#! /usr/bin/env skint -s

;---------------------------------------------------------------------------------------------
; Skint n.sf precursor compiler (n.sf => n.h)
;---------------------------------------------------------------------------------------------

(import (only (skint hidden) 
  list2? list3?))


(define (path-strip-directory filename)
  (let loop ([l (reverse (string->list filename))] [r '()])
    (cond [(null? l) (list->string r)]
          [(memv (car l) '(#\\ #\/ #\:)) (list->string r)]
          [else (loop (cdr l) (cons (car l) r))])))

(define (path-strip-extension filename)
  (let ([l (reverse (string->list filename))])
    (let ([r (memv #\. l)])
      (if r (list->string (reverse (cdr r))) filename))))

(define (module-name filename)
  (path-strip-extension (path-strip-directory filename)))

(define *prelude* 
"#if defined(__clang__)
#pragma GCC diagnostic ignored \"-Wparentheses-equality\"
#pragma GCC diagnostic ignored \"-Wignored-attributes\"
#pragma GCC diagnostic ignored \"-Wunused-function\"
#pragma GCC diagnostic ignored \"-Wunused-value\"
#pragma GCC diagnostic ignored \"-Woverlength-strings\"
#endif
/* this is for MS headers; shouldn't affect others */
#define _CRT_SECURE_NO_WARNINGS 1

/* standard includes */
#include <stdio.h>
#include <stddef.h>
#include <stdlib.h>
#include <assert.h>
/* extra includes */
#include <math.h>
#include <errno.h>
#include <ctype.h>
#include <string.h>
#include <time.h>

/* standard definitions */
#ifdef NAN_BOXING
#include <stdint.h>
typedef int64_t obj;          /* pointers are this size, higher 16 bits and lower bit zero */
typedef int64_t cxoint_t;     /* same thing, used as integer */
typedef struct {              /* type descriptor */
  const char *tname;          /* name (debug) */
  void (*free)(void*);        /* deallocator */
} cxtype_t;

#define notobjptr(o)          (((cxoint_t)(o) - (cxoint_t)cxg_heap) & cxg_hmask)
#define isobjptr(o)           (!notobjptr(o))
#define notaptr(o)            ((o) & 0xffff000000000001ULL)
#define isaptr(o)             (!notaptr(o))
#else
typedef ptrdiff_t obj;        /* pointers are this size, lower bit zero */
typedef ptrdiff_t cxoint_t;   /* same thing, used as integer */
typedef struct {              /* type descriptor */
  const char *tname;          /* name (debug) */
  void (*free)(void*);        /* deallocator */
} cxtype_t;

#define notobjptr(o)          (((char*)(o) - (char*)cxg_heap) & cxg_hmask)
#define isobjptr(o)           (!notobjptr(o))
#define notaptr(o)            ((o) & 1)
#define isaptr(o)             (!notaptr(o))
#endif

#define obj_from_obj(o)       (o)
#define obj_from_objptr(p)    ((obj)(p))
#define obj_from_size(n)      (((cxoint_t)(n) << 1) | 1)

#define objptr_from_objptr(p) (p)
#define objptr_from_obj(o)    ((obj*)(o))

#define size_from_obj(o)      ((int)((o) >> 1))

#define obj_from_case(n)      obj_from_objptr(cases+(n))
#define case_from_obj(o)      (objptr_from_obj(o)-cases)
#define obj_from_ktrap()      obj_from_size(0x5D56F806)
#define obj_from_void(v)      ((void)(v), obj_from_size(0x6F56DF77))

#define bool_from_obj(o)      (o)
#define bool_from_bool(b)     (b)
#define bool_from_size(s)     (s)

#define void_from_void(v)     (void)(v)
#define void_from_obj(o)      (void)(o)

#define rreserve(m)           if (r + (m) >= cxg_rend) r = cxm_rgc(r, m)
#define hpushptr(p, pt, l)    (hreserve(2, l), *--hp = (obj)(p), *--hp = (obj)(pt), (obj)(hp+1))   
#define hbsz(s)               ((s) + 1) /* 1 extra word to store block size */
#define hreserve(n, l)        ((hp < cxg_heap + (n)) ? hp = cxm_hgc(r, r+(l), hp, n) : hp)
#define hendblk(n)            (*--hp = obj_from_size(n), (obj)(hp+1))
#define hblklen(p)            size_from_obj(((obj*)(p))[-1])
#define hblkref(p, i)         (((obj*)(p))[i])

typedef obj (*cxhost_t)(obj);
typedef struct cxroot_tag {
  int globc; obj **globv;
  struct cxroot_tag *next;
} cxroot_t;

extern obj *cxg_heap;
extern obj *cxg_hp;
extern cxoint_t cxg_hmask;
extern cxroot_t *cxg_rootp;
extern obj *cxm_rgc(obj *regs, size_t needs);
extern obj *cxm_hgc(obj *regs, obj *regp, obj *hp, size_t needs);
extern obj *cxg_regs, *cxg_rend;
extern void cxm_check(int x, char *msg);
extern void *cxm_cknull(void *p, char *msg);
extern int cxg_rc;
extern char **cxg_argv;

/* extra definitions */
")


(define (process-top-form x oport)
  (when (and (list2? x) (symbol? (car x)) (string? (cadr x)))
    (case (car x)
      [(%definition) (display (cadr x) oport) (newline oport)]
      [(%localdef)] ; does not go into n.h
      [(%include)]))) ; all needed includes already included

(define (process-file ifname . ?ofname)
  (define iport (open-input-file ifname)) ; relative to wd, not this script!
  (define oport (if (pair? ?ofname) (open-output-file (car ?ofname)) (current-output-port)))
  (define mname (module-name ifname))
  (display "/* " oport) (display mname oport) 
  (display ".h -- generated via skint nsf2h.ssc " oport) 
  (display (path-strip-directory ifname) oport) 
  (display " */" oport) (newline oport) (newline oport)
  (display *prelude* oport)
  (let loop ([x (read iport)])
    (unless (eof-object? x)
      (process-top-form x oport)
      (loop (read iport))))
  (close-input-port iport)
  (if (pair? ?ofname) (close-output-port oport)))

(define (main args)
  (cond [(list2? args) (process-file (cadr args))]
        [(list3? args) (process-file (cadr args) (caddr args))]
        [else (error "usage: skint nsf2h.ssc INFILE [OUTFILE]" args)]))

; this is not a real #! script, so call main manually
(main (command-line))