cache and constraint preview dimensions (#910)

* cache and constraint preview dimensions

* cache subdirectory

* optional caching

* revert to ext for pdf/epub

diff --git a/plugins/preview-tui-ext b/plugins/preview-tui-ext
index 09a6bd8cc13dea64dd5b5b5510e4ef2cec88f284..9d0fd60f012a6e76d1b8b56493b09ba5ae7d6fe4 100755 (executable)
--- a/plugins/preview-tui-ext
+++ b/plugins/preview-tui-ext
@@ -47,7 +47,7 @@
 #
 #     $ NNN_FIFO=/tmp/nnn.fifo nnn
 #
-#   Then in `nnn`, launch the `preview-tui` plugin.
+#   Then in `nnn`, launch the `preview-tui-ext` plugin.
 #
 #   If you provide the same NNN_FIFO to all nnn instances, there will be a
 #   single common preview window. If you provide different FIFO path (e.g.
@@ -76,6 +76,10 @@ USE_PISTOL="${USE_PISTOL:-0}"
 PAGER="${PAGER:-less -P?n -R}"
 ARCHIVES="$(echo "$NNN_ARCHIVE" | sed 's/.*(\(.*\)).*/\1/;s/|/ /g')"
 TMPDIR="${TMPDIR:-/tmp}"
+# Consider setting NNN_PREVIEWDIR to $XDG_CACHE_DIR if you want to keep previews on disk between reboots
+NNN_PREVIEWDIR="${NNN_PREVIEWDIR:-$TMPDIR}/nnn/previews"
+NNN_PREVIEWWIDTH="${NNN_PREVIEWWIDTH:-1920}"
+NNN_PREVIEWHEIGHT="${NNN_PREVIEWHEIGHT:-1080}"
 NUMPREVIEWTUI="$(($(find "$TMPDIR" -maxdepth 1 -name 'nnn-preview-tui-pagerpid*' 2>/dev/null | wc -l) + 1))"
 PAGERPID="$TMPDIR/nnn-preview-tui-pagerpid.$NUMPREVIEWTUI"
 GIFPID="$TMPDIR/nnn-preview-tui-gifpid.$NUMPREVIEWTUI"
@@ -131,7 +135,7 @@ print_bin_info() {
     fi
 }
 
-preview_file () {
+preview_file() {
     clear
     # Trying to use pistol if it's available.
     if [ "$USE_PISTOL" -ne 0 ] && exists pistol; then
@@ -168,12 +172,14 @@ preview_file () {
             fifo_pager ls --color=always
         fi
     elif [ "$encoding" = "binary" ]; then
-        if [ "$ext" = "gif" ]; then
-            generate_preview "$cols" "$lines" "$1" "gif"
-        elif [ "${mimetype#*/}" = "x-xcf" ]; then
-            generate_preview "$cols" "$lines" "$1" "xcf"
-        elif [ "${mimetype%%/*}" = "image" ]; then
-            image_preview "$cols" "$lines" "$1"
+        if [ "${mimetype%%/*}" = "image" ]; then
+            if [ "${mimetype#*/}" = "gif" ] && exists convert; then
+                generate_preview "$cols" "$lines" "$1" "gif"
+            elif [ ! "${mimetype#*/}" = "jpeg" ]; then
+                generate_preview "$cols" "$lines" "$1" "image"
+            else
+                image_preview "$cols" "$lines" "$1"
+            fi
         elif [ "${mimetype%%/*}" = "audio" ] && exists ffmpeg; then
             generate_preview "$cols" "$lines" "$1" "audio"
         elif [ "${mimetype%%/*}" = "video" ] && exists ffmpegthumbnailer; then
@@ -226,19 +232,19 @@ preview_file () {
 }
 
 generate_preview() {
-    if [ ! -f "$TMPDIR/$3.jpg" ]; then
-        mkdir -p "$TMPDIR/${3%/*}"
+  if [ ! -f "$NNN_PREVIEWDIR/$3.jpg" ] || [ -n "$(find -L "$3" -newer "$NNN_PREVIEWDIR/$3.jpg")" ]; then
+        mkdir -p "$NNN_PREVIEWDIR/${3%/*}"
         case $4 in
-            audio) ffmpeg -i "$3" "$TMPDIR/$3.jpg" -y >/dev/null 2>&1 ;;
-            epub) gnome-epub-thumbnailer "$3" "$TMPDIR/$3.jpg" >/dev/null 2>&1 ;;
-            font) fontpreview -i "$3" -o "$TMPDIR/$3.jpg" >/dev/null 2>&1 ;;
+            audio) ffmpeg -i "$3" -filter_complex "scale=iw*min(1\,min($NNN_PREVIEWWIDTH/iw\,ih)):-1" "$NNN_PREVIEWDIR/$3.jpg" -y >/dev/null 2>&1 ;;
+            epub) gnome-epub-thumbnailer "$3" "$NNN_PREVIEWDIR/$3.jpg" >/dev/null 2>&1 ;;
+            font) fontpreview -i "$3" -o "$NNN_PREVIEWDIR/$3.jpg" >/dev/null 2>&1 ;;
             gif) if exists ueberzug && exists convert || [ "$TERMINAL" = "kitty" ]; then
-                    if [ ! -d "$TMPDIR/$3" ]; then
-                        mkdir -p "$TMPDIR/$3"
-                        convert -coalesce "$3" "$TMPDIR/$3/${3##*/}.jpg"
+                    if [ ! -d "$NNN_PREVIEWDIR/$3" ]; then
+                        mkdir -p "$NNN_PREVIEWDIR/$3"
+                        convert -coalesce -resize "$NNN_PREVIEWWIDTH"x"$NNN_PREVIEWHEIGHT"\> "$3" "$NNN_PREVIEWDIR/$3/${3##*/}.jpg"
                     fi
                         while true; do
-                            for frame in $(find "$TMPDIR/$3"/*.jpg | sort -V); do
+                            for frame in $(find "$NNN_PREVIEWDIR/$3"/*.jpg | sort -V); do
                                 image_preview "$1" "$2" "$frame"
                                 sleep 0.1
                             done
@@ -250,20 +256,16 @@ generate_preview() {
                     image_preview "$1" "$2" "$3"
                     return
                  fi ;;
-            office) libreoffice --convert-to jpg "$3" --outdir "$TMPDIR/${3%/*}" > /dev/null 2>&1
+            image) convert "$3" -flatten -resize "$NNN_PREVIEWWIDTH"x"$NNN_PREVIEWHEIGHT"\> "$NNN_PREVIEWDIR/$3.jpg" ;;
+            office) libreoffice --convert-to jpg "$3" --outdir "$NNN_PREVIEWDIR/${3%/*}" > /dev/null 2>&1
                     filename="$(echo "${3##*/}" | cut -d. -f1)"
-                    mv "$TMPDIR/${3%/*}/$filename.jpg" "$TMPDIR/$3.jpg" ;;
-            pdf) pdftoppm -jpeg -f 1 -singlefile "$3" "$TMPDIR/$3" >/dev/null 2>&1 ;;
-            video) if ! ffmpegthumbnailer -i "$3" -o "$TMPDIR/$3.jpg" -s 0 -q 10 >/dev/null 2>&1; then
-                       rm "$TMPDIR/$3.jpg"
-                       fifo_pager print_bin_info "$3"
-                       return
-                   fi ;;
-            xcf) convert -flatten "$3" "$TMPDIR/$3.jpg" ;;
+                    mv "$NNN_PREVIEWDIR/${3%/*}/$filename.jpg" "$NNN_PREVIEWDIR/$3.jpg" ;;
+            pdf) pdftoppm -jpeg -f 1 -singlefile "$3" "$NNN_PREVIEWDIR/$3" >/dev/null 2>&1 ;;
+            video) ffmpegthumbnailer -m -s0 -i "$3" -o "$NNN_PREVIEWDIR/$3.jpg" >/dev/null 2>&1 || rm "$NNN_PREVIEWDIR/$3.jpg" ;;
         esac
     fi
-    if [ -f "$TMPDIR/$3.jpg" ]; then
-        image_preview "$1" "$2" "$TMPDIR/$3.jpg"
+    if [ -f "$NNN_PREVIEWDIR/$3.jpg" ]; then
+        image_preview "$1" "$2" "$NNN_PREVIEWDIR/$3.jpg"
     else
         fifo_pager print_bin_info "$3"
     fi
@@ -307,10 +309,6 @@ ueberzug_refresh() {
     preview_fifo &
     wait
 }
-if [ "$TERMINAL" != "kitty" ] && [ "$PREVIEW_MODE" ] && exists ueberzug; then
-    trap 'ueberzug_refresh' WINCH
-    trap 'rm "$FIFO_UEBERZUG" "$PAGERPID" "$GIFPID" "$CURSEL"' INT HUP EXIT
-fi
 
 preview_fifo() {
     # use cat instead of 'exec <' to avoid issues with dash shell
@@ -338,6 +336,8 @@ if [ "$PREVIEW_MODE" ]; then
 
     if [ "$TERMINAL" != "kitty" ] && exists ueberzug; then
         mkfifo "$FIFO_UEBERZUG"
+        trap 'ueberzug_refresh' WINCH
+        trap 'rm "$FIFO_UEBERZUG" "$PAGERPID" "$GIFPID" "$CURSEL"' INT HUP EXIT
         tail --follow "$FIFO_UEBERZUG" | ueberzug layer --silent --parser json &
     fi