packageListTool

#!/bin/sh

# shellcheck disable=SC2046
# shellcheck disable=SC3037

SCRIPT_NAME=$0
SCRIPT_ARGS_STR="$*"

usage() {
    echo "Simple Package Backup for most distros"
    echo "Usage: $SCRIPT_NAME [-f filename] [-p packageManager] <save|restore>"
    echo "  -f: Optional filename (default: packages.list)"
    echo "  -p: Optional package manager (options: apt, dnf, yum, pacman, yay, paru, zypper, apk)"
    echo "  Command must be 'save' or 'restore'"
    exit 1
}

filename="packages.list"
package_manager=""

while [ $# -gt 0 ]; do
    case "$1" in
        -f)
            shift
            [ $# -eq 0 ] && usage
            filename="$1"
            ;;
        -p)
            shift
            [ $# -eq 0 ] && usage
            package_manager="$1"
            ;;
        -*)
            echo "Invalid option: $1" >&2
            usage
            ;;
        *)
            if [ -z "$command" ]; then
                command="$1"
            else
                usage
            fi
            ;;
    esac
    shift
done

# Check for exactly one command argument
if [ -z "$command" ]; then
    usage
fi

case "$command" in
    save|restore)
        # Validate command
        ;;
    *)
        usage
        ;;
esac

detect_pm() {
    if command -v yay >/dev/null 2>&1; then
        echo "yay"
    elif command -v paru >/dev/null 2>&1; then
        echo "paru"
    elif command -v pacman >/dev/null 2>&1; then
        echo "pacman"
    elif command -v apt >/dev/null 2>&1; then
        echo "apt"
    elif command -v dnf >/dev/null 2>&1; then
        echo "dnf"
    elif command -v yum >/dev/null 2>&1; then
        echo "yum"
    elif command -v zypper >/dev/null 2>&1; then
        echo "zypper"
    elif command -v apk >/dev/null 2>&1; then
        echo "apk"
    elif command -v flatpak >/dev/null 2>&1; then
        echo "flatpak"
    else
        echo "Unsupported package manager detected."
        exit 1
    fi
}

handle_package_manager() {
    # Handle save or restore based on package manager
    case $1 in
        apt) # Debian / Ubuntu
            if [ "$command" = "save" ]; then
                apt-mark showmanual | sort > "$filename"
            else
                sudo apt update
                sudo apt install -y $(cat "$filename")
            fi
            ;;
        dnf) # Red Hat
            if [ "$command" = "save" ]; then
                dnf history userinstalled | tail -n +3 | grep -v '^@' | sort > "$filename"
            else
                sudo dnf install -y $(cat "$filename")
            fi
            ;;
        yum) # Red Hat (Legacy)
            if [ "$command" = "save" ]; then
                yum list installed | tail -n +2 | awk '{print $1}' > "$filename"
            else
                sudo yum install -y $(cat "$filename")
            fi
            ;;
        yay) # AUR
            if [ "$command" = "save" ]; then
                yay -Qem | awk '{print $1}' | sort > "$filename"
            else
                yay -S --needed --noconfirm $(cat "$filename")
            fi

            printf "%bThis action is only for %s...%b\n" "${YELLOW}" "$1" "${RESET}"
            printf "Run again specifying 'pacman' as the package manager:%b\n" "${RESET}"
            printf "\t%s %s -p pacman\n" "$SCRIPT_NAME" "$SCRIPT_ARGS_STR"
            ;;
        paru) # AUR
            if [ "$command" = "save" ]; then
                paru -Qem | awk '{print $1}' | sort > "$filename"
            else
                paru -S --needed --noconfirm $(cat "$filename")
            fi

            printf "%bThis action is only for %s...%b\n" "${YELLOW}" "$1" "${RESET}"
            printf "Run again specifying 'pacman' as the package manager:%b\n" "${RESET}"
            printf "\t%s %s -p pacman\n" "$SCRIPT_NAME" "$SCRIPT_ARGS_STR"
            ;;
        pacman) # Arch
            if [ "$command" = "save" ]; then
                pacman -Qe | awk '{print $1}' | sort > "$filename"
            else
                sudo pacman -S --needed --noconfirm $(cat "$filename")
            fi
            ;;
        zypper) # openSUSE
            if [ "$command" = "save" ]; then
                zypper se -si -t package | grep '^i+ ' | awk -F '|' '{gsub(/^[ \t]+|[ \t]+$/, "", $2); print $2}' | sort > "$filename"
            else
                sudo zypper install --no-confirm $(cat "$filename")
            fi
            ;;
        apk) # Alpine
            if [ "$command" = "save" ]; then
		cat /etc/apk/world > "$filename"
            else
		doas apk add $(cat "$filename")
            fi
            ;;
        flatpak) # Flatpak
            if [ "$command" = "save" ]; then
                flatpak list --app --columns=application | tail -n +2 | sort > "$filename"
            else
                sudo flatpak install --noninteractive $(cat "$filename")
            fi
            ;;
        *)
            echo "Error: Invalid package manager '$PM'."
            exit 1
            ;;
    esac

    if [ $? = 0 ]; then
        if [ "$command" = "save" ]; then
            echo "Installed packages saved to $filename"
        else
            echo "Packages restored from $filename"
        fi
    else
        echo "Failed to perform command!"
        exit 99
    fi
}

validate_package_manager() {
    # If Package Manager is explicitly specified, validate it!
    if [ -n "$package_manager" ]; then
        if ! command -v "$package_manager" >/dev/null 2>&1; then
            printf "%sError: Specified Package Manager '%s' is not installed.%s\n" "${RED}" "$package_manager" "${RESET}"
            exit 1
        fi
        PM="$package_manager"
        echo "Using supplied Package Manager: ${PM}"
    # Not given, detect it...
    else
        PM=$(detect_pm)
        echo "Detected Package Manager: ${PM}"
    fi

    if [ "$command" = "restore" ] && [ ! -f "$filename" ]; then
        echo "Error: File '$filename' not found."
        exit 1
    fi
}

validate_package_manager
handle_package_manager "$PM"