refactoration

main
Matthew Butterick 7 years ago
parent c1684e82ee
commit dd55973dd8

@ -1,236 +1,206 @@
#lang pitfall/racket
(require "reference.rkt" "object.rkt" "page.rkt" "vector.rkt" "color.rkt")
(provide PDFDocument)
(require "reference.rkt" "object.rkt" "page.rkt" "vector.rkt" "color.rkt")
(define mixed% (color-mixin (vector-mixin object%)))
(define PDFDocument
;; actually is an instance of readable.Stream, which is an input port
(class (color-mixin (vector-mixin object%))
(init-field [(@options options) (mhash)])
(let ([output-file (hash-ref @options 'out "outrkt.pdf")])
(super-new))
; list of byte chunks to push onto
; simulates interface of stream.readable
(field [(@byte-strings byte-strings) empty])
;; PDF version
(field [(@version version) 1.3])
;; Whether streams should be compressed
(field [(@compress compress) (hash-ref @options 'compress #t)])
(field [(@_pageBuffer _pageBuffer) null])
(field [(@_pageBufferStart _pageBufferStart) 0])
;; The PDF object store
(field [(@_offsets _offsets) null])
(field [(@_waiting _waiting) 0])
(field [(@_ended _ended) #f])
(field [(@_offset _offset) 0])
(field [(@_root _root) (@ref
(mhash 'Type "Catalog"
'Pages (@ref
(mhash 'Type "Pages"
'Count 0
'Kids empty))))])
;; The current page
(field [(@page page) #f])
;; other fields, moved up from below
;; (why is this necessary? order seems to matter)
(field [(@x x) 0])
(field [(@y y) 0])
;; todo
(class mixed% ; actually is an instance of readable.Stream, which is an input port
(init-field [options (mhash)])
(super-new)
(field [byte-strings empty] ; list of byte chunks to push onto; simulates interface of stream.readable
[version 1.3] ; PDF version
[compress (hash-ref options 'compress #t)] ; Whether streams should be compressed
[_pageBuffer null]
[_pageBufferStart 0]
[_offsets null] ; The PDF object store
[_waiting 0]
[_ended #f]
[_offset 0]
[_root (ref this
(mhash 'Type "Catalog"
'Pages (ref this
(mhash 'Type "Pages"
'Count 0
'Kids empty))))] ; top object
[page #f] ; The current page
[x 0]
[y 0]
[info (mhash
'Producer "PitfallKit"
'Creator "PitfallKit"
'CreationDate (seconds->date (if (test-mode)
0
(current-seconds)) #f))] ; Initialize the metadata
[op #f] ; for `pipe`
[_info #f]) ; for `end`
;; Initialize mixins
(· this initColor)
(· this initVector)
#;(@initFonts)
#;(@initText)
#;(@initImages)
;; Initialize the metadata
(field [(@info info) (mhash
'Producer "PitfallKit"
'Creator "PitfallKit"
'CreationDate (seconds->date (if (test-mode)
0
(current-seconds)) #f))])
(when (hash-ref @options 'info #f)
(for ([(key val) (in-hash (hash-ref @options 'info))])
(hash-set! @info key val)))
#;(· this initFonts) ; todo
#;(· this initText) ; todo
#;(· this initImages) ; todo
(as-methods
addPage
flushPages
ref
push
_write
addContent
_refEnd
pipe
end
_finalize)
(for ([(key val) (in-hash (hash-ref options 'info (hash)))]) ; if no 'info key, nothing will be copied from (hash)
(hash-set! info key val))
;; Write the header
;; PDF version
(@_write (format "%PDF-~a" @version))
;; 4 binary chars, as recommended by the spec
(_write this (format "%PDF-~a" version)) ; PDF version
(let ([c (integer->char #xFF)])
(@_write (string-append "%" (string c c c c))))
(_write this (string-append "%" (string c c c c)))) ; 4 binary chars, as recommended by the spec
;; Add the first page
(unless (not (hash-ref @options 'autoFirstPage #t))
(@addPage))
;; todo
;;mixin = (methods) =>
;;for name, method of methods
;;this::[name] = method
;; todo
;; Load mixins
;; (in racket this is handled automatically in the class decl)
;mixin require './mixins/color'
;mixin require './mixins/vector'
;mixin require './mixins/fonts'
;mixin require './mixins/text'
;mixin require './mixins/images'
;mixin require './mixins/annotations'
(unless (not (hash-ref options 'autoFirstPage #t))
(addPage this))))
(public [@addPage addPage])
(define (@addPage [options @options])
;; end the current page if needed
(unless (hash-ref @options 'bufferPages #f)
(@flushPages))
;; create a page object
(set! @page (make-object PDFPage this options))
(push-end! @_pageBuffer @page)
;; add the page to the object store
(define pages (· @_root data Pages data))
(hash-update! pages 'Kids (λ (val) (cons (· @page dictionary) val)) null)
(hash-update! pages 'Count add1)
;; reset x and y coordinates
(set! @x (· @page margins left))
(set! @y (· @page margins top))
;; flip PDF coordinate system so that the origin is in
;; the top left rather than the bottom left
(set-field! _ctm this '(1 0 0 1 0 0))
(send this transform 1 0 0 -1 0 (· @page height))
#;(@emit "pageAdded") ; from eventemitter interface
this
)
(public [@flushPages flushPages])
(define (@flushPages)
;; this local variable exists so we're future-proof against
;; reentrant calls to flushPages.
(define pages @_pageBuffer)
(set! @_pageBuffer empty)
(+= @_pageBufferStart (length pages))
(·map end pages))
;; every js function argument is 'undefined' by default
;; so even a function defined without default values
;; can be called without arguments
(public [@ref ref])
(define (@ref [data (mhash)])
(define ref (make-object PDFReference this (add1 (length @_offsets)) data))
(push-end! @_offsets #f) ; placeholder for this object's offset once it is finalized
(++ @_waiting)
ref)
(public [@push push])
(define (@push chunk)
(push! @byte-strings chunk))
(public [@_write _write])
(define (@_write data)
(let ([data (if (not (isBuffer? data))
(newBuffer (string-append data "\n"))
data)])
(@push data)
(+= @_offset (buffer-length data))))
(public [@addContent addContent])
(define (@addContent data)
(send @page write data)
this)
(define/public (_refEnd ref)
(set! @_offsets (for/list ([(offset idx) (in-indexed @_offsets)])
(if (= (· ref id) (add1 idx))
(· ref offset)
offset)))
(-- @_waiting)
(if (and (zero? @_waiting) @_ended)
(@_finalize)
(set! @_ended #f)))
(field [op #f])
(define/public (pipe port)
(set! op port))
(field [(@_info _info) #f])
(define/public (end)
(@flushPages)
(set! @_info (@ref))
(for ([(key val) (in-hash @info)])
;; upgrade string literal to String struct
(hash-set! (· @_info data) key (if (string? val) (String val) val)))
(· @_info end)
;; todo: fonts
;; for name, font of @_fontFamilies
;; font.finalize()
(· @_root end)
(· @_root data Pages end)
(if (zero? @_waiting)
(@_finalize)
(set! @_ended #t))
#t)
(public (@_finalize _finalize))
(define (@_finalize [fn #f])
;; generate xref
(define xRefOffset @_offset)
(@_write "xref")
(@_write (format "0 ~a" (add1 (length @_offsets))))
(@_write "0000000000 65535 f ")
(for ([offset (in-list @_offsets)])
(@_write (string-append
(define/contract (addPage this [options-arg (· this options)])
(() (hash?) . ->*m . object?)
;; end the current page if needed
(unless (hash-ref (· this options) 'bufferPages #f)
(send this flushPages))
;; create a page object
(set-field! page this (make-object PDFPage this options-arg))
(push-end-field! _pageBuffer this (· this page))
;; add the page to the object store
(define pages (· this _root data Pages data))
(hash-update! pages 'Kids (curry cons (· this page dictionary)) null)
(hash-update! pages 'Count add1)
;; reset x and y coordinates
(set-field! x this (· this page margins left))
(set-field! y this (· this page margins top))
;; flip PDF coordinate system so that the origin is in
;; the top left rather than the bottom left
(set-field! _ctm this default-ctm-value)
(send this transform 1 0 0 -1 0 (· this page height))
#;(@emit "pageAdded") ; from eventemitter interface
this)
(define/contract (flushPages this)
(->m list?)
;; this local variable exists so we're future-proof against
;; reentrant calls to flushPages.
(define pages (· this _pageBuffer))
(set-field! _pageBuffer this empty)
(increment-field! _pageBufferStart this (length pages))
(·map end pages))
;; every js function argument is 'undefined' by default
;; so even a function defined without default values
;; can be called without arguments
(define/contract (ref this [data (mhash)])
(() (hash?) . ->*m . (is-a?/c PDFReference))
(define newref (make-object PDFReference this (add1 (length (· this _offsets))) data))
(push-end-field! _offsets this #f) ; placeholder for this object's offset once it is finalized
(increment-field! _waiting this)
newref)
(define/contract (push this chunk)
(any/c . ->m . void?)
(push-field! byte-strings this chunk))
(define/contract (_write this data)
(any/c . ->m . void?)
(let ([data (if (not (isBuffer? data))
(newBuffer (string-append data "\n"))
data)])
(push this data)
(void (increment-field! _offset this (buffer-length data)))))
(define/contract (addContent this data)
(any/c . ->m . object?)
(send (· this page) write data)
this)
(define/contract (_refEnd this ref)
((is-a?/c PDFReference) . ->m . void?)
(set-field! _offsets this (for/list ([(offset idx) (in-indexed (· this _offsets))])
(if (= (· ref id) (add1 idx))
(· ref offset)
offset)))
(increment-field! _waiting this -1)
(if (and (zero? (· this _waiting)) (· this _ended))
(· this _finalize)
(set-field! _ended this #f)))
(define/contract (pipe this port)
(port? . ->m . void?)
(set-field! op this port))
(define/contract (end this)
(->m boolean?)
(flushPages this)
(set-field! _info this (ref this))
(for ([(key val) (in-hash (· this info))])
;; upgrade string literal to String struct
(hash-set! (· this _info data) key (if (string? val) (String val) val)))
(· this _info end)
;; todo: fonts
;; for name, font of @_fontFamilies
;; font.finalize()
(· this _root end)
(· this _root data Pages end)
(if (zero? (· this _waiting))
(· this _finalize)
(set-field! _ended this #t))
#t)
(define/contract (_finalize this [fn #f])
(() ((or/c procedure? #f)) . ->*m . void?)
;; generate xref
(define xref-offset (· this _offset))
(_write this "xref")
(_write this (format "0 ~a" (add1 (length (· this _offsets)))))
(_write this "0000000000 65535 f ")
(for ([offset (in-list (· this _offsets))])
(_write this (string-append
(~r offset #:min-width 10 #:pad-string "0")
" 00000 n ")))
;; trailer
(@_write "trailer")
;; todo: make `PDFObject:convert` a static method
(@_write (convert
(mhash 'Size (add1 (length @_offsets))
'Root @_root
'Info @_info)))
(@_write "startxref")
(@_write (number->string xRefOffset))
(@_write "%%EOF")
;; end the stream
;; in node you (@push null) which signals to the stream
;; to copy to its output port
;; here we'll do it manually
(copy-port (open-input-bytes (apply bytes-append (reverse @byte-strings))) op)
(close-output-port op))))
#;(module+ test
(define doc (new PDFDocument))
(require rackunit racket/file)
(define ob (open-output-bytes))
(send doc pipe ob)
(check-true (send doc end))
(define result-str (get-output-bytes ob))
(define fn "out")
(with-output-to-file (string-append fn ".pdf")
(λ () (display result-str)) #:exists 'replace)
(check-equal? (file->bytes (string-append fn ".pdf")) (file->bytes (string-append fn " copy.pdf")))
(display (bytes->string/latin-1 result-str)))
;; trailer
(_write this "trailer")
(_write this (convert
(mhash 'Size (add1 (length (· this _offsets)))
'Root (· this _root)
'Info (· this _info))))
(_write this "startxref")
(_write this (number xref-offset))
(_write this "%%EOF")
;; end the stream
;; in node you (@push null) which signals to the stream
;; to copy to its output port
;; here we'll do it manually
(copy-port (open-input-bytes (apply bytes-append (reverse (· this byte-strings)))) (· this op))
(close-output-port (· this op)))

@ -1,5 +1,5 @@
#lang pitfall/racket
(provide vector-mixin)
(provide vector-mixin default-ctm-value)
(define (vector-mixin [% mixin-tester%])
(class %

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