#lang racket/base

(require (for-syntax racket/base)
         racket/path)


(provide exn:fail:audio
         exn:fail:audio?
         exn:fail:audio-code
         raise-audio-error
         make-audio-error-code
         exn-audio-code
         )

(struct exn:fail:audio exn:fail
  (code source line)
  #:transparent)

(define exn-audio-code exn:fail:audio-code)

(define (audio-codes)
  '(no-decoder no-encoder
    file-not-found
    invalid-audio-file
    no-audio-reader
    audio-file-corrupt
    audio-error))

(define (make-audio-code code)
  (if (symbol? code)
      (letrec ((f (λ (l)
                    (if (null? (cdr l))
                        (car l)
                        (if (eq? (car l) code)
                            code
                            (f (cdr l)))))))
        (f (audio-codes)))
      (make-audio-code (string->symbol (format "~a" code)))))

(define (make-audio-error-code c)
  (make-audio-code c))


(define (raise-audio-error* code source line message . args)
  (displayln (format "raise-audio-error*: code=~a source=~a line=~a message=~a args=~a" code source line message args))
  (let* ((msg (apply format (cons message args)))
         (src* (file-name-from-path (build-path source)))
         (msg* (format "~a at ~a, line ~a" msg src* line)))
      (raise (exn:fail:audio msg*
                             (current-continuation-marks)
                             (make-audio-code code)
                             source
                             line))))

(define-syntax (raise-audio-error stx)
  (syntax-case stx ()
    ((_ code message ...)
     (let ((src (syntax-source stx))
           (line (syntax-line stx)))
       #`(raise-audio-error* code '#,src '#,line message ...)))))

(define (test x)
  (if (> x 10)
      (raise-audio-error 'file-notd-found "File not found: ~a" "c:/muziek/a.flac")
      #t))