scripts/t: handle arbitrary depths

scripts/t

@@ -1,11 +1,25 @@
 #!/bin/sh
 
 # compact version of tree
+
+# max directories depth
+level=$(echo "$@" | sed -nE 's/.*-L ?([0-9]).*/\1/p')
+# indentatiof of leaf directory
+begin=$(printf "%$((level - 2))s" | sed 's/ /│   /g')
+# indentation of leaf files
+line=$(printf "%$((level - 1))s" | sed 's/ /│   /g')
+
+# limit to 6 files and add ellipses
 res=$(tree --dirsfirst --noreport -L 2 -C "$@" \
-| awk '/^├|└/{l1=0} /^│/{l1+=1} {if (l1 <= 5){print $0} if(l1 == 6){print "│   ├── ..."}}' \
+| awk -v begin="$begin" -v line="$line" '
+    ($0 ~ "^"begin"├|└") {count=0}
+    ($0 ~ "^"line) {count+=1}
+    {if (count <= 5){print $0} if(count == 6){print line"├── ..."}}
+  ' \
 | sed 's/ / /g')
 
+# use a pager when output doesn't fit the screen
 if test $(printf "%s\n" "$res" | wc -l) -gt $(tput lines)
-then printf "%s\n" "$res" | less -RSicX
+then printf "%s\n" "$res" | $PAGER -RSicX
 else printf "%s\n" "$res"
 fi