sixel: Export $FZF_PREVIEW_TOP to the preview command (#2544)

So that it can determine if it should subtract 1 from $FZF_PREVIEW_LINES
to avoid scrolling issue of Sixel image that touches the bottom of the
screen.

1 files changed, 20 insertions, 7 deletions

diff --git a/bin/fzf-preview.sh b/bin/fzf-preview.sh
index ae4c6521..d72cd2d4 100755
--- a/bin/fzf-preview.sh
+++ b/bin/fzf-preview.sh
@@ -13,14 +13,14 @@ if [[ $# -ne 1 ]]; then
 fi
 
 file=${1/#\~\//$HOME/}
-type=$(file --mime-type "$file")
-
-dim=${FZF_PREVIEW_COLUMNS}x${FZF_PREVIEW_LINES}
-if [[ $dim = x ]]; then
-  dim=$(stty size | awk '{print $2 "x" $1}')
-fi
+type=$(file --dereference --mime -- "$file")
 
 if [[ ! $type =~ image/ ]]; then
+  if [[ $type =~ =binary ]]; then
+    file "$1"
+    exit
+  fi
+
   # Sometimes bat is installed as batcat.
   if command -v batcat > /dev/null; then
     batname="batcat"
@@ -32,7 +32,19 @@ if [[ ! $type =~ image/ ]]; then
   fi
 
   ${batname} --style="${BAT_STYLE:-numbers}" --color=always --pager=never -- "$file"
-elif [[ $KITTY_WINDOW_ID ]]; then
+  exit
+fi
+
+dim=${FZF_PREVIEW_COLUMNS}x${FZF_PREVIEW_LINES}
+if [[ $dim = x ]]; then
+  dim=$(stty size < /dev/tty | awk '{print $2 "x" $1}')
+elif ! [[ $KITTY_WINDOW_ID ]] && (( FZF_PREVIEW_TOP + FZF_PREVIEW_LINES == $(stty size < /dev/tty | awk '{print $1}') )); then
+  # Avoid scrolling issue when the Sixel image touches the bottom of the screen
+  # * https://github.com/junegunn/fzf/issues/2544
+  dim=${FZF_PREVIEW_COLUMNS}x$((FZF_PREVIEW_LINES - 1))
+fi
+
+if [[ $KITTY_WINDOW_ID ]]; then
   # 1. 'memory' is the fastest option but if you want the image to be scrollable,
   #    you have to use 'stream'.
   #
@@ -42,6 +54,7 @@ elif [[ $KITTY_WINDOW_ID ]]; then
   kitty icat --clear --transfer-mode=memory --stdin=no --place="$dim@0x0" "$file" | sed '$d' | sed $'$s/$/\e[m/'
 elif command -v chafa > /dev/null; then
   chafa -f sixel -s "$dim" "$file"
+  # Add a new line character so that fzf can display multiple images in the preview window
   echo
 else
   file "$file"