From 5b08f07136c68154ad018c2e4d074f70193ca6dd Mon Sep 17 00:00:00 2001
From: Matthew Butterick <mb@mbtype.com>
Date: Thu, 27 Dec 2018 10:42:53 -0800
Subject: [PATCH] Revert "finish structifying font"

This reverts commit 9e6c9c57f3c03ac7112342f8dd0c7f9937a2bbcc.
---
 pitfall/pitfall/embedded-font.rkt | 310 +++++++++++++++---------------
 pitfall/pitfall/fonts.rkt         |   7 +-
 pitfall/pitfall/standard-font.rkt |   2 +
 3 files changed, 159 insertions(+), 160 deletions(-)

diff --git a/pitfall/pitfall/embedded-font.rkt b/pitfall/pitfall/embedded-font.rkt
index befe82b7..ae949d5e 100644
--- a/pitfall/pitfall/embedded-font.rkt
+++ b/pitfall/pitfall/embedded-font.rkt
@@ -3,14 +3,15 @@
   (for-syntax racket/base)
   "core.rkt"
   "reference.rkt"
+  racket/class
   racket/match
   racket/string
   racket/format
   racket/list
   racket/dict
   sugar/unstable/dict
+  "font.rkt"
   fontland)
-(provide make-embedded-font)
 
 #|
 approximates
@@ -30,149 +31,142 @@ https://github.com/mbutterick/pdfkit/blob/master/lib/font/embedded.coffee
    (for/list ([code (in-list codePoints)])
      (~r code #:base 16 #:min-width 4 #:pad-string "0"))))
 
-(struct $embedded-font $font (font subset unicode widths scale) #:mutable)
-
-(define (make-embedded-font font id)
-  [define subset (create-subset font)]
-  ;; we make `unicode` and `width` fields integer-keyed hashes not lists
-  ;; because they offer better random access and growability 
-  [define unicode (mhasheqv 0 '(0))] ; always include the missing glyph (gid = 0)
-  [define widths (mhasheqv 0 (glyph-advance-width (get-glyph font 0)))]
-  ;; always include the width of the missing glyph (gid = 0)
-  [define name (font-postscript-name font)]
-  [define scale (/ 1000 (font-units-per-em font))]
-  [define ascender (* (font-ascent font) scale)]
-  [define descender (* (font-descent font) scale)]
-  [define bbox (font-bbox font)]
-  [define line-gap (* (font-linegap font) scale)]
-  (define new-font
-    ($embedded-font name id ascender descender line-gap bbox
-                    #f ; no dictionary
-                    #f ; not embedded
-                    'embfont-embed-placeholder 'embfont-encode-placeholder 'embfont-string-width-placeholder
-                    font subset unicode widths scale))
-  (define (embed-proc) (embfont-embed new-font))
-  (set-$font-embed-proc! new-font embed-proc)
-  (define (encode-proc str [options #f]) (embfont-encode new-font str options))
-  (set-$font-encode-proc! new-font encode-proc)
-  (define (string-width-proc str size [options #f]) (embfont-string-width new-font str size options))
-  (set-$font-string-width-proc! new-font string-width-proc)
-  new-font)
-
-(define (embfont-embed font)
-  ;; no CFF support
-  
-  (define isCFF #false) #;(is-a? subset CFFSubset)
-  (define font-file (make-ref))
-
-  (when isCFF
-    (dict-set! font-file 'Subtype 'CIDFontType0C))
-
-  (ref-write font-file (get-output-bytes (encode-to-port ($embedded-font-subset font))))
-  (ref-end font-file)
-
-  (define family-class (if (has-table? ($embedded-font-font font) 'OS/2)
-                           (floor (/ (hash-ref (get-OS/2-table ($embedded-font-font font)) 'sFamilyClass) 256)) ; >> 8
-                           0))
-  ;; font descriptor flags
-  (match-define (list FIXED_PITCH SERIF SYMBOLIC SCRIPT _UNUSED NONSYMBOLIC ITALIC)
-    (map (λ (x) (expt 2 x)) (range 7)))
-
-  (define flags (sum-flags
-                 [(not (zero? (hash-ref (get-post-table ($embedded-font-font font)) 'isFixedPitch))) FIXED_PITCH]
-                 [(<= 1 family-class 7) SERIF]
-                 [#t SYMBOLIC] ; assume the font uses non-latin characters
-                 [(= family-class 10) SCRIPT]
-                 [(hash-ref (hash-ref (get-head-table ($embedded-font-font font)) 'macStyle) 'italic) ITALIC]))
-
-  ;; generate a random tag (6 uppercase letters. 65 is the char code for 'A')
-  (when (test-mode) (random-seed 0))
-  (define tag (list->string (for/list ([i (in-range 6)])
-                              (integer->char (random 65 (+ 65 26))))))
-  (define name (string->symbol (string-append tag "+" (font-postscript-name ($embedded-font-font font)))))
-  (define bbox (font-bbox ($embedded-font-font font)))
-  (define descriptor (make-ref
-                      (mhash
-                       'Type 'FontDescriptor
-                       'FontName name
-                       'Flags flags
-                       'FontBBox (map (λ (x) (* ($embedded-font-scale font) x))
-                                      (bbox->list bbox))
-                       'ItalicAngle (font-italic-angle ($embedded-font-font font))
-                       'Ascent ($font-ascender font)
-                       'Descent ($font-descender font)
-                       'CapHeight (* (or (font-cap-height ($embedded-font-font font)) (font-ascent ($embedded-font-font font))) ($embedded-font-scale font))
-                       'XHeight (* (or (font-x-height ($embedded-font-font font)) 0) ($embedded-font-scale font))
-                       'StemV 0)))
-
-  (dict-set! descriptor (if isCFF 'FontFile3 'FontFile2) font-file)
-  (ref-end descriptor)
-
-  (define descendant-font (make-ref
-                           (mhash
-                            'Type 'Font
-                            'Subtype (string->symbol (string-append "CIDFontType" (if isCFF "0" "2")))
-                            'BaseFont name
-                            'CIDSystemInfo
-                            (mhash
-                             'Registry "Adobe"
-                             'Ordering "Identity"
-                             'Supplement 0)
-                            'FontDescriptor descriptor
-                            'W (list 0 (for/list ([idx (in-range (length (hash-keys ($embedded-font-widths font))))])
-                                         (hash-ref ($embedded-font-widths font) idx (λ () (error 'embed (format "hash key ~a not found" idx)))))))))
-  (ref-end descendant-font)
+#;(define EmbeddedFont
+  (class PDFFont
+    (init-field font id)
+    (field [subset (create-subset font)]
+           ;; we make `unicode` and `width` fields integer-keyed hashes not lists
+           ;; because they offer better random access and growability 
+           [unicode (mhash 0 '(0))] ; always include the missing glyph (gid = 0)
+           [widths (mhash 0 (glyph-advance-width (get-glyph font 0)))]
+           ;; always include the width of the missing glyph (gid = 0)
+           [name (font-postscript-name font)]
+           [scale (/ 1000 (font-units-per-em font))])
+    (super-new [ascender (* (font-ascent font) scale)]
+               [descender (* (font-descent font) scale)]
+               [bbox (font-bbox font)]
+               [line-gap (* (font-linegap font) scale)])
+
+    (inherit-field [@ascender ascender]
+                   [@descender descender]
+                   [@dictionary dictionary])
+
+    (define/override (string-width string size [features #f])
+      ; #f disables features ; null enables default features ; list adds features
+      (hash-ref! width-cache
+                 (list string size (and features (sort features symbol<?)))
+                 (λ ()
+                   (define run (layout font string features))
+                   (define width (glyphrun-advance-width run))
+                   (define scale (/ size (+ (font-units-per-em font) 0.0)))
+                   (* width scale))))
+
+    ;; called from text.rkt
+    (define/override (encode text [features #f])
+      (define glyphRun (layout font text features))
+      (define glyphs (glyphrun-glyphs glyphRun))
+      (define positions (glyphrun-positions glyphRun))
+      (define-values (subset-idxs new-positions)
+        (for/lists (idxs posns)
+                   ([(g i) (in-indexed glyphs)]
+                    [posn (in-list positions)])
+          (define gid (subset-add-glyph! subset (glyph-id g)))
+          (define subset-idx (to-hex gid))
+          (set-glyph-position-advance-width! posn (glyph-advance-width g))
+
+          (hash-ref! widths gid (λ () (glyph-position-advance-width posn)))
+          (hash-ref! unicode gid (λ () (glyph-codepoints g)))
+
+          (scale-glyph-position! posn scale)
+          (values subset-idx posn)))
+      (list subset-idxs new-positions))
+
+
+    (define/override (embed)
+      ;; no CFF support
+      (define isCFF #false) #;(is-a? subset CFFSubset)
+      (define font-file (make-ref))
+
+      (when isCFF
+        (dict-set! font-file 'Subtype 'CIDFontType0C))
+
+      (ref-write font-file (get-output-bytes (encode-to-port subset)))
+      (ref-end font-file)
+
+      (define family-class (if (has-table? font 'OS/2)
+                               (floor (/ (hash-ref (get-OS/2-table font) 'sFamilyClass) 256)) ; >> 8
+                               0))
+      ;; font descriptor flags
+      (match-define (list FIXED_PITCH SERIF SYMBOLIC SCRIPT _UNUSED NONSYMBOLIC ITALIC)
+        (map (λ (x) (expt 2 x)) (range 7)))
+
+      (define flags (sum-flags
+                     [(not (zero? (hash-ref (get-post-table font) 'isFixedPitch))) FIXED_PITCH]
+                     [(<= 1 family-class 7) SERIF]
+                     [#t SYMBOLIC] ; assume the font uses non-latin characters
+                     [(= family-class 10) SCRIPT]
+                     [(hash-ref (hash-ref (get-head-table font) 'macStyle) 'italic) ITALIC]))
+
+      ;; generate a random tag (6 uppercase letters. 65 is the char code for 'A')
+      (when (test-mode) (random-seed 0))
+      (define tag (list->string (for/list ([i (in-range 6)])
+                                  (integer->char (random 65 (+ 65 26))))))
+      (define name (string->symbol (string-append tag "+" (font-postscript-name font))))
+      (define bbox (font-bbox font))
+      (define descriptor (make-ref
+                          (mhash
+                           'Type 'FontDescriptor
+                           'FontName name
+                           'Flags flags
+                           'FontBBox (map (λ (x) (* scale x))
+                                          (bbox->list bbox))
+                           'ItalicAngle (font-italic-angle font)
+                           'Ascent @ascender
+                           'Descent @descender
+                           'CapHeight (* (or (font-cap-height font) (font-ascent font)) scale)
+                           'XHeight (* (or (font-x-height font) 0) scale)
+                           'StemV 0)))
+
+      (dict-set! descriptor (if isCFF 'FontFile3 'FontFile2) font-file)
+      (ref-end descriptor)
+
+      (define descendant-font (make-ref
+                               (mhash
+                                'Type 'Font
+                                'Subtype (string->symbol (string-append "CIDFontType" (if isCFF "0" "2")))
+                                'BaseFont name
+                                'CIDSystemInfo
+                                (mhash
+                                 'Registry "Adobe"
+                                 'Ordering "Identity"
+                                 'Supplement 0)
+                                'FontDescriptor descriptor
+                                'W (list 0 (for/list ([idx (in-range (length (hash-keys widths)))])
+                                             (hash-ref widths idx (λ () (error 'embed (format "hash key ~a not found" idx)))))))))
+      (ref-end descendant-font)
       
-  [dict-set! ($font-dictionary font) 'Type 'Font]
-  [dict-set! ($font-dictionary font) 'Subtype 'Type0]
-  [dict-set! ($font-dictionary font) 'BaseFont name]
-  [dict-set! ($font-dictionary font) 'Encoding 'Identity-H]
-  [dict-set! ($font-dictionary font) 'DescendantFonts (list descendant-font)]
-  [dict-set! ($font-dictionary font) 'ToUnicode (to-unicode-cmap font)]
-
-  (ref-end ($font-dictionary font)))
-
-(define (embfont-encode font text [features #f])
-  (define glyphRun (layout ($embedded-font-font font) text features))
-  (define glyphs (glyphrun-glyphs glyphRun))
-  (define positions (glyphrun-positions glyphRun))
-  (define-values (subset-idxs new-positions)
-    (for/lists (idxs posns)
-               ([(g i) (in-indexed glyphs)]
-                [posn (in-list positions)])
-      (define gid (subset-add-glyph! ($embedded-font-subset font) (glyph-id g)))
-      (define subset-idx (to-hex gid))
-      (set-glyph-position-advance-width! posn (glyph-advance-width g))
-
-      (hash-ref! ($embedded-font-widths font) gid (λ () (glyph-position-advance-width posn)))
-      (hash-ref! ($embedded-font-unicode font) gid (λ () (glyph-codepoints g)))
-
-      (scale-glyph-position! posn ($embedded-font-scale font))
-      (values subset-idx posn)))
-  (list subset-idxs new-positions))
-
-(define (embfont-string-width font string size [features #f])
-  ; #f disables features ; null enables default features ; list adds features
-  (hash-ref! width-cache
-             (list string size (and features (sort features symbol<?)))
-             (λ ()
-               (define run (layout ($embedded-font-font font) string features))
-               (define width (glyphrun-advance-width run))
-               (define scale (/ size (+ (font-units-per-em ($embedded-font-font font)) 0.0)))
-               (* width scale))))
-
-(define (to-unicode-cmap font)
-  (define cmap (make-ref))
-  (define entries
-    (for/list ([idx (in-range (length (hash-keys ($embedded-font-unicode font))))])
-      (define codepoints (hash-ref ($embedded-font-unicode font) idx))
-      (define encoded ; encode codePoints to utf16
-        ;; todo: full utf16 support. for now just utf8
-        (for/list ([value (in-list codepoints)])
-          (to-hex value)))
-      (format "<~a>" (string-join encoded " "))))
-
-  (define unicode-cmap-str #<<HERE
+      [dict-set! @dictionary 'Type 'Font]
+      [dict-set! @dictionary 'Subtype 'Type0]
+      [dict-set! @dictionary 'BaseFont name]
+      [dict-set! @dictionary 'Encoding 'Identity-H]
+      [dict-set! @dictionary 'DescendantFonts (list descendant-font)]
+      [dict-set! @dictionary 'ToUnicode (toUnicodeCmap)]
+
+      (ref-end @dictionary))
+
+
+    (define/public (toUnicodeCmap)
+      (define cmap (make-ref))
+      (define entries
+        (for/list ([idx (in-range (length (hash-keys unicode)))])
+          (define codepoints (hash-ref unicode idx))
+          (define encoded ; encode codePoints to utf16
+            ;; todo: full utf16 support. for now just utf8
+            (for/list ([value (in-list codepoints)])
+              (to-hex value)))
+          (format "<~a>" (string-join encoded " "))))
+
+      (define unicode-cmap-str #<<HERE
 /CIDInit /ProcSet findresource begin
 12 dict begin
 begincmap
@@ -194,21 +188,21 @@ CMapName currentdict /CMap defineresource pop
 end
 end
 HERE
-    )
+        )
   
-  (ref-write cmap (format unicode-cmap-str (to-hex (sub1 (length entries))) (string-join entries " ")))
-  (ref-end cmap)
-  cmap)
+      (ref-write cmap (format unicode-cmap-str (to-hex (sub1 (length entries))) (string-join entries " ")))
+      (ref-end cmap)
+      cmap)))
 
 #;(module+ test
-    (require rackunit fontland sugar/unstable/js)
-    (define f (open-font "../ptest/assets/charter.ttf"))
-    (define ef (make-object EmbeddedFont #f f #f))
-    (check-equal? (send ef string-width "f" 1000) 321.0)
-    (check-equal? (· ef ascender) 980)
-    (check-equal? (· ef descender) -238)
-    (check-equal? (· ef line-gap) 0)
-    (check-equal? (bbox->list (· ef bbox)) '(-161 -236 1193 963))
-    (define H-gid 41)
-    (check-equal? (· ef widths) (mhash 0 278))
-    (check-equal? (glyph-advance-width (get-glyph (· ef font) H-gid)) 738))
\ No newline at end of file
+  (require rackunit fontland sugar/unstable/js)
+  (define f (open-font "../ptest/assets/charter.ttf"))
+  (define ef (make-object EmbeddedFont #f f #f))
+  (check-equal? (send ef string-width "f" 1000) 321.0)
+  (check-equal? (· ef ascender) 980)
+  (check-equal? (· ef descender) -238)
+  (check-equal? (· ef line-gap) 0)
+  (check-equal? (bbox->list (· ef bbox)) '(-161 -236 1193 963))
+  (define H-gid 41)
+  (check-equal? (· ef widths) (mhash 0 278))
+  (check-equal? (glyph-advance-width (get-glyph (· ef font) H-gid)) 738))
\ No newline at end of file
diff --git a/pitfall/pitfall/fonts.rkt b/pitfall/pitfall/fonts.rkt
index 42aa3d1f..43bd7ed7 100644
--- a/pitfall/pitfall/fonts.rkt
+++ b/pitfall/pitfall/fonts.rkt
@@ -4,12 +4,15 @@
   "reference.rkt"
   racket/match
   sugar/unstable/dict
+  racket/class
   "standard-font.rkt"
+  "font.rkt"
   fontland
   "embedded-font.rkt")
 
 (provide (all-defined-out))
 
+
 (define (make-font-ref font)
   (unless ($font-dictionary font)
     (set-$font-dictionary! font (make-ref)))
@@ -27,14 +30,14 @@
 (define (PDFFont-open src family id)
   (cond
     [(and (string? src) (standard-font? src)) (make-standard-font src id)]
-    [else
+    #;[else
      (define font
        (cond
          [(string? src) (open-font src)]
          [(path? src) (open-font (path->string src))]
          ;; todo: other font-loading cases
          [else (raise-argument-error 'PDFFont-open "loadable font thingy" src)]))
-     (make-embedded-font font id)]))
+     (make-object EmbeddedFont font id)]))
 
 
 (define (current-line-height doc [include-gap #f])
diff --git a/pitfall/pitfall/standard-font.rkt b/pitfall/pitfall/standard-font.rkt
index 19747f8e..80ed614a 100644
--- a/pitfall/pitfall/standard-font.rkt
+++ b/pitfall/pitfall/standard-font.rkt
@@ -1,8 +1,10 @@
 #lang racket/base
 (require
+  racket/class
   racket/string
   racket/match
   sugar/unstable/dict
+  "font.rkt"
   "core.rkt"
   "reference.rkt"
   fontland