/*
   ds81 - Nintendo DS ZX81 emulator.

   Copyright (C) 2006  Ian Cowburn <ianc@noddybox.co.uk>
   
   This program 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
   of the License, or (at your option) any later version.
   
   This program 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 this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  
   $Id$
*/

#include <nds.h>
#include <stdio.h>
#include <stdarg.h>
#include <string.h>

#include "framebuffer.h"

/* ---------------------------------------- STATIC DATA
*/
#define WIDTH	256
#define SCAN	128
#define HEIGHT	192

static uint16	*buff;
static uint16	*pal;

static uint8	font[]=
{
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x08, 0x08, 0x08, 0x08, 0x00, 0x08, 0x00,
    0x00, 0x24, 0x24, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x24, 0x7e, 0x24, 0x24, 0x7e, 0x24, 0x00,
    0x00, 0x10, 0x7c, 0x14, 0x7c, 0x50, 0x7c, 0x10,
    0x00, 0x46, 0x26, 0x10, 0x08, 0x64, 0x62, 0x00,
    0x00, 0x08, 0x14, 0x08, 0x54, 0x22, 0x5c, 0x00,
    0x00, 0x10, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x20, 0x10, 0x10, 0x10, 0x10, 0x20, 0x00,
    0x00, 0x04, 0x08, 0x08, 0x08, 0x08, 0x04, 0x00,
    0x00, 0x00, 0x28, 0x10, 0x7c, 0x10, 0x28, 0x00,
    0x00, 0x00, 0x10, 0x10, 0x7c, 0x10, 0x10, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x10, 0x10, 0x08,
    0x00, 0x00, 0x00, 0x00, 0x7c, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x18, 0x18, 0x00,
    0x00, 0x00, 0x40, 0x20, 0x10, 0x08, 0x04, 0x00,
    0x00, 0x3c, 0x62, 0x52, 0x4a, 0x46, 0x3c, 0x00,
    0x00, 0x18, 0x14, 0x10, 0x10, 0x10, 0x7c, 0x00,
    0x00, 0x3c, 0x42, 0x40, 0x3c, 0x02, 0x7e, 0x00,
    0x00, 0x3c, 0x42, 0x30, 0x40, 0x42, 0x3c, 0x00,
    0x00, 0x10, 0x18, 0x14, 0x12, 0x7e, 0x10, 0x00,
    0x00, 0x7e, 0x02, 0x3e, 0x40, 0x42, 0x3c, 0x00,
    0x00, 0x3c, 0x02, 0x3e, 0x42, 0x42, 0x3c, 0x00,
    0x00, 0x7e, 0x40, 0x20, 0x10, 0x08, 0x08, 0x00,
    0x00, 0x3c, 0x42, 0x3c, 0x42, 0x42, 0x3c, 0x00,
    0x00, 0x3c, 0x42, 0x42, 0x7c, 0x40, 0x3c, 0x00,
    0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x08, 0x00,
    0x00, 0x00, 0x08, 0x00, 0x00, 0x08, 0x08, 0x04,
    0x00, 0x00, 0x20, 0x10, 0x08, 0x10, 0x20, 0x00,
    0x00, 0x00, 0x00, 0x7c, 0x00, 0x7c, 0x00, 0x00,
    0x00, 0x00, 0x08, 0x10, 0x20, 0x10, 0x08, 0x00,
    0x00, 0x3c, 0x42, 0x20, 0x10, 0x00, 0x10, 0x00,
    0x00, 0x3c, 0x52, 0x6a, 0x7a, 0x02, 0x3c, 0x00,
    0x00, 0x3c, 0x42, 0x42, 0x7e, 0x42, 0x42, 0x00,
    0x00, 0x3e, 0x42, 0x3e, 0x42, 0x42, 0x3e, 0x00,
    0x00, 0x3c, 0x42, 0x02, 0x02, 0x42, 0x3c, 0x00,
    0x00, 0x1e, 0x22, 0x42, 0x42, 0x22, 0x1e, 0x00,
    0x00, 0x7e, 0x02, 0x3e, 0x02, 0x02, 0x7e, 0x00,
    0x00, 0x7e, 0x02, 0x3e, 0x02, 0x02, 0x02, 0x00,
    0x00, 0x3c, 0x42, 0x02, 0x72, 0x42, 0x3c, 0x00,
    0x00, 0x42, 0x42, 0x7e, 0x42, 0x42, 0x42, 0x00,
    0x00, 0x7c, 0x10, 0x10, 0x10, 0x10, 0x7c, 0x00,
    0x00, 0x40, 0x40, 0x40, 0x42, 0x42, 0x3c, 0x00,
    0x00, 0x22, 0x12, 0x0e, 0x12, 0x22, 0x42, 0x00,
    0x00, 0x02, 0x02, 0x02, 0x02, 0x02, 0x7e, 0x00,
    0x00, 0x42, 0x66, 0x5a, 0x42, 0x42, 0x42, 0x00,
    0x00, 0x42, 0x46, 0x4a, 0x52, 0x62, 0x42, 0x00,
    0x00, 0x3c, 0x42, 0x42, 0x42, 0x42, 0x3c, 0x00,
    0x00, 0x3e, 0x42, 0x42, 0x3e, 0x02, 0x02, 0x00,
    0x00, 0x3c, 0x42, 0x42, 0x4a, 0x52, 0x3c, 0x00,
    0x00, 0x3e, 0x42, 0x42, 0x3e, 0x22, 0x42, 0x00,
    0x00, 0x3c, 0x02, 0x3c, 0x40, 0x42, 0x3c, 0x00,
    0x00, 0x7f, 0x08, 0x08, 0x08, 0x08, 0x08, 0x00,
    0x00, 0x42, 0x42, 0x42, 0x42, 0x42, 0x3c, 0x00,
    0x00, 0x42, 0x42, 0x42, 0x42, 0x24, 0x18, 0x00,
    0x00, 0x42, 0x42, 0x42, 0x42, 0x5a, 0x24, 0x00,
    0x00, 0x42, 0x24, 0x18, 0x18, 0x24, 0x42, 0x00,
    0x00, 0x41, 0x22, 0x14, 0x08, 0x08, 0x08, 0x00,
    0x00, 0x7e, 0x20, 0x10, 0x08, 0x04, 0x7e, 0x00,
    0x00, 0x70, 0x10, 0x10, 0x10, 0x10, 0x70, 0x00,
    0x00, 0x00, 0x02, 0x04, 0x08, 0x10, 0x20, 0x00,
    0x00, 0x0e, 0x08, 0x08, 0x08, 0x08, 0x0e, 0x00,
    0x00, 0x08, 0x1c, 0x2a, 0x08, 0x08, 0x08, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff,
    0x00, 0x38, 0x44, 0x1e, 0x04, 0x04, 0x7e, 0x00,
    0x00, 0x00, 0x1c, 0x20, 0x3c, 0x22, 0x3c, 0x00,
    0x00, 0x04, 0x04, 0x3c, 0x44, 0x44, 0x3c, 0x00,
    0x00, 0x00, 0x38, 0x04, 0x04, 0x04, 0x38, 0x00,
    0x00, 0x20, 0x20, 0x3c, 0x22, 0x22, 0x3c, 0x00,
    0x00, 0x00, 0x1c, 0x22, 0x1e, 0x02, 0x3c, 0x00,
    0x00, 0x30, 0x08, 0x18, 0x08, 0x08, 0x08, 0x00,
    0x00, 0x00, 0x3c, 0x22, 0x22, 0x3c, 0x20, 0x1c,
    0x00, 0x02, 0x02, 0x1e, 0x22, 0x22, 0x22, 0x00,
    0x00, 0x08, 0x00, 0x0c, 0x08, 0x08, 0x1c, 0x00,
    0x00, 0x20, 0x00, 0x20, 0x20, 0x20, 0x24, 0x18,
    0x00, 0x04, 0x14, 0x0c, 0x0c, 0x14, 0x24, 0x00,
    0x00, 0x08, 0x08, 0x08, 0x08, 0x08, 0x30, 0x00,
    0x00, 0x00, 0x16, 0x2a, 0x2a, 0x2a, 0x2a, 0x00,
    0x00, 0x00, 0x1e, 0x22, 0x22, 0x22, 0x22, 0x00,
    0x00, 0x00, 0x1c, 0x22, 0x22, 0x22, 0x1c, 0x00,
    0x00, 0x00, 0x1e, 0x22, 0x22, 0x1e, 0x02, 0x02,
    0x00, 0x00, 0x3c, 0x22, 0x22, 0x3c, 0x20, 0x60,
    0x00, 0x00, 0x38, 0x04, 0x04, 0x04, 0x04, 0x00,
    0x00, 0x00, 0x1c, 0x02, 0x1c, 0x20, 0x1e, 0x00,
    0x00, 0x08, 0x1c, 0x08, 0x08, 0x08, 0x30, 0x00,
    0x00, 0x00, 0x22, 0x22, 0x22, 0x22, 0x1c, 0x00,
    0x00, 0x00, 0x22, 0x22, 0x14, 0x14, 0x08, 0x00,
    0x00, 0x00, 0x22, 0x2a, 0x2a, 0x2a, 0x14, 0x00,
    0x00, 0x00, 0x22, 0x14, 0x08, 0x14, 0x22, 0x00,
    0x00, 0x00, 0x22, 0x22, 0x22, 0x3c, 0x20, 0x1c,
    0x00, 0x00, 0x3e, 0x10, 0x08, 0x04, 0x3e, 0x00,
    0x00, 0x70, 0x10, 0x0c, 0x10, 0x10, 0x70, 0x00,
    0x00, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x00,
    0x00, 0x0e, 0x08, 0x30, 0x08, 0x08, 0x0e, 0x00,
    0x00, 0x28, 0x14, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x3c, 0x42, 0x99, 0x85, 0x85, 0x99, 0x42, 0x3c
};


/* ---------------------------------------- PRIVATE INTERFACES
*/
static inline void Plot(int x, int y, int col)
{
    uint16 *base;
    uint16 cur;
    int odd;

    if (col == -1)
    	return;

    odd = x&1;
    x /= 2;

    base = buff+x+y*SCAN;
    cur = *base;

    if (odd)
    {
    	cur = (cur & 0xff) | (col<<8);
    }
    else
    {
    	cur = (cur & 0xff00) | col;
    }

    *base = cur;
}


/* ---------------------------------------- PUBLIC INTERFACES
*/
void FB_Init(uint16 *vram, uint16 *palette)
{
    buff = vram;
    pal = palette;

    pal[COL_BLACK] = RGB15(0,0,0);
    pal[COL_WHITE] = RGB15(31,31,31);
    pal[COL_RED] = RGB15(31,0,0);
    pal[COL_GREEN] = RGB15(0,31,0);
    pal[COL_BLUE] = RGB15(0,0,31);
    pal[COL_GUISELECT] = RGB15(8,8,31);
    pal[COL_GREY] = RGB15(15,15,15);
    pal[COL_LIGHTGREY] = RGB15(22,22,22);
    pal[COL_DARKGREY] = RGB15(8,8,8);
    pal[COL_YELLOW] = RGB15(31,31,0);
}


uint16 *FB_VRAM(void)
{
    return buff;
}


uint16 *FB_PALETTE(void)
{
    return pal;
}


void FB_LoadASCIITiles(uint16 *tiles)
{
    uint8 *src;
    int c;
    int row;
    int val;
    int mask;

    src = font;

    for(c = 32; c < 127; c++)
    {
	for(row = 0; row < 8; row++)
	{
	    for(mask = 1; mask < 0xff; mask<<=1)
	    {
		if (*src & mask)
		{
		    val = COL_WHITE;
		}
		else
		{
		    val = 0;
		}

		mask <<= 1;

		if (*src & mask)
		{
		    val |= COL_WHITE << 8;
		}

		*tiles++ = val;
	    }

	src++;
	}
    }
}


void FB_Print(const char *text, int x, int y, FB_Colour colour, FB_Colour paper)
{
    int cx,cy;
    int ch;

    while(*text)
    {
	ch=((*text)-32)*8;

	for(cy=0;cy<8;cy++)
	{
	    for(cx=0;cx<8;cx++)
	    {
		if (font[ch]&(1<<cx))
		{
		    Plot(x+cx, y+cy, colour);
		}
		else
		{
		    Plot(x+cx, y+cy, paper);
		}
	    }

	    ch++;
	}

	x+=8;
	text++;
    }
}


void FB_Centre(const char *text, int y, FB_Colour colour, FB_Colour paper)
{
    FB_Print(text,WIDTH/2-strlen(text)*4,y,colour,paper);
}


void FB_printf(int x, int y, FB_Colour colour, FB_Colour paper,
	       const char *format, ...)
{
    char buff[80];
    va_list va;

    va_start(va,format);
    vsnprintf(buff,sizeof buff,format,va);
    va_end(va);

    FB_Print(buff,x,y,colour,paper);
}


void FB_HLine(int x1, int x2, int y, FB_Colour colour)
{
    uint16 *line;

    line=buff+y*WIDTH+x1;

    while(x1<=x2)
    {
    	Plot(x1++,y,colour);
    }
}


void FB_VLine(int x, int y1, int y2, FB_Colour colour)
{
    while(y1<=y2)
    {
	Plot(x,y1++,colour);
    }
}


void FB_Box(int x, int y, int w, int h, FB_Colour colour)
{
    FB_HLine(x,x+w-1,y,colour);
    FB_HLine(x,x+w-1,y+h-1,colour);
    FB_VLine(x,y,y+h-1,colour);
    FB_VLine(x+w-1,y,y+h-1,colour);
}


void FB_FillBox(int x, int y, int w, int h, FB_Colour colour)
{
    while(h--)
    {
    	FB_HLine(x,x+w-1,y++,colour);
    }
}


void FB_Clear(void)
{
    uint16 *p;
    int f;

    f=WIDTH*HEIGHT/2;
    p=buff;

    while(f--)
    {
    	*p++=0;
    }
}


void FB_Blit(sImage *img, int x, int y, int offset)
{
    uint16 *dest;
    uint16 *row;
    uint8 *src;
    uint16 pix;
    int hww;
    int ht;
    int f;

    x /= 2;

    ht = img->height;
    hww = img->width / 2;
    dest = buff+x+y*SCAN;
    src = img->image.data8;

    for(f=0;f<16;f++)
    {
    	pal[offset+f] = img->palette[f];
    }

    while(ht--)
    {
    	row = dest;

    	for(f=0;f<hww;f++)
	{
	    pix = *src++ + offset;
	    pix |= (*src++ + offset) << 8;

	    *row++ = pix;
	}

	dest += SCAN;
    }
}