/*
 * werr
 *  Just like the old one, only nicer.
 *
 * v. 1.00 (8 Aug 1993)
 *
 * © 1993-1998 Straylight
 */

/*----- Licensing note ----------------------------------------------------*
 *
 * This file is part of Straylight's Steel library.
 *
 * Steel is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * Steel is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Steel.  If not, write to the Free Software Foundation,
 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#include "werr.h"
#include "dbox.h"
#include "template.h"
#include "nopoll.h"
#include "bbc.h"
#include "wimp.h"
#include "wimpt.h"
#include "win.h"
#include "msgs.h"
#include "kernel.h"
#include "swiv.h"
#include "swis.h"
#include "exception.h"
#include "calltrace.h"
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <stdio.h>

#define werr__TITLE 0
#define werr__OK 3
#define werr__CANCEL 6
#define werr__ERROR 4
#define werr__BACKTRACE 7

static dbox werr__errorBox;
static BOOL werr__initialised;

/*
 * void werr_bleepy(void)
 *
 * Use
 *  Bleeps if and only if the appropriate WimpFlags bit is right for
 *  bleeping.
 */

void werr_bleepy(void)
{
  int bleepy=_kernel_osbyte(161,197,0);
  if (bleepy>0)
  {
    if ((bleepy&4096)==0)
      bbc_vdu(7);
  }
}

/*
 * void werr_init(void)
 *
 * Use
 *  Sets up the werr system ready for action.
 */

void werr_init(void)
{
  char *title=template_syshandle("error")->title.indirecttext.buffer;
  if (!win_anyWindows())
  {
    werr(FALSE,msgs_lookup("werrSEM:Could not initialise."));
    exit(0);
  }
  sprintf(title,"Error from %s",wimpt_programname());
  werr__errorBox=dbox_create("error");
  werr__initialised=TRUE;
}

/*
 * wimp_icon *werr__idef(wimp_wind *w,wimp_i i)
 *
 * Use
 *  Vaguely similar to the dbox version, only different.  Returns a pointer
 *  to the icon, at any rate.
 *
 * Parameters
 *  wimp_wind *w == the window definition.
 *  wimp_i i == the icon number
 *
 * Returns
 *  Pointer to the icon definition.
 */

static wimp_icon *werr__idef(wimp_wind *w,wimp_i i)
{
  return ((wimp_icon *)(w+1)+i);
}

/*
 * int werr__wimpBox(char *string,int buttons)
 *
 * Use
 *  Displays a WIMP error box to show the specified message
 *
 * Parameters
 *  char *string == the error string to display
 *  int buttons == the number of buttons to display
 */

static int werr__wimpBox(char *string,int buttons)
{
  os_error err;
  static BOOL threaded;
  int f;

  /* --- If we crashed in here before, abort damned quick --- */

  if (threaded)
  {
    _swi(Wimp_CommandWindow,_in(0),"Unrecoverable error");
    fprintf(stderr,
            "%s has suffered a fatal error and must quit.",
            wimpt_programname());
    abort();
  }

  /* --- Display the error message --- */

  threaded=TRUE;
  strcpy(err.errmess,string);
  err.errnum=1;    /* Stop new WindowManglers thinking this is serious :-/ */
  if (buttons==1)
    f=wimp_EOK;
  else
    f=wimp_EOK | wimp_ECANCEL;
  f=_swi(Wimp_ReportError,_inr(0,2)+_return(1),&err,f,wimpt_programname());
  threaded=FALSE;

  return (f==2 ? 0 : 1);
}

/*
 * int werr__reportError(int buttons,char *error,va_list ap)
 *
 * Use
 *  Error reporting primitive.  Called by all both the old and new werr()s.
 *
 * Parameters
 *  int buttons == how many buttons we need (1 or 2)
 *  char *error == a printf() type format string for the error text
 *  va_list ap == the variable arg list to use.
 *
 * Returns
 *  1 if OK clicked, 0 if Cancel clicked.
 */

static int werr__reportError(int buttons,char *error,va_list ap)
{
  wimp_wind *wind;
  wimp_icon *ok;
  wimp_icon *cancel;
  wimp_icon *backtrace=(wimp_icon *)(-80);
  int cancelButt=-1;
  int backButt=-1;
  int clicked;
  char errString[256];
  BOOL hasBacktrace;

  /* --- Set up the dialogue box --- */

  vsprintf(errString,error,ap);
  if (werr__initialised==FALSE)
    return (werr__wimpBox(errString,buttons));

  /* --- Find all the definitions we need --- */

  werr__initialised=FALSE;               /* Use the WIMP box if this fails */
  wind=template_syshandle("error");
  hasBacktrace=(wind->nicons>=werr__BACKTRACE);
  ok=werr__idef(wind,werr__OK);
  cancel=werr__idef(wind,werr__CANCEL);
  if (hasBacktrace)
    backtrace=werr__idef(wind,werr__BACKTRACE);
  dbox_delete(werr__errorBox);

  /* --- Zap any unwanted buttons --- */

  if (buttons>=2)
  {
    cancel->flags&=~(1<<23);
    cancelButt=werr__CANCEL;
  }
  else
    cancel->flags|=(1<<23);

  if (hasBacktrace)
  {
    if (buttons>=3)
    {
      backtrace->flags&=~(1<<23);
      backButt=werr__BACKTRACE;
    }
    else
      backtrace->flags|=(1<<23);
  }

  /* --- Display the error box on the screen --- */

  werr__errorBox=dbox_create("error");
  if (!werr__errorBox)
    return (werr__wimpBox(errString,buttons));
  if (!dbox_hasTitle(werr__errorBox))
    dbox_setEmbeddedTitle(werr__errorBox,werr__TITLE,FALSE);
  dbox_setfield(werr__errorBox,werr__ERROR,"%s",errString);

  /* --- Display backtraces for as long we're asked to --- */

  werr_bleepy();
  do
  {
    clicked=nopoll_doDbox(werr__errorBox,
                          nopoll_CENTRE,
                          werr__OK,
                          cancelButt,
                          backButt);
    if (clicked==nopoll_OTHER)
      _calltrace();
  }
  while (clicked==nopoll_OTHER);

  /* --- Return the result to the user --- */

  werr__initialised=TRUE;                /* Use fancy box for next error   */
  return (clicked==nopoll_OK);
}

/*
 * void werr(int fatal,char *error,...)
 *
 * Use
 *  Compatibility with the old werr segment mainly.  If the error is fatal,
 *  a STEEL exception is generated, which eventually gets round to the
 *  error box handlers and dumps back out to top level.
 *
 * Parameters
 *  int fatal == 1 if the error is fatal, or 0 otherwise.
 *  char *error == printf()-type format string.
 */

void werr(int fatal,char *error,...)
{
  va_list ap;
  va_start(ap,error);
  if (fatal==0)
  {
    werr__reportError(1,error,ap);
    va_end(ap);
  }
  else
  {
    char buffer[256];
    vsprintf(buffer,error,ap);
    va_end(ap);
    exception_generate("%s",buffer);
  }
}

/*
 * int werr_error(int buttons,char *error,...)
 *
 * Use
 *  Reports an error.  You can have two buttons, OK and Cancel if you really
 *  want, now.
 *
 * Parameters
 *  int buttons == 1 for 1 button, 2 for 2 buttons, or anything else for an
 *    unpredictable result.
 *  char *error == printf()-like format string.
 *
 * Returns
 *  1 for OK, 0 for cancel.
 */

int werr_error(int buttons,char *error,...)
{
  va_list ap;
  int clicked;
  va_start(ap,error);
  clicked=werr__reportError(buttons,error,ap);
  va_end(ap);
  return (clicked);
}