burniso

#!/usr/bin/env bash

# ┏┓ ╻ ╻┏━┓┏┓╻╻┏━┓┏━┓
# ┣┻┓┃ ┃┣┳┛┃┗┫┃┗━┓┃ ┃
# ┗━┛┗━┛╹┗╸╹ ╹╹┗━┛┗━┛
#
# script for burning iso images to usb devices using `dd`

PROG="${0##*/}"
DEPS=(fdisk dd realpath)
declare -a ARGS=(bs=4M status=progress oflag=sync)

# colors
BLUE=$(tput setaf 4)
CYAN=$(tput setaf 6)
GRAY=$(tput setaf 8)
GREEN=$(tput setaf 2)
RED=$(tput setaf 1)
YELLOW=$(tput setaf 3)

# style
BOLD=$(tput bold)
NC="$(tput sgr0)"

function usage {
    printf "usage: %s <iso> <device>\n" "$PROG"
}

function logerr {
    local msg="$1"
    printf "%s: %s\n" "$PROG" "$msg" >&2
    exit 1
}

function confirm {
    local answer
    echo -n "Are you sure you want to continue? ${GRAY}[y/N]:${NC} "
    read -r answer

    case "$answer" in
    y | Y) return 0 ;;
    n | N) return 1 ;;
    *) return 1 ;;
    esac
}

function show_dev_info {
    local device="$1"

    [[ -z "$device" ]] && {
        usage
        logerr "err device not provided"
    }

    if [[ ! -b "$device" ]]; then
        logerr "invalid device: '$device'"
    fi

    echo -e "${GREEN}${BOLD}$device${NC} information\n"
    if ! sudo fdisk -l "$device"; then
        return 1
    fi

    return 0
}

function show_warning {
    echo -en "\n${YELLOW}${BOLD}Warning${NC}:"
    echo -e "${RED}${BOLD} device will be completely overwritten!${NC}\n"
}

function getsize {
    local file="$1"

    if [[ ! -f "$file" ]]; then
        logerr "file not found: '$file'"
    fi

    size=$(du -b "$file" | awk '{printf "%.1f", $1 / (1024 * 1024) / 1024}')
    echo "${size}GB"
}

function show_status {
    local iso="$1"
    local device="$2"

    echo "${GREEN}${BOLD}Status:${NC}"
    echo "  ${CYAN}${BOLD}Device:${NC}  ${BOLD}$device${NC}"
    echo "  ${BLUE}${BOLD}Path:${NC}    $(dirname "$iso")"
    echo "  ${YELLOW}${BOLD}Image:${NC}   $(basename "$iso")"
    echo -e "  ${BLUE}${BOLD}Size:${NC}    $(getsize "$iso")\n"
}

function burn {
    local iso="$1"
    local device="$2"

    if ! show_dev_info "$device"; then
        exit 1
    fi

    show_warning
    show_status "$iso" "$device"

    if ! confirm; then
        exit 1
    fi

    ARGS+=(if="$iso")
    ARGS+=(of="$device")
    sudo dd "${ARGS[@]}"

    return 0
}

function format {
    local device="$1"

    read -p "New volume label: " -r label
    sudo mkfs.ext4 "$device" -L "${label:-}"
}

function erase_dev {
    local device="$1"
    declare -a args=(bs=1M status=progress)

    if ! confirm; then
        return 1
    fi

    args+=(if=/dev/zero)
    args+=(of="$device")
    sudo dd "${args[@]}"

    return 0
}

function wipe {
    local device="$1"

    if ! show_dev_info "$device"; then
        exit 1
    fi

    show_warning

    if ! erase_dev "$device"; then
        return 1
    fi

    format "$device"
    return 0
}

function main {
    local iso="$1"
    local device="$2"

    for dep in "${DEPS[@]}"; do
        if ! command -v "$dep" >/dev/null; then
            logerr "'$dep' not found"
        fi
    done

    [[ -z "$iso" ]] && {
        usage
        exit 1
    }

    case "$iso" in
    --format)
        wipe "$device"
        exit
        ;;
    *) ;;
    esac

    iso=$(realpath "$iso")

    if [[ ! -f "$iso" ]]; then
        logerr "file not found: '$iso'"
    fi

    burn "$iso" "$device"
}

main "$@"