lib.bash

color::get() {
  local color=$1

  case "$color" in
    off)           printf "\033[0m" ;;# Text Reset

    bold)          printf "\033[1m" ;; # just bold
    unbold)        printf "\033[22m" ;; # normal intensity (not bold)

    # Colors
    black)         printf "\033[0;30m" ;;# black
    red)           printf "\033[0;31m" ;;# red
    green)         printf "\033[0;32m" ;;# green
    yellow)        printf "\033[0;33m" ;;# yellow
    blue)          printf "\033[0;34m" ;;# blue
    purple)        printf "\033[0;35m" ;;# purple
    cyan)          printf "\033[0;36m" ;;# cyan
    white)         printf "\033[0;37m" ;;# white

    # bold
    bblack)        printf "\033[1;30m" ;;# black
    bred)          printf "\033[1;31m" ;;# red
    bgreen)        printf "\033[1;32m" ;;# green
    byellow)       printf "\033[1;33m" ;;# yellow
    bblue)         printf "\033[1;34m" ;;# blue
    bpurple)       printf "\033[1;35m" ;;# purple
    bcyan)         printf "\033[1;36m" ;;# cyan
    bwhite)        printf "\033[1;37m" ;;# white

    # underline
    ublack)        printf "\033[4;30m" ;;# black
    ured)          printf "\033[4;31m" ;;# red
    ugreen)        printf "\033[4;32m" ;;# green
    uyellow)       printf "\033[4;33m" ;;# yellow
    ublue)         printf "\033[4;34m" ;;# blue
    upurple)       printf "\033[4;35m" ;;# purple
    ucyan)         printf "\033[4;36m" ;;# cyan
    uwhite)        printf "\033[4;37m" ;;# white

    # background
    on_black)      printf "\033[40m" ;;# black
    on_red)        printf "\033[41m" ;;# red
    on_green)      printf "\033[42m" ;;# green
    on_yellow)     printf "\033[43m" ;;# yellow
    on_blue)       printf "\033[44m" ;;# blue
    on_purple)     printf "\033[45m" ;;# purple
    on_cyan)       printf "\033[46m" ;;# cyan
    on_white)      printf "\033[47m" ;;# white

    # intense
    iblack)        printf "\033[0;90m" ;;# black
    ired)          printf "\033[0;91m" ;;# red
    igreen)        printf "\033[0;92m" ;;# green
    iyellow)       printf "\033[0;93m" ;;# yellow
    iblue)         printf "\033[0;94m" ;;# blue
    ipurple)       printf "\033[0;95m" ;;# purple
    icyan)         printf "\033[0;96m" ;;# cyan
    iwhite)        printf "\033[0;97m" ;;# white

    # bold intense
    biblack)       printf "\033[1;90m" ;;# black
    bired)         printf "\033[1;91m" ;;# red
    bigreen)       printf "\033[1;92m" ;;# green
    biyellow)      printf "\033[1;93m" ;;# yellow
    biblue)        printf "\033[1;94m" ;;# blue
    bipurple)      printf "\033[1;95m" ;;# purple
    bicyan)        printf "\033[1;96m" ;;# cyan
    biwhite)       printf "\033[1;97m" ;;# white

    # intense bg
    on_iblack)     printf "\033[0;100m" ;;# black
    on_ired)       printf "\033[0;101m" ;;# red
    on_igreen)     printf "\033[0;102m" ;;# green
    on_iyellow)    printf "\033[0;103m" ;;# yellow
    on_iblue)      printf "\033[0;104m" ;;# blue
    on_ipurple)    printf "\033[10;95m" ;;# purple
    on_icyan)      printf "\033[0;106m" ;;# cyan
    on_iwhite)     printf "\033[0;107m" ;;# white
  esac
}

color::echo() {
  local color=$1; shift
  color=$(color::get "$color")

  printf "${color}%s$(color::off)\n" "$@"
}

color::off() {
  color::get "off"
}

color::bold() {
  color::get 'bold'
}

color::unbold() {
  color::get 'unbold'
}

header() {
  color::echo "ucyan" "$@"
}

header2() {
  color::echo "bcyan" "  $@"
}

fs_header() {
  local fs_name=$1
  local status_color=$2
  local status=$3

  printf "  $(color::get 'bwhite')%s [$(color::unbold)$(color::get "$status_color")%s$(color::get 'bwhite')]:$(color::off)\n" "$fs_name" "$status"
}

create_motd() {
  local dir=$1
  local outfile=$2

  cat "$dir"/* | grep -v '^# zfs_motd' > "$outfile"
}

storage_info() {
  local pools=$( get_all_zfs_pools )
  IFS=$'\t\n'
  header "Pools:"

  for fs in $pools; do
    draw_graph_bar_for "$fs"
  done \
    | column -t -s $'\t' \
    | indent

  echo ""

  header "Compression Ratios:"
  zfs get all \
    | grep -E '\bcompressratio' \
    | sed -E $'s@[[:space:]][[:space:]]+@\t@g' \
    | awk -F $'\t'  '{ print $1 "\t" $3 }' \
    | column -t -s $'\t' \
    | indent

  echo ""

  header "Status:"

  for fs in $pools; do
    local state=$( pool_state "$fs" )
    local state_color=$( pool_state_color "$state" )

    fs_header "$fs" "$state_color" "$state"
    scrub_info "$fs" \
      | indent \
      | indent

    echo ""
  done

  echo "# zfs_motd generated at: $( date )"
}

pool_state() {
  local pool=$1

  zpool status "$pool" \
    | grep "state:" \
    | awk -F ': ' '{ print $2 }'
}

pool_state_color() {
  local state=$1

  case "$state" in
    ONLINE) echo "green" ;;
    *) echo "red"
  esac
}

# ZFS in FreeBSD 13 has changed slightly; `zpool status` does not
# output a `scan` line unless a scrub has been requested.
scrub_info() {
  local pool=$1
  local info

  info=$( zpool status "$pool" \
    | grep -A 2 '^  scan: ' \
    | grep -E '(^        )|(scan: )' \
    | sed -E 's/^.{8}//' )

  if [[ -z "$info" ]]; then
    echo "none requested"
  else
    echo "$info"
  fi
}

get_all_zfs_pools() {
  zpool list -pH \
    | awk -F $'\t' '{ print $1 }'
}

get_free_space_fields() {
  local path=$1

  zpool list -pH "$path"
}

get_total_space_from() {
  local line=$1

  awk -F $'\t' '{ print $2 }' <<< "$line"
}

get_used_space_from() {
  local line=$1

  awk '{ print $3 }' <<< "$line"
}

get_percent_space_from() {
  local line=$1
  local size=$( awk '{ print $2 }' <<< "$line" )
  local used=$( awk '{ print $3 }' <<< "$line" )

  local percent=$(
    bc -l <<< "$used / $size * 100" \
      | awk -F '.' '{ print $1 }'
  )

  if [[ -z "$percent" ]]; then
    percent=0
  fi

  echo "$percent"
}

# convert from bytes to human readable size
hr_size() {
  local sizes=("B" "KB" "MB" "GB" "TB" "PB")
  local size=$1

  for i in $( seq 0 5 ); do
    if [[ "$( printf "%.0f" "$size" )" -lt 1024 ]]; then
      break
    fi

    size=$( bc -l <<< "$size / 1024" )
  done

  printf "%.1f%s" "$size" "${sizes[$i]}"
}

indent() {
  while read LINE; do
    echo "  $LINE"
  done
}

draw_graph_bar() {
  local title=$1
  local percent=$2
  local suffix=$3

  local width=40
  local blockcount=$( bc -l <<< "$width * ($percent / 100)" )
  blockcount=$( printf '%.0f' "$blockcount" )

  local bar_color=$( color::get green )

  if [[ "$percent" -gt 85 ]]; then
    bar_color=$( color::get red )
  elif [[ "$percent" -gt 65 ]]; then
    bar_color=$( color::get yellow )
  fi


  printf "%s\t[$( color::get green )" "$title"
  
  if [[ "$blockcount" -gt 0 ]]; then
    printf "\u2588%.0s" $( seq 1 $blockcount )
  fi

  printf "$( color::off )"
  printf " %.0s" $( seq 1 $(( width - blockcount )))
  printf "] %2s%% %s\n" "$percent" "$suffix"
}

draw_graph_bar_for() {
  local path=$1

  local fields=$( get_free_space_fields "$path" )
  local percent=$( get_percent_space_from "$fields" )
  local total=$( get_total_space_from "$fields" )
  local used=$( get_used_space_from "$fields" )

  total=$( hr_size "$total" )
  used=$( hr_size "$used" )

  draw_graph_bar "$path" "$percent" "${used}/${total}"
}