/* limit.c: layout/dimentioning and drawing routines for limits. */

/*  This file is part of asciiTeX.

    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; either version 2 of the License.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; see the file COPYING.  If not, write to
      The Free Software Foundation, Inc.
      59 Temple Place, Suite 330
      Boston, MA 02111 USA
      
    
    Authors:
    Original program (eqascii): Przemek Borys
    Fork by: Bart Pieters
       
*************************************************************************/

#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include "parsedef.h"
#include "utils.h"
#include "asciiTeX_struct.h"
#include "dim.h"
#include "draw.h"

int
dimLimit(char *found, char **Gpos, Tdim * Our, struct Tgraph *graph)
/*
The dimXxx routines all have the forllowing arguments:
found		--	Pointer to a sting containing the remaining part of the equation
Gpos		--	Pointer to a string which will contain the part of the equation 
			relevant to the current parent with flags to indicate which drawing 
			routines to use.
Our		--	dimention of the parent
graph		--	The parent
The routines returns the number of characters it used of the found vector.
*/
{
#define gpos (*Gpos)
#define our (*Our)
	char           *start,
	               *end,
	               *tmp;
	Tdim            out;

	*gpos = 1;		/* See parsedef.h for the keyword
				 * definitions */
	gpos++;
	*gpos = (char) LIMIT;
	gpos++;
	*gpos = 0;

	start = strchr(found, '{');
	if (!start)
	{
		SyntaxError("Usage: \\limit{X}\n\tProduces a limit\n");
		return 0;
	}
	end = findClosingBrace(start + 1);
	if (end - start < 2)
	{
		SyntaxError("Usage: \\limit{X}\n\tProduces a limit\n\te.g \\lim{x \\to \\infty}\n");
		return 0;
	}

	*end = 0;
	tmp = strdup(start + 1);
	*end = '}';
	out = dim(tmp, newChild(graph));
	free(tmp);

	if (start - found - 6 > 0)
		SyntaxWarning("Warning: Spurious characters ignored in \\limit\n");

	out.baseline = out.y;	/* expressison under limit */
	out.y++;		/* add the line under for the limit text */

	if (out.x > 3)
		our.x += out.x + 1;
	else
		our.x += 4;

	if (our.baseline < out.baseline)
	{
		our.y += (out.baseline - our.baseline);
		our.baseline = out.baseline;
	}
	if (our.y - our.baseline < (out.y - out.baseline))
	{
		/*
		 * our.baseline++; 
		 */
		our.y = (out.y - out.baseline) + our.baseline;
	}
	return end - (found);
#undef gpos
#undef our
}

void
drawLimit(int *Kid, int *Curx, int *Cury, char ***screen,
	  struct Tgraph *graph)
/*
The drawXxx routines all have the forllowing arguments:
Kid		--	Ineger index of the current child
Curx		--	Current x position in the 2D character field
Cury		--	Current y position in the 2D character field
screen		--	pointer to the 2D character field
graph		--	The parent
*/
{
#define kid (*Kid)
#define curx (*Curx)
#define cury (*Cury)
	int             width = graph->down[kid]->dim.x;
	if (width < 3)
		width = 3;
	drawInternal(screen, graph->down[kid], curx, cury + 1);
	(*screen)[cury][curx + (width - 1) / 2 - 1] = 'l';
	(*screen)[cury][curx + (width - 1) / 2] = 'i';
	(*screen)[cury][curx + (width - 1) / 2 + 1] = 'm';
	curx += width + 1;

	kid++;
}