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#lang pitfall/racket
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(require "jpeg.rkt" "png.rkt")
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(provide PDFImage)
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(define PDFImage
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(class object%
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(super-new)
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(as-methods
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open)))
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(define/contract (open this src label)
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(any/c any/c . ->m . bytes?)
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(define data (cond
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[(isBuffer? src) src]
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;;else if src instanceof ArrayBuffer
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;;data = new Buffer(new Uint8Array(src))
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[(regexp-match #rx"^data:.+;base64,(.*)$" src)
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(void)] ;; base64 ; todo
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[else (file->bytes src)]))
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(cond
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[(equal? (subbytes data 0 2) (bytes #xff #xd8))
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'doJpeg]
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[(equal? (subbytes data 0 4) (apply bytes (cons #x89 (map char->integer '(#\P #\N #\G)))))
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'doPNG]
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[else (raise-argument-error 'PDFImage-open "valid image format" src)]))
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