plugins/preview-tui

   1 #!/usr/bin/env bash
   2
   3 # Description: Terminal based file previewer
   4 #
   5 # Note: This plugin needs a "NNN_FIFO" to work. See man.
   6 #
   7 # Dependencies:
   8 #   - Supports 6 independent methods to preview with:
   9 #       - tmux (>=3.0), or
  10 #       - kitty with allow_remote_control and listen_on set in kitty.conf, or
  11 #       - wezterm (https://wezfurlong.org/wezterm), or
  12 #       - QuickLook on WSL (https://github.com/QL-Win/QuickLook), or
  13 #       - Windows Terminal (https://github.com/Microsoft/Terminal | https://aka.ms/terminal) with WSL, or
  14 #       - $NNN_TERMINAL set to a terminal (it's xterm by default).
  15 #   - less or $NNN_PAGER
  16 #   - tree or exa or (GNU) ls
  17 #   - mediainfo or file
  18 #   - mktemp
  19 #   - unzip
  20 #   - tar
  21 #   - man
  22 #   - optional: bsdtar or atool for additional archive preview
  23 #   - optional: bat for code syntax highlighting
  24 #   - optional: ueberzug, kitty terminal, wezterm terminal, viu, catimg or chafa for images
  25 #   - optional: convert(ImageMagick) for playing gif preview (required for kitty image previews)
  26 #   - optional: ffmpegthumbnailer for video thumbnails (https://github.com/dirkvdb/ffmpegthumbnailer)
  27 #   - optional: ffmpeg for audio thumbnails
  28 #   - optional: libreoffce for opendocument/officedocument preview
  29 #   - optional: pdftoppm(poppler) for pdf thumbnails
  30 #   - optional: gnome-epub-thumbnailer for epub thumbnails (https://gitlab.gnome.org/GNOME/gnome-epub-thumbnailer)
  31 #   - optional: fontpreview for font preview (https://github.com/sdushantha/fontpreview)
  32 #   - optional: djvulibre for djvu
  33 #   - optional: glow or lowdown for markdown
  34 #   - optional: w3m or lynx or elinks for html
  35 #   - optional: set/export NNN_ICONLOOKUP as 1 to enable file icons in front of directory previews with .iconlookup
  36 #       Icons and colors are configurable in .iconlookup
  37 #   - optional: scope.sh file viewer from ranger.
  38 #       1. drop scope.sh executable in $PATH
  39 #       2. set/export $NNN_SCOPE as 1
  40 #   - optional: pistol file viewer (https://github.com/doronbehar/pistol).
  41 #       1. install pistol
  42 #       2. set/export $NNN_PISTOL as 1
  43 #
  44 # Usage:
  45 #   You need to set a NNN_FIFO path and a key for the plugin with NNN_PLUG,
  46 #   then start `nnn`:
  47 #
  48 #     $ nnn -a
  49 #
  50 #   or
  51 #
  52 #     $ NNN_FIFO=/tmp/nnn.fifo nnn
  53 #
  54 #   Then launch the `preview-tui` plugin in `nnn`.
  55 #
  56 #   If you provide the same NNN_FIFO to all nnn instances, there will be a
  57 #   single common preview window. If you provide different FIFO path (e.g.
  58 #   with -a), they will be independent.
  59 #
  60 #   The previews will be shown in a tmux split. If that isn't possible, it
  61 #   will try to use a kitty terminal split. And as a final fallback, a
  62 #   different terminal window will be used ($NNN_TERMINAL).
  63 #
  64 #   Kitty users need something similar to the following in their kitty.conf:
  65 #   - `allow_remote_control yes`
  66 #   - `listen_on unix:$TMPDIR/kitty`
  67 #   - `enabled_layouts splits` (optional)
  68 #   With ImageMagick installed, this terminal can use the icat kitten to display images.
  69 #   Refer to kitty documentation for further details.
  70 #
  71 #   Wezterm should work out of the box. If `NNN_PREVIEWIMGPROG` is not specified it will use
  72 #   built in iTerm2 image protocol.
  73 #
  74 #   Note that GNU ls is used for its `--group-directories-first` flag.
  75 #   On MacOS this may be installed with `brew install coreutils`, or the flag can be removed.
  76 #   iTerm2 users are recommended to use viu to view images without getting pixelated.
  77 #
  78 #   Windows Terminal users can set "Profile termination behavior" under "Profile > Advanced" settings
  79 #   to automatically close pane on quit when exit code is 0.
  80 #
  81 # Shell: Bash (for environment manipulation through arrays)
  82 # Authors: Todd Yamakawa, Léo Villeveygoux, @Recidiviste, Mario Ortiz Manero, Luuk van Baal, @WanderLanz
  83
  84 NNN_SPLIT=${NNN_SPLIT:-}           # Set permanent split direction
  85 NNN_TERMINAL=${NNN_TERMINAL:-}     # Set external terminal to be used
  86 NNN_SPLITSIZE=${NNN_SPLITSIZE:-50} # Set previewer split size percentage
  87 TMPDIR=${TMPDIR:-/tmp}
  88 NNN_PARENT=${NNN_FIFO#*.}
  89 [ "$NNN_PARENT" -eq "$NNN_PARENT" ] 2>/dev/null || NNN_PARENT="" # Make empty if non-numeric
  90 ENVVARS=(
  91   "PWD=$PWD"
  92   "PATH=$PATH"
  93   "NNN_FIFO=$NNN_FIFO"
  94   "NNN_SCOPE=${NNN_SCOPE:-0}"
  95   "NNN_PISTOL=${NNN_PISTOL:-0}"
  96   "NNN_ICONLOOKUP=${NNN_ICONLOOKUP:-0}"
  97   "NNN_PAGER=${NNN_PAGER:-less -P?n -R}"
  98   "NNN_BATTHEME=${NNN_BATTHEME:-ansi}"
  99   "NNN_BATSTYLE=${NNN_BATSTYLE:-numbers}"
 100   "NNN_PREVIEWWIDTH=${NNN_PREVIEWWIDTH:-1920}"
 101   "NNN_PREVIEWHEIGHT=${NNN_PREVIEWHEIGHT:-1080}"
 102   "NNN_PREVIEWDIR=${NNN_PREVIEWDIR:-$TMPDIR/nnn/previews}"
 103   "NNN_PREVIEWIMGPROG=${NNN_PREVIEWIMGPROG:-}"
 104   "FIFOPID=$TMPDIR/nnn-preview-tui-fifopid.$NNN_PARENT"
 105   "FIFOPATH=$TMPDIR/nnn-preview-tui-fifo.$NNN_PARENT"
 106   "PREVIEWPID=$TMPDIR/nnn-preview-tui-previewpid.$NNN_PARENT"
 107   "CURSEL=$TMPDIR/nnn-preview-tui-selection.$NNN_PARENT"
 108   "FIFO_UEBERZUG=$TMPDIR/nnn-preview-tui-ueberzug-fifo.$NNN_PARENT"
 109   "POSOFFSET=$TMPDIR/nnn-preview-tui-posoffset"
 110 )
 111
 112 trap '' PIPE
 113 exists() { type "$1" >/dev/null 2>&1 ;}
 114 pkill() { command pkill "$@" >/dev/null 2>&1 ;}
 115 prompt() { clear; printf "%b" "$@"; cfg=$(stty -g); stty raw -echo; head -c 1; stty "$cfg" ;}
 116 pidkill() {
 117     if [ -f "$1" ]; then
 118         PID="$(cat "$1" 2>/dev/null)" || return 1
 119         kill "$PID" >/dev/null 2>&1
 120         RET=$?
 121         wait "$PID" 2>/dev/null
 122         return $RET
 123     fi
 124     return 1
 125 }
 126
 127 start_preview() {
 128     if [ -e "${TMUX%%,*}" ] && tmux -V | grep -q '[ -][3456789]\.'; then
 129         NNN_TERMINAL=tmux
 130     elif [ -n "$KITTY_LISTEN_ON" ]; then
 131         NNN_TERMINAL=kitty
 132     elif [ -n "$WEZTERM_PANE" ]; then
 133         NNN_TERMINAL=wezterm
 134     elif [ -z "$NNN_TERMINAL" ] && [ "$TERM_PROGRAM" = "iTerm.app" ]; then
 135         NNN_TERMINAL=iterm
 136     elif [ -n "$WT_SESSION" ]; then
 137         NNN_TERMINAL=winterm
 138     else
 139         NNN_TERMINAL="${NNN_TERMINAL:-xterm}"
 140     fi
 141
 142     if [ -z "$NNN_SPLIT" ] && [ $(($(tput lines) * 2)) -gt "$(tput cols)" ]; then
 143         NNN_SPLIT='h'
 144     elif [ "$NNN_SPLIT" != 'h' ]; then
 145         NNN_SPLIT='v'
 146     fi
 147
 148     ENVVARS+=("NNN_TERMINAL=$NNN_TERMINAL" "NNN_SPLIT=$NNN_SPLIT" "QLPATH=$2" "PREVIEW_MODE=1")
 149     case "$NNN_TERMINAL" in
 150         iterm|winterm) # need run in separate shell command: escape
 151             ENVVARS=("${ENVVARS[@]/#/\\\"}")
 152             ENVVARS=("${ENVVARS[@]/%/\\\"}")
 153             command="$SHELL -c 'env ${ENVVARS[*]} \\\"$0\\\" \\\"$1\\\"'" ;;
 154     esac
 155
 156     case "$NNN_TERMINAL" in
 157         tmux) # tmux splits are inverted
 158             ENVVARS=("${ENVVARS[@]/#/-e}")
 159             if [ "$NNN_SPLIT" = "v" ]; then split="h"; else split="v"; fi
 160             tmux split-window "${ENVVARS[@]}" -d"$split" -p"$NNN_SPLITSIZE" "$0" "$1" ;;
 161         kitty) # Setting the layout for the new window. It will be restored after the script ends.
 162             ENVVARS=("${ENVVARS[@]/#/--env=}")
 163             kitty @ goto-layout splits
 164             # Trying to use kitty's integrated window management as the split window.
 165             kitty @ launch --no-response --title "preview-tui" --keep-focus \
 166                 --cwd "$PWD" "${ENVVARS[@]}" --location "${NNN_SPLIT}split" "$0" "$1" ;;
 167         wezterm)
 168             export "${ENVVARS[@]}"
 169             if [ "$NNN_SPLIT" = "v" ]; then split="--horizontal"; else split="--bottom"; fi
 170             wezterm cli split-pane --cwd "$PWD" $split --percent "$NNN_SPLITSIZE" "$0" "$1" >/dev/null
 171             wezterm cli activate-pane-direction Prev ;;
 172         iterm)
 173             if [ "$NNN_SPLIT" = "h" ]; then split="horizontally"; else split="vertically"; fi
 174             osascript <<-EOF
 175             tell application "iTerm"
 176                 tell current session of current window
 177                     split $split with default profile command "$command"
 178                 end tell
 179             end tell
 180 EOF
 181             ;;
 182         winterm)
 183             if [ "$NNN_SPLIT" = "h" ]; then split="H"; else split="V"; fi
 184             wt -w 0 sp -$split -s"0.$NNN_SPLITSIZE" "$command" \; -w 0 mf previous 2>/dev/null ;;
 185         *)  if [ -n "$2" ]; then
 186                 env "${ENVVARS[@]}" QUICKLOOK=1 "$0" "$1" &
 187             else
 188                 env "${ENVVARS[@]}" "$NNN_TERMINAL" -e "$0" "$1" &
 189             fi ;;
 190     esac
 191 }
 192
 193 toggle_preview() {
 194     export "${ENVVARS[@]}"
 195     if exists QuickLook.exe; then
 196         QLPATH="QuickLook.exe"
 197     elif exists Bridge.exe; then
 198         QLPATH="Bridge.exe"
 199     fi
 200     if pidkill "$FIFOPID"; then
 201         [ -p "$NNN_PPIPE" ] && printf "0" > "$NNN_PPIPE"
 202         pidkill "$PREVIEWPID"
 203         pkill -f "tail --follow $FIFO_UEBERZUG"
 204         if [ -n "$QLPATH" ] && stat "$1"; then
 205             f="$(wslpath -w "$1")" && "$QLPATH" "$f" &
 206         fi
 207     else
 208         [ -p "$NNN_PPIPE" ] && printf "1" > "$NNN_PPIPE"
 209         start_preview "$1" "$QLPATH"
 210     fi
 211 }
 212
 213 fifo_pager() {
 214     cmd="$1"
 215     shift
 216
 217     # We use a FIFO to access $NNN_PAGER PID in jobs control
 218     mkfifo "$FIFOPATH" || return
 219
 220     $NNN_PAGER < "$FIFOPATH" &
 221     printf "%s" "$!" > "$PREVIEWPID"
 222
 223     (
 224         exec > "$FIFOPATH"
 225         if [ "$cmd" = "pager" ]; then
 226             if exists bat; then
 227                 bat --terminal-width="$cols" --decorations=always --color=always \
 228                     --paging=never --style="$NNN_BATSTYLE" --theme="$NNN_BATTHEME" "$@" &
 229             else
 230                 $NNN_PAGER "$@" &
 231             fi
 232         else
 233             "$cmd" "$@" &
 234         fi
 235     )
 236
 237     rm "$FIFOPATH"
 238 }
 239
 240 # Binary file: show file info inside the pager
 241 print_bin_info() {
 242     printf -- "-------- \033[1;31mBinary file\033[0m --------\n"
 243     if exists mediainfo; then
 244         mediainfo "$1"
 245     else
 246         file -b "$1"
 247     fi
 248 }
 249
 250 handle_mime() {
 251     case "$2" in
 252         image/jpeg) image_preview "$cols" "$lines" "$1" ;;
 253         image/gif) generate_preview "$cols" "$lines" "$1" "gif" ;;
 254         image/vnd.djvu) generate_preview "$cols" "$lines" "$1" "djvu" ;;
 255         image/*) generate_preview "$cols" "$lines" "$1" "image" ;;
 256         video/*) generate_preview "$cols" "$lines" "$1" "video" ;;
 257         audio/*) generate_preview "$cols" "$lines" "$1" "audio" ;;
 258         application/font*|application/*opentype|font/*) generate_preview "$cols" "$lines" "$1" "font" ;;
 259         */*office*|*/*document*|*/*msword|*/*ms-excel) generate_preview "$cols" "$lines" "$1" "office" ;;
 260         application/zip) fifo_pager unzip -l "$1" ;;
 261         text/troff)
 262             if exists man; then
 263                 fifo_pager man -Pcat -l "$1"
 264             else
 265                 fifo_pager pager "$1"
 266             fi ;;
 267         *) handle_ext "$1" "$3" "$4" ;;
 268     esac
 269 }
 270
 271 handle_ext() {
 272     case "$2" in
 273         epub) generate_preview "$cols" "$lines" "$1" "epub" ;;
 274         pdf) generate_preview "$cols" "$lines" "$1" "pdf" ;;
 275         gz|bz2) fifo_pager tar -tvf "$1" ;;
 276         md) if exists glow; then
 277                 fifo_pager glow -s dark "$1"
 278             elif exists lowdown; then
 279                 fifo_pager lowdown -Tterm "$1"
 280             else
 281                 fifo_pager pager "$1"
 282             fi ;;
 283         htm|html|xhtml)
 284             if exists w3m; then
 285                 fifo_pager w3m "$1"
 286             elif exists lynx; then
 287                 fifo_pager lynx "$1"
 288             elif exists elinks; then
 289                 fifo_pager elinks "$1"
 290             else
 291                 fifo_pager pager "$1"
 292             fi ;;
 293         7z|a|ace|alz|arc|arj|bz|cab|cpio|deb|jar|lha|lz|lzh|lzma|lzo\
 294         |rar|rpm|rz|t7z|tar|tbz|tbz2|tgz|tlz|txz|tZ|tzo|war|xpi|xz|Z)
 295             if exists atool; then
 296                 fifo_pager atool -l "$1"
 297             elif exists bsdtar; then
 298                 fifo_pager bsdtar -tvf "$1"
 299             fi ;;
 300         *) if [ "$3" = "bin" ]; then
 301                fifo_pager print_bin_info "$1"
 302            else
 303                fifo_pager pager "$1"
 304            fi ;;
 305     esac
 306 }
 307
 308 preview_file() {
 309     clear
 310     # Trying to use pistol if it's available.
 311     if [ "$NNN_PISTOL" -ne 0 ] && exists pistol; then
 312         fifo_pager pistol "$1"
 313         return
 314     fi
 315
 316     # Trying to use scope.sh if it's available.
 317     if [ "$NNN_SCOPE" -ne 0 ] && exists scope.sh; then
 318         fifo_pager scope.sh "$1" "$cols" "$lines" "$(mktemp -d)" "True"
 319         return
 320     fi
 321
 322     # Use QuickLook if it's available.
 323     if [ -n "$QUICKLOOK" ]; then
 324         stat "$1" && f="$(wslpath -w "$1")" && "$QLPATH" "$f" &
 325         return
 326     fi
 327
 328     # Detecting the exact type of the file: the encoding, mime type, and extension in lowercase.
 329     encoding="$(file -bL --mime-encoding -- "$1")"
 330     mimetype="$(file -bL --mime-type -- "$1")"
 331     ext="${1##*.}"
 332     [ -n "$ext" ] && ext="$(printf "%s" "${ext}" | tr '[:upper:]' '[:lower:]')"
 333     lines=$(tput lines)
 334     cols=$(tput cols)
 335
 336     # Otherwise, falling back to the defaults.
 337     if [ -d "$1" ]; then
 338         cd "$1" || return
 339         if [ "$NNN_ICONLOOKUP" -ne 0 ] && [ -f "$(dirname "$0")"/.iconlookup ]; then
 340             [ "$NNN_SPLIT" = v ] && BSTR="\n"
 341             # shellcheck disable=SC2012
 342             ls -F --group-directories-first | head -n "$((lines - 3))" | "$(dirname "$0")"/.iconlookup -l "$cols" -B "$BSTR" -b " "
 343         elif exists tree; then
 344             fifo_pager tree --filelimit "$(find . -maxdepth 1 | wc -l)" -L 3 -C -F --dirsfirst --noreport
 345         elif exists exa; then
 346             exa -G --group-directories-first --colour=always
 347         else
 348             fifo_pager ls -F --group-directories-first --color=always
 349         fi
 350         cd ..
 351     elif [ "${encoding#*)}" = "binary" ]; then
 352         handle_mime "$1" "$mimetype" "$ext" "bin"
 353     else
 354         handle_mime "$1" "$mimetype" "$ext"
 355     fi
 356 }
 357
 358 generate_preview() {
 359   if [ -n "$QLPATH" ] && stat "$3"; then
 360         f="$(wslpath -w "$3")" && "$QLPATH" "$f" &
 361   elif [ ! -f "$NNN_PREVIEWDIR/$3.jpg" ] || [ -n "$(find -L "$3" -newer "$NNN_PREVIEWDIR/$3.jpg")" ]; then
 362         mkdir -p "$NNN_PREVIEWDIR/${3%/*}"
 363         case $4 in
 364             audio) ffmpeg -i "$3" -filter_complex "scale=iw*min(1\,min($NNN_PREVIEWWIDTH/iw\,ih)):-1" "$NNN_PREVIEWDIR/$3.jpg" -y ;;
 365             epub) gnome-epub-thumbnailer "$3" "$NNN_PREVIEWDIR/$3.jpg" ;;
 366             font) fontpreview -i "$3" -o "$NNN_PREVIEWDIR/$3.jpg" ;;
 367             gif) if [ -p "$FIFO_UEBERZUG" ] && exists convert; then
 368                     frameprefix="$NNN_PREVIEWDIR/$3/${3##*/}"
 369                     if [ ! -d "$NNN_PREVIEWDIR/$3" ]; then
 370                         mkdir -p "$NNN_PREVIEWDIR/$3"
 371                         convert -coalesce -resize "$NNN_PREVIEWWIDTH"x"$NNN_PREVIEWHEIGHT"\> "$3" "$frameprefix.jpg" ||
 372                         MAGICK_TMPDIR="/tmp" convert -coalesce -resize "$NNN_PREVIEWWIDTH"x"$NNN_PREVIEWHEIGHT"\> "$3" "$frameprefix.jpg"
 373                     fi
 374                     frames=$(($(find "$NNN_PREVIEWDIR/$3" | wc -l) - 2))
 375                     [ $frames -lt 0 ] && return
 376                     while true; do
 377                         for i in $(seq 0 $frames); do
 378                             image_preview "$1" "$2" "$frameprefix-$i.jpg"
 379                             sleep 0.1
 380                         done
 381                     done &
 382                     printf "%s" "$!" > "$PREVIEWPID"
 383                     return
 384                  else
 385                     image_preview "$1" "$2" "$3"
 386                     return
 387                  fi ;;
 388             image) if exists convert; then
 389                        convert "$3" -flatten -resize "$NNN_PREVIEWWIDTH"x"$NNN_PREVIEWHEIGHT"\> "$NNN_PREVIEWDIR/$3.jpg"
 390                    else
 391                        image_preview "$1" "$2" "$3" && return
 392                    fi ;;
 393             office) libreoffice --convert-to jpg "$3" --outdir "$NNN_PREVIEWDIR/${3%/*}"
 394                     filename="$(printf "%s" "${3##*/}" | cut -d. -f1)"
 395                     mv "$NNN_PREVIEWDIR/${3%/*}/$filename.jpg" "$NNN_PREVIEWDIR/$3.jpg" ;;
 396             pdf) pdftoppm -jpeg -f 1 -singlefile "$3" "$NNN_PREVIEWDIR/$3" ;;
 397             djvu) ddjvu -format=ppm -page=1 "$3" "$NNN_PREVIEWDIR/$3.jpg" ;;
 398             video) ffmpegthumbnailer -m -s0 -i "$3" -o "$NNN_PREVIEWDIR/$3.jpg" || rm "$NNN_PREVIEWDIR/$3.jpg" ;;
 399         esac
 400     fi
 401     if [ -f "$NNN_PREVIEWDIR/$3.jpg" ]; then
 402         image_preview "$1" "$2" "$NNN_PREVIEWDIR/$3.jpg"
 403     else
 404         fifo_pager print_bin_info "$3"
 405     fi
 406 } >/dev/null 2>&1
 407
 408 image_preview() {
 409     clear
 410     exec >/dev/tty
 411     if [ "$NNN_TERMINAL" = "kitty" ] && [ -z "$NNN_PREVIEWIMGPROG" ]; then
 412         kitty +kitten icat --silent --scale-up --place "$1"x"$2"@0x0 --transfer-mode=stream --stdin=no "$3" &
 413     elif [ "$NNN_TERMINAL" = "wezterm" ] && [ -z "$NNN_PREVIEWIMGPROG" ]; then
 414         wezterm imgcat "$3" &
 415     elif exists ueberzug && { [ -z "$NNN_PREVIEWIMGPROG" ] || [ "$NNN_PREVIEWIMGPROG" = "ueberzug" ] ;}; then
 416         ueberzug_layer "$1" "$2" "$3" && return
 417     elif exists catimg   && { [ -z "$NNN_PREVIEWIMGPROG" ] || [ "$NNN_PREVIEWIMGPROG" = "catimg" ] ;}; then
 418         catimg "$3" &
 419     elif exists viu      && { [ -z "$NNN_PREVIEWIMGPROG" ] || [ "$NNN_PREVIEWIMGPROG" = "viu" ] ;}; then
 420         viu -t "$3" &
 421     elif exists chafa    && { [ -z "$NNN_PREVIEWIMGPROG" ] || [ "$NNN_PREVIEWIMGPROG" = "chafa" ] ;}; then
 422         chafa "$3" &
 423     else
 424         fifo_pager print_bin_info "$3" && return
 425     fi
 426     printf "%s" "$!" > "$PREVIEWPID"
 427 }
 428
 429 ueberzug_layer() {
 430     [ -f "$POSOFFSET" ] && read -r x y < "$POSOFFSET"
 431     printf '{"action": "add", "identifier": "nnn_ueberzug", "x": %d, "y": %d, "width": "%d", "height": "%d", "scaler": "fit_contain", "path": "%s"}\n'\
 432         "${x:-0}" "${y:-0}" "$1" "$2" "$3" > "$FIFO_UEBERZUG"
 433 }
 434
 435 ueberzug_remove() {
 436     printf '{"action": "remove", "identifier": "nnn_ueberzug"}\n' > "$FIFO_UEBERZUG"
 437 }
 438
 439 winch_handler() {
 440     clear
 441     pidkill "$PREVIEWPID"
 442     if [ -p "$FIFO_UEBERZUG" ]; then
 443         pkill -f "tail --follow $FIFO_UEBERZUG"
 444         tail --follow "$FIFO_UEBERZUG" | ueberzug layer --silent --parser json &
 445     fi
 446     preview_file "$(cat "$CURSEL")"
 447 }
 448
 449 preview_fifo() {
 450     while read -r selection; do
 451         if [ -n "$selection" ]; then
 452             pidkill "$PREVIEWPID"
 453             [ -p "$FIFO_UEBERZUG" ] && ueberzug_remove
 454             [ "$selection" = "close" ] && break
 455             preview_file "$selection"
 456             printf "%s" "$selection" > "$CURSEL"
 457         fi
 458     done < "$NNN_FIFO"
 459     sleep 0.1 # make sure potential preview by winch_handler is killed
 460     pkill -P "$$"
 461 }
 462
 463 if [ "$PREVIEW_MODE" -eq 1 ] 2>/dev/null; then
 464     if [ "$NNN_TERMINAL" != "kitty" ] && exists ueberzug; then
 465         mkfifo "$FIFO_UEBERZUG"
 466         tail --follow "$FIFO_UEBERZUG" | ueberzug layer --silent --parser json &
 467     fi
 468
 469     preview_file "$PWD/$1"
 470     preview_fifo &
 471     printf "%s" "$!" > "$FIFOPID"
 472     printf "%s" "$PWD/$1" > "$CURSEL"
 473     trap 'winch_handler; wait' WINCH
 474     trap 'rm "$PREVIEWPID" "$CURSEL" "$FIFO_UEBERZUG" "$FIFOPID" "$POSOFFSET" 2>/dev/null' INT HUP EXIT
 475     wait "$!" 2>/dev/null
 476     exit 0
 477 else
 478     if [ ! -r "$NNN_FIFO" ]; then
 479         prompt "No FIFO available! (\$NNN_FIFO='$NNN_FIFO')\nPlease read Usage in '$0'."
 480     elif [ "$KITTY_WINDOW_ID" ] && [ -z "$TMUX" ] && [ -z "$KITTY_LISTEN_ON" ]; then
 481         prompt "\$KITTY_LISTEN_ON not set!\nPlease read Usage in '$0'."
 482     else
 483         toggle_preview "$1" &
 484     fi
 485 fi