/*
  Win32API - Ruby Win32 API Import Facility
*/

#if !defined _MSC_VER && !defined NT
#define  WIN32_LEAN_AND_MEAN
#include <windows.h>
#include <stdio.h>
#endif

#define _T_VOID     0
#define _T_NUMBER   1
#define _T_POINTER  2
#define _T_INTEGER  3

typedef char *ApiPointer();
typedef long  ApiNumber();
typedef void  ApiVoid();
typedef int   ApiInteger();

#include "ruby.h"

typedef struct {
    HANDLE dll;
    HANDLE proc;
    VALUE dllname;
    VALUE import;
    VALUE export;
} Win32API;

static void
Win32API_FreeLibrary(hdll)
    HINSTANCE hdll;
{
    FreeLibrary(hdll);
}

static VALUE
Win32API_initialize(self, dllname, proc, import, export)
    VALUE self;
    VALUE dllname;
    VALUE proc;
    VALUE import;
    VALUE export;
{
    HANDLE hproc;
    HINSTANCE hdll;
    VALUE str;
    VALUE a_import;
    VALUE *ptr;
    char *s;
    int i;
    int len;
    int ex;

    Check_SafeStr(dllname);
    Check_SafeStr(proc);
    hdll = LoadLibrary(RSTRING(dllname)->ptr);
    if (!hdll)
	rb_raise(rb_eRuntimeError, "LoadLibrary: %s\n", RSTRING(dllname)->ptr);
    rb_iv_set(self, "__hdll__", Data_Wrap_Struct(self, 0, Win32API_FreeLibrary, hdll));
    hproc = GetProcAddress(hdll, RSTRING(proc)->ptr);
    if (!hproc) {
	str = rb_str_new3(proc);
	str = rb_str_cat(str, "A", 1);
	hproc = GetProcAddress(hdll, RSTRING(str)->ptr);
	if (!hproc)
	    rb_raise(rb_eRuntimeError, "GetProcAddress: %s or %s\n",
		RSTRING(proc)->ptr, RSTRING(str)->ptr);
    }
    rb_iv_set(self, "__dll__", UINT2NUM((unsigned long)hdll));
    rb_iv_set(self, "__dllname__", dllname);
    rb_iv_set(self, "__proc__", UINT2NUM((unsigned long)hproc));

    a_import = rb_ary_new();
    switch (TYPE(import)) {
      case T_NIL:
	break;
      case T_ARRAY:
	ptr = RARRAY(import)->ptr;
	for (i = 0, len = RARRAY(import)->len; i < len; i++) {
	    Check_SafeStr(ptr[i]);
	    switch (*(char *)RSTRING(ptr[i])->ptr) {
	      case 'N': case 'n': case 'L': case 'l':
		rb_ary_push(a_import, INT2FIX(_T_NUMBER));
		break;
	      case 'P': case 'p':
		rb_ary_push(a_import, INT2FIX(_T_POINTER));
		break;
	      case 'I': case 'i':
		rb_ary_push(a_import, INT2FIX(_T_INTEGER));
		break;
	    }
	}
        break;
      default:
	Check_SafeStr(import);
	s = RSTRING(import)->ptr;
	for (i = 0, len = RSTRING(import)->len; i < len; i++) {
	    switch (*s++) {
	      case 'N': case 'n': case 'L': case 'l':
		rb_ary_push(a_import, INT2FIX(_T_NUMBER));
		break;
	      case 'P': case 'p':
		rb_ary_push(a_import, INT2FIX(_T_POINTER));
		break;
	      case 'I': case 'i':
		rb_ary_push(a_import, INT2FIX(_T_INTEGER));
		break;
	    }
	}
        break;
    }
    rb_iv_set(self, "__import__", a_import);

    if (NIL_P(export)) {
	ex = _T_VOID;
    } else {
	Check_SafeStr(export);
	switch (*RSTRING(export)->ptr) {
	  case 'V': case 'v':
	    ex = _T_VOID;
	    break;
	  case 'N': case 'n': case 'L': case 'l':
	    ex = _T_NUMBER;
	    break;
	  case 'P': case 'p':
	    ex = _T_POINTER;
	    break;
	  case 'I': case 'i':
	    ex = _T_INTEGER;
	    break;
	}
    }
    rb_iv_set(self, "__export__", INT2FIX(ex));

    return Qnil;
}

static VALUE
Win32API_Call(argc, argv, obj)
    int argc;
    VALUE *argv;
    VALUE obj;
{
    VALUE args;

    FARPROC ApiFunction;

    ApiPointer  *ApiFunctionPointer;
    ApiNumber   *ApiFunctionNumber;
    ApiVoid     *ApiFunctionVoid;
    ApiInteger  *ApiFunctionInteger;

    long  lParam;
    char *pParam;

    void *p[16];

    VALUE obj_proc;
    VALUE obj_import;
    VALUE obj_export;
    VALUE import_type;
    int nimport, timport, texport, i;
    int items;

    items = rb_scan_args(argc, argv, "0*", &args);

    obj_proc = rb_iv_get(obj, "__proc__");

    ApiFunction = (FARPROC)NUM2ULONG(obj_proc);

    obj_import = rb_iv_get(obj, "__import__");
    obj_export = rb_iv_get(obj, "__export__");
    nimport = RARRAY(obj_import)->len;
    texport = FIX2INT(obj_export);

    if (items != nimport)
	rb_raise(rb_eRuntimeError, "Wrong number of parameters: expected %d, got %d.\n",
	    nimport, items);

    if (0 < nimport) {
	for (i = 0; i < nimport; i++) {
	    VALUE str;
	    import_type = rb_ary_entry(obj_import, i);
	    timport = FIX2INT(import_type);
	    switch (timport) {
	    case _T_NUMBER:
	    case _T_INTEGER:
		lParam = NUM2ULONG(rb_ary_entry(args, i));
		p[i] = (void *)lParam;
		break;
	    case _T_POINTER:
		str = rb_ary_entry(args, i);
		if (NIL_P(str)) {
		    pParam = 0;
		} else if (FIXNUM_P(str)){
		    pParam = (char *)NUM2ULONG(str);
		} else {
		    Check_Type(str, T_STRING);
		    rb_str_modify(str);
		    pParam = RSTRING(str)->ptr;
		}
		p[i] = (void *)pParam;
		break;
	    }
	}
    }

    switch (texport) {
    case _T_NUMBER:
	ApiFunctionNumber = (ApiNumber *) ApiFunction;
	switch (nimport) {
	case  0:	return INT2NUM(ApiFunctionNumber(p[0]));
	case  1:	return INT2NUM(ApiFunctionNumber(p[0], p[1]));
	case  2:	return INT2NUM(ApiFunctionNumber(p[0], p[1], p[2]));
	case  3:	return INT2NUM(ApiFunctionNumber(p[0], p[1], p[2], p[3]));
	case  4:	return INT2NUM(ApiFunctionNumber(p[0], p[1], p[2], p[3], p[4]));
	case  5:	return INT2NUM(ApiFunctionNumber(p[0], p[1], p[2], p[3], p[4], p[5]));
	case  6:	return INT2NUM(ApiFunctionNumber(p[0], p[1], p[2], p[3], p[4], p[5], p[6]));
	case  7:	return INT2NUM(ApiFunctionNumber(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7]));
	case  8:	return INT2NUM(ApiFunctionNumber(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8]));
	case  9:	return INT2NUM(ApiFunctionNumber(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9]));
	case 10:	return INT2NUM(ApiFunctionNumber(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10]));
	case 11:	return INT2NUM(ApiFunctionNumber(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11]));
	case 12:	return INT2NUM(ApiFunctionNumber(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11], p[12]));
	case 13:	return INT2NUM(ApiFunctionNumber(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11], p[12], p[13]));
	case 14:	return INT2NUM(ApiFunctionNumber(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11], p[12], p[13], p[14]));
	case 15:	return INT2NUM(ApiFunctionNumber(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]));
	}
	break;
    case _T_POINTER:
	ApiFunctionPointer = (ApiPointer *) ApiFunction;
	switch (nimport) {
	case  0:	return rb_str_new2((char *)ApiFunctionPointer(p[0]));
	case  1:	return rb_str_new2((char *)ApiFunctionPointer(p[0], p[1]));
	case  2:	return rb_str_new2((char *)ApiFunctionPointer(p[0], p[1], p[2]));
	case  3:	return rb_str_new2((char *)ApiFunctionPointer(p[0], p[1], p[2], p[3]));
	case  4:	return rb_str_new2((char *)ApiFunctionPointer(p[0], p[1], p[2], p[3], p[4]));
	case  5:	return rb_str_new2((char *)ApiFunctionPointer(p[0], p[1], p[2], p[3], p[4], p[5]));
	case  6:	return rb_str_new2((char *)ApiFunctionPointer(p[0], p[1], p[2], p[3], p[4], p[5], p[6]));
	case  7:	return rb_str_new2((char *)ApiFunctionPointer(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7]));
	case  8:	return rb_str_new2((char *)ApiFunctionPointer(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8]));
	case  9:	return rb_str_new2((char *)ApiFunctionPointer(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9]));
	case 10:	return rb_str_new2((char *)ApiFunctionPointer(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10]));
	case 11:	return rb_str_new2((char *)ApiFunctionPointer(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11]));
	case 12:	return rb_str_new2((char *)ApiFunctionPointer(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11], p[12]));
	case 13:	return rb_str_new2((char *)ApiFunctionPointer(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11], p[12], p[13]));
	case 14:	return rb_str_new2((char *)ApiFunctionPointer(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11], p[12], p[13], p[14]));
	case 15:	return rb_str_new2((char *)ApiFunctionPointer(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]));
	}
	break;
    case _T_INTEGER:
	ApiFunctionInteger = (ApiInteger *) ApiFunction;
	switch (nimport) {
	case  0:	return INT2NUM(ApiFunctionInteger(p[0]));
	case  1:	return INT2NUM(ApiFunctionInteger(p[0], p[1]));
	case  2:	return INT2NUM(ApiFunctionInteger(p[0], p[1], p[2]));
	case  3:	return INT2NUM(ApiFunctionInteger(p[0], p[1], p[2], p[3]));
	case  4:	return INT2NUM(ApiFunctionInteger(p[0], p[1], p[2], p[3], p[4]));
	case  5:	return INT2NUM(ApiFunctionInteger(p[0], p[1], p[2], p[3], p[4], p[5]));
	case  6:	return INT2NUM(ApiFunctionInteger(p[0], p[1], p[2], p[3], p[4], p[5], p[6]));
	case  7:	return INT2NUM(ApiFunctionInteger(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7]));
	case  8:	return INT2NUM(ApiFunctionInteger(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8]));
	case  9:	return INT2NUM(ApiFunctionInteger(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9]));
	case 10:	return INT2NUM(ApiFunctionInteger(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10]));
	case 11:	return INT2NUM(ApiFunctionInteger(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11]));
	case 12:	return INT2NUM(ApiFunctionInteger(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11], p[12]));
	case 13:	return INT2NUM(ApiFunctionInteger(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11], p[12], p[13]));
	case 14:	return INT2NUM(ApiFunctionInteger(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11], p[12], p[13], p[14]));
	case 15:	return INT2NUM(ApiFunctionInteger(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]));
	}
	break;
    case _T_VOID:
    default:
	ApiFunctionVoid = (ApiVoid *) ApiFunction;
	switch (nimport) {
	case  0:	ApiFunctionVoid(p[0]); break;
	case  1:	ApiFunctionVoid(p[0], p[1]); break;
	case  2:	ApiFunctionVoid(p[0], p[1], p[2]); break;
	case  3:	ApiFunctionVoid(p[0], p[1], p[2], p[3]); break;
	case  4:	ApiFunctionVoid(p[0], p[1], p[2], p[3], p[4]); break;
	case  5:	ApiFunctionVoid(p[0], p[1], p[2], p[3], p[4], p[5]); break;
	case  6:	ApiFunctionVoid(p[0], p[1], p[2], p[3], p[4], p[5], p[6]); break;
	case  7:	ApiFunctionVoid(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7]); break;
	case  8:	ApiFunctionVoid(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8]); break;
	case  9:	ApiFunctionVoid(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9]); break;
	case 10:	ApiFunctionVoid(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10]); break;
	case 11:	ApiFunctionVoid(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11]); break;
	case 12:	ApiFunctionVoid(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11], p[12]); break;
	case 13:	ApiFunctionVoid(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11], p[12], p[13]); break;
	case 14:	ApiFunctionVoid(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11], p[12], p[13], p[14]); break;
	case 15:	ApiFunctionVoid(p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); break;
	}
	return INT2NUM(0);
    }
    /* not reached */
    return Qnil;
}

void
Init_Win32API()
{
    VALUE cWin32API = rb_define_class("Win32API", rb_cObject);
    rb_define_method(cWin32API, "initialize", Win32API_initialize, 4);
    rb_define_method(cWin32API, "call", Win32API_Call, -1);
    rb_define_alias(cWin32API,  "Call", "call");
}