/*
 * Svga.c - a Driver for Linux SVGALib in MasterGear
 *
 * Heavily derived from code by Marat Fayzullin, and useless 
 * without the MasterGear sources.
 */

#if( defined(LINUX) && defined(SVGA) )

/* Standard and SVGALib includes */

#include <stdio.h>
#include <stdlib.h>
#include <sys/signal.h>
#include <vga.h>
#include <vgakeyboard.h>

/* Private includes */

#include "SMS.h"

#ifdef SOUND
#include "DSP.h"
#endif

/* Sound related stuff */
#ifdef SOUND
int UseSound = 0;
int SndSwitch = 0x0F;
int SndVolume = 200;
#endif

/* SVGALib variables */

char* ScreenMem = NULL;

/* Miscellaneous variables/functions */

#define WIDTH 320 
#define HEIGHT 200

int Black = 0;

char* Title = "MasterGear for SVGALib";

byte *XBuf;
byte XPal[16], SPal[16];

int SaveCPU = 1;

void OnBreak(int Arg){ vga_setmode(TEXT); keyboard_close; CPURunning=0; }

void PutImage(int X, int Y, int W, int H)
{
/* Hmm... This code requires a Linear Framebuffer. As I don't manually 
 * initialise a linear framebuffer, that means that this code depends on a 
 * 320x200 video mode... I do it this way for speed. 
 */
 byte* dest, *source;
 int i, xcent, ycent;
 xcent = (WIDTH-W)/2;
 ycent = (HEIGHT-H)/2;

 dest = ScreenMem + ycent * WIDTH;
 source = XBuf + Y * WIDTH;
 
 for( i = 0; i < (H-1); i++ )
  {
   memcpy(dest + xcent, source + X, W);
   dest += WIDTH;
   source += WIDTH;
  }
 /* And there you have it - a fast and buggy update routine */
}

/* SetColor - Sets a color from the pre-allocated table */

void SetColor(byte N, byte R, byte G, byte B)
{
 byte* P;
 
 if( N>15 )
  { 
   N -= 16;
   P = SPal;
  }
 else
   P = XPal;
 P[N] = ((R&0xC0)>>2)|((G&0xC0)>>4)|((B&0xC0)>>6);
}

/* TrashMachine - Uninitialise everything */
void TrashMachine(void)
{
 if( Verbose ) printf("Shutting down...\n");
 
 free(XBuf);
 keyboard_close();
 vga_setmode(TEXT);

#ifdef SOUND
 TrashSound();
#endif 
}

/* InitMachine - Starts up all the Unix/SVGA related stuff */
int InitMachine(void)
{
 int i, j;

 if( Verbose ) 
   printf("Initialising Unix/SVGA driver:\n Allocating buffers...\n");
 
 XBuf = (byte*) malloc(sizeof(byte) * WIDTH * HEIGHT);
 if( !XBuf ) 
  { 
   if( Verbose )
     printf("FAILED\n");
   return (0); 
  }

 if( Verbose )
   printf("OK\n Initing sound...\n");
 
#ifdef SOUND
 InitSound(UseSound,Verbose);
 SetChannels(SndVolume,SndSwitch);
 SetSound(3,SND_NOISE);
#endif SOUND
 
 signal(SIGHUP,OnBreak);signal(SIGINT,OnBreak);
 signal(SIGQUIT,OnBreak);signal(SIGTERM,OnBreak);
 
 vga_init();
 vga_setmode(G320x200x256);

 ScreenMem = vga_getgraphmem();
 
 if( Verbose ) printf("OK\n Allocating colors...\n");
 for( j = 0; j < 64; j++ )
  {
   vga_setpalette(j, (j & 0x3F), (j << 2) & 0x3F, (j << 4) & 0x3F);
  }
 
 keyboard_init();
 keyboard_translatekeys(TRANSLATE_CURSORKEYS | TRANSLATE_DIAGONAL);
 
 return(1);
}

/* Josticks - Handles input. Due to differences between SVGAlib and X, this
 * may be a bit bonkers. You have been warned. Due to SVGAlib, and my 
 * laziness, only a select few keys are supported. But anyway, the key 
 * mappings I have dropped are nasty, horrid ones. So don't worry.
 */

int Joysticks(void)
{
 static int JS = 0x0000;
 static byte N = 0;
 char* keys;
  
 if( keyboard_update() == 0 )
   return JS;
 
 JS = 0;
 
 keys = keyboard_getstate();
 
#define KEY(__a) keys[SCANCODE_##__a]
 
 if( KEY(ESCAPE) || KEY(F12) )
   CPURunning = 0;
#ifdef DEBUG
 if( KEY(F1) )
   Trace = !Trace;
 if( KEY(F2) )
  {
   int J;
   printf("***** SprTab = %04Xh *****\n",SprTab-VRAM);
   for(J=0;J<64;J++)
     printf("SPRITE#%02d: %d,%d  %02Xh  %02Xh\n",
	    J,SprX(J),SprY(J),SprP(J),SprA(J));
  }
#endif
#ifdef SOUND
 if( KEY(1) )
   SetChannels(SndVolume, SndSwitch ^= 0x01);
 if( KEY(2) )
   SetChannels(SndVolume, SndSwitch ^= 0x02);
 if( KEY(3) )
   SetChannels(SndVolume, SndSwitch ^= 0x04);
 if( KEY(4) )
   SetChannels(SndVolume, SndSwitch ^= 0x08);
 if( KEY(0) )
   SetChannels(SndVolume, SndSwitch = (SndSwitch ? 0x00 : 0x0F));
 if( KEY(MINUS) || KEY(KEYPADMINUS) )
  {
   if(SndVolume>0) SndVolume-=10;
   SetChannels(SndVolume,SndSwitch);
  }
 if( KEY(EQUAL) || KEY(KEYPADPLUS) )
  {
   if(SndVolume<250) SndVolume+=10;
   SetChannels(SndVolume,SndSwitch);
  }
#endif
 if( KEY(LEFTCONTROL) )
   JS|=N? 0x0800:0x0020;
 if( KEY(LEFTALT) || KEY(SPACE) )
   JS|=N? 0x0400:0x0010;
 if( KEY(ENTER) )
   JS |= 0x2000;
 if( KEY(TAB) )
   JS |= 0x1000;
 if( KEY(CURSORDOWN) )
   JS |= N ? 0x0080 : 0x0002;
 if( KEY(CURSORUP) )
   JS |= N ? 0x0040 : 0x0001;
 if( KEY(CURSORLEFT) )
   JS |= N ? 0x0100 : 0x0004;
 if( KEY(CURSORRIGHT) )
   JS |= N ? 0x0200 : 0x0008;
 if( KEY(BACKSPACE) )
   JS |= 0x10000;
 if( KEY(CAPSLOCK) )
  { JS = 0x0000; N = 1; }
 
 return JS;
}


#include "Common.h"

#endif