/*  Sarien - A Sierra AGI resource interpreter engine
 *  Copyright (C) 1999-2001 Stuart George and Claudio Matsuoka
 *  
 *  $Id: picture.c,v 1.44 2001/10/31 00:27:26 cmatsuoka Exp $
 *
 *  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; see docs/COPYING for further details.
 */

#include <stdio.h>
#include <string.h>
#include <assert.h>
#include "sarien.h"
#include "agi.h"
#include "graphics.h"
#include "rand.h"
#include "savegame.h"

#define next_byte data[foffs++]

static UINT8	*data;
static UINT32	flen;
static UINT32	foffs;

static UINT8	patCode;
static UINT8	patNum;
static UINT8	pri_on;
static UINT8	scr_on;
static UINT8	scr_colour;
static UINT8	pri_colour;


static void put_virt_pixel (int x, int y)
{
	UINT8 *p;

	if (x >= _WIDTH || y >= _HEIGHT)
		return;

	p = &game.sbuf[y * _WIDTH + x];

	if (pri_on) *p = (pri_colour << 4) | (*p & 0x0f);
	if (scr_on) *p = scr_colour | (*p & 0xf0);
}


/* For the flood fill routines */

#define STACK_SEG_SIZE 0x1000

struct point_xy {
	struct point_xy *next;
	unsigned int x, y;
};

#define MAX_STACK_SEGS 16
static unsigned int stack_num_segs;
static unsigned int stack_seg;
static unsigned int stack_ptr;

static struct point_xy *stack[MAX_STACK_SEGS];

static INLINE void _PUSH (struct point_xy *c)
{
	if (stack_ptr >= STACK_SEG_SIZE) {
		/* Allocate new stack segment */

		assert (stack_num_segs < MAX_STACK_SEGS);

		if (stack_num_segs <= ++stack_seg) {
			_D ("new stack (#%d)", stack_num_segs);
			stack[stack_num_segs] = malloc (sizeof (struct point_xy)
				* STACK_SEG_SIZE);
			assert (stack[stack_num_segs] != NULL);
			stack_num_segs++;
		}
		stack_ptr = 0;
	}

	stack[stack_seg][stack_ptr].x = c->x;
	stack[stack_seg][stack_ptr].y = c->y;
	stack_ptr++;
}


static INLINE void _POP (struct point_xy *c)
{
	if (stack_ptr == 0) {
		if (stack_seg == 0) {
			c->x = c->y = 0xffff;
		} else {
			stack_seg--;
			 stack_ptr = STACK_SEG_SIZE - 1;
		}

		return;
	}

	stack_ptr--;
	c->x = stack[stack_seg][stack_ptr].x;
	c->y = stack[stack_seg][stack_ptr].y;
}


/**************************************************************************
** drawline
** Draws an AGI line.
**
** line drawing routine sent to me by joshua neal
** modified by stuart george, fixed >>2 to >>1 and some other bugs
** like x1 instead of y1, etc
**************************************************************************/
static void draw_line (int x1, int y1, int x2, int y2)
{
	int i, x, y, deltaX, deltaY, stepX, stepY, errorX, errorY, detdelta;

	/* CM: Do clipping */
#define clip(x, y) if((x)>=(y)) (x)=(y)
	clip (x1, _WIDTH-1);
	clip (x2, _WIDTH-1);
	clip (y1, _HEIGHT-1);
	clip (y2, _HEIGHT-1);

	/* Vertical line */

	if (x1 == x2) {
		if(y1 > y2) {
			y = y1;
			y1 = y2;
			y2 = y;
		}

		for ( ; y1 <= y2; y1++)
			put_virt_pixel (x1, y1);

		return;
	}

	/* Horizontal line */

	if (y1 == y2) {
		if (x1 > x2) {
			x = x1;
			x1 = x2;
			x2 = x;
		}

   		for( ; x1 <= x2; x1++)
   			put_virt_pixel (x1, y1);

		return;
	}

	y = y1;
  	x = x1;

	stepY = 1;
	deltaY = y2-y1;
	if (deltaY < 0) {
		stepY = -1;
		deltaY = -deltaY;
	}

	stepX = 1;
	deltaX = x2 - x1;
	if (deltaX < 0) {
		stepX = -1;
		deltaX = -deltaX;
	}

	if(deltaY > deltaX) {
		i=deltaY;
		detdelta=deltaY;
		errorX=deltaY/2;
		errorY=0;
	} else {
		i=deltaX;
		detdelta=deltaX;
		errorX=0;
		errorY=deltaX/2;
	}

	put_virt_pixel (x, y);

	do {
		errorY += deltaY;
		if (errorY >= detdelta) {
			errorY -= detdelta;
			y += stepY;
		}

		errorX += deltaX;
		if (errorX >= detdelta) {
			errorX -= detdelta;
			x += stepX;
		}

		put_virt_pixel(x, y);
		i--;
	} while (i > 0);

	/* put_virt_pixel (x, y); */
}

/**************************************************************************
** relativeDraw
**
** Draws short lines relative to last position.  (drawing action 0xF7)
**************************************************************************/
static void dynamic_draw_line ()
{
	int x1, y1, disp, dx, dy;

	x1 = next_byte;
	y1 = next_byte;

	put_virt_pixel (x1, y1);

	while (42) {
		if ((disp = next_byte) >= 0xf0)
			break;

		dx= ((disp & 0xf0) >> 4) & 0x0f;
		dy= (disp & 0x0f);

	      	if (dx & 0x08)
			dx = -(dx & 0x07);

	      	if (dy & 0x08)
			dy = -(dy & 0x07);

		draw_line (x1, y1, x1 + dx, y1 + dy);
		x1 += dx;
		y1 += dy;
	}
	foffs--;
}

/**************************************************************************
** absoluteLine
**
** Draws long lines to actual locations (cf. relative) (drawing action 0xF6)
**************************************************************************/
static void absolute_draw_line ()
{
	int x1, y1, x2, y2;

	x1 = next_byte;
	y1 = next_byte;
	put_virt_pixel (x1, y1);

	while (42) {
		if ((x2 = next_byte) >= 0xf0)
			break;

		if ((y2 = next_byte) >= 0xf0)
			break;

		draw_line (x1, y1, x2, y2);
		x1 = x2;
		y1 = y2;
	}
	foffs--;
}


/**************************************************************************
** okToFill
**************************************************************************/
static INLINE int is_ok_fill_here (int x, int y)
{
	unsigned int i;
	UINT8 p;

	if (!scr_on && !pri_on)
		return FALSE;

	i = y * _WIDTH + x;
	p = game.sbuf[i];

	if (!pri_on && scr_on && scr_colour != 15)
		return (p & 0x0f) == 15;

	if (pri_on && !scr_on && pri_colour != 4)
		return (p >> 4) == 4;

	return (scr_on && (p & 0x0f) == 15 && scr_colour != 15);
}

/**************************************************************************
** agiFill
**************************************************************************/
static void agiFill (int x, int y)
{
	struct point_xy c;

	c.x = x;
	c.y = y;
	_PUSH (&c);

	while (42) {
		_POP(&c);

		/* Exit if stack is empty */
		if (c.x == 0xffff || c.y == 0xffff)
			break;

		if (is_ok_fill_here (c.x, c.y)) {
			put_virt_pixel (c.x, c.y);
			if (c.x > 0 && is_ok_fill_here (c.x - 1, c.y)) {
				c.x--; _PUSH (&c); c.x++;
    			}
			if (c.x < _WIDTH - 1 && is_ok_fill_here (c.x + 1, c.y)) {
				c.x++; _PUSH (&c); c.x--;
 			}
			if (c.y < _HEIGHT - 1 && is_ok_fill_here (c.x, c.y + 1)) {
				c.y++; _PUSH (&c); c.y--;
    			}
			if (c.y > 0 && is_ok_fill_here (c.x, c.y - 1)) {
				c.y--; _PUSH (&c); c.y++;
    			}
		}
	}

	stack_ptr = 0;
	stack_seg = 0;
}

/**************************************************************************
** xCorner
**
** Draws an xCorner  (drawing action 0xF5)
**************************************************************************/
static void x_corner ()
{
	int x1, x2, y1, y2;

	x1 = next_byte;
	y1 = next_byte;
   	put_virt_pixel (x1, y1);

	while (42) {
		x2=next_byte;

		if (x2 >= 0xf0)
			break;

		draw_line (x1, y1, x2, y1);
		x1 = x2;
		y2 = next_byte;

		if (y2 >= 0xF0)
			break;

		draw_line (x1, y1, x1, y2);
		y1 = y2;
	}
	foffs--;
}


/**************************************************************************
** yCorner
**
** Draws an yCorner  (drawing action 0xF4)
**************************************************************************/
static void y_corner ()
{
	int x1, x2, y1, y2;

	x1 = next_byte;
	y1 = next_byte;
	put_virt_pixel (x1, y1);

	while (42) {
		y2 = next_byte;

		if (y2 >= 0xF0)
			break;

		draw_line (x1, y1, x1, y2);
		y1 = y2;
		x2 = next_byte;

		if (x2 >= 0xF0)
			break;

		draw_line (x1, y1, x2, y1);
		x1 = x2;
	}

	foffs--;
}

/**************************************************************************
** fill
**
** AGI flood fill.  (drawing action 0xF8)
**************************************************************************/
static void fill ()
{
	int x1, y1;

	while ((x1 = next_byte) < 0xF0 && (y1 = next_byte) < 0xF0)
		agiFill (x1, y1);

	foffs--;
}


#define plotPatternPoint() do {						\
	if (patCode & 0x20) {						\
		if ((splatterMap[bitPos>>3] >> (7-(bitPos&7))) & 1)	\
			put_virt_pixel(x1, y1);				\
		bitPos++;						\
		if (bitPos == 0xff)					\
			bitPos=0;					\
	} else put_virt_pixel(x1, y1);					\
} while (0)

/**************************************************************************
** plotPattern
**
** Draws pixels, circles, squares, or splatter brush patterns depending
** on the pattern code.
**************************************************************************/
void plotPattern(unsigned int x, unsigned int y)
{
	static UINT8 circles[][15] = {		/* agi circle bitmaps */
		{ 0x80 },
		{ 0xfc },
		{ 0x5f, 0xf4 },
		{ 0x66, 0xff, 0xf6, 0x60 },
		{ 0x23, 0xbf, 0xff, 0xff, 0xee, 0x20 },
		{ 0x31, 0xe7, 0x9e, 0xff, 0xff, 0xde, 0x79, 0xe3, 0x00 },
		{ 0x38, 0xf9, 0xf3, 0xef, 0xff, 0xff,
		  0xff, 0xfe, 0xf9, 0xf3, 0xe3, 0x80 },
		{ 0x18, 0x3c, 0x7e, 0x7e, 0x7e, 0xff, 0xff,
		  0xff, 0xff, 0xff, 0x7e, 0x7e, 0x7e, 0x3c, 0x18 }
	};

	static UINT8 splatterMap[32] = {	/* splatter brush bitmaps */
		0x20, 0x94, 0x02, 0x24, 0x90, 0x82, 0xa4, 0xa2,
		0x82, 0x09, 0x0a, 0x22, 0x12, 0x10, 0x42, 0x14,
		0x91, 0x4a, 0x91, 0x11, 0x08, 0x12, 0x25, 0x10,
		0x22, 0xa8, 0x14, 0x24, 0x00, 0x50, 0x24, 0x04
	};

	static UINT8 splatterStart[128] = {	/* starting bit position */
		0x00, 0x18, 0x30, 0xc4, 0xdc, 0x65, 0xeb, 0x48,
		0x60, 0xbd, 0x89, 0x05, 0x0a, 0xf4, 0x7d, 0x7d,
		0x85, 0xb0, 0x8e, 0x95, 0x1f, 0x22, 0x0d, 0xdf,
		0x2a, 0x78, 0xd5, 0x73, 0x1c, 0xb4, 0x40, 0xa1,
		0xb9, 0x3c, 0xca, 0x58, 0x92, 0x34, 0xcc, 0xce,
		0xd7, 0x42, 0x90, 0x0f, 0x8b, 0x7f, 0x32, 0xed,
		0x5c, 0x9d, 0xc8, 0x99, 0xad, 0x4e, 0x56, 0xa6,
		0xf7, 0x68, 0xb7, 0x25, 0x82, 0x37, 0x3a, 0x51,
		0x69, 0x26, 0x38, 0x52, 0x9e, 0x9a, 0x4f, 0xa7,
		0x43, 0x10, 0x80, 0xee, 0x3d, 0x59, 0x35, 0xcf,
		0x79, 0x74, 0xb5, 0xa2, 0xb1, 0x96, 0x23, 0xe0,
		0xbe, 0x05, 0xf5, 0x6e, 0x19, 0xc5, 0x66, 0x49,
		0xf0, 0xd1, 0x54, 0xa9, 0x70, 0x4b, 0xa4, 0xe2,
		0xe6, 0xe5, 0xab, 0xe4, 0xd2, 0xaa, 0x4c, 0xe3,
		0x06, 0x6f, 0xc6, 0x4a, 0xa4, 0x75, 0x97, 0xe1
	};

	SINT32 circlePos = 0;
	UINT32 x1, y1, penSize, bitPos = splatterStart[patNum];

	penSize = (patCode & 7);

	if (x < penSize)
		x = penSize-1;
	if (y < penSize)
		y = penSize;

	for (y1 = y - penSize; y1 <= y + penSize; y1++) {
		for (x1 = x-(penSize+1)/2; x1<=x+penSize/2; x1++) {
			if (patCode & 0x10) {		/* Square */
				plotPatternPoint();
			} else {			/* Circle */
				if ((circles[patCode&7][circlePos>>3] >> (7-(circlePos&7)))&1)
					plotPatternPoint();
				circlePos++;
			}
		}
	}
}

/**************************************************************************
** plotBrush
**
** Plots points and various brush patterns.
**************************************************************************/
static void plot_brush ()
{
	int x1, y1;

	while (42) {
		if (patCode & 0x20) {
			if ((patNum = next_byte) >= 0xF0)
				break;
			patNum = (patNum >> 1) & 0x7f;
		}

		if ((x1 = next_byte) >= 0xf0)
			break;

		if ((y1 = next_byte) >= 0xf0)
			break;

		plotPattern (x1, y1);
   	}

   	foffs--;
}

#ifdef USE_HIRES
#include "hirespic.c"
#endif

static void draw_picture ()
{
	UINT8 act;
	unsigned int i;
	int drawing;
#ifdef USE_HIRES
	int save_foffs;
#endif

 	patCode = 0;
 	patNum = 0;
 	pri_on = scr_on = FALSE;
 	scr_colour = 0xf;
 	pri_colour = 0x4;

	drawing = 1;

	stack[0] = calloc (sizeof (struct point_xy), STACK_SEG_SIZE);
	stack_ptr = stack_seg = 0;
	stack_num_segs = 1;

	_D (_D_WARN "Drawing picture");
	for (drawing = 1; drawing && foffs < flen; ) {

#ifdef USE_HIRES
		save_foffs = foffs;
#endif

		act = next_byte;
		switch(act) {
		case 0xf0:			/* set colour on screen */
			scr_colour = next_byte;
			scr_colour &= 0xF;	/* for v3 drawing diff */
			scr_on = TRUE;
			break;
		case 0xf1:			/* disable screen drawing */
			scr_on = FALSE;
			break;
		case 0xf2:			/* set colour on priority */
			pri_colour = next_byte;
			pri_colour &= 0xf;	/* for v3 drawing diff */
			pri_on = TRUE;
			break;
		case 0xf3:			/* disable priority screen */
			pri_on = FALSE;
			break;
		case 0xf4:			/* y-corner */
			y_corner ();
			break;
		case 0xf5:			/* x-corner */
			x_corner ();
			break;
		case 0xf6:			/* absolute draw lines */
			absolute_draw_line ();
			break;
		case 0xf7:			/* dynamic draw lines */
			dynamic_draw_line ();
			break;
		case 0xf8:			/* fill */
			fill ();
			break;
		case 0xf9:			/* set pattern */
			patCode = next_byte;
			break;
		case 0xfA:			/* plot brush */
			plot_brush ();
			break;
		case 0xFF:			/* end of pic data */
		default:
			drawing = 0;
			break;
		}

#ifdef USE_HIRES
		foffs = save_foffs;

		act = next_byte;
		switch(act) {
		case 0xf0:			/* set colour on screen */
			scr_colour = next_byte;
			scr_colour &= 0xF;	/* for v3 drawing diff */
			scr_on = TRUE;
			break;
		case 0xf1:			/* disable screen drawing */
			scr_on = FALSE;
			break;
		case 0xf2:			/* set colour on priority */
			pri_colour = next_byte;
			pri_colour &= 0xf;	/* for v3 drawing diff */
			pri_on = TRUE;
			break;
		case 0xf3:			/* disable priority screen */
			pri_on = FALSE;
			break;
		case 0xf4:			/* y-corner */
			hires_y_corner ();
			break;
		case 0xf5:			/* x-corner */
			hires_x_corner ();
			break;
		case 0xf6:			/* absolute draw lines */
			absolute_hires_line ();
			break;
		case 0xf7:			/* dynamic draw lines */
			dynamic_hires_line ();
			break;
		case 0xf8:			/* fill */
			hires_fill ();
			break;
		case 0xf9:			/* set pattern */
			patCode = next_byte;
			break;
		case 0xfA:			/* plot brush */
			plot_hires_brush ();
			break;
		case 0xFF:			/* end of pic data */
		default:
			drawing = 0;
			break;
		}
#endif
	}

	for (i = 0; i < stack_num_segs; i++)
		free (stack[i]);
}

/*
 * Public functions
 */

/**
 *
 */
UINT8* convert_v3_pic (UINT8 *data, UINT32 len)
{
	UINT8	d, old = 0, x, *in, *xdata, *out, mode = 0;
	UINT32	i, ulen;

	xdata = malloc (len + len / 2);

	out = xdata;
	in = data;

	for (i = ulen = 0; i < len; i++, ulen++) {
		d = *in++;

		*out++ = x = mode ? ((d & 0xF0) >> 4) + ((old & 0x0F) << 4) : d;

		if (x == 0xFF) {
			ulen++;
			break;
		}

		if (x == 0xf0 || x == 0xf2) {
			if (mode) {
				*out++ = d & 0x0F;
				ulen++;
			} else {
				d = *in++;
				*out++ = (d & 0xF0) >> 4;
				i++, ulen++;
			}

			mode = !mode;
		}

		old = d;
	}

	free (data);
	xdata = realloc (xdata, ulen);

	return xdata;
}

/**
 * Decode an AGI picture resource.
 * This function decodes an AGI picture resource into the correct slot
 * and draws it on the AGI screen, optionally cleaning the screen before
 * drawing.
 * @param n      AGI picture resource number
 * @param clear  clear AGI screen before drawing
 */
int decode_picture (int n, int clear)
{
	_D (_D_WARN "(%d)", n);

	patCode = 0;
	patNum = 0;
	pri_on = scr_on = FALSE;
	scr_colour = 0xF;
	pri_colour = 0x4;

	data = game.pictures[n].rdata;
	flen = game.dir_pic[n].len;
	foffs = 0;

	if (clear) {
		memset (game.sbuf, 0x4f, _WIDTH * _HEIGHT);
#ifdef USE_HIRES
		memset (game.hires, 0x4f, _WIDTH * 2 * _HEIGHT);
#endif
	}

	draw_picture ();

#ifdef USE_HIRES
	fix_hires_picture ();
#endif

	if(clear)
		clear_image_stack();
	record_image_stack_call(ADD_PIC, n, clear, 0, 0, 0, 0, 0);

	return err_OK;
}


/**
 * Unload an AGI picture resource.
 * This function unloads an AGI picture resource and deallocates
 * resource data.
 * @param n AGI picture resource number
 */
int unload_picture (int n)
{
	/* remove visual buffer & priority buffer if they exist */
	if (game.dir_pic[n].flags & RES_LOADED) {
		free (game.pictures[n].rdata);	
		game.dir_pic[n].flags &= ~RES_LOADED;
	}

	return err_OK;
}

/**
 * Show AGI picture.
 * This function copies a ``hidden'' AGI picture to the output device.
 */
void show_pic ()
{
	int i, y;
	int offset;

#ifdef USE_HIRES
	if (opt.hires) {
		show_hires_pic ();
		return;
	}
#endif

	i = 0;
	offset = game.line_min_print * CHAR_LINES;
	for (y = 0; y < _HEIGHT; y++) {
		put_pixels_a (0, y + offset, _WIDTH, &game.sbuf[i]);
		i += _WIDTH;
	}

#if 0
	/* Amiga/IIgs transitions. Too slow, and annoying after a few rooms.
	 * Also doesn't work well with console.
	 */
#define BRICK_W 4
#define BRICK_H 2
	for (i = 0; i < 20000; i++) {
		int bx = rnd (GFX_WIDTH / BRICK_W) * BRICK_W;
		int by = rnd (GFX_HEIGHT / BRICK_H) * BRICK_H;
		flush_block (bx, by, bx + BRICK_W - 1, by + BRICK_H - 1);
		do_update ();
	}
#endif

	flush_screen ();
}


/* end: picture.c */