(define pffi-init (lambda () #t))

(define pffi-size-of
  (lambda (type)
    (cond ((eq? type 'int8) 1) ; FIXME
          ((eq? type 'uint8) 1) ; FIXME
          ((eq? type 'int16) 2) ; FIXME
          ((eq? type 'uint16) 2) ;FIXME
          ((eq? type 'int32) 4) ; FIXME
          ((eq? type 'uint32) 4) ; FIXME
          ((eq? type 'int64) 8) ; FIXME
          ((eq? type 'uint64) 8) ; FIXME
          ((eq? type 'char) size-of-bool)
          ((eq? type 'unsigned-char) size-of-bool)
          ((eq? type 'short) size-of-short)
          ((eq? type 'unsigned-short) size-of-unsigned-short)
          ((eq? type 'int) size-of-int)
          ((eq? type 'unsigned-int) size-of-unsigned-int)
          ((eq? type 'long) size-of-long)
          ((eq? type 'unsigned-long) size-of-unsigned-long)
          ((eq? type 'float) size-of-float)
          ((eq? type 'double) size-of-double)
          ((eq? type 'pointer) size-of-pointer)
          (else (error "Can not get size of unknown type" type)))))

(define pffi-shared-object-load
  (lambda (header path)
    (open-shared-library path)))

(define pffi-pointer-null
  (lambda ()
    pointer-null))

(define pffi-pointer-null?
  (lambda (pointer)
    (pointer-null? pointer)))

(define pffi-pointer-allocate
  (lambda (size)
    (malloc size)))

(define pffi-pointer?
  (lambda (object)
    (pointer? object)))

(define pffi-pointer-free
  (lambda (pointer)
    (free pointer)))

(define pffi-pointer-set!
  (lambda (pointer type offset value)
    (cond ((equal? type 'int8) (pointer-set-c-int8! pointer offset value))
          ((equal? type 'uint8) (pointer-set-c-uint8! pointer offset value))
          ((equal? type 'int16) (pointer-set-c-int16! pointer offset value))
          ((equal? type 'uint16) (pointer-set-c-uint16! pointer offset value))
          ((equal? type 'int32) (pointer-set-c-int32! pointer offset value))
          ((equal? type 'uint32) (pointer-set-c-uint32! pointer offset value))
          ((equal? type 'int64) (pointer-set-c-int64! pointer offset value))
          ((equal? type 'uint64) (pointer-set-c-uint64! pointer offset value))
          ((equal? type 'char) (pointer-set-c-char! pointer offset (char->integer value)))
          ((equal? type 'short) (pointer-set-c-short! pointer offset value))
          ((equal? type 'unsigned-short) (pointer-set-c-short! pointer offset value)) ;; FIXME
          ((equal? type 'int) (pointer-set-c-int! pointer offset value))
          ((equal? type 'unsigned-int) (pointer-set-c-int! pointer offset value)) ;; FIXME
          ((equal? type 'long) (pointer-set-c-long! pointer offset value))
          ((equal? type 'unsigned-long) (pointer-set-c-long! pointer offset value)) ;; FIXME
          ((equal? type 'float) (pointer-set-c-float! pointer offset value))
          ((equal? type 'double) (pointer-set-c-double! pointer offset value))
          ((equal? type 'void) (pointer-set-c-pointer! pointer offset value))
          ((equal? type 'pointer) (pointer-set-c-pointer! pointer offset value)))))

(define pffi-pointer-get
  (lambda (pointer type offset)
    (cond ((equal? type 'int8) (pointer-ref-c-int8 pointer offset))
          ((equal? type 'uint8) (pointer-ref-c-uint8 pointer offset))
          ((equal? type 'int16) (pointer-ref-c-int16 pointer offset))
          ((equal? type 'uint16) (pointer-ref-c-uint16 pointer offset))
          ((equal? type 'int32) (pointer-ref-c-int32 pointer offset))
          ((equal? type 'uint32) (pointer-ref-c-uint32 pointer offset))
          ((equal? type 'int64) (pointer-ref-c-int64 pointer offset))
          ((equal? type 'uint64) (pointer-ref-c-uint64 pointer offset))
          ((equal? type 'char) (integer->char (pointer-ref-c-signed-char pointer offset)))
          ((equal? type 'short) (pointer-ref-c-signed-short pointer offset))
          ((equal? type 'unsigned-short) (pointer-ref-c-unsigned-short pointer offset))
          ((equal? type 'int) (pointer-ref-c-signed-int pointer offset))
          ((equal? type 'unsigned-int) (pointer-ref-c-unsigned-int pointer offset))
          ((equal? type 'long) (pointer-ref-c-signed-long pointer offset))
          ((equal? type 'unsigned-long) (pointer-ref-c-unsigned-long pointer offset))
          ((equal? type 'float) (pointer-ref-c-float pointer offset))
          ((equal? type 'double) (pointer-ref-c-double pointer offset))
          ((equal? type 'void) (pointer-ref-c-pointer pointer offset))
          ((equal? type 'pointer) (pointer-ref-c-pointer pointer offset)))))

(define pffi-string->pointer
  (lambda (string-content)
    (let ((pointer (pffi-pointer-allocate (+ (string-length string-content) 1)))
          (index 0))
      (string-for-each
        (lambda (c)
          (pffi-pointer-set! pointer 'char (* index (pffi-size-of 'char)) c)
          (set! index (+ index 1)))
        string-content)
      pointer)))

(define pffi-pointer->string
  (lambda (pointer)
    (pointer->string pointer)))

(define pffi-type->native-type
  (lambda (type)
    (cond ((equal? type 'int8) 'int8_t)
          ((equal? type 'uint8) 'uint8_t)
          ((equal? type 'int16) 'int16_t)
          ((equal? type 'uint16) 'uint16_t)
          ((equal? type 'int32) 'int32_t)
          ((equal? type 'uint32) 'uint32_t)
          ((equal? type 'int64) 'int64_t)
          ((equal? type 'uint64) 'uint64_t)
          ((equal? type 'char) 'char)
          ((equal? type 'unsigned-char) 'char)
          ((equal? type 'short) 'short)
          ((equal? type 'unsigned-short) 'unsigned-short)
          ((equal? type 'int) 'int)
          ((equal? type 'unsigned-int) 'unsigned-int)
          ((equal? type 'long) 'long)
          ((equal? type 'unsigned-long) 'unsigned-long)
          ((equal? type 'float) 'float)
          ((equal? type 'double) 'double)
          ((equal? type 'pointer) 'void*)
          ((equal? type 'string) 'char*)
          ((equal? type 'void) 'void)
          ((equal? type 'callback) 'callback)
          (else (error "pffi-type->native-type -- No such pffi type" type)))))

(define-syntax pffi-define
  (syntax-rules ()
    ((pffi-define scheme-name shared-object c-name return-type argument-types)
     (define scheme-name
       (make-c-function shared-object
                        (pffi-type->native-type return-type)
                        c-name
                        (map pffi-type->native-type argument-types))))))

(define-syntax pffi-define-callback
  (syntax-rules ()
    ((_ scheme-name return-type argument-types procedure)
     (define scheme-name
       (make-c-callback (pffi-type->native-type return-type)
                        (map pffi-type->native-type argument-types)
                        procedure)))))