From c0940152182dae66a285522399f25db40338aa48 Mon Sep 17 00:00:00 2001
From: Matthew Butterick <mb@mbtype.com>
Date: Thu, 18 May 2017 17:06:43 -0700
Subject: [PATCH] ok

---
 pitfall/pitfall/reference.rkt | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/pitfall/pitfall/reference.rkt b/pitfall/pitfall/reference.rkt
index 682ca200..552b54b3 100644
--- a/pitfall/pitfall/reference.rkt
+++ b/pitfall/pitfall/reference.rkt
@@ -2,10 +2,20 @@
 (require "object.rkt" "zlib.rkt")
 (provide PDFReference)
 
+(define-subclass object% (Chunks)
+  (super-new)
+  (define chunks null)
+  (define/public (append-chunk chunk)
+    (set! chunks (append chunks (list chunk))))
+  )
+
+(define-subclass Chunks (CompressedChunks)
+  (super-new))
+
+
 (define-subclass object% (PDFReference document id [data (mhash)])
   (super-new)
   (field [gen 0]
-         [i-wanna-be-deflated #f]
          [compress (and (· document compress) (not (hash-ref data 'Filter #f)))]
          [chunks empty]
          [offset #f])
@@ -28,7 +38,6 @@
                     chunk-in
                     (newBuffer (string-append chunk-in "\n"))))
   (hash-ref! (· this data) 'Length 0)
-  (when (· this compress) (set-field! i-wanna-be-deflated this #t))
   (push-end-field! chunks this chunk)
   (hash-update! (· this data) 'Length (curry + (buffer-length chunk)))
   (callback))
@@ -37,7 +46,7 @@
 (define/contract (end this [chunk #f])
   (() ((or/c any/c #f)) . ->*m . void?)
 
-  (when (· this i-wanna-be-deflated)
+  (when (and (· this compress) (positive? (length (· this chunks))))
     (define deflated-chunk (deflate (apply bytes-append (· this chunks))))
     (set-field! chunks this (list deflated-chunk))
     (hash-set*! (· this data)
@@ -56,7 +65,7 @@
     (when (positive? (length this-chunks))
       (send this-doc _write "stream")
       (for ([chunk (in-list this-chunks)])
-        (send this-doc _write chunk))
+           (send this-doc _write chunk))
       (send this-doc _write "\nendstream")))
 
   (send* this-doc