1 files changed, 112 insertions, 0 deletions
diff --git a/srt2vtt/ui.scm b/srt2vtt/ui.scm
new file mode 100644
index 0000000..607c49e
--- /dev/null
+++ b/srt2vtt/ui.scm
@@ -0,0 +1,112 @@
+;;; srt2vtt --- SRT to WebVTT converter
+;;; Copyright © 2015 David Thompson <davet@gnu.org>
+;;;
+;;; srt2vtt is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or
+;;; (at your option) any later version.
+;;;
+;;; srt2vtt is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+;;; General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with srt2vtt.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (srt2vtt ui)
+  #:use-module (ice-9 format)
+  #:use-module (ice-9 match)
+  #:use-module (srfi srfi-1)
+  #:use-module (srfi srfi-37)
+  #:use-module (srt2vtt subrip)
+  #:use-module (srt2vtt webvtt)
+  #:export (main))
+
+(define (show-help-and-exit)
+  (format #t "Usage: srt2vtt [OPTIONS]
+Convert SubRip formatted subtitles to WebVTT format.~%")
+  (display "
+  -h, --help             display this help and exit")
+  (display "
+  -v, --version          display version and exit")
+  (display "
+  -i, --input=FILE-NAME  read input from FILE-NAME")
+  (display "
+  -o, --output=FILE-NAME write output to FILE-NAME")
+  (newline)
+  (exit 0))
+
+(define (show-version-and-exit)
+  (format #t "srt2vtt 0.1~%")
+  (exit 0))
+
+(define (show-usage-and-exit)
+  (format #t "Try `srt2vtt --help' for more information.~%")
+  (exit 1))
+
+(define (show-wrong-args-and-exit)
+  (format #t "Invalid arguments~%")
+  (show-usage-and-exit))
+
+(define %default-args
+  `((input . ,(current-input-port))
+    (output . ,(current-output-port))))
+
+(define %options
+  (list (option '(#\h "help") #f #f
+                (lambda (opt name arg args)
+                  (show-help-and-exit)))
+        (option '(#\v "version") #f #f
+                (lambda (opt name arg args)
+                  (show-version-and-exit)))
+        (option '(#\i "input") #t #f
+                (lambda (opt name arg args)
+                  (alist-cons 'input arg args)))
+        (option '(#\o "output") #t #f
+                (lambda (opt name arg args)
+                  (alist-cons 'output arg args)))))
+
+(define (make-call-with-port-or-file file-proc)
+  "Create a new procedure that accepts two arguments: a port or file,
+and a procedure.  When the returned procedure is called with a port as
+the first argument, the second argument is simply applied with that
+port.  If the first argument is a string, the second argument is
+applied with the port corresponding to the file name contained in the
+string as opened by FILE-PROC."
+  (lambda (port-or-file proc)
+    (if (port? port-or-file)
+        (proc port-or-file)
+        (file-proc port-or-file proc))))
+
+(define call-with-port-or-input-file
+  (make-call-with-port-or-file call-with-input-file))
+
+(define call-with-port-or-output-file
+  (make-call-with-port-or-file call-with-output-file))
+
+(define (parse-opts args)
+  "Parse the list of ARGS and return a list of option/value pairs.
+When an option isn't specified in ARGS, it defaults to the value in
+'%default-args'."
+  (args-fold args
+             %options
+             (lambda (opt name arg args)
+               (error "Unrecognized option '~a'" name))
+             (lambda (arg args)
+               (error "Extraneous argument '~a'" arg))
+             %default-args))
+
+(define (convert input-port output-port)
+  "Read the SubRip formatted subtitles from INPUT-PORT and write the
+WebVTT equivalents to OUTPUT-PORT."
+  (write-webvtts (read-subrips input-port) output-port))
+
+(define (main args)
+  "srt2vtt entry point."
+  (let ((opts (parse-opts args)))
+    (call-with-port-or-input-file (assoc-ref opts 'input)
+      (lambda (input-port)
+        (call-with-port-or-output-file (assoc-ref opts 'output)
+          (lambda (output-port)
+            (convert input-port output-port)))))))