/*
 * intro.c
 *
 * FRACTINT intro screen (authors & credits)
 *
 *
 */

#include <stdio.h>
#include <time.h>
#ifndef XFRACT
#include <dos.h>
#endif

#include "fractint.h"
#include "helpdefs.h"
#include "prototyp.h"

/* stuff from fractint */

extern int  lookatmouse;
extern long timer_start;
extern int  helpmode;
extern SEGTYPE  extraseg;


#ifdef XFRACT
extern int slowdisplay;
#endif


void intro_overlay(void) { }


void intro(void)
   {
   int	     toprow, botrow, i, j, delaymax;
   char      oldchar;
   int	     authors[100];		/* this should be enough for awhile */
   char far *credits;
   char far *screen_text;
   int	     oldlookatmouse;
   int	     oldhelpmode;

   ENTER_OVLY(OVLY_INTRO);

   timer_start -= clock_ticks();		/* "time out" during help */
   oldlookatmouse = lookatmouse;
   oldhelpmode = helpmode;
   lookatmouse = 0;			/* de-activate full mouse checking */

   screen_text = MK_FP(extraseg, 0);

   i = 32767 + read_help_topic(INTRO_AUTHORS, 0, 32767, screen_text);
   screen_text[i++] = '\0';
   credits = screen_text + i;
   i = 32767 + read_help_topic(INTRO_CREDITS, 0, 32767, credits);
   credits[i++] = '\0';

   j = 0;
   authors[j] = 0;		/* find the start of each credit-line */
   for (i = 0; credits[i] != 0; i++)
      if (credits[i] == 10)
	 authors[++j] = i+1;
   authors[j+1] = i;

   helptitle();
   toprow = 8;
#ifndef XFRACT
   botrow = 21;
#else
   botrow = 20;
   putstringcenter(21,0,80,C_TITLE,
   "Unix/X port of fractint by Ken Shirriff [shirriff@sprite.Berkeley.EDU]");
#endif
   putstringcenter(1,0,80,C_TITLE, "Press ENTER for main menu, F1 for help.");
   putstring(2,0,C_CONTRIB,screen_text);
   setattr(2,0,C_AUTHDIV1,80);
   setattr(7,0,C_AUTHDIV1,80);
   setattr(22,0,C_AUTHDIV2,80);
   setattr(3,0,C_PRIMARY,320);
   setattr(23,0,C_TITLE_LOW,160);
   for (i = 3; i < 7; ++i)
      setattr(i,20,C_CONTRIB,60);
   setattr(toprow,0,C_CONTRIB,14*80);
   i = botrow - toprow;
   srand(clock_ticks());
   j = rand15()%(j-(botrow-toprow)); /* first to use */
   i = j+botrow-toprow; /* last to use */
   oldchar = credits[authors[i+1]];
   credits[authors[i+1]] = 0;
   putstring(toprow,0,C_CONTRIB,credits+authors[j]);
   credits[authors[i+1]] = oldchar;
   delaymax = 10;
   movecursor(25,80); /* turn it off */
   helpmode = HELPMENU;
   while (! keypressed())
      {
#ifdef XFRACT
      if (slowdisplay) delaymax *= 15;
#endif
      for (j = 0; j < delaymax && !(keypressed()); j++)
	 delay(100);
      if (keypressed() == 32)
	 {	/* spacebar pauses */
	 getakey();
#ifndef XFRACT
         while (!keypressed()) ;
#else
         waitkeypressed(0);
#endif
	 if (keypressed() == 32)
	    getakey();
	 }
      delaymax = 15;
      scrollup(toprow, botrow);
      i++;
      if (credits[authors[i]] == 0)
	 i = 0;
      oldchar = credits[authors[i+1]];
      credits[authors[i+1]] = 0;
      putstring(botrow,0,C_CONTRIB,&credits[authors[i]]);
      setattr(botrow,0,C_CONTRIB,80);
      credits[authors[i+1]] = oldchar;
      movecursor(25,80); /* turn it off */
      }

   lookatmouse = oldlookatmouse;		/* restore the mouse-checking */
   helpmode = oldhelpmode;
   EXIT_OVLY;
   return ;
   }