alias m := mount
alias u := unmount

MOUNTPOINT := "./mnt" # where the encrypted filesystem can be accessed
VOLUME_NAME := "portable_luks_volume" # how the image should be named
IMAGE_PATH := "./luks_container.img" # path where the image should be
IMAGE_SIZE := "1G" # size how big the image should be
required_deps := 'cryptsetup fallocate mkfs.ext4 zstd mount umount chown rmdir mkdir xxhsum' # required dependencies
CHECKSUM := "xxh.checksum"

default: mount

# mounting the encrypted volume
mount: check-deps verify-checksum decompress
    @echo "creating mountpoint"
    @mkdir -p {{MOUNTPOINT}} # creating mountpoint
    sudo cryptsetup luksOpen {{IMAGE_PATH}} {{VOLUME_NAME}} # opening the luks container
    sudo mount /dev/mapper/{{VOLUME_NAME}} {{MOUNTPOINT}} # mounting the filesystem
    sudo chown $USER {{MOUNTPOINT}} # setting permission for the current user to access the mount

# unmounting the encrypted volume
unmount: check-deps
    sudo umount {{MOUNTPOINT}} # unmounting the filesystem
    sudo cryptsetup luksClose {{VOLUME_NAME}} # closing the luks container
    rmdir {{MOUNTPOINT}} # removing the mountpoint
    just compress # compressing the image

# creating an encrypted volume and mounting it
create: check-deps
    sudo fallocate -l {{IMAGE_SIZE}} {{IMAGE_PATH}} # allocating the file
    sudo cryptsetup luksFormat {{IMAGE_PATH}} {{VOLUME_NAME}} # formating the file for luks
    sudo cryptsetup luksOpen {{IMAGE_PATH}} {{VOLUME_NAME}} # opening the luks container
    sudo mkfs.ext4 /dev/mapper/{{VOLUME_NAME}} # formatting the container with a filesystem
    mkdir -p {{MOUNTPOINT}} # creating a mountpoint
    sudo mount /dev/mapper/{{VOLUME_NAME}} {{MOUNTPOINT}} # mounting filesystem


# compressing the image
compress:
    @echo "Compressing the image and removing the original"
    zstd --rm --adapt {{IMAGE_PATH}}

# decompressing the image
decompress:
    @echo "Decompressing the image and removing compressed version"
    zstd --rm -d {{IMAGE_PATH}}.zst

create-checksum:
  @xxhsum {{IMAGE_PATH}}.zst > {{CHECKSUM}} 

verify-checksum:
  @xxhsum -c {{CHECKSUM}}


# Check if all required dependencies are installed
check-deps:
    #!/usr/bin/env sh
    missing_deps=""
    # Loop through each dependency in the list
    for dep in {{required_deps}}; do
        # Check if the command exists in the PATH
        if ! command -v "$dep" > /dev/null 2>&1; then
            # If not found, add it to the list of missing dependencies (with a space separator)
            missing_deps="$missing_deps $dep"
        fi
    done

    # Check if the missing_deps variable has content (trim whitespace first)
    if [ -n "$(echo $missing_deps | xargs)" ]; then
        echo "Error: The following required dependencies are missing:" >&2
        # Use xargs to print each missing dependency on a new line, prefixed with ' - '
        echo "$missing_deps" | xargs -n1 printf " - %s\n" >&2
        echo "Please install them and try again." >&2
        # Exit with a non-zero status code to indicate failure
        exit 1
    else
        # Optional: message indicating success
        echo "All dependencies satisfied."
    fi