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/eza 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 #   - optional: sixel
  44 #       - terminal with sixel support. ex. foot, wezterm, iterm2, macterm, mintty, etc. (check https://www.arewesixelyet.com/)
  45 #       - tmux with sixel support (should be compiled with `./configure --enable-sixel`)
  46 #       dependencies: mpv, img2sixel
  47 #
  48 #
  49 # Usage:
  50 #   You need to set a NNN_FIFO path and a key for the plugin with NNN_PLUG,
  51 #   then start `nnn`:
  52 #
  53 #     $ nnn -a
  54 #
  55 #   or
  56 #
  57 #     $ NNN_FIFO=/tmp/nnn.fifo nnn
  58 #
  59 #   Then launch the `preview-tui` plugin in `nnn`.
  60 #
  61 #   If you provide the same NNN_FIFO to all nnn instances, there will be a
  62 #   single common preview window. If you provide different FIFO path (e.g.
  63 #   with -a), they will be independent.
  64 #
  65 #   The previews will be shown in a tmux split. If that isn't possible, it
  66 #   will try to use a kitty terminal split. And as a final fallback, a
  67 #   different terminal window will be used ($NNN_TERMINAL).
  68 #
  69 #   Kitty users need something similar to the following in their kitty.conf:
  70 #   - `allow_remote_control yes`
  71 #   - `listen_on unix:$TMPDIR/kitty`
  72 #   - `enabled_layouts splits` (optional)
  73 #   With ImageMagick installed, this terminal can use the icat kitten to display images.
  74 #   Refer to kitty documentation for further details.
  75 #
  76 #   Wezterm should work out of the box. If `NNN_PREVIEWIMGPROG` is not specified it will use
  77 #   built in iTerm2 image protocol.
  78 #
  79 #   Note that GNU ls is used for its `--group-directories-first` flag.
  80 #   On MacOS this may be installed with `brew install coreutils`, or the flag can be removed.
  81 #   iTerm2 users are recommended to use viu to view images without getting pixelated.
  82 #
  83 #   Windows Terminal users can set "Profile termination behavior" under "Profile > Advanced" settings
  84 #   to automatically close pane on quit when exit code is 0.
  85 #
  86 #   When specifying a different terminal, additional arguments are supported. In particular, you can
  87 #   append a specific title to the terminal and set it to "nofocus" in your WM config.
  88 #   E.g for alacritty and i3, you can set $NNN_TERMINAL to 'alacritty --title preview-tui' and add
  89 #   'no_focus [title="preview-tui"]' to your i3 config file.
  90 #
  91 # Shell: Bash (for environment manipulation through arrays)
  92 # Authors: Todd Yamakawa, Léo Villeveygoux, @Recidiviste, Mario Ortiz Manero, Luuk van Baal, @WanderLanz
  93
  94 NNN_SPLIT=${NNN_SPLIT:-}           # Set permanent split direction
  95 NNN_TERMINAL=${NNN_TERMINAL:-}     # Set external terminal to be used
  96 NNN_SPLITSIZE=${NNN_SPLITSIZE:-50} # Set previewer split size percentage
  97 TMPDIR=${TMPDIR:-/tmp}
  98 NNN_PARENT=${NNN_FIFO#*.}
  99 [ "$NNN_PARENT" -eq "$NNN_PARENT" ] 2>/dev/null || NNN_PARENT="" # Make empty if non-numeric
 100 ENVVARS=(
 101   "PWD=$PWD"
 102   "PATH=$PATH"
 103   "NNN_FIFO=$NNN_FIFO"
 104   "NNN_SCOPE=${NNN_SCOPE:-0}"
 105   "NNN_PISTOL=${NNN_PISTOL:-0}"
 106   "NNN_ICONLOOKUP=${NNN_ICONLOOKUP:-0}"
 107   "NNN_PAGER=${NNN_PAGER:-less -P?n -R -C}"
 108   "NNN_BATTHEME=${NNN_BATTHEME:-ansi}"
 109   "NNN_BATSTYLE=${NNN_BATSTYLE:-numbers}"
 110   "NNN_PREVIEWWIDTH=${NNN_PREVIEWWIDTH:-1920}"
 111   "NNN_PREVIEWHEIGHT=${NNN_PREVIEWHEIGHT:-1080}"
 112   "NNN_PREVIEWDIR=${NNN_PREVIEWDIR:-$TMPDIR/nnn/previews}"
 113   "NNN_PREVIEWIMGPROG=${NNN_PREVIEWIMGPROG:-}"
 114   "FIFOPID=$TMPDIR/nnn-preview-tui-fifopid.$NNN_PARENT"
 115   "FIFOPATH=$TMPDIR/nnn-preview-tui-fifo.$NNN_PARENT"
 116   "PREVIEWPID=$TMPDIR/nnn-preview-tui-previewpid.$NNN_PARENT"
 117   "CURSEL=$TMPDIR/nnn-preview-tui-selection.$NNN_PARENT"
 118   "FIFO_UEBERZUG=$TMPDIR/nnn-preview-tui-ueberzug-fifo.$NNN_PARENT"
 119   "POSOFFSET=$TMPDIR/nnn-preview-tui-posoffset"
 120 )
 121
 122 trap '' PIPE
 123 exists() { type "$1" >/dev/null 2>&1 ;}
 124 pkill() { command pkill "$@" >/dev/null 2>&1 ;}
 125 prompt() { clear; printf "%b" "$@"; cfg=$(stty -g); stty raw -echo; head -c 1; stty "$cfg" ;}
 126 pidkill() {
 127     if [ -f "$1" ]; then
 128         PID="$(cat "$1" 2>/dev/null)" || return 1
 129         kill "$PID" >/dev/null 2>&1
 130         RET=$?
 131         wait "$PID" 2>/dev/null
 132         return $RET
 133     fi
 134     return 1
 135 }
 136
 137 start_preview() {
 138     if [ -e "${TMUX%%,*}" ] && tmux -V | grep -q '[ -][3456789]\.'; then
 139         NNN_TERMINAL=tmux
 140     elif [ -n "$KITTY_LISTEN_ON" ]; then
 141         NNN_TERMINAL=kitty
 142     elif [ -n "$WEZTERM_PANE" ]; then
 143         NNN_TERMINAL=wezterm
 144     elif [ -z "$NNN_TERMINAL" ] && [ "$TERM_PROGRAM" = "iTerm.app" ]; then
 145         NNN_TERMINAL=iterm
 146     elif [ -n "$WT_SESSION" ]; then
 147         NNN_TERMINAL=winterm
 148     else
 149         NNN_TERMINAL="${NNN_TERMINAL:-xterm}"
 150     fi
 151
 152     if [ -z "$NNN_SPLIT" ] && [ $(($(tput lines) * 2)) -gt "$(tput cols)" ]; then
 153         NNN_SPLIT='h'
 154     elif [ "$NNN_SPLIT" != 'h' ]; then
 155         NNN_SPLIT='v'
 156     fi
 157
 158     ENVVARS+=("NNN_TERMINAL=$NNN_TERMINAL" "NNN_SPLIT=$NNN_SPLIT" "QLPATH=$2" "PREVIEW_MODE=1")
 159     case "$NNN_TERMINAL" in
 160         iterm|winterm) # need run in separate shell command: escape
 161             ENVVARS=("${ENVVARS[@]/#/\\\"}")
 162             ENVVARS=("${ENVVARS[@]/%/\\\"}")
 163             command="$SHELL -c 'env ${ENVVARS[*]} \\\"$0\\\" \\\"$1\\\"'" ;;
 164     esac
 165
 166     case "$NNN_TERMINAL" in
 167         tmux) # tmux splits are inverted
 168             ENVVARS=("${ENVVARS[@]/#/-e}")
 169             if [ "$NNN_SPLIT" = "v" ]; then split="h"; else split="v"; fi
 170             tmux split-window -l"$NNN_SPLITSIZE"% "${ENVVARS[@]}" -d"$split" -p"$NNN_SPLITSIZE" "$0" "$1" ;;
 171         kitty) # Setting the layout for the new window. It will be restored after the script ends.
 172             ENVVARS=("${ENVVARS[@]/#/--env=}")
 173             kitty @ goto-layout splits
 174             # Trying to use kitty's integrated window management as the split window.
 175             kitty @ launch --no-response --title "preview-tui" --keep-focus \
 176                 --cwd "$PWD" "${ENVVARS[@]}" --location "${NNN_SPLIT}split" "$0" "$1" ;;
 177         wezterm)
 178             export "${ENVVARS[@]}"
 179             if [ "$NNN_SPLIT" = "v" ]; then split="--horizontal"; else split="--bottom"; fi
 180             wezterm cli split-pane --cwd "$PWD" $split --percent "$NNN_SPLITSIZE" "$0" "$1" >/dev/null
 181             wezterm cli activate-pane-direction Prev ;;
 182         iterm)
 183             if [ "$NNN_SPLIT" = "h" ]; then split="horizontally"; else split="vertically"; fi
 184             osascript <<-EOF
 185             tell application "iTerm"
 186                 tell current session of current window
 187                     split $split with default profile command "$command"
 188                 end tell
 189             end tell
 190 EOF
 191             ;;
 192         winterm)
 193             if [ "$NNN_SPLIT" = "h" ]; then split="H"; else split="V"; fi
 194             wt -w 0 sp -$split -s"0.$NNN_SPLITSIZE" "$command" \; -w 0 mf previous 2>/dev/null ;;
 195         *)  if [ -n "$2" ]; then
 196                 env "${ENVVARS[@]}" QUICKLOOK=1 "$0" "$1" &
 197             else
 198                 # shellcheck disable=SC2086 # (allow arguments)
 199                 env "${ENVVARS[@]}" $NNN_TERMINAL -e "$0" "$1" &
 200             fi ;;
 201     esac
 202 }
 203
 204 toggle_preview() {
 205     export "${ENVVARS[@]}"
 206     if exists QuickLook.exe; then
 207         QLPATH="QuickLook.exe"
 208     elif exists Bridge.exe; then
 209         QLPATH="Bridge.exe"
 210     fi
 211     if pidkill "$FIFOPID"; then
 212         [ -p "$NNN_PPIPE" ] && printf "0" > "$NNN_PPIPE"
 213         pidkill "$PREVIEWPID"
 214         pkill -f "tail --follow $FIFO_UEBERZUG"
 215         if [ -n "$QLPATH" ] && stat "$1"; then
 216             f="$(wslpath -w "$1")" && "$QLPATH" "$f" &
 217         fi
 218     else
 219         [ -p "$NNN_PPIPE" ] && printf "1" > "$NNN_PPIPE"
 220         start_preview "$1" "$QLPATH"
 221     fi
 222 }
 223
 224 fifo_pager() {
 225     cmd="$1"
 226     shift
 227
 228     # We use a FIFO to access $NNN_PAGER PID in jobs control
 229     mkfifo "$FIFOPATH" || return
 230
 231     $NNN_PAGER < "$FIFOPATH" &
 232     printf "%s" "$!" > "$PREVIEWPID"
 233
 234     (
 235         exec > "$FIFOPATH"
 236         if [ "$cmd" = "pager" ]; then
 237             if exists bat; then
 238                 bat --terminal-width="$cols" --decorations=always --color=always \
 239                     --paging=never --style="$NNN_BATSTYLE" --theme="$NNN_BATTHEME" "$@" &
 240             else
 241                 $NNN_PAGER "$@" &
 242             fi
 243         else
 244             "$cmd" "$@" &
 245         fi
 246     )
 247
 248     rm "$FIFOPATH"
 249 }
 250
 251 # Binary file: show file info inside the pager
 252 print_bin_info() {
 253     printf -- "-------- \033[1;31mBinary file\033[0m --------\n"
 254     if exists mediainfo; then
 255         mediainfo "$1"
 256     else
 257         file -b "$1"
 258     fi
 259 }
 260
 261 handle_mime() {
 262     case "$2" in
 263         image/jpeg) image_preview "$cols" "$lines" "$1" ;;
 264         image/gif) generate_preview "$cols" "$lines" "$1" "gif" ;;
 265         image/vnd.djvu) generate_preview "$cols" "$lines" "$1" "djvu" ;;
 266         image/*) generate_preview "$cols" "$lines" "$1" "image" ;;
 267         video/*) generate_preview "$cols" "$lines" "$1" "video" ;;
 268         audio/*) generate_preview "$cols" "$lines" "$1" "audio" ;;
 269         application/font*|application/*opentype|font/*) generate_preview "$cols" "$lines" "$1" "font" ;;
 270         */*office*|*/*document*|*/*msword|*/*ms-excel) generate_preview "$cols" "$lines" "$1" "office" ;;
 271         application/zip) fifo_pager unzip -l "$1" ;;
 272         text/troff)
 273             if exists man; then
 274                 fifo_pager man -Pcat -l "$1"
 275             else
 276                 fifo_pager pager "$1"
 277             fi ;;
 278         *) handle_ext "$1" "$3" "$4" ;;
 279     esac
 280 }
 281
 282 handle_ext() {
 283     case "$2" in
 284         epub) generate_preview "$cols" "$lines" "$1" "epub" ;;
 285         pdf) generate_preview "$cols" "$lines" "$1" "pdf" ;;
 286         gz|bz2) fifo_pager tar -tvf "$1" ;;
 287         md) if exists glow; then
 288                 fifo_pager glow -s dark "$1"
 289             elif exists lowdown; then
 290                 fifo_pager lowdown -Tterm "$1"
 291             else
 292                 fifo_pager pager "$1"
 293             fi ;;
 294         htm|html|xhtml)
 295             if exists w3m; then
 296                 fifo_pager w3m "$1"
 297             elif exists lynx; then
 298                 fifo_pager lynx "$1"
 299             elif exists elinks; then
 300                 fifo_pager elinks "$1"
 301             else
 302                 fifo_pager pager "$1"
 303             fi ;;
 304         7z|a|ace|alz|arc|arj|bz|cab|cpio|deb|jar|lha|lz|lzh|lzma|lzo\
 305         |rar|rpm|rz|t7z|tar|tbz|tbz2|tgz|tlz|txz|tZ|tzo|war|xpi|xz|Z)
 306             if exists atool; then
 307                 fifo_pager atool -l "$1"
 308             elif exists bsdtar; then
 309                 fifo_pager bsdtar -tvf "$1"
 310             fi ;;
 311         *) if [ "$3" = "bin" ]; then
 312                fifo_pager print_bin_info "$1"
 313            else
 314                fifo_pager pager "$1"
 315            fi ;;
 316     esac
 317 }
 318
 319 preview_file() {
 320     clear
 321     # Trying to use pistol if it's available.
 322     if [ "$NNN_PISTOL" -ne 0 ] && exists pistol; then
 323         fifo_pager pistol "$1"
 324         return
 325     fi
 326
 327     # Trying to use scope.sh if it's available.
 328     if [ "$NNN_SCOPE" -ne 0 ] && exists scope.sh; then
 329         fifo_pager scope.sh "$1" "$cols" "$lines" "$(mktemp -d)" "True"
 330         return
 331     fi
 332
 333     # Use QuickLook if it's available.
 334     if [ -n "$QUICKLOOK" ]; then
 335         stat "$1" && f="$(wslpath -w "$1")" && "$QLPATH" "$f" &
 336         return
 337     fi
 338
 339     # Detecting the exact type of the file: the encoding, mime type, and extension in lowercase.
 340     encoding="$(file -bL --mime-encoding -- "$1")"
 341     mimetype="$(file -bL --mime-type -- "$1")"
 342     ext="${1##*.}"
 343     [ -n "$ext" ] && ext="$(printf "%s" "${ext}" | tr '[:upper:]' '[:lower:]')"
 344     lines=$(tput lines)
 345     cols=$(tput cols)
 346
 347     # Otherwise, falling back to the defaults.
 348     if [ -d "$1" ]; then
 349         cd "$1" || return
 350         if [ "$NNN_ICONLOOKUP" -ne 0 ] && [ -f "$(dirname "$0")"/.iconlookup ]; then
 351             [ "$NNN_SPLIT" = v ] && BSTR="\n"
 352             # shellcheck disable=SC2012
 353             ls -F --group-directories-first | head -n "$((lines - 3))" | "$(dirname "$0")"/.iconlookup -l "$cols" -B "$BSTR" -b " "
 354         elif exists tree; then
 355             fifo_pager tree --filelimit "$(find . -maxdepth 1 | wc -l)" -L 3 -C -F --dirsfirst --noreport
 356         elif exists exa; then
 357             exa -G --group-directories-first --colour=always
 358         elif exists eza; then # eza is a community fork of exa (exa is unmaintained)
 359             eza -G --group-directories-first --colour=always
 360         else
 361             fifo_pager ls -F --group-directories-first --color=always
 362         fi
 363         cd ..
 364     elif [ "${encoding#*)}" = "binary" ]; then
 365         handle_mime "$1" "$mimetype" "$ext" "bin"
 366     else
 367         handle_mime "$1" "$mimetype" "$ext"
 368     fi
 369 }
 370
 371 generate_preview() {
 372   if [ -n "$QLPATH" ] && stat "$3"; then
 373         f="$(wslpath -w "$3")" && "$QLPATH" "$f" &
 374   elif [ ! -f "$NNN_PREVIEWDIR/$3.jpg" ] || [ -n "$(find -L "$3" -newer "$NNN_PREVIEWDIR/$3.jpg")" ]; then
 375         mkdir -p "$NNN_PREVIEWDIR/${3%/*}"
 376         case $4 in
 377             audio) ffmpeg -i "$3" -filter_complex "scale=iw*min(1\,min($NNN_PREVIEWWIDTH/iw\,ih)):-1" "$NNN_PREVIEWDIR/$3.jpg" -y ;;
 378             epub) gnome-epub-thumbnailer "$3" "$NNN_PREVIEWDIR/$3.jpg" ;;
 379             font) fontpreview -i "$3" -o "$NNN_PREVIEWDIR/$3.jpg" ;;
 380             gif) if [ -p "$FIFO_UEBERZUG" ] && exists convert; then
 381                     frameprefix="$NNN_PREVIEWDIR/$3/${3##*/}"
 382                     if [ ! -d "$NNN_PREVIEWDIR/$3" ]; then
 383                         mkdir -p "$NNN_PREVIEWDIR/$3"
 384                         convert -coalesce -resize "$NNN_PREVIEWWIDTH"x"$NNN_PREVIEWHEIGHT"\> "$3" "$frameprefix.jpg" ||
 385                         MAGICK_TMPDIR="/tmp" convert -coalesce -resize "$NNN_PREVIEWWIDTH"x"$NNN_PREVIEWHEIGHT"\> "$3" "$frameprefix.jpg"
 386                     fi
 387                     frames=$(($(find "$NNN_PREVIEWDIR/$3" | wc -l) - 2))
 388                     [ $frames -lt 0 ] && return
 389                     while true; do
 390                         for i in $(seq 0 $frames); do
 391                             image_preview "$1" "$2" "$frameprefix-$i.jpg"
 392                             sleep 0.1
 393                         done
 394                     done &
 395                     printf "%s" "$!" > "$PREVIEWPID"
 396                     return
 397                  elif exists mpv; then
 398                     video_preview "$1" "$2" "$3" 1
 399                     return
 400                  else
 401                     image_preview "$1" "$2" "$3"
 402                     return
 403                  fi ;;
 404             image) if exists convert; then
 405                        convert "$3" -flatten -resize "$NNN_PREVIEWWIDTH"x"$NNN_PREVIEWHEIGHT"\> "$NNN_PREVIEWDIR/$3.jpg"
 406                    else
 407                        image_preview "$1" "$2" "$3" && return
 408                    fi ;;
 409             office) libreoffice --convert-to jpg "$3" --outdir "$NNN_PREVIEWDIR/${3%/*}"
 410                     filename="$(printf "%s" "${3##*/}" | cut -d. -f1)"
 411                     mv "$NNN_PREVIEWDIR/${3%/*}/$filename.jpg" "$NNN_PREVIEWDIR/$3.jpg" ;;
 412             pdf) pdftoppm -jpeg -f 1 -singlefile "$3" "$NNN_PREVIEWDIR/$3" ;;
 413             djvu) ddjvu -format=ppm -page=1 "$3" "$NNN_PREVIEWDIR/$3.jpg" ;;
 414             video) video_preview "$1" "$2" "$3" && return ;;
 415         esac
 416     fi
 417     if [ -f "$NNN_PREVIEWDIR/$3.jpg" ]; then
 418         image_preview "$1" "$2" "$NNN_PREVIEWDIR/$3.jpg"
 419     else
 420         fifo_pager print_bin_info "$3"
 421     fi
 422 } >/dev/null 2>&1
 423
 424 image_preview() {
 425     clear
 426     exec >/dev/tty
 427     if [ "$NNN_TERMINAL" = "kitty" ] && [ -z "$NNN_PREVIEWIMGPROG" ]; then
 428         kitty +kitten icat --silent --scale-up --place "$1"x"$2"@0x0 --transfer-mode=stream --stdin=no "$3" &
 429     elif [ "$NNN_TERMINAL" = "wezterm" ] && [ -z "$NNN_PREVIEWIMGPROG" ]; then
 430         wezterm imgcat "$3" &
 431     elif exists ueberzug && { [ -z "$NNN_PREVIEWIMGPROG" ] || [ "$NNN_PREVIEWIMGPROG" = "ueberzug" ] ;}; then
 432         ueberzug_layer "$1" "$2" "$3" && return
 433     elif exists catimg   && { [ -z "$NNN_PREVIEWIMGPROG" ] || [ "$NNN_PREVIEWIMGPROG" = "catimg" ] ;}; then
 434         catimg "$3" &
 435     elif exists viu      && { [ -z "$NNN_PREVIEWIMGPROG" ] || [ "$NNN_PREVIEWIMGPROG" = "viu" ] ;}; then
 436         viu -t "$3" &
 437     elif exists chafa    && { [ -z "$NNN_PREVIEWIMGPROG" ] || [ "$NNN_PREVIEWIMGPROG" = "chafa" ] ;}; then
 438         chafa "$3" &
 439     elif exists img2sixel && { [ -z "$NNN_PREVIEWIMGPROG" ] || [ "$NNN_PREVIEWIMGPROG" = "img2sixel" ] ;}; then
 440         img2sixel -p16 -g "$3" &
 441     else
 442         fifo_pager print_bin_info "$3" && return
 443     fi
 444     printf "%s" "$!" > "$PREVIEWPID"
 445 }
 446
 447 video_preview() {
 448     clear
 449     exec >/dev/tty
 450     if type mpv >/dev/null 2>&1 ; then
 451         if [ "$4" -eq 1 ]; then # not gif
 452             mpv --no-config --really-quiet --vo=sixel --profile=sw-fast --loop-file --mute=yes --start="10%" --length=4 "$3" &
 453         else
 454             mpv --no-config --really-quiet --vo=sixel --profile=sw-fast --loop-file --mute=yes "$3" &
 455         fi
 456     else
 457         ffmpegthumbnailer -m -s0 -i "$3" -o "$NNN_PREVIEWDIR/$3.jpg" || rm "$NNN_PREVIEWDIR/$3.jpg" &
 458     fi
 459     printf "%s" "$!" > "$PREVIEWPID"
 460 }
 461
 462 ueberzug_layer() {
 463     [ -f "$POSOFFSET" ] && read -r x y < "$POSOFFSET"
 464     printf '{"action": "add", "identifier": "nnn_ueberzug", "x": %d, "y": %d, "width": "%d", "height": "%d", "scaler": "fit_contain", "path": "%s"}\n'\
 465         "${x:-0}" "${y:-0}" "$1" "$2" "$3" > "$FIFO_UEBERZUG"
 466 }
 467
 468 ueberzug_remove() {
 469     printf '{"action": "remove", "identifier": "nnn_ueberzug"}\n' > "$FIFO_UEBERZUG"
 470 }
 471
 472 winch_handler() {
 473     clear
 474     pidkill "$PREVIEWPID"
 475     if [ -p "$FIFO_UEBERZUG" ]; then
 476         pkill -f "tail --follow $FIFO_UEBERZUG"
 477         tail --follow "$FIFO_UEBERZUG" | ueberzug layer --silent --parser json &
 478     fi
 479     preview_file "$(cat "$CURSEL")"
 480 }
 481
 482 preview_fifo() {
 483     while read -r selection; do
 484         if [ -n "$selection" ]; then
 485             pidkill "$PREVIEWPID"
 486             [ -p "$FIFO_UEBERZUG" ] && ueberzug_remove
 487             [ "$selection" = "close" ] && break
 488             preview_file "$selection"
 489             printf "%s" "$selection" > "$CURSEL"
 490         fi
 491     done < "$NNN_FIFO"
 492     sleep 0.1 # make sure potential preview by winch_handler is killed
 493     pkill -P "$$"
 494 }
 495
 496 if [ "$PREVIEW_MODE" -eq 1 ] 2>/dev/null; then
 497     if [ "$NNN_TERMINAL" != "kitty" ] && exists ueberzug; then
 498         mkfifo "$FIFO_UEBERZUG"
 499         tail --follow "$FIFO_UEBERZUG" | ueberzug layer --silent --parser json &
 500     fi
 501
 502     preview_file "$PWD/$1"
 503     preview_fifo & WAITPID=$!
 504     printf "%s" "$!" > "$FIFOPID"
 505     printf "%s" "$PWD/$1" > "$CURSEL"
 506     trap 'winch_handler' WINCH
 507     trap 'rm "$PREVIEWPID" "$CURSEL" "$FIFO_UEBERZUG" "$FIFOPID" "$POSOFFSET" 2>/dev/null' INT HUP EXIT
 508     while kill -s 0 $WAITPID; do
 509       wait $WAITPID 2>/dev/null
 510     done
 511     exit 0
 512 else
 513     if [ ! -r "$NNN_FIFO" ]; then
 514         prompt "No FIFO available! (\$NNN_FIFO='$NNN_FIFO')\nPlease read Usage in '$0'."
 515     elif [ "$KITTY_WINDOW_ID" ] && [ -z "$TMUX" ] && [ -z "$KITTY_LISTEN_ON" ]; then
 516         prompt "\$KITTY_LISTEN_ON not set!\nPlease read Usage in '$0'."
 517     else
 518         toggle_preview "$1" &
 519     fi
 520 fi