/*******************************************************************

Namco System 1 Video Hardware

*******************************************************************/

#include "driver.h"
#include "includes/namcos1.h"


/*
  video ram map
  0000-1fff : scroll playfield (0) : 64*64*2
  2000-3fff : scroll playfield (1) : 64*64*2
  4000-5fff : scroll playfield (2) : 64*64*2
  6000-6fff : scroll playfield (3) : 64*32*2
  7000-700f : ?
  7010-77ef : fixed playfield (4)  : 36*28*2
  77f0-77ff : ?
  7800-780f : ?
  7810-7fef : fixed playfield (5)  : 36*28*2
  7ff0-7fff : ?
*/
static UINT8 *namcos1_videoram;

/*
  paletteram map (s1ram  0x0000-0x7fff)
  0000-17ff : palette page0 : sprite
  2000-37ff : palette page1 : playfield
  4000-57ff : palette page2 : playfield (shadow)
  6000-77ff : palette page3 : work RAM

  x800-x807 : CUS116 registers (visibility window)

  so there is just 3x0x2000 RAM, plus the CUS116 internal registers.
*/
static UINT8 namcos1_cus116[0x10];

/*
  spriteram map (s1ram 0x10000-0x10fff)
  0000-07ff : work ram
  0800-0fef : sprite ram    : 0x10 * 127
  0ff0-0fff : display control registers

  1000-1fff : playfield control registers
*/
static UINT8 *namcos1_spriteram;

static UINT8 namcos1_playfield_control[0x20];

static tilemap *bg_tilemap[6];
static UINT8 *tilemap_maskdata;
static int copy_sprites;

static UINT8 drawmode_table[16];




/***************************************************************************

  Callbacks for the TileMap code

***************************************************************************/

INLINE void bg_get_info(running_machine *machine,tile_data *tileinfo,int tile_index,UINT8 *info_vram)
{
	int code;

	tile_index <<= 1;
	code = info_vram[tile_index + 1] + ((info_vram[tile_index] & 0x3f) << 8);
	SET_TILE_INFO(0,code,0,0);
	tileinfo->mask_data = &tilemap_maskdata[code << 3];
}

INLINE void fg_get_info(running_machine *machine,tile_data *tileinfo,int tile_index,UINT8 *info_vram)
{
	int code;

	tile_index <<= 1;
	code = info_vram[tile_index + 1] + ((info_vram[tile_index] & 0x3f) << 8);
	SET_TILE_INFO(0,code,0,0);
	tileinfo->mask_data = &tilemap_maskdata[code << 3];
}

static TILE_GET_INFO( bg_get_info0 ) { bg_get_info(machine,tileinfo,tile_index,&namcos1_videoram[0x0000]); }
static TILE_GET_INFO( bg_get_info1 ) { bg_get_info(machine,tileinfo,tile_index,&namcos1_videoram[0x2000]); }
static TILE_GET_INFO( bg_get_info2 ) { bg_get_info(machine,tileinfo,tile_index,&namcos1_videoram[0x4000]); }
static TILE_GET_INFO( bg_get_info3 ) { bg_get_info(machine,tileinfo,tile_index,&namcos1_videoram[0x6000]); }
static TILE_GET_INFO( fg_get_info4 ) { fg_get_info(machine,tileinfo,tile_index,&namcos1_videoram[0x7010]); }
static TILE_GET_INFO( fg_get_info5 ) { fg_get_info(machine,tileinfo,tile_index,&namcos1_videoram[0x7810]); }



/***************************************************************************

  Start the video hardware emulation.

***************************************************************************/

VIDEO_START( namcos1 )
{
	int i;

	tilemap_maskdata = (UINT8 *)memory_region(machine, "gfx1");

	/* allocate videoram */
	namcos1_videoram = auto_alloc_array(machine, UINT8, 0x8000);
	namcos1_spriteram = auto_alloc_array(machine, UINT8, 0x1000);

	/* initialize playfields */
	bg_tilemap[0] = tilemap_create(machine, bg_get_info0,tilemap_scan_rows,8,8,64,64);
	bg_tilemap[1] = tilemap_create(machine, bg_get_info1,tilemap_scan_rows,8,8,64,64);
	bg_tilemap[2] = tilemap_create(machine, bg_get_info2,tilemap_scan_rows,8,8,64,64);
	bg_tilemap[3] = tilemap_create(machine, bg_get_info3,tilemap_scan_rows,8,8,64,32);
	bg_tilemap[4] = tilemap_create(machine, fg_get_info4,tilemap_scan_rows,8,8,36,28);
	bg_tilemap[5] = tilemap_create(machine, fg_get_info5,tilemap_scan_rows,8,8,36,28);

	tilemap_set_scrolldx(bg_tilemap[4],73,512-73);
	tilemap_set_scrolldx(bg_tilemap[5],73,512-73);
	tilemap_set_scrolldy(bg_tilemap[4],0x10,0x110);
	tilemap_set_scrolldy(bg_tilemap[5],0x10,0x110);

	/* register videoram to the save state system (post-allocation) */
	state_save_register_global_pointer(machine, namcos1_videoram, 0x8000);
	state_save_register_global_array(machine, namcos1_cus116);
	state_save_register_global_pointer(machine, namcos1_spriteram, 0x1000);
	state_save_register_global_array(machine, namcos1_playfield_control);

	/* set table for sprite color == 0x7f */
	for (i = 0;i < 15;i++)
		drawmode_table[i] = DRAWMODE_SHADOW;
	drawmode_table[15] = DRAWMODE_NONE;

	/* clear paletteram */
	memset(namcos1_paletteram, 0, 0x8000);
	memset(namcos1_cus116, 0, 0x10);
	for (i = 0; i < 0x2000; i++)
		palette_set_color(machine, i, MAKE_RGB(0, 0, 0));

	/* all palette entries are not affected by shadow sprites... */
	for (i = 0;i < 0x2000;i++)
		machine->shadow_table[i] = i;
	/* ... except for tilemap colors */
	for (i = 0x0800;i < 0x1000;i++)
		machine->shadow_table[i] = i + 0x0800;

	spriteram = &namcos1_spriteram[0x800];

	memset(namcos1_playfield_control, 0, sizeof(namcos1_playfield_control));
	copy_sprites = 0;
}



/***************************************************************************

  Memory handlers

***************************************************************************/

READ8_HANDLER( namcos1_videoram_r )
{
	return namcos1_videoram[offset];
}

WRITE8_HANDLER( namcos1_videoram_w )
{
	namcos1_videoram[offset] = data;
	if (offset < 0x7000)
	{   /* background 0-3 */
		int layer = offset >> 13;
		int num = (offset & 0x1fff) >> 1;
		tilemap_mark_tile_dirty(bg_tilemap[layer],num);
	}
	else
	{   /* foreground 4-5 */
		int layer = (offset >> 11 & 1) + 4;
		int num = ((offset & 0x7ff) - 0x10) >> 1;
		if (num >= 0 && num < 0x3f0)
			tilemap_mark_tile_dirty(bg_tilemap[layer],num);
	}
}


WRITE8_HANDLER( namcos1_paletteram_w )
{
	if (namcos1_paletteram[offset] == data)
		return;

	if ((offset & 0x1800) != 0x1800)
	{
		int r,g,b;
		int color = ((offset & 0x6000) >> 2) | (offset & 0x7ff);

		namcos1_paletteram[offset] = data;

		offset &= ~0x1800;
		r = namcos1_paletteram[offset];
		g = namcos1_paletteram[offset + 0x0800];
		b = namcos1_paletteram[offset + 0x1000];
		palette_set_color(space->machine,color,MAKE_RGB(r,g,b));
	}
	else
	{
		int i, j;

		namcos1_cus116[offset & 0x0f] = data;

		for (i = 0x1800; i < 0x8000; i += 0x2000)
		{
			offset = (offset & 0x0f) | i;

			for (j = 0; j < 0x80; j++, offset += 0x10)
				namcos1_paletteram[offset] = data;
		}
	}
}




READ8_HANDLER( namcos1_spriteram_r )
{
	/* 0000-07ff work ram */
	/* 0800-0fff sprite ram */
	if (offset < 0x1000)
		return namcos1_spriteram[offset];
	/* 1xxx playfield control ram */
	else
		return namcos1_playfield_control[offset & 0x1f];
}

WRITE8_HANDLER( namcos1_spriteram_w )
{
	/* 0000-07ff work ram */
	/* 0800-0fff sprite ram */
	if (offset < 0x1000)
	{
		namcos1_spriteram[offset] = data;

		/* a write to this offset tells the sprite chip to buffer the sprite list */
		if (offset == 0x0ff2)
			copy_sprites = 1;
	}
	/* 1xxx playfield control ram */
	else
		namcos1_playfield_control[offset & 0x1f] = data;
}



/***************************************************************************

  Display refresh

***************************************************************************/

/*
sprite format:

0-3  scratchpad RAM
4-9  CPU writes here, hardware copies from here to 10-15
10   xx------  X size (16, 8, 32, 4)
10   --x-----  X flip
10   ---xx---  X offset inside 32x32 tile
10   -----xxx  tile bank
11   xxxxxxxx  tile number
12   xxxxxxx-  color
12   -------x  X position MSB
13   xxxxxxxx  X position
14   xxx-----  priority
14   ---xx---  Y offset inside 32x32 tile
14   -----xx-  Y size (16, 8, 32, 4)
14   -------x  Y flip
15   xxxxxxxx  Y position
*/

static void draw_sprites(running_machine *machine, bitmap_t *bitmap, const rectangle *cliprect)
{
	const UINT8 *source = &spriteram[0x0800-0x20];	/* the last is NOT a sprite */
	const UINT8 *finish = &spriteram[0];
	gfx_element *gfx = machine->gfx[1];

	int sprite_xoffs = spriteram[0x07f5] + ((spriteram[0x07f4] & 1) << 8);
	int sprite_yoffs = spriteram[0x07f7];

	while (source >= finish)
	{
		static const int sprite_size[4] = { 16, 8, 32, 4 };
		int attr1 = source[10];
		int attr2 = source[14];
		int color = source[12];
		int flipx = (attr1 & 0x20) >> 5;
		int flipy = (attr2 & 0x01);
		int sizex = sprite_size[(attr1 & 0xc0) >> 6];
		int sizey = sprite_size[(attr2 & 0x06) >> 1];
		int tx = (attr1 & 0x18) & (~(sizex-1));
		int ty = (attr2 & 0x18) & (~(sizey-1));
		int sx = source[13] + ((color & 0x01) << 8);
		int sy = -source[15] - sizey;
		int sprite = source[11];
		int sprite_bank = attr1 & 7;
		int priority = (source[14] & 0xe0) >> 5;
		int pri_mask = (0xff << (priority + 1)) & 0xff;

		sprite += sprite_bank * 256;
		color = color >> 1;

		sx += sprite_xoffs;
		sy -= sprite_yoffs;

		if (flip_screen_get(machine))
		{
			sx = -sx - sizex;
			sy = -sy - sizey;
			flipx ^= 1;
			flipy ^= 1;
		}

		sy++;	/* sprites are buffered and delayed by one scanline */

		gfx_element_set_source_clip(gfx, tx, sizex, ty, sizey);
		if (color != 0x7f)
			pdrawgfx_transpen( bitmap, cliprect, gfx,
					sprite,
					color,
					flipx,flipy,
					sx & 0x1ff,
					((sy + 16) & 0xff) - 16,
					machine->priority_bitmap, pri_mask,
					0xf);
		else
			pdrawgfx_transtable( bitmap, cliprect, gfx,
					sprite,
					color,
					flipx,flipy,
					sx & 0x1ff,
					((sy + 16) & 0xff) - 16,
					machine->priority_bitmap, pri_mask,
					drawmode_table, machine->shadow_table);

		source -= 0x10;
	}
}



VIDEO_UPDATE( namcos1 )
{
	int i, j, scrollx, scrolly, priority;
	rectangle new_clip = *cliprect;

	/* flip screen is embedded in the sprite control registers */
	/* can't use flip_screen_set(screen->machine, ) because the visible area is asymmetrical */
	flip_screen_set_no_update(screen->machine, spriteram[0x07f6] & 1);
	tilemap_set_flip_all(screen->machine,flip_screen_get(screen->machine) ? (TILEMAP_FLIPY | TILEMAP_FLIPX) : 0);


	/* background color */
	bitmap_fill(bitmap, cliprect, get_black_pen(screen->machine));

	/* berabohm uses asymmetrical visibility windows to iris on the character */
	i = ((namcos1_cus116[0] << 8) | namcos1_cus116[1]) - 1;			// min x
	if (new_clip.min_x < i) new_clip.min_x = i;
	i = ((namcos1_cus116[2] << 8) | namcos1_cus116[3]) - 1 - 1;		// max x
	if (new_clip.max_x > i) new_clip.max_x = i;
	i = ((namcos1_cus116[4] << 8) | namcos1_cus116[5]) - 0x11;		// min y
	if (new_clip.min_y < i) new_clip.min_y = i;
	i = ((namcos1_cus116[6] << 8) | namcos1_cus116[7]) - 0x11 - 1;	// max y
	if (new_clip.max_y > i) new_clip.max_y = i;

	if (new_clip.max_x < new_clip.min_x || new_clip.max_y < new_clip.min_y)
		return 0;


	/* set palette base */
	for (i = 0;i < 6;i++)
		tilemap_set_palette_offset(bg_tilemap[i],(namcos1_playfield_control[i + 24] & 7) * 256);

	for (i = 0;i < 4;i++)
	{
		static const int disp_x[] = { 25, 27, 28, 29 };

		j = i << 2;
		scrollx = ( namcos1_playfield_control[j+1] + (namcos1_playfield_control[j+0]<<8) ) - disp_x[i];
		scrolly = ( namcos1_playfield_control[j+3] + (namcos1_playfield_control[j+2]<<8) ) + 8;

		if (flip_screen_get(screen->machine))
		{
			scrollx = -scrollx;
			scrolly = -scrolly;
		}

		tilemap_set_scrollx(bg_tilemap[i],0,scrollx);
		tilemap_set_scrolly(bg_tilemap[i],0,scrolly);
	}


	bitmap_fill(screen->machine->priority_bitmap, &new_clip, 0);

	/* bit 0-2 priority */
	/* bit 3   disable  */
	for (priority = 0; priority < 8;priority++)
	{
		for (i = 0;i < 6;i++)
		{
			if (namcos1_playfield_control[16 + i] == priority)
				tilemap_draw_primask(bitmap,&new_clip,bg_tilemap[i],0,priority,0);
		}
	}

	draw_sprites(screen->machine, bitmap, &new_clip);
	return 0;
}


VIDEO_EOF( namcos1 )
{
	if (copy_sprites)
	{
		int i,j;

		for (i = 0;i < 0x800;i += 16)
		{
			for (j = 10;j < 16;j++)
				spriteram[i+j] = spriteram[i+j - 6];
		}

		copy_sprites = 0;
	}
}
