(import chicken scheme)
(use irregex srfi-13)

(define *replacements*
  `(((: "/*" (*? any) "*/") . "")
    ("GLAPI " . "")
    ("#if.*\n" . "")
    ("#ifndef.*\n" . "")
    ("#elif.*\n" . "")
    ("#else\n" . "")
    ("#endif.*\n" . "")
    ("extern.*\n" . "")
    ("ptrdiff_t" . ,(cond-expand
                      (x86-64 "int64_t")
                      (else "int32_t")))
    ("GL_APIENTRY " . "")
    ("GL_APICALL " . "")
    ("APIENTRYP " . "*")
    ("APIENTRY " . "")
    ("\n}\n" . "")
    ("#include.*\n" . "")
    ("#define GL_VERSION.*\n" . "")
    ("#define GL_ES_VERSION.*\n" . "")
    ("#define [^G].*\n" . "")
    ((: "*const*") . "**")
    ((: newline (*? (or alpha numeric ("()*") space)) "PFNGL" (*? any) eol) . "")
    ("#endif .*\n" . "")
    ("\n\n" . "\n")
    ("typedef long int int64_t;\ntypedef unsigned long int uint64_t;\ntypedef long long int int64_t;\ntypedef unsigned long long int uint64_t;\ntypedef long int int32_t;\ntypedef long long int int64_t;\ntypedef unsigned long long int uint64_t;\ntypedef __int32 int32_t;\ntypedef __int64 int64_t;\ntypedef unsigned __int64 uint64_t;\ntypedef uint64_t GLuint64;\ntypedef int64_t GLint64;" .
     "typedef uint64_t GLuint64;\ntypedef int64_t GLint64;")
    ("khronos_ssize_t" . "signed int")
    ("khronos_intptr_t" . "signed int")
    ("khronos_float_t" . "float")
    ("khronos_" . "")
    ("typedef unsigned char GLboolean;" . "typedef bool GLboolean;" )))

(define (gl-translate file)
  (call-with-output-file "gl.h"
    (lambda (output)
      (call-with-input-file file
        (lambda (input)
          (let ([h (read-string #f input)])
            (let loop ((str h) (replacements *replacements*))
              (if (null? replacements)
                  (write-string str #f output)
                  (loop (irregex-replace/all (caar replacements) str
                                             (cdar replacements))
                        (cdr replacements))))))))))