/*
 * Copyright (c) 2008 Martin Decky
 * Copyright (c) 2006 Ondrej Palkovsky
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup genarch
 * @{
 */
/** @file
 */

#include <genarch/fb/font-8x16.h>
#include <genarch/fb/visuals.h>
#include <genarch/fb/fb.h>
#include <console/chardev.h>
#include <console/console.h>
#include <sysinfo/sysinfo.h>
#include <mm/slab.h>
#include <align.h>
#include <panic.h>
#include <memstr.h>
#include <config.h>
#include <bitops.h>
#include <print.h>
#include <ddi/ddi.h>
#include <arch/types.h>

SPINLOCK_INITIALIZE(fb_lock);

/**< Physical memory area for fb. */
static parea_t fb_parea;

static uint8_t *fb_addr;
static uint8_t *backbuf;
static uint8_t *glyphs;

static void *bgpixel;

static unsigned int xres;
static unsigned int yres;

static unsigned int scanline;
static unsigned int glyphscanline;

static unsigned int pixelbytes;
static unsigned int glyphbytes;

static unsigned int cols;
static unsigned int rows;
static unsigned int position = 0;

#define BG_COLOR     0x000080
#define FG_COLOR     0xffff00

#define CURSOR       219

#define RED(x, bits)         ((x >> (8 + 8 + 8 - bits)) & ((1 << bits) - 1))
#define GREEN(x, bits)       ((x >> (8 + 8 - bits)) & ((1 << bits) - 1))
#define BLUE(x, bits)        ((x >> (8 - bits)) & ((1 << bits) - 1))

#define COL2X(col)           ((col) * FONT_WIDTH)
#define ROW2Y(row)           ((row) * FONT_SCANLINES)

#define X2COL(x)             ((x) / FONT_WIDTH)
#define Y2ROW(y)             ((y) / FONT_SCANLINES)

#define FB_POS(x, y)         ((y) * scanline + (x) * pixelbytes)
#define BB_POS(col, row)     ((row) * cols + (col))
#define GLYPH_POS(glyph, y)  ((glyph) * glyphbytes + (y) * glyphscanline)


static void (*rgb_conv)(void *, uint32_t);


/** ARGB 8:8:8:8 conversion
 *
 */
static void rgb_0888(void *dst, uint32_t rgb)
{
	*((uint32_t *) dst) = rgb & 0xffffff;
}


/** ABGR 8:8:8:8 conversion
 *
 */
static void bgr_0888(void *dst, uint32_t rgb)
{
	*((uint32_t *) dst)
	    = (BLUE(rgb, 8) << 16) | (GREEN(rgb, 8) << 8) | RED(rgb, 8);
}


/** BGR 8:8:8 conversion
 *
 */
static void rgb_888(void *dst, uint32_t rgb)
{
#if defined(FB_INVERT_ENDIAN)
	*((uint32_t *) dst)
	    = (BLUE(rgb, 8) << 16) | (GREEN(rgb, 8) << 8) | RED(rgb, 8)
	    | (*((uint32_t *) dst) & 0xff0000);
#else
	*((uint32_t *) dst)
	    = (rgb & 0xffffff) | (*((uint32_t *) dst) & 0xff0000);
#endif
}


/** RGB 5:5:5 conversion
 *
 */
static void rgb_555(void *dst, uint32_t rgb)
{
	*((uint16_t *) dst)
	    = (RED(rgb, 5) << 10) | (GREEN(rgb, 5) << 5) | BLUE(rgb, 5);
}


/** RGB 5:6:5 conversion
 *
 */
static void rgb_565(void *dst, uint32_t rgb)
{
	*((uint16_t *) dst)
	    = (RED(rgb, 5) << 11) | (GREEN(rgb, 6) << 5) | BLUE(rgb, 5);
}


/** RGB 3:2:3
 *
 * Even though we try 3:2:3 color scheme here, an 8-bit framebuffer
 * will most likely use a color palette. The color appearance
 * will be pretty random and depend on the default installed
 * palette. This could be fixed by supporting custom palette
 * and setting it to simulate the 8-bit truecolor.
 *
 * Currently we set the palette on the ia32 and sparc64 port.
 *
 * Note that the byte is being inverted by this function. The reason is
 * that we would like to use a color palette where the white color code
 * is 0 and the black color code is 255, as some machines (SunBlade 1500) 
 * use these codes for black and white and prevent to set codes
 * 0 and 255 to other colors.
 */
static void rgb_323(void *dst, uint32_t rgb)
{
	*((uint8_t *) dst)
	    = ~((RED(rgb, 3) << 5) | (GREEN(rgb, 2) << 3) | BLUE(rgb, 3));
}


/** Draw character at given position
 *
 */
static void draw_glyph(uint8_t glyph, unsigned int col, unsigned int row)
{
	unsigned int x = COL2X(col);
	unsigned int y = ROW2Y(row);
	unsigned int yd;
	
	backbuf[BB_POS(col, row)] = glyph;
	
	for (yd = 0; yd < FONT_SCANLINES; yd++)
		memcpy(&fb_addr[FB_POS(x, y + yd)],
		    &glyphs[GLYPH_POS(glyph, yd)], glyphscanline);
}


/** Scroll screen down by one row
 *
 *
 */
static void scroll_screen(void)
{
	unsigned int row;
	
	for (row = 0; row < rows; row++) {
		unsigned int y = ROW2Y(row);
		unsigned int yd;
		
		for (yd = 0; yd < FONT_SCANLINES; yd++) {
			unsigned int x;
			unsigned int col;
			
			for (col = 0, x = 0; col < cols; col++, x += FONT_WIDTH) {
				uint8_t glyph;
				
				if (row < rows - 1) {
					if (backbuf[BB_POS(col, row)] == backbuf[BB_POS(col, row + 1)])
						continue;
					
					glyph = backbuf[BB_POS(col, row + 1)];
				} else
					glyph = 0;
				
				memcpy(&fb_addr[FB_POS(x, y + yd)],
				    &glyphs[GLYPH_POS(glyph, yd)], glyphscanline);
			}
		}
	}
	
	memcpy(backbuf, backbuf + cols, cols * (rows - 1));
	memsetb(&backbuf[BB_POS(0, rows - 1)], cols, 0);
}


static void cursor_put(void)
{
	draw_glyph(CURSOR, position % cols, position / cols);
}


static void cursor_remove(void)
{
	draw_glyph(0, position % cols, position / cols);
}


/** Print character to screen
 *
 * Emulate basic terminal commands.
 *
 */
static void fb_putchar(chardev_t *dev, char ch)
{
	spinlock_lock(&fb_lock);
	
	switch (ch) {
	case '\n':
		cursor_remove();
		position += cols;
		position -= position % cols;
		break;
	case '\r':
		cursor_remove();
		position -= position % cols;
		break;
	case '\b':
		cursor_remove();
		if (position % cols)
			position--;
		break;
	case '\t':
		cursor_remove();
		do {
			draw_glyph((uint8_t) ' ', position % cols, position / cols);
			position++;
		} while ((position % 8) && (position < cols * rows));
		break;
	default:
		draw_glyph((uint8_t) ch, position % cols, position / cols);
		position++;
	}
	
	if (position >= cols * rows) {
		position -= cols;
		scroll_screen();
	}
	
	cursor_put();
	
	spinlock_unlock(&fb_lock);
}

static chardev_t framebuffer;
static chardev_operations_t fb_ops = {
	.write = fb_putchar,
};


/** Render glyphs
 *
 * Convert glyphs from device independent font
 * description to current visual representation.
 *
 */
static void render_glyphs(void)
{
	unsigned int glyph;
	
	for (glyph = 0; glyph < FONT_GLYPHS; glyph++) {
		unsigned int y;
		
		for (y = 0; y < FONT_SCANLINES; y++) {
			unsigned int x;
			
			for (x = 0; x < FONT_WIDTH; x++)
				rgb_conv(&glyphs[GLYPH_POS(glyph, y) + x * pixelbytes],
				    (fb_font[glyph * FONT_SCANLINES + y] & (1 << (7 - x))) ? FG_COLOR : BG_COLOR);
		}
	}
	
	rgb_conv(bgpixel, BG_COLOR);
}


/** Refresh the screen
 *
 */
void fb_redraw(void)
{
	unsigned int row;
	
	for (row = 0; row < rows; row++) {
		unsigned int y = ROW2Y(row);
		unsigned int yd;
		
		for (yd = 0; yd < FONT_SCANLINES; yd++) {
			unsigned int x;
			unsigned int col;
			
			for (col = 0, x = 0; col < cols; col++, x += FONT_WIDTH)
				memcpy(&fb_addr[FB_POS(x, y + yd)],
			    &glyphs[GLYPH_POS(backbuf[BB_POS(col, row)], yd)],
			    glyphscanline);
		}
	}
	
	if (COL2X(cols) < xres) {
		unsigned int y;
		
		for (y = 0; y < yres; y++) {
			unsigned int x;
			
			for (x = COL2X(cols); x < xres; x++)
				memcpy(&fb_addr[FB_POS(x, y)], bgpixel, pixelbytes);
		}
	}
	
	if (ROW2Y(rows) < yres) {
		unsigned int y;
		
		for (y = ROW2Y(rows); y < yres; y++) {
			unsigned int x;
			
			for (x = 0; x < xres; x++)
				memcpy(&fb_addr[FB_POS(x, y)], bgpixel, pixelbytes);
		}
	}
}


/** Initialize framebuffer as a chardev output device
 *
 * @param addr   Physical address of the framebuffer
 * @param x      Screen width in pixels
 * @param y      Screen height in pixels
 * @param scan   Bytes per one scanline
 * @param visual Color model
 *
 */
void fb_init(fb_properties_t *props)
{
	switch (props->visual) {
	case VISUAL_INDIRECT_8:
		rgb_conv = rgb_323;
		pixelbytes = 1;
		break;
	case VISUAL_RGB_5_5_5:
		rgb_conv = rgb_555;
		pixelbytes = 2;
		break;
	case VISUAL_RGB_5_6_5:
		rgb_conv = rgb_565;
		pixelbytes = 2;
		break;
	case VISUAL_RGB_8_8_8:
		rgb_conv = rgb_888;
		pixelbytes = 3;
		break;
	case VISUAL_RGB_8_8_8_0:
		rgb_conv = rgb_888;
		pixelbytes = 4;
		break;
	case VISUAL_RGB_0_8_8_8:
		rgb_conv = rgb_0888;
		pixelbytes = 4;
		break;
	case VISUAL_BGR_0_8_8_8:
		rgb_conv = bgr_0888;
		pixelbytes = 4;
		break;
	default:
		panic("Unsupported visual.\n");
	}
	
	xres = props->x;
	yres = props->y;
	scanline = props->scan;
	
	cols = xres / FONT_WIDTH;
	rows = yres / FONT_SCANLINES;
	
	glyphscanline = FONT_WIDTH * pixelbytes;
	glyphbytes = glyphscanline * FONT_SCANLINES;
	
	unsigned int fbsize = scanline * yres;
	unsigned int bbsize = cols * rows;
	unsigned int glyphsize = FONT_GLYPHS * glyphbytes;
	
	backbuf = (uint8_t *) malloc(bbsize, 0);
	if (!backbuf)
		panic("Unable to allocate backbuffer.\n");
	
	glyphs = (uint8_t *) malloc(glyphsize, 0);
	if (!glyphs)
		panic("Unable to allocate glyphs.\n");
	
	bgpixel = malloc(pixelbytes, 0);
	if (!bgpixel)
		panic("Unable to allocate background pixel.\n");
	
	memsetb(backbuf, bbsize, 0);
	memsetb(glyphs, glyphsize, 0);
	memsetb(bgpixel, pixelbytes, 0);
	
	render_glyphs();
	
	fb_addr = (uint8_t *) hw_map((uintptr_t) props->addr, fbsize);
	
	fb_parea.pbase = (uintptr_t) props->addr + props->offset;
	fb_parea.vbase = (uintptr_t) fb_addr;
	fb_parea.frames = SIZE2FRAMES(fbsize);
	fb_parea.cacheable = false;
	ddi_parea_register(&fb_parea);
	
	sysinfo_set_item_val("fb", NULL, true);
	sysinfo_set_item_val("fb.kind", NULL, 1);
	sysinfo_set_item_val("fb.width", NULL, xres);
	sysinfo_set_item_val("fb.height", NULL, yres);
	sysinfo_set_item_val("fb.scanline", NULL, scanline);
	sysinfo_set_item_val("fb.visual", NULL, props->visual);
	sysinfo_set_item_val("fb.address.physical", NULL, props->addr);
	
	fb_redraw();
	
	chardev_initialize("fb", &framebuffer, &fb_ops);
	stdout = &framebuffer;
}

/** @}
 */