrades_base_path \"$upgrades_base_path\"."
    else
        #echo "* upgrading $UPGRADE_TYPE"
        for SUB_PATH in `find $upgrades_base_path/$UPGRADE_TYPE -maxdepth 1`
        do
            SUB_NAME="`basename $SUB_PATH`"
            if [ "$SUB_PATH" = "$upgrades_base_path/$UPGRADE_TYPE" ]; then
                echo "  * upgrading $SUB_PATH..."
            elif [ -d "$SUB_PATH" ]; then
                if [ "@$QUIET" != "@true" ]; then
                    echo "    * upgrading $SUB_NAME..."
                fi
                if [ -d "$OLD_VERSION_PATH/$UPGRADE_TYPE/$SUB_NAME" ]; then
                    # Remove the old version (the one to upgrade and
                    # keep if $UPGRADE_MODE is not move, otherwise the
                    # one to upgrade and later move to upgrades_base_path!)
                    rm -Rf "$OLD_VERSION_PATH/$UPGRADE_TYPE/$SUB_NAME" || customExit "* rm -Rf \"$OLD_VERSION_PATH/$UPGRADE_TYPE/$SUB_NAME\" failed while replacing the destination."
                    if [ "@$UPGRADE_MODE" = "@move" ]; then
                        #if [ "@$QUIET" != "@true" ]; then
                        #    echo "    - moving $SUB_PATH..."
                        #fi
                        mv "$SUB_PATH" "$OLD_VERSION_PATH/$UPGRADE_TYPE/$SUB_NAME" || customExit "mv \"$SUB_PATH\" \"$OLD_VERSION_PATH/$UPGRADE_TYPE/$SUB_NAME\" failed for the SUB_PATH directory to replace the destination"
                    else
                        # echo "    - copying \"$SUB_PATH\" to \"$OLD_VERSION_PATH/$UPGRADE_TYPE/$SUB_NAME\" to replace destination..."
                        cp -R "$SUB_PATH" "$OLD_VERSION_PATH/$UPGRADE_TYPE/$SUB_NAME" || customExit "cp -R \"$SUB_PATH\" \"$OLD_VERSION_PATH/$UPGRADE_TYPE/$SUB_NAME\" failed for the SUB_PATH directory to replace the destination"
                    fi
                else
                    if [ ! -d "$OLD_VERSION_PATH/$UPGRADE_TYPE" ]; then
                        mkdir -p "$OLD_VERSION_PATH/$UPGRADE_TYPE"
                    fi
                    if [ "@$UPGRADE_MODE" = "@move" ]; then
                        #echo "    - moving $SUB_PATH..."
                        mv "$SUB_PATH" "$OLD_VERSION_PATH/$UPGRADE_TYPE/$SUB_NAME" || customExit "mv \"$SUB_PATH\" \"$OLD_VERSION_PATH/$UPGRADE_TYPE/$SUB_NAME\" for the SUB_PATH directory that was not on the destination."
                        # ^ so that rmdir doesn't fail below.
                    else
                        # echo "    - copying \"$SUB_PATH\" to \"$OLD_VERSION_PATH/$UPGRADE_TYPE/$SUB_NAME\" not on destination..."
                        cp -R "$SUB_PATH" "$OLD_VERSION_PATH/$UPGRADE_TYPE/$SUB_NAME" || customExit "mv \"$SUB_PATH\" \"$OLD_VERSION_PATH/$UPGRADE_TYPE/$SUB_NAME\" for the SUB_PATH directory that was not on the destination."
                    fi
                fi
            else
                if [ "@$QUIET" != "@true" ]; then
                    echo "    * upgrading $SUB_NAME..."
                fi
                if [ "@$UPGRADE_MODE" = "@move" ]; then
                    #if [ "@$QUIET" != "@true" ]; then
                    #    echo "    - moving $SUB_PATH..."
                    #fi
                    if [ ! -d "$OLD_VERSION_PATH/$UPGRADE_TYPE" ]; then
                        mkdir -p "$OLD_VERSION_PATH/$UPGRADE_TYPE" || customExit "mkdir -p \"$OLD_VERSION_PATH/$UPGRADE_TYPE\" failed for the SUB_PATH file on the destination."
                    fi
                    mv -f "$SUB_PATH" "$OLD_VERSION_PATH/$UPGRADE_TYPE/$SUB_NAME" || customExit "mv \"$SUB_PATH\" \"$OLD_VERSION_PATH/$UPGRADE_TYPE/$SUB_NAME\" failed for the SUB_PATH file on the destination"
                else
                    cp -f "$SUB_PATH" "$OLD_VERSION_PATH/$UPGRADE_TYPE/$SUB_NAME" || customExit "cp \"$SUB_PATH\" \"$OLD_VERSION_PATH/$UPGRADE_TYPE/$SUB_NAME\" failed for the SUB_PATH file on the destination"
                fi
            fi
        done
        if [ "@$UPGRADE_MODE" = "@move" ]; then
            rmdir "$upgrades_base_path/$UPGRADE_TYPE" || customExit "rmdir \"$upgrades_base_path/$UPGRADE_TYPE\" failed while upgrading \"$OLD_VERSION_PATH\"."
            mv "$OLD_VERSION_PATH/$UPGRADE_TYPE" "$upgrades_base_path/" || customExit "mv \"$OLD_VERSION_PATH/$UPGRADE_TYPE\" \"$upgrades_base_path/\""
            # echo "  * $OLD_VERSION_PATH/$UPGRADE_TYPE is now upgraded and moved to \"$upgrades_base_path/$UPGRADE_TYPE\"."
        #else
            #echo "  * $OLD_VERSION_PATH has been upgraded in place (\"$upgrades_base_path/$UPGRADE_TYPE\" remains untouched)."
        fi
    fi
}

copyIfExists(){
    if [ -f "$1" ]; then
        cp "$1" "$2"
    fi
}

moveIfExists(){
    if [ -f "$1" ]; then
        mv "$1" "$2"
    fi
}

moveIfExistsOrDeleteIfOnDest(){
    if [ -f "$1" ]; then
        if [ -f "$2" ]; then
            rm "$1"
        else
            mv "$1" "$2"
        fi
    fi
}

deleteIfExists(){
    if [ ! -z "$1" ]; then
        if [ -d "$1" ]; then
            rm -Rf $1
        elif [ -f "$1" ]; then
            rm $1
        fi
    else
        echo "* ERROR: No param was specified for deleteDirIfExists"
    fi
}



installOrUpgradeMinetest(){
    # You must set the following variables or sequential parameters:
    # 1. NEW_VERSION_PATH
    # 2. INSTALL_PATH
    # 3. (optional) VERSIONED_MT_PATH (a path that does not yet exist
    #    but will store the old version temporarily until user data is
    #    moved to the new version and other data is deleted).
    #    If not set, it will become $INSTALL_PATH.$new_release_version
    #    ($new_release_version must be present, and is set above by
    #    this rc file).
    if [ ! -z "$1" ]; then
        NEW_VERSION_PATH="$1"
    fi
    if [ ! -z "$2" ]; then
        INSTALL_PATH="$2"
    fi
    if [ ! -z "$3" ]; then
        VERSIONED_MT_PATH="$3"
    else
        if [ -z "$old_release_version" ]; then
            customExit "old_release_version was not detected. This should never happen (it should at least be 1st or bak or something)."
        fi
        if [ -z "$INSTALL_PATH" ]; then
            customExit "INSTALL_PATH was not detected. This should never happen."
        fi
        VERSIONED_MT_PATH="$INSTALL_PATH.$old_release_version"
        echo "  * [installOrUpgradeMinetest] using $VERSIONED_MT_PATH for remnants"
    fi
    install_dest="$INSTALL_PATH"
    # ^ make a separate variable since it will change if a symlink
    if [ -z "$this_dst_flag_path" ]; then
        this_dst_flag_path="$INSTALL_PATH/bin/minetest"
    fi

    #rsync -rt --info=progress2 "$EXTRACTED_SRC_PATH/minetest/" "$install_dest" || customExit "Cannot rsync files from installer data $EXTRACTED_SRC_PATH/minetest/ to $install_dest"
    if [ -z "$new_release_version" ]; then
        customExit "You must call detect_mt_version_at such as 'detect_mt_version_at \"$NEW_VERSION_PATH\"' before running installOrUpgradeMinetest."
    fi
    #echo "Checking $new_release_version..."
    if [ "@$new_release_version" = "@new" ]; then
        customWarn "The new version wasn't detected properly (using \"new\")"
    else
        echo "  - installing or upgrading using version $new_release_version..."
    fi

    if [ -d "$NEW_VERSION_PATH" ]; then
        virtual_dest="$install_dest"
        link_target=`readlink $virtual_dest`
        # install_dest="/tank/local/owner/minetest"
        #install_dest="$virtual_dest"
        ENABLE_RELINK=false
        if [ ! -z "$link_target" ]; then
            ENABLE_RELINK=true
            if [ ! -d "$link_target" ]; then
                customExit "The link \"$virtual_dest\" points to a directory that does not exist: \"$link_target\""
            fi
            install_dest="$link_target"
            echo "* detected that $virtual_dest is a symlink to $link_target"
            echo "  (redirecting rsync to prevent symlink to dir conversion: installing to $install_dest"
            echo "   and recreating symlink '$virtual_dest' pointing to '$install_dest')..."
        else
            echo "Installing \"$EXTRACTED_SRC_PATH/minetest\" directory as \"$install_dest\"..."
        fi


        if [ -d "$install_dest" ]; then
            if [ -z "$VERSIONED_MT_PATH" ]; then
                customExit "You must specify the VERSIONED_MT_PATH (such as \"$HOME/minetest.bak\" or another unused directory) to retain and merge the old version's user data since the old version exists."
            fi

            if [ -d "$VERSIONED_MT_PATH" ]; then
                echo "You already have an old copy of \"$VERSIONED_MT_PATH\". You must rename it if you want to reinstall without losing any extra files you may have put there before upgrading to the current version."
                return 2
            fi
            if [ ! -f "`command -v basename`" ]; then
                customExit "Install cannot continue because the basename command is not present."
            fi
            if [ ! -f "`command -v find`" ]; then
                customExit "Install cannot continue because the find command is not present."
            fi
            mv "$install_dest" "$VERSIONED_MT_PATH"
            mv "$NEW_VERSION_PATH" "$install_dest"

            #moveIfExists "$VERSIONED_MT_PATH/client/serverlist/favoriteservers.txt" "$install_dest/client/serverlist/favoriteservers.txt"
            moveIfExists "$VERSIONED_MT_PATH/client/serverlist/favoriteservers.txt" "$install_dest/client/serverlist/favoriteservers.txt"
            if [ -d "$VERSIONED_MT_PATH/client/serverlist" ]; then
                rmdir --ignore-fail-on-non-empty "$VERSIONED_MT_PATH/client/serverlist"
            fi
            upgradeAndMerge "client" "$install_dest" "$VERSIONED_MT_PATH"
            upgradeAndMerge "clientmods" "$install_dest" "$VERSIONED_MT_PATH"
            upgradeAndMerge "games" "$install_dest" "$VERSIONED_MT_PATH"
            upgradeAndMerge "worlds" "$install_dest" "$VERSIONED_MT_PATH"
            upgradeAndMerge "mods" "$install_dest" "$VERSIONED_MT_PATH"
            PREV_QUIET="$QUIET"
            QUIET=true
            upgradeAndMerge "textures" "$install_dest" "$VERSIONED_MT_PATH"
            upgradeAndMerge "media" "$install_dest/cache" "$VERSIONED_MT_PATH/cache"
            deleteIfExists "$VERSIONED_MT_PATH/media"
            QUIET="$PREV_QUIET"
            deleteIfExists "$VERSIONED_MT_PATH/minetest.conf.example"
            deleteIfExists "$VERSIONED_MT_PATH/minetest.conf.example.extra"
            deleteIfExists "$VERSIONED_MT_PATH/bin/minetest"
            deleteIfExists "$VERSIONED_MT_PATH/bin/minetestserver"
            deleteIfExists "$VERSIONED_MT_PATH/bin/minetest.bak"
            deleteIfExists "$VERSIONED_MT_PATH/bin/minetest.bin"
            deleteIfExists "$VERSIONED_MT_PATH/bin/minetestserver.bak"
            deleteIfExists "$VERSIONED_MT_PATH/bin/minetestserver.bin"
            deleteIfExists "$VERSIONED_MT_PATH/bin/debug.txt"
            rmdir --ignore-fail-on-non-empty "$VERSIONED_MT_PATH/bin"
            # upgradeAndMerge "util" "$install_dest" "$VERSIONED_MT_PATH"
            # ^ texture packs
            upgradeAndMerge "clientmods" "$install_dest" "$VERSIONED_MT_PATH"
            moveIfExistsOrDeleteIfOnDest "$VERSIONED_MT_PATH/minetest.ENLIVEN.client-example.conf" "$install_dest/minetest.ENLIVEN.client-example.conf"
            moveIfExistsOrDeleteIfOnDest "$VERSIONED_MT_PATH/minetest.ENLIVEN.LAN-client-example.conf" "$install_dest/minetest.ENLIVEN.LAN-client-example.conf"
            moveIfExistsOrDeleteIfOnDest "$VERSIONED_MT_PATH/minetest.ENLIVEN.server-example.conf" "$install_dest/minetest.ENLIVEN.server-example.conf"
            moveIfExists "$VERSIONED_MT_PATH/minetest.conf" "$install_dest/minetest.conf"
            moveIfExists "$VERSIONED_MT_PATH/arrowkeys.txt" "$install_dest/arrowkeys.txt"
            moveIfExists "$VERSIONED_MT_PATH/.saved_passwords" "$install_dest/.saved_passwords"
            OLD_BIN_PATH="$VERSIONED_MT_PATH/bin"
            NEW_BIN_PATH="$install_dest/bin"
            # See <https://unix.stackexchange.com/questions/87456/shell-script-to-check-for-the-presence-of-one-or-more-files-with-a-specific-exte>
            if ls ${OLD_BIN_PATH}/*.png &>/dev/null
            then
                echo "  * moving png screenshots..."
                mv ${OLD_BIN_PATH}/*.png ${NEW_BIN_PATH}/
            else
                echo "  * You have no png files in ${OLD_BIN_PATH}."
            fi
            if ls ${OLD_BIN_PATH}/*.jpg &>/dev/null
            then
                echo "  * moving jpg screenshots..."
                mv ${OLD_BIN_PATH}/*.jpg ${NEW_BIN_PATH}/
            else
                echo "  * You have no jpg files in ${OLD_BIN_PATH}."
            fi
            deleteIfExists "$VERSIONED_MT_PATH/builtin"
            rmdir --ignore-fail-on-non-empty "$VERSIONED_MT_PATH/cache"
            deleteIfExists "$VERSIONED_MT_PATH/doc"
            deleteIfExists "$VERSIONED_MT_PATH/fonts"
            deleteIfExists "$VERSIONED_MT_PATH/locale"
            deleteIfExists "$VERSIONED_MT_PATH/misc"
            deleteIfExists "$VERSIONED_MT_PATH/po"
            deleteIfExists "$VERSIONED_MT_PATH/solib"
            deleteIfExists "$VERSIONED_MT_PATH/sounds"
            deleteIfExists "$VERSIONED_MT_PATH/util"
            deleteIfExists "$VERSIONED_MT_PATH/LICENSE.txt"
            deleteIfExists "$VERSIONED_MT_PATH/release.txt"
            deleteIfExists "$VERSIONED_MT_PATH/readme.txt"
            rmdir --ignore-fail-on-non-empty "$VERSIONED_MT_PATH/bin"
            rmdir --ignore-fail-on-non-empty "$VERSIONED_MT_PATH"
        else
            mv "$NEW_VERSION_PATH" "$install_dest"
        fi

        if [ "@$ENABLE_RELINK" = "@true" ]; then
            if [ ! -d "$dest_programs/minetest" ]; then
                echo "* removing old symlink $virtual_dest..."
                rm "$virtual_dest" || customExit "Removing the old symlink failed: rm \"$virtual_dest\"."
                echo "* creating new symlink to $install_dest directory as $virtual_dest..."
                ln -s "$install_dest" "$virtual_dest"
            fi
        fi

        if [ ! -f "$this_dst_flag_path" ]; then
            customExit "ERROR: not complete--couldn't install binary as '$this_dst_flag_path'"
        fi
        # curl https://downloads.minetest.org/release.txt -o "$install_dest/release.txt"
    else
        customExit "There is no minetest directory $NEW_VERSION_PATH."
    fi
    if [ "@$new_release_version" != "@new" ]; then
        echo "Release $new_release_version" > "$install_dest/release.txt"
        echo "  * wrote \"`cat $install_dest/release.txt`\" to \"$install_dest/release.txt\"."
    fi
    return 0
}

minimize_mod() {
    MTMOD_DEST_PATH=$1
    MTMOD_DEST_NAME="a"
    if [ ! -z "$2" ]; then
        MTMOD_DEST_NAME=$2
    fi
    if [ ! -d "$MTMOD_DEST_PATH" ]; then
        echo "  [minetestenv-in-place minimize_mod] ERROR: $MTMOD_DEST_PATH is missing."
        return 1
    fi
    if [ -d "$MTMOD_DEST_PATH/.git" ]; then
        rm -Rf "$MTMOD_DEST_PATH/.git"
    fi
    if [ -f "$MTMOD_DEST_PATH/.gitignore" ]; then
        rm -Rf "$MTMOD_DEST_PATH/.gitignore"
    fi
    # remove etc to make users downloading mods faster:
    if [ -d "$MTMOD_DEST_PATH/etc" ]; then
        echo "    optimizing $MTMOD_DEST_NAME mod: removing non-game data at $MTMOD_DEST_PATH/etc..."
        rm -Rf "$MTMOD_DEST_PATH/etc"
    fi
    if [ -d "$MTMOD_DEST_PATH/projects" ]; then
        rm -Rf "$MTMOD_DEST_PATH/projects"
        echo "    optimizing $MTMOD_DEST_NAME mod: removing non-game data at $MTMOD_DEST_PATH/projects..."
    fi
    if [ -d "$MTMOD_DEST_PATH/src" ]; then
        if [ -z "`ls $MTMOD_DEST_PATH/src/*.lua`" ]; then
            rm -Rf "$MTMOD_DEST_PATH/src"
            echo "    optimizing $MTMOD_DEST_NAME mod: removing non-game data at $MTMOD_DEST_PATH/src since it contains no lua files..."
        fi
    fi
    for EXTRA_NAME in screenshot.png screenshot.jpg screenshot.bmp screenshot.tif screenshot.gif
    do
        # if ls ${MTMOD_DEST_PATH}/*.png &>/dev/null
        if [ -f "$MTMOD_DEST_PATH/$EXTRA_NAME" ]; then
            echo "    optimizing $MTMOD_DEST_NAME mod: removing $MTMOD_DEST_PATH/$EXTRA_NAME..."
            rm -f "$MTMOD_DEST_PATH/$EXTRA_NAME"
        fi
    done
}

if [ "@$EM_ONLINE" = "@" ]; then
    EM_ONLINE="true"
fi

install_git_mod_here(){
    PREV_DIR="`pwd`"
    THIS_MODS_PATH="`pwd`"
    git_url="$1"
    mod_name="$2"
    if [ -z "$git_url" ]; then
        customExit "  * ERROR: install_git_mod_here requires a URL."
    fi
    if [ -z "$mod_name" ]; then
        customExit "  * ERROR: install_git_mod_here requires a mod name as the second parameter."
    fi
    MTMOD_DEST_PATH="$THIS_MODS_PATH/$mod_name"

    if [ ! -d "$GIT_REPOS_PATH" ]; then
        mkdir -p "$GIT_REPOS_PATH"
    fi
    THIS_MOD_REPO="$GIT_REPOS_PATH/$mod_name"

    if [ -d "$MTMOD_DEST_PATH/.git" ]; then
        if [ ! -d "$THIS_MOD_REPO" ]; then
            # Deal with remnants from old versions of this function
            # that left git metadata in the mod directory.
            mv "$MTMOD_DEST_PATH" "$THIS_MOD_REPO"
        fi
    fi
    if [ ! -d "$THIS_MOD_REPO" ]; then
        git clone "$git_url" "$THIS_MOD_REPO"
    else
        cd "$THIS_MOD_REPO" || customExit "(install_git_mod_here) 'cd \"$THIS_MOD_REPO\"' failed in '`pwd`'"
        # echo "  * updating '`pwd`' from git..."
        if [ "@$EM_ONLINE" != "@false" ]; then
            GIT_OUTPUT=$(git pull)
            if [ "$GIT_OUTPUT" != "Already up to date." ]; then
                echo "  $GIT_OUTPUT"
            fi
            if [ $? -ne 0 ]; then
                echo "WARNING: (install_git_mod_here) 'git pull' failed in '`pwd`'"
            fi
        fi
    fi

    cd "$PREV_DIR" || customExit "(install_git_mod_here) 'cd ..' failed in '`pwd`'"

    if [ -d "$THIS_MOD_REPO" ]; then
        echo "  * updating $mod_name from $THIS_MOD_REPO..."
        if [ -f "`command -v rsync`" ]; then
            rsync -rt "$THIS_MOD_REPO/" "$MTMOD_DEST_PATH"
        else
            echo "    removing old `pwd`/$mod_name since rsync is not present..."
            rm -Rf "$MTMOD_DEST_PATH" || customExit "rm -Rf \"$MTMOD_DEST_PATH\" failed."
            cp -R "$THIS_MOD_REPO" "$MTMOD_DEST_PATH" || customExit "cp -R \"$THIS_MOD_REPO\" \"$MTMOD_DEST_PATH\" failed."
        fi
        minimize_mod "$MTMOD_DEST_PATH"
    else
        customExit "  * ERROR: Creating $THIS_MOD_REPO failed."
    fi
}

show_os_release(){
    if [ -f "/etc/os-release" ]; then
        #if [ -z "$NAME" ]; then
        source /etc/os-release
        echo
        echo "Your operating system is $NAME $VERSION"
        #fi
    fi
}

addEnlivenMinetestPatches(){
    # REPO_PATH is determined above.
    if [ ! -z "$1" ]; then
        install_dest="$1"
    fi
    if [ -z "$REPO_PATH" ]; then
        customExit "[$addEnlivenMinetestPatches] The REPO_PATH is not set."
    fi
    if [ ! -d "$REPO_PATH" ]; then
        customExit "[$addEnlivenMinetestPatches] The REPO_PATH does not exist: \"$REPO_PATH\""
    fi
    if [ -z "$PATCHES_PATH" ]; then
        PATCHES_PATH="$REPO_PATH/patches"
    fi
    if [ ! -d "$PATCHES_PATH" ]; then
        customExit "The PATCHES_PATH does not exist: \"$PATCHES_PATH\""
    fi
    if [ ! -d "$install_dest" ]; then
        customExit "The install_dest does not exist: \"$install_dest\""
    fi
    src_menu="$PATCHES_PATH/subgame/menu"
    dst_menu="$install_dest/games/ENLIVEN/menu"
    echo "updating '$dst_menu' from '$src_menu/'..."
    if [ -f "`command -v rsync`" ]; then
        rsync -rt "$src_menu/" "$dst_menu"
    else
        echo "* WARNING: rsync is missing, so patching ENLIVEN/menu from \"$src_menu\" is being skipped."
        cp -f "$src_menu/header.png" "$dst_menu/"
        cp -f "$src_menu/menu.png" "$dst_menu/"
    fi
    echo "name = ENLIVEN" > "$install_dest/games/ENLIVEN/game.conf"
    src_game="$PATCHES_PATH/Bucket_Game-patched"
    dst_game="$install_dest/games/ENLIVEN"
    echo "updating '$dst_game' from '$src_game/'..."
    if [ -f "`command -v rsync`" ]; then
        rsync -rt "$src_game/" "$dst_game"
    else
        echo "* WARNING: rsync is missing, so patching ENLIVEN from \"$src_game\" is being skipped."
    fi
    if [ -d "$dst_game/mods/coderfood/food_basic/etc" ]; then
        rm -Rf "$dst_game/mods/coderfood/food_basic/etc"
    fi

    minetest_conf_dest="$install_dest/minetest.conf"
    game_minetest_conf_dest="$install_dest/games/ENLIVEN/minetest.conf"

    # Bucket_Game doesn't come with a minetest.conf, only minetest.conf.example* files
    # if [ ! -f "$install_dest/minetest.Bucket_Game-example.conf" ]; then
    #     cp -f "$$minetest_conf_dest" "$install_dest/minetest.Bucket_Game-example.conf"
    # fi

    client_example_dest="$install_dest/minetest.ENLIVEN.client-example.conf"

    echo "Installing minetest.ENLIVEN.*-example.conf files..."
    cp -f "$PATCHES_PATH/subgame/minetest.LAN-client-example.conf" "$install_dest/minetest.ENLIVEN.LAN-client-example.conf" || customExit "Cannot copy minetest.ENLIVEN.LAN-client-example.conf"
    cp -f "$PATCHES_PATH/subgame/minetest.server-example.conf"     "$install_dest/minetest.ENLIVEN.server-example.conf" || customExit "Cannot copy minetest.ENLIVEN.server-example.conf"
    cp -f "$PATCHES_PATH/subgame/minetest.client-example.conf"     "$install_dest/minetest.ENLIVEN.client-example.conf" || customExit "Cannot copy minetest.ENLIVEN.client-example.conf"

    echo "Writing '$game_minetest_conf_dest'..."
    cp -f "$PATCHES_PATH/subgame/minetest.conf" "$game_minetest_conf_dest"

    # client conf writing only ever happens once, unless you manually delete $minetest_conf_dest:
    if [ ! -f "$minetest_conf_dest" ]; then
        # if [ -f "$minetest_conf_dest" ]; then
            # echo "Backing up minetest.conf..."
            # if [ ! -f "$minetest_conf_dest.1st" ]; then
                # cp -f "$minetest_conf_dest" "$minetest_conf_dest.1st"
            # else
                # cp -f "$minetest_conf_dest" "$minetest_conf_dest.bak"
            # fi
        # fi
        echo "Writing minetest.conf (client region)..."
        cp -f "$PATCHES_PATH/subgame/minetest.client-example.conf" "$minetest_conf_dest"  || customExit "Cannot copy minetest.client-example.conf to $minetest_conf_dest"
        echo "Appending example settings (server region) to '$minetest_conf_dest'..."
        cat "$PATCHES_PATH/subgame/minetest.server-example.conf" >> "$minetest_conf_dest" || customExit "Cannot append minetest.server-example.conf"
    else
        echo "$minetest_conf_dest exists (remove it if you want the installer to write an example version)"
    fi


    if [ -f "$minetest_conf_dest" ]; then
        cat << END

NOTE: minetest.org releases allow you to put a world.conf file in your
  world, so that is the file you should edit manually in your world
  --this installer overwrites $minetest_conf_dest and
  worlds/CenterOfTheSun settings (the author Poikilos' world).
  Continue to place server settings such as announce in
  $minetest_conf_dest.
  Leave $game_minetest_conf_dest intact, as it defines the game.
  If you have suggestions for changes or configurability, please use the
  issue tracker at <https://github.com/poikilos/EnlivenMinetest>.

END
    fi


    world_override_src="$REPO_PATH/overrides/CenterOfTheSun/minetest/worlds/CenterOfTheSun"
    world_override_dst="$HOME/.minetest/worlds/CenterOfTheSun"
    world_override_dst="$HOME/.minetest/worlds/CenterOfTheSun"
    try_world_override_dst="$HOME/minetest/worlds/CenterOfTheSun"
    if [ -d "$try_world_override_dst" ]; then
        world_override_dst="$try_world_override_dst"
    fi
    world_conf_src="$world_override_src/world.conf"
    world_conf_dst="$world_override_dst/world.conf"
    world_mt_src="$world_override_src/world.mt"
    world_mt_dst="$world_override_dst/world.mt"
    override_more="$REPO_PATH/overrides/CenterOfTheSun/games/ENLIVEN"
    appends="$REPO_PATH/overrides/CenterOfTheSun/append"
    minetest_conf_append="$appends/minetest.conf"
    if [ -d "$world_override_dst" ]; then
        echo "You have the CenterOfTheSun world. Listing any changes..."
        if [ -f "$world_conf_src" ]; then
            if [ -f "$world_conf_dst" ]; then
                echo " * overwrite $world_conf_dst with $world_conf_src"
            else
                echo " * add the world.conf from $world_conf_src"
            fi
            cp -f "$world_conf_src" "$world_conf_dst"
        fi
        if [ -z "`grep 'region overrides/CenterOfTheSun/append' $minetest_conf_dest`" ]; then
            if [ -f "$minetest_conf_append" ]; then
                cat "$minetest_conf_append" >> "$minetest_conf_dest"
            fi
        fi
    fi

    if [ "@$ENABLE_CLIENT" = "@true" ]; then
        #params: _SRC_SHORTCUT_PATH, _DST_SHORTCUT_NAME, _EXEC, _WORKING_DIR, _ICON, _CAPTION:
        SHORTCUT_PATH="$PATCHES_PATH/deploy-patched/misc/org.minetest.minetest.desktop"
        EXEC_PATH="$install_dest/bin/minetest"
        WORKING_DIR_PATH="$install_dest/bin"
        MT_ICON="$install_dest/misc/minetest-xorg-icon-128.png"
        install_shortcut "$SHORTCUT_PATH" "org.minetest.minetest.desktop" "$EXEC_PATH" "$WORKING_DIR_PATH" "$MT_ICON" "Final Minetest"
    fi

    if [ -f "`command -v rsync`" ]; then
        if [ -f $install_dest/games/ENLIVEN/mods/codermobs/codermobs/animal_materials.lua ]; then
            if [ -d $PATCHES_PATH/mods-stopgap/animal_materials_legacy ]; then
                echo "* installing animal_materials_legacy (only needed for worlds created with old versions of Bucket_Game)"
                rsync -rt $PATCHES_PATH/mods-stopgap/animal_materials_legacy $install_dest/games/ENLIVEN/mods/
            else
                echo "* MISSING $PATCHES_PATH/mods-stopgap/animal_materials"
            fi
        else
            echo "* SKIPPING a stopgap mod since no animal_materials"
        fi

        if [ -f $install_dest/games/ENLIVEN/mods/codermobs/codermobs/elk.lua ]; then
            if [ -d $PATCHES_PATH/mods-stopgap/elk_legacy ]; then
                echo "* installing elk_legacy (only needed for worlds created with old versions of Bucket_Game)"
                rsync -rt $PATCHES_PATH/mods-stopgap/elk_legacy $install_dest/games/ENLIVEN/mods/
            else
                echo "* MISSING $PATCHES_PATH/mods-stopgap/elk_legacy"
            fi
        else
            echo "* SKIPPING a stopgap mod since no elk.lua"
        fi

        if [ -d "$install_dest/games/ENLIVEN/mods/coderbuild/nftools" ]; then
            if [ -d $PATCHES_PATH/mods-stopgap/nftools_legacy ]; then
                echo "* installing nftools_legacy (only needed for worlds created with old versions of Bucket_Game)"
                rsync -rt $PATCHES_PATH/mods-stopgap/nftools_legacy $install_dest/games/ENLIVEN/mods/
            else
                echo "* MISSING $PATCHES_PATH/mods-stopgap/nftools_legacy"
            fi
        else
            echo "* SKIPPING a stopgap mod since no nftools"
        fi
    else
        echo "* WARNING: rsync is missing, so adding mods from \"$PATCHES_PATH/mods-stopgap\" to ENLIVEN/mods is being skipped."
    fi
}

analyzeGameSettings() {
    if [ ! -z "$1" ]; then
        THIS_GAME_PATH=$1
    fi
    if [ ! -d "$THIS_GAME_PATH" ]; then
        customExit "  [$MT_ENV_RUP_NAME: analyzeGameSettings] THIS_GAME_PATH \"$THIS_GAME_PATH\" is not present."
    fi
    this_dumps_name="`basename $THIS_GAME_PATH`"
    this_dumps_path="$EM_CACHE_PATH/$this_dumps_name"
    if [ ! -d "$this_dumps_path" ]; then
        mkdir -p "$this_dumps_path"
    fi
    settings_dump="$this_dumps_path/settings-dump.txt"
    settings_types_list="$this_dumps_path/settingtypes-list.txt"
    if [ ! -f "$settings_dump" ]; then
        echo "  - Creating $settings_dump..."
        grep -r "$THIS_GAME_PATH" -e "setting_get" > $settings_dump
        grep -r "$THIS_GAME_PATH" -e "minetest.settings:get" >> $settings_dump
    else
        echo "  - $settings_dump was already created"
    fi
    if [ ! -f "$settings_types_list" ]; then
        echo "  - creating $settings_types_list..."
        find "$THIS_GAME_PATH" -name "settingtypes.txt" > $settings_types_list
    else
        echo "  - $settings_types_list was already created"
    fi
}

installOrUpgradeENLIVEN() {
    PREV_DIR="`pwd`"
    # REPO_PATH is detected above.
    if [ -z "$REPO_PATH" ]; then
        customExit "[installOrUpgradeENLIVEN] The REPO_PATH is not set."
    fi
    if [ ! -d "$REPO_PATH" ]; then
        echo "  * INFO: [installOrUpgradeENLIVEN] Installing ENLIVEN to games will be skipped since you are not using \"$REPO_PATH\""
        return 2
    fi
    if [ ! -z "$1" ]; then
        install_dest="$1"
    fi
    if [ ! -d "$install_dest" ]; then
        customExit "[installOrUpgradeENLIVEN] The install_dest is missing: \"$install_dest\""
    fi
    dest_official_game="$install_dest/games/Bucket_Game"
    dest_enliven="$install_dest/games/ENLIVEN"
    if [ ! -d "$dest_official_game" ]; then
        customExit "[installOrUpgradeENLIVEN] \"$dest_official_game\" is missing."
    fi
    if [ ! -d "$dest_enliven" ]; then
        echo "Copying $dest_official_game to $dest_enliven..."
        cp -R "$dest_official_game" "$dest_enliven"
    else
        if [ -d "$dest_enliven" ]; then
            if [ -d "$dest_official_game" ]; then
                echo "* upgrading $dest_enliven components using $dest_official_game..."
                upgradeAndMerge "mods" "$dest_official_game" "$dest_enliven" "inplace"
            else
                echo "* WARNING: Upgrading ENLIVEN is not possible since $dest_official_game is not present."
            fi
        fi
    fi
    dest_enliven_mods="$dest_enliven/mods"
    enliven_warning=""
    if [ -d "$dest_enliven_mods" ]; then
        cd "$dest_enliven_mods" || customExit "[installOrUpgradeENLIVEN] 'cd \"$dest_enliven_mods\"' failed."
        # install_git_mod_here https://github.com/BenjieFiftysix/sponge.git sponge
        install_git_mod_here https://github.com/poikilos/metatools.git metatools
        install_git_mod_here https://github.com/MinetestForFun/fishing.git fishing
        install_git_mod_here https://github.com/minetest-mods/throwing.git throwing
        install_git_mod_here https://github.com/minetest-mods/ccompass.git ccompass
        install_git_mod_here https://github.com/minetest-mods/throwing_arrows.git throwing_arrows
    else
        enliven_warning="$enliven_warning* WARNING: Installing ENLIVEN mods was skipped since '$dest_enliven_mods' does not exist."
    fi
    cd "$PREV_DIR"
    # PATCHES_DIR_NAME="patches"
    PATCHES_PATH="$REPO_PATH/patches"
    if [ -d "$PATCHES_PATH" ]; then
        #pushd "$REPO_PATH"
        addEnlivenMinetestPatches "$install_dest"
        #popd
    else
        cat <<END
    $PATCHES_PATH is missing. To fix this, set:

        REPO_PATH=$HOME/git/EnlivenMinetest
        # in \"$scripting_rc_path\" or the environment.
END
    fi
}

detect_installed_mt_version(){
    if [ ! -z "$1" ]; then
        BACKUP_NAME_1="$1"
    fi
    if [ ! -z "$2" ]; then
        BACKUP_NAME_2="$2"
    fi
    if [ -z "$INSTALL_PATH" ]; then
        customExit "[detect_installed_mt_version] INSTALL_PATH is missing"
    fi
    old_release_line=
    old_release_version=
    if [ -f "$INSTALL_PATH/release.txt" ]; then
        old_release_line="`cat $INSTALL_PATH/release.txt | grep Release`"
    fi
    backup_msg=
    if [ ! -z "$old_release_line" ]; then
        old_release_version="${old_release_line##* }"  # get second word
        backup_msg="  - using \"$INSTALL_PATH.$old_release_version\" for storing remnants."
    else
        if [ ! -z "$BACKUP_NAME_1" ]; then
            old_release_version="$BACKUP_NAME_1"
            if [ -d "$INSTALL_PATH.$old_release_version" ]; then
                if [ ! -z "$BACKUP_NAME_2" ]; then
                    old_release_version="$BACKUP_NAME_2"
                #    echo "    - old_release_version:'$old_release_version'"
                #else
                #    echo "    - there is no second choice for the version."
                fi
            fi
            backup_msg="    * using \"$INSTALL_PATH.$old_release_version\" instead of version for storing remnants since $INSTALL_PATH does not contain release.txt."
        fi
    fi
    if [ ! -z "$backup_msg" ]; then
        if [ -d "$INSTALL_PATH" ]; then
            echo "$backup_msg"
        fi
    fi
}

detect_mt_version_at(){
    # Sequential params:
    # 1. (required) path to a minetest directory (the new one!)
    # 2. (optional) a url to a release.txt file to use if the version
    #    is not detected by other means.
    # 3. (optional) the default version to set if no version is detected
    #    (if blank, exit script on failure)
    this_err=""
    new_release_line=
    new_release_version=
    if [ -z "$1" ]; then
        echo "You must set param 1 which is the new minetest directory"
    fi
    VERSION_ORIGIN="$1/release.txt"
    if [ ! -f "$1/release.txt" ]; then
        if [ ! -z "$2" ]; then
            curl $RELEASE_TXT_URL -o "$1/release.txt" || this_err="curl $RELEASE_TXT_URL failed."
            VERSION_ORIGIN="$RELEASE_TXT_URL"
        fi
    fi
    if [ -f "$1/release.txt" ]; then
        new_release_line="`cat $1/release.txt | grep Release`"
        if [ ! -z "$new_release_line" ]; then
            new_release_version="${new_release_line##* }"  # get second word
        else
            if [ -f "$1/release.txt" ]; then
                cat "$1/release.txt"
                this_err="Obtaining a Release line from $VERSION_ORIGIN failed (got '$new_release_line')."
            fi
        fi
    else
        if [ -z "$this_err" ]; then
            this_err="\"$1/release.txt\" does not exist."
        fi
    fi
    version_len=${#new_release_version}
    if [ "$version_len" -ne "6" ]; then
        if [ -z "$this_err" ]; then
            this_err="Unexpected version scheme (not 6 characters): '$new_release_version' near '$new_release_line' in file $release_txt_path"
        fi
        if [ -z "$3" ]; then
            customExit "$this_err"
        else
            new_release_version="$3"
            customWarn "$this_err (Therefore, the new_release_version will be: \"$new_release_version\")"
        fi
    fi

}
INSTALL_PATH="$HOME/minetest"
detect_installed_mt_version
# ^ you must run it again with params such as "1st" "bak" to force install without knowing the old version.