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;;; Copyright (C) 2016-2017 by nee <nee-git@hidamari.blue>
;;; this is a part of gutter and licensed under to AGPL3.0
;;; see https://gnu.org/l/agpl-3.0
(define-module (download)
  #:export (with-download
            download
            test-download))

(define (success? return-code)
  (= 0 return-code))

(define (download download-path url)
  (if (not (file-exists? download-path))
      (and (success? (system* "wget" "-O" download-path url))
           download-path)
      download-path))

(define (test-download download-path url)
  "useful for testcases"
  (copy-file (string-append "test/download/" (basename url))
             download-path)
  download-path)

(define (with-download download-path url callback)
  (download download-path url)
  (call-with-input-file download-path callback))