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

  vidhrdw/apple2.c

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

#include "driver.h"
#include "vidhrdw/generic.h"
#include "includes/apple2.h"

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

static const UINT8 *a2_videoram;
static UINT32 a2_videomask;
static UINT32 old_a2;
static tilemap *text_tilemap;
static tilemap *dbltext_tilemap;
static tilemap *lores_tilemap;
static int text_videobase;
static int dbltext_videobase;
static int lores_videobase;
static int fgcolor, bgcolor, flash;
static int alt_charset_value;
static UINT16 *hires_artifact_map;
static UINT16 *dhires_artifact_map;
static UINT8 *lores_tiledata;

#define	BLACK	0
#define DKRED	1
#define	DKBLUE	2
#define PURPLE	3
#define DKGREEN	4
#define DKGRAY	5
#define	BLUE	6
#define LTBLUE	7
#define BROWN	8
#define ORANGE	9
#define	GRAY	10
#define PINK	11
#define GREEN	12
#define YELLOW	13
#define AQUA	14
#define	WHITE	15

#define ALWAYS_REFRESH			0
#define FLASH_PERIOD			TIME_IN_SEC(0.25)
#define PROFILER_VIDEOTOUCH		PROFILER_USER3

/***************************************************************************
  helpers
***************************************************************************/

INLINE UINT32 effective_a2(void)
{
	return a2 & a2_videomask;
}



static void apple2_draw_tilemap(mame_bitmap *bitmap, const rectangle *cliprect,
	int beginrow, int endrow, tilemap *tm, int raw_videobase, int *tm_videobase)
{
	rectangle new_cliprect;

	new_cliprect = *cliprect;

	if (new_cliprect.min_y < beginrow)
		new_cliprect.min_y = beginrow;
	if (new_cliprect.max_y > endrow)
		new_cliprect.max_y = endrow;
	if (new_cliprect.min_y > new_cliprect.max_y)
		return;

	if (raw_videobase != *tm_videobase)
	{
		*tm_videobase = raw_videobase;
		tilemap_mark_all_tiles_dirty(tm);
	}
	tilemap_draw(bitmap, &new_cliprect, tm, 0, 0);
}

/***************************************************************************
  text
***************************************************************************/

static void apple2_generaltext_gettileinfo(int gfxset, int videobase, int memory_offset)
{
	int character;
	int current_fgcolor = fgcolor;
	int current_bgcolor = bgcolor;
	int i;
	
	character = a2_videoram[videobase + memory_offset];

	if (effective_a2() & VAR_ALTCHARSET)
	{
		character |= alt_charset_value;
	}
	else if (flash && (character >= 0x40) && (character <= 0x7f))
	{
		i = current_fgcolor;
		current_fgcolor = current_bgcolor;
		current_bgcolor = i;
	}

	SET_TILE_INFO(
		gfxset,										/* gfx */
		character,									/* character */
		(current_fgcolor * 16) + current_bgcolor,	/* color */
		0);											/* flags */
}

static void apple2_text_gettileinfo(int memory_offset)
{
	apple2_generaltext_gettileinfo(0, text_videobase, memory_offset);
}

static void apple2_dbltext_gettileinfo(int memory_offset)
{
	apple2_generaltext_gettileinfo(1, dbltext_videobase, memory_offset);
}

static UINT32 apple2_text_getmemoryoffset(UINT32 col, UINT32 row, UINT32 num_cols, UINT32 num_rows)
{
	/* Special Apple II addressing.  Gotta love it. */
	return (((row & 0x07) << 7) | ((row & 0x18) * 5 + col));
}

static UINT32 apple2_dbltext_getmemoryoffset(UINT32 col, UINT32 row, UINT32 num_cols, UINT32 num_rows)
{
	return apple2_text_getmemoryoffset(col / 2, row, num_cols / 2, num_rows) + ((col % 2) ? 0x00000 : 0x10000);
}

static void apple2_text_draw(mame_bitmap *bitmap, const rectangle *cliprect, int page, int beginrow, int endrow)
{
	if (effective_a2() & VAR_80COL)
		apple2_draw_tilemap(bitmap, cliprect, beginrow, endrow, dbltext_tilemap, page ? 0x800 : 0x400, &dbltext_videobase);
	else
		apple2_draw_tilemap(bitmap, cliprect, beginrow, endrow, text_tilemap, page ? 0x800 : 0x400, &text_videobase);
}

void apple2_set_fgcolor(int color)
{
	if (color != fgcolor)
	{
		tilemap_mark_all_tiles_dirty(text_tilemap);
		tilemap_mark_all_tiles_dirty(dbltext_tilemap);
		fgcolor = color;
	}
}

void apple2_set_bgcolor(int color)
{
	if (color != bgcolor)
	{
		tilemap_mark_all_tiles_dirty(text_tilemap);
		tilemap_mark_all_tiles_dirty(dbltext_tilemap);
		bgcolor = color;
	}
}

int apple2_get_fgcolor(void)
{
	return fgcolor;
}

int apple2_get_bgcolor(void)
{
	return bgcolor;
}

/***************************************************************************
  low resolution graphics
***************************************************************************/

static void apple2_lores_gettileinfo(int memory_offset)
{
	static pen_t pal_data[2];
	int ch;

	tile_info.tile_number = 0;
	tile_info.pen_data = lores_tiledata;
	tile_info.pal_data = pal_data;
	tile_info.pen_usage = 0;
	tile_info.flags = 0;

	ch = a2_videoram[lores_videobase + memory_offset];
	pal_data[0] = (ch >> 0) & 0x0f;
	pal_data[1] = (ch >> 4) & 0x0f;
}

static void apple2_lores_draw(mame_bitmap *bitmap, const rectangle *cliprect, int page, int beginrow, int endrow)
{
	apple2_draw_tilemap(bitmap, cliprect, beginrow, endrow, lores_tilemap, page ? 0x800 : 0x400, &lores_videobase);
}

/***************************************************************************
  high resolution graphics
***************************************************************************/

static UINT32 apple2_hires_getmemoryoffset(UINT32 col, UINT32 row, UINT32 num_cols, UINT32 num_rows)
{
	/* Special Apple II addressing.  Gotta love it. */
	return apple2_text_getmemoryoffset(col, row / 8, num_cols, num_rows) | ((row & 7) << 10);
}

struct drawtask_params
{
	mame_bitmap *bitmap;
	const UINT8 *vram;
	int beginrow;
	int rowcount;
	int columns;
};

static void apple2_hires_draw_task(void *param, int task_num, int task_count)
{
	struct drawtask_params *dtparams;
	mame_bitmap *bitmap;
	const UINT8 *vram;
	int beginrow;
	int endrow;
	int row, col, b;
	int offset;
	int columns;
	UINT8 vram_row[82];
	UINT16 v;
	UINT16 *p;
	UINT32 w;
	UINT16 *artifact_map_ptr;

	dtparams = (struct drawtask_params *) param;

	bitmap		= dtparams->bitmap;
	vram		= dtparams->vram;
	beginrow	= dtparams->beginrow + (dtparams->rowcount * task_num     / task_count);
	endrow		= dtparams->beginrow + (dtparams->rowcount * (task_num+1) / task_count) - 1;
	columns		= dtparams->columns;

	vram_row[0] = 0;
	vram_row[columns + 1] = 0;

	assert((columns == 40) || (columns == 80));

	for (row = beginrow; row <= endrow; row++)
	{
		for (col = 0; col < 40; col++)
		{
			offset = apple2_hires_getmemoryoffset(col, row, 0, 0);

			switch(columns) {
			case 40:
				vram_row[1+col] = vram[offset];
				break;

			case 80:
				vram_row[1+(col*2)+0] = vram[offset + 0x10000];
				vram_row[1+(col*2)+1] = vram[offset + 0x00000];
				break;
			}
		}

		p = (UINT16 *) bitmap->line[row];

		for (col = 0; col < columns; col++)
		{
			w =		(((UINT32) vram_row[col+0] & 0x7f) <<  0)
				|	(((UINT32) vram_row[col+1] & 0x7f) <<  7)
				|	(((UINT32) vram_row[col+2] & 0x7f) << 14);
	
			switch(columns) {
			case 40:
				artifact_map_ptr = &hires_artifact_map[((vram_row[col+1] & 0x80) >> 7) * 16];
				for (b = 0; b < 7; b++)
				{
					v = artifact_map_ptr[((w >> (b + 7-1)) & 0x07) | (((b ^ col) & 0x01) << 3)];
					*(p++) = v;
					*(p++) = v;
				}
				break;

			case 80:
				for (b = 0; b < 7; b++)
				{
					v = dhires_artifact_map[((((w >> (b + 7-1)) & 0x0F) * 0x11) >> (((2-(col*7+b))) & 0x03)) & 0x0F];
					*(p++) = v;
				}
				break;

			default:
				assert(0);
				break;
			}
		}
	}
}

static void apple2_hires_draw(mame_bitmap *bitmap, const rectangle *cliprect, int page, int beginrow, int endrow)
{
	struct drawtask_params dtparams;

	if (beginrow < cliprect->min_y)
		beginrow = cliprect->min_y;
	if (endrow > cliprect->max_y)
		endrow = cliprect->max_y;
	if (endrow < beginrow)
		return;

	dtparams.vram = a2_videoram + (page ? 0x4000 : 0x2000);
	dtparams.bitmap = bitmap;
	dtparams.beginrow = beginrow;
	dtparams.rowcount = (endrow + 1) - beginrow;
	dtparams.columns = ((effective_a2() & (VAR_DHIRES|VAR_80COL)) == (VAR_DHIRES|VAR_80COL)) ? 80 : 40;

	osd_parallelize(apple2_hires_draw_task, &dtparams, dtparams.rowcount);
}



/***************************************************************************
  video core
***************************************************************************/

int apple2_video_start(const UINT8 *vram, size_t vram_size, UINT32 ignored_softswitches, int hires_modulo)
{
	int i, j;
	UINT16 c;
	UINT8 *apple2_font;

	static const UINT8 hires_artifact_color_table[] =
	{
		BLACK,	PURPLE,	GREEN,	WHITE,
		BLACK,	BLUE,	ORANGE,	WHITE
	};

	static const UINT8 dhires_artifact_color_table[] =
	{
		BLACK,		DKGREEN,	BROWN,	GREEN,
		DKRED,		DKGRAY,		ORANGE,	YELLOW,
		DKBLUE,		BLUE,		GRAY,	AQUA,
		PURPLE,		LTBLUE,		PINK,	WHITE
	};

	fgcolor = 15;
	bgcolor = 0;
	flash = 0;
	apple2_font = memory_region(REGION_GFX1);
	alt_charset_value = memory_region_length(REGION_GFX1) / 16;
	a2_videoram = vram;

	text_tilemap = tilemap_create(
		apple2_text_gettileinfo,
		apple2_text_getmemoryoffset,
		TILEMAP_OPAQUE,
		7*2, 8,
		40, 24);

	dbltext_tilemap = tilemap_create(
		apple2_dbltext_gettileinfo,
		apple2_dbltext_getmemoryoffset,
		TILEMAP_OPAQUE,
		7, 8,
		80, 24);

	lores_tilemap = tilemap_create(
		apple2_lores_gettileinfo,
		apple2_text_getmemoryoffset,
		TILEMAP_OPAQUE,
		14, 8,
		40, 24);

	/* 2^3 dependent pixels * 2 color sets * 2 offsets */
	hires_artifact_map = auto_malloc(sizeof(UINT16) * 8 * 2 * 2);

	/* 2^4 dependent pixels */
	dhires_artifact_map = auto_malloc(sizeof(UINT16) * 16);

	/* 14x8 */
	lores_tiledata = auto_malloc(sizeof(UINT8) * 14 * 8);

	if (!text_tilemap || !lores_tilemap || !hires_artifact_map || !dhires_artifact_map)
		return 1;
	
	/* build lores_tiledata */
	memset(lores_tiledata + 0*14, 0, 4*14);
	memset(lores_tiledata + 4*14, 1, 4*14);

	/* build hires artifact map */
	for (i = 0; i < 8; i++)
	{
		for (j = 0; j < 2; j++)
		{
			if (i & 0x02)
			{
				if ((i & 0x05) != 0)
					c = 3;
				else
					c = j ? 2 : 1;
			}
			else
			{
				if ((i & 0x05) == 0x05)
					c = j ? 1 : 2;
				else
					c = 0;
			}
			hires_artifact_map[ 0 + j*8 + i] = hires_artifact_color_table[(c + 0) % hires_modulo];
			hires_artifact_map[16 + j*8 + i] = hires_artifact_color_table[(c + 4) % hires_modulo];
		}
	}

	/* build double hires artifact map */
	for (i = 0; i < 16; i++)
	{
		dhires_artifact_map[i] = dhires_artifact_color_table[i];
	}

	memset(&old_a2, 0, sizeof(old_a2));
	text_videobase = lores_videobase = 0;
	a2_videomask = ~ignored_softswitches;
	return 0;
}



VIDEO_START( apple2 )
{
	if (apple2_video_start(mess_ram, mess_ram_size, VAR_80COL | VAR_ALTCHARSET | VAR_DHIRES, 4))
		return 1;

	/* hack to fix the colors on apple2/apple2p */
	fgcolor = 0;
	bgcolor = 15;
	return 0;
}


VIDEO_START( apple2p )
{
	if (apple2_video_start(mess_ram, mess_ram_size, VAR_80COL | VAR_ALTCHARSET | VAR_DHIRES, 8))
		return 1;

	/* hack to fix the colors on apple2/apple2p */
	fgcolor = 0;
	bgcolor = 15;
	return 0;
}


VIDEO_START( apple2e )
{
	return apple2_video_start(mess_ram, mess_ram_size, 0, 8);
}


VIDEO_UPDATE( apple2 )
{
	int page;
	int new_flash;
	UINT32 new_a2;

	new_flash = ((int) (timer_get_time() / FLASH_PERIOD)) & 1;
	if (flash != new_flash)
	{
		flash = new_flash;
		tilemap_mark_all_tiles_dirty(text_tilemap);
		tilemap_mark_all_tiles_dirty(dbltext_tilemap);
	}

	/* read out relevant softswitch variables; to see what has changed */
	new_a2 = effective_a2();
	if (new_a2 & VAR_80STORE)
		new_a2 &= ~VAR_PAGE2;
	new_a2 &= VAR_TEXT | VAR_MIXED | VAR_HIRES | VAR_DHIRES | VAR_80COL | VAR_PAGE2 | VAR_ALTCHARSET;

	if (ALWAYS_REFRESH || (new_a2 != old_a2))
	{
		old_a2 = new_a2;
		tilemap_mark_all_tiles_dirty(text_tilemap);
		tilemap_mark_all_tiles_dirty(dbltext_tilemap);
		tilemap_mark_all_tiles_dirty(lores_tilemap);
	}

	/* choose which page to use */
	page = (new_a2 & VAR_PAGE2) ? 1 : 0;

	if (effective_a2() & VAR_TEXT)
	{
		apple2_text_draw(bitmap, cliprect, page, 0, 191);
	}
	else if ((effective_a2() & VAR_HIRES) && (effective_a2() & VAR_MIXED))
	{
		apple2_hires_draw(bitmap, cliprect, page, 0, 159);
		apple2_text_draw(bitmap, cliprect, page, 160, 191);
	}
	else if (effective_a2() & VAR_HIRES)
	{
		apple2_hires_draw(bitmap, cliprect, page, 0, 191);
	}
	else if (effective_a2() & VAR_MIXED)
	{
		apple2_lores_draw(bitmap, cliprect, page, 0, 159);
		apple2_text_draw(bitmap, cliprect, page, 160, 191);
	}
	else
	{
		apple2_lores_draw(bitmap, cliprect, page, 0, 191);
	}
}

void apple2_video_touch(offs_t offset)
{
	profiler_mark(PROFILER_VIDEOTOUCH);
	if (offset >= text_videobase)
		tilemap_mark_tile_dirty(text_tilemap, offset - text_videobase);
	if (offset >= dbltext_videobase)
		tilemap_mark_tile_dirty(dbltext_tilemap, offset - dbltext_videobase);
	if (offset >= lores_videobase)
		tilemap_mark_tile_dirty(lores_tilemap, offset - text_videobase);
	profiler_mark(PROFILER_END);
}
