home/bin/wallpapers_preview

   1 #! /bin/bash
   2
   3 ### XXX Chose not to 'set -e' because arithmetic evaluation can cause a non-zero exit.
   4 ### XXX Chose not to 'set -u' because unset params ($1, $2, ...) cause failures.
   5 ### Solutions to the above are ugly.
   6
   7 declare -a paths
   8 declare -i n=0
   9
  10 read_command() {
  11     local char
  12
  13     read -rsn 1 char
  14     case "$char" in
  15         q | Q) echo 'CMD_QUIT';;
  16         h | H) echo 'CMD_MOVE_BACK';;
  17         l | L) echo 'CMD_MOVE_FORWARD';;
  18         f | F) echo 'CMD_FAVORITE_ADD';;
  19         r | R) echo 'CMD_FAVORITE_REMOVE';;
  20         s | S) echo 'CMD_SET_CURRENT';;
  21             *) echo 'CMD_UKNOWN';;
  22     esac
  23 }
  24
  25 paths_set() {
  26     local path
  27
  28     while read -r path
  29     do
  30         if file "$path" | grep 'image data' > /dev/null
  31         then
  32             (( n++ ))
  33             # \r jumps to the beginning of the line:
  34             printf '\rFound %d images.' "$n" >&2
  35             paths["$(( n - 1 ))"]="$path"
  36         fi
  37     done
  38     printf '\n' >&2
  39 }
  40
  41 paths_set_from_dir_find() {
  42     paths_set < <(find "$1" -type f)
  43 }
  44
  45 paths_set_from_favs() {
  46     paths_set < <(sort -k 2 "$FILE_WALLPAPER_FAVS" | awk '{sub("^" $1 " +", ""); print}')
  47 }
  48
  49 set_wallpaper() {
  50     local -ri i="$1"
  51     local -r path="$2"
  52
  53     printf '%d of %d %s\n' "$(( i + 1 ))" "$n" "$path"
  54     feh --bg-scale "$path"
  55 }
  56
  57 paths_preview() {
  58     local -i i=0
  59     local path="${paths[$i]}"
  60
  61     set_wallpaper "$i" "$path"
  62
  63     while :
  64     do
  65         if [[ "${paths[$i]}" != "$path" ]]
  66         then
  67             path="${paths[$i]}"
  68             set_wallpaper "$i" "$path"
  69         fi
  70
  71         case "$(read_command)" in
  72             CMD_QUIT)
  73                 exit 0;;
  74             CMD_MOVE_BACK)
  75                 (( i = i == 0 ? (n - 1) : i - 1));;
  76             CMD_MOVE_FORWARD)
  77                 (( i = (i + 1) % n ));;
  78             CMD_FAVORITE_ADD)
  79                 printf 'Adding to favorites set: "%s"\n' "$path" >&2
  80                 wallpaper_fav;;
  81             CMD_FAVORITE_REMOVE)
  82                 printf 'Removing from favorites set: "%s"\n' "$path" >&2
  83                 digest=$(sha256sum "$path" | awk '{print $1}')
  84                 grep -v "$digest" "$FILE_WALLPAPER_FAVS" \
  85                 | sort -u \
  86                 | sponge "$FILE_WALLPAPER_FAVS"
  87                 ;;
  88             CMD_SET_CURRENT)
  89                 printf 'Setting as current: "%s"\n' "$path" >&2
  90                 echo "$path" > "$FILE_WALLPAPER_CURR";;
  91             CMD_UKNOWN)
  92                 continue;;
  93         esac
  94     done
  95 }
  96
  97 main() {
  98     case "$1" in
  99         f | fav) paths_set_from_favs;;
 100         d | dir) paths_set_from_dir_find "$2";;
 101         a | all) paths_set_from_dir_find "$DIR_WALLPAPERS";;
 102         '')
 103             paths_set_from_dir_find "$DIR_WALLPAPERS";;
 104         *)
 105             printf 'Error: unknown source "%s"\n' "$1" >&2
 106             exit 1;;
 107     esac
 108
 109     paths_preview
 110 }
 111
 112 main "$@"