#include "driver.h"
#include "video/konamiic.h"

static int layer_colorbase[2];
static int rockrage_vreg;


PALETTE_INIT( rockrage )
{
	int i;

	/* allocate the colortable */
	machine->colortable = colortable_alloc(machine, 0x40);

	/* sprites */
	for (i = 0x20; i < 0x40; i++)
		colortable_entry_set_value(machine->colortable, i, i);

	/* characters */
	for (i = 0x40; i < 0x140; i++)
	{
		UINT8 ctabentry;

		ctabentry = (color_prom[(i - 0x40) + 0x000] & 0x0f) | 0x00;
		colortable_entry_set_value(machine->colortable, i + 0x000, ctabentry);

		ctabentry = (color_prom[(i - 0x40) + 0x100] & 0x0f) | 0x10;
		colortable_entry_set_value(machine->colortable, i + 0x100, ctabentry);
	}
}


static void set_pens(colortable_t *colortable)
{
	int i;

	for (i = 0x00; i < 0x80; i += 2)
	{
		UINT16 data = paletteram[i] | (paletteram[i | 1] << 8);

		rgb_t color = MAKE_RGB(pal5bit(data >> 0), pal5bit(data >> 5), pal5bit(data >> 10));

		colortable_palette_set_color(colortable, i >> 1, color);
	}
}


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

  Callback for the K007342

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

static void tile_callback(int layer, int bank, int *code, int *color, int *flags)
{
	if (layer == 1)
		*code |= ((*color & 0x40) << 2) | ((bank & 0x01) << 9);
	else
		*code |= ((*color & 0x40) << 2) | ((bank & 0x03) << 10) | ((rockrage_vreg & 0x04) << 7) | ((rockrage_vreg & 0x08) << 9);
	*color = layer_colorbase[layer] + (*color & 0x0f);
}

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

  Callback for the K007420

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

static void sprite_callback(int *code,int *color)
{
	*code |= ((*color & 0x40) << 2) | ((*color & 0x80) << 1)*((rockrage_vreg & 0x03) << 1);
	*code = (*code << 2) | ((*color & 0x30) >> 4);
	*color = 0;
}


WRITE8_HANDLER( rockrage_vreg_w ){
	/* bits 4-7: unused */
	/* bit 3: bit 4 of bank # (layer 0) */
	/* bit 2: bit 1 of bank # (layer 0) */
	/* bits 0-1: sprite bank select */

	if ((data & 0x0c) != (rockrage_vreg & 0x0c))
		tilemap_mark_all_tiles_dirty_all(space->machine);

	rockrage_vreg = data;
}

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

    Start the video hardware emulation.

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

VIDEO_START( rockrage )
{
	layer_colorbase[0] = 0x00;
	layer_colorbase[1] = 0x10;

	K007342_vh_start(machine,0,tile_callback);
	K007420_vh_start(machine,1,sprite_callback);

	K007420_set_banklimit(0x3ff); // bladestl and battlnts may also need this
}


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

  Screen Refresh

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

VIDEO_UPDATE( rockrage )
{
	set_pens(screen->machine->colortable);

	K007342_tilemap_update();

	K007342_tilemap_draw(bitmap,cliprect, 0, TILEMAP_DRAW_OPAQUE ,0);
	K007420_sprites_draw(bitmap,cliprect );
	K007342_tilemap_draw(bitmap,cliprect, 0, 1 | TILEMAP_DRAW_OPAQUE ,0);
	K007342_tilemap_draw(bitmap,cliprect, 1, 0 ,0);
	K007342_tilemap_draw(bitmap,cliprect, 1, 1 ,0);
	return 0;
}
