/* @(#) Function which read a mask from a file.
 * @(#) Result is written in the structure IMASK or DMASK depending on whether
 * @(#) the input mask is integer or double.  The structure of the mask is 
 * @(#) given in mask.h
 * @(#)  The mask coefficients can be either int (INTMASK) 
 * @(#) or double (DOUBLEMASK).  
 * @(#)
 *
 * Copyright: 1990, N. Dessipris.
 *
 * Author: Nicos Dessipris
 * Written on: 29/04/1991
 * Modified on: 10/8/1992, J.Cupitt
 *    -	Mask reading routines no longer fail if scale and offset are missing.
 *	Instead, they set default values of scale=1, offset=0.
 *    - Code tidied up, better error recovery.
 *    -	Bugs fixed in im_dup_*mask. No longer coredump.
 *    -	Bugs fixed in im_write_*mask. Now work for non-square matricies.
 *    -	im_copy_*mask_matrix, im_copy_matrix_*mask added: copy VIPS mask 
 *	structures into Numerical Recipies in C style matricies and vice
 *	versa. Both structures should have been built before copy attempted.
 *	See im_create_*mask, im_*mat_alloc. The matrix should be indexed by 0 
 *	to size-1.
 * 9/7/93 JC
 *    - some ANSIfication and tidies
 *    -	im_free_*mask() now return zero, so they can be used as close
 *	callbacks.
 * 7/10/94 JC
 *    - new IM_NEW(), IM_ARRAY() macros added
 * 27/4/95 JC
 *    -	oops! forgot to init IM_ARRAY() memory to zero
 * 7/8/96 JC
 *    - im_scale_dmask rewritten
 * 7/5/98 JC
 *    - im_read_*mask() rewritten, now more robust
 *    - im_write_*mask() rewritten
 *    - new functions im_write_*mask_name()
 * 28/7/99 JC
 *    -	im_create_imaskv(), im_create_dmaskv() make masks and init from
 *	varargs
 *    - tabs allowed as column separators
 * 9/2/05
 *    - "," allowed as column separator ... helps CSV read
 * 31/5/06
 *    - use g_ascii_strtod() and friends
 * 2006-09-08 tcv
 *    - add im_norm_dmask()
 */

/*

    This file is part of VIPS.
    
    VIPS is free software; you can redistribute it and/or modify
    it under the terms of the GNU Lesser General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    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 Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 */

/*

    These files are distributed with VIPS - http://www.vips.ecs.soton.ac.uk

 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif /*HAVE_CONFIG_H*/
#include <vips/intl.h>

#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <math.h>

#include <vips/vips.h>

#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif /*WITH_DMALLOC*/

/* Size of line buffer for reading.
 */
#define IM_MAX_LINE (4096)

/* Free mask structure and any attached arrays. Return zero, so we can use
 * these functions as close callbacks.
 */
int
im_free_imask( INTMASK *m )
{	
  if( ! m )
    return 0;

	if( m->coeff )
		im_free( m->coeff );
	if( m->filename )
		im_free( m->filename );
	im_free( m );

	return( 0 );
}

int
im_free_dmask( DOUBLEMASK *m )
{	
  if( ! m )
    return 0;

	if( m->coeff )
		im_free( m->coeff );
	if( m->filename )
		im_free( m->filename );
	im_free( m );

	return( 0 );
}

/* Create structures.
 */
INTMASK *
im_create_imask( const char *filename, int xs, int ys )
{	
	INTMASK *m;
	int size = xs * ys;

	/* Check args.
	 */
	if( xs <= 0 || ys <= 0 || filename == NULL ) { 
		im_error( "im_create_imask", "%s", _( "bad arguments" ) ); 
		return( NULL );
	}

	/* Allocate and initialise structure.
	 */
	if( !(m = IM_NEW( NULL, INTMASK )) ) 
		return( NULL );
	m->coeff = NULL;
	m->filename = NULL;
	m->scale = 1;
	m->offset = 0;
	m->xsize = 0;
	m->ysize = 0;

	if( !(m->coeff = IM_ARRAY( NULL, size, int )) ) {
		im_free_imask( m );
		return( NULL );
	}
	(void) memset( (char *) m->coeff, 0, size * sizeof( int ) );
	if( !(m->filename = im_strdup( NULL, filename )) ) {
		im_free_imask( m );
		return( NULL );
	}
	m->xsize = xs; m->ysize = ys;

	return( m );
}

INTMASK *
im_create_imaskv( const char *filename, int xs, int ys, ... )
{	
	va_list ap;

	INTMASK *m;
	int i;

	if( !(m = im_create_imask( filename, xs, ys )) )
		return( NULL );

	va_start( ap, ys );
	for( i = 0; i < xs * ys; i++ )
		m->coeff[i] = va_arg( ap, int );
	va_end( ap );

	return( m );
}

DOUBLEMASK *
im_create_dmask( const char *filename, int xs, int ys )
{	
	DOUBLEMASK *m;
	int size = xs * ys;

	/* Check args.
	 */
	if( xs <= 0 || ys <= 0 || filename == NULL ) { 
		im_error( "im_create_dmask", "%s", _( "bad arguments" ) ); 
		return( NULL );
	}

	/* Allocate and initialise structure.
	 */
	if( !(m = IM_NEW( NULL, DOUBLEMASK )) ) 
		return( NULL );
	m->coeff = NULL;
	m->filename = NULL;
	m->scale = 1.0;
	m->offset = 0.0;
	m->xsize = 0;
	m->ysize = 0;

	if( !(m->coeff = IM_ARRAY( NULL, size, double )) ) {
		im_free_dmask( m );
		return( NULL );
	}
	(void) memset( (char *) m->coeff, 0, size * sizeof( double ) );
	if( !(m->filename = im_strdup( NULL, filename )) ) {
		im_free_dmask( m );
		return( NULL );
	}
	m->xsize = xs; m->ysize = ys;

	return( m );
}

DOUBLEMASK *
im_create_dmaskv( const char *filename, int xs, int ys, ... )
{	
	va_list ap;

	DOUBLEMASK *m;
	int i;

	if( !(m = im_create_dmask( filename, xs, ys )) )
		return( NULL );

	va_start( ap, ys );
	for( i = 0; i < xs * ys; i++ )
		m->coeff[i] = va_arg( ap, double );
	va_end( ap );

	return( m );
}

/* Open for read.
 */
static FILE *
open_read( const char *name )
{
	FILE *fp;

	if( !(fp = fopen( name, "r" )) ) {
		im_error( "read_mask", _( "Unable to open \"%s\" for input" ),
			name );
		return( NULL );
	}

	return( fp );
}

/* Read a line from a file! 
 */
static int
get_line( FILE *fp, char *buf )
{
	if( !fgets( buf, IM_MAX_LINE, fp ) ) {
		im_error( "read_mask", "%s", _( "unexpected EOF" ) );
		return( -1 );
	}

	return( 0 );
}

/* width, height, optional scale, optional offset.
 */
static int
read_header( FILE *fp, int *xs, int *ys, double *scale, double *offset )
{
	char buf[IM_MAX_LINE];
	char *p, *q;
	double v[4];
	int i;

	/* Read the first line: should contain size and optional 
	 * scale + offset. 
	 */
	if( get_line( fp, buf ) ) 
		return( -1 );

	/* Read as space separated doubles. \n is in the break list because
	 * our line will (usually) have a trailing \n which we want to count
	 * as whitespace.
	 */
	p = buf; 
	for( i = 0, p = buf; 
		i < 4 && (q = im_break_token( p, " \t\n" )); 
		i++, p = q ) 
		v[i] = g_ascii_strtod( p, NULL );

	if( (i != 2 && i != 4) ||
		ceil( v[0] ) != v[0] ||
		ceil( v[1] ) != v[1] ||
		v[0] <= 0 ||
		v[1] <= 0 ) {
		im_error( "read_header", 
			"%s", _( "error reading matrix header" ) );
		return( -1 );
	}
	if( i == 4 && v[2] == 0 ) {
		im_error( "read_header", 
			"%s", _( "scale should be non-zero" ) );
		return( -1 );
	}

	*xs = v[0];
	*ys = v[1];
	if( i == 2 ) {
		*scale = 1.0;
		*offset = 0.0;
	}
	else {
		*scale = v[2];
		*offset = v[3];
	}

	return( 0 );
}

/* Read matrix files.
 */
DOUBLEMASK *
im_read_dmask( const char *maskfile )
{
	FILE *fp;
	double sc, off;
	int xs, ys;
	DOUBLEMASK *m;
	int x, y, i, size;
	char buf[IM_MAX_LINE];

	if( !(fp = open_read( maskfile )) ) 
		return( NULL );

	if( read_header( fp, &xs, &ys, &sc, &off ) ) {
		fclose( fp );
		return( NULL );
	}

	if( !(m = im_create_dmask( maskfile, xs, ys )) ) {
		fclose( fp );
		return( NULL );
	}
	m->scale = sc;
	m->offset = off;
	size = xs * ys;

	for( i = 0, y = 0; y < ys; y++ ) {
		char *p;

		if( get_line( fp, buf ) ) {
			im_free_dmask( m );
			fclose( fp );
			return( NULL );
		}

		for( p = buf, x = 0; p && x < xs; 
			x++, i++, p = im_break_token( p, " \t,\";" ) ) 
			m->coeff[i] = g_ascii_strtod( p, NULL );
	}
	fclose( fp );

	return( m );
}

/* INTMASK ... read as double, check for intness.
 */
INTMASK *
im_read_imask( const char *maskfile )
{
	DOUBLEMASK *dmask;
	INTMASK *imask;
	int i;

	if( !(dmask = im_read_dmask( maskfile )) )
		return( NULL );

	if( ceil( dmask->scale ) != dmask->scale || 
		ceil( dmask->offset ) != dmask->offset ) {
		im_free_dmask( dmask );
		im_error( "im_read_imask", 
			"%s", _( "scale and offset should be int" ) );

		return( NULL );
	}

	for( i = 0; i < dmask->xsize * dmask->ysize; i++ ) 
		if( ceil( dmask->coeff[i] ) != dmask->coeff[i] ) {
			im_free_dmask( dmask );
			im_error( "im_read_imask", _( "cofficient at "
				"position (%d, %d) is not int" ), 
				i % dmask->xsize,
				i / dmask->xsize );

			return( NULL );
		}

	if( !(imask = im_create_imask( maskfile, 
		dmask->xsize, dmask->ysize )) ) {
		im_free_dmask( dmask );
		return( NULL );
	}
	imask->scale = dmask->scale;
	imask->offset = dmask->offset;
	for( i = 0; i < dmask->xsize * dmask->ysize; i++ ) 
		imask->coeff[i] = dmask->coeff[i];

	im_free_dmask( dmask );

	return( imask );
}

INTMASK *
im_scale_dmask( DOUBLEMASK *m, const char *name )
{
	const int size = m->xsize * m->ysize;

	INTMASK *out;
	double maxval, dsum; 
	int i;
	int isum;

	if( !name || m->xsize <= 0 || m->ysize <= 0 ) {
		im_error( "im_scale_dmask", "%s", _( "bad arguments" ) );
		return( NULL );
	}
	if( !(out = im_create_imask( name, m->xsize, m->ysize )) )
		return( NULL );

	/* Find mask max.
	 */
	maxval = m->coeff[0];
	for( i = 0; i < size; i++ ) 
		if( m->coeff[i] > maxval )
			maxval = m->coeff[i];

	/* Copy and scale, setting max to 100.
	 */
	for( i = 0; i < size; i++ ) 
		out->coeff[i] = IM_RINT( m->coeff[i] * 100.0 / maxval );
	out->offset = m->offset;

	/* Set the scale to match the adjustment to max.
	 */
	isum = 0;
	dsum = 0.0;
	for( i = 0; i < size; i++ ) { 
		isum += out->coeff[i]; 
		dsum += m->coeff[i];
	}

	if( dsum == m->scale )
		out->scale = isum;
	else
		out->scale = IM_RINT( m->scale * isum / dsum );

	return( out );	
}

void 
im_norm_dmask( DOUBLEMASK *mask )
{ 	
	const int n = mask->xsize * mask->ysize;
	const double scale = 1.0 / mask->scale;

	int i;

	if( 1.0 == scale && 0.0 == mask->offset )
		return;

	for( i = 0; i < n; i++ )
		mask->coeff[i] = mask->coeff[i] * scale + mask->offset;

	mask->scale = 1.0;
	mask->offset = 0.0;
}

INTMASK *
im_dup_imask( INTMASK *m, const char *name )
{	
	const int xs = m->xsize;
	const int ys = m->ysize;
	const int size = xs * ys;

	INTMASK *new;
	int i;

	if( !(new = im_create_imask( name, xs, ys )) )
		return( NULL );

        new->offset = m->offset; 
	new->scale = m->scale;

        for( i = 0; i < size; i++ )
		new->coeff[i] = m->coeff[i];

        return( new );
}

DOUBLEMASK *
im_dup_dmask( DOUBLEMASK *m, const char *name )
{	
	DOUBLEMASK *new;
	int xs = m->xsize;
	int ys = m->ysize;
	int size = xs * ys;
	int i;
	double *pnt1, *pnt2;

	if( !(new = im_create_dmask( name, xs, ys )) )
		return( NULL );

        new->offset = m->offset; 
	new->scale = m->scale;

        pnt1 = m->coeff;
        pnt2 = new->coeff;
        for( i = 0; i < size; i++ )
                *pnt2++ = *pnt1++;

        return( new );
}

/* Open for write.
 */
static FILE *
open_write( const char *name )
{
	FILE *fp;

	if( !(fp = fopen( name, "w" )) ) {
		im_error( "write_mask", _( "unable to open \"%s\" for output" ),
			name );
		return( NULL );
	}

	return( fp );
}

/* Write to file.
 */
static int 
write_line( FILE *fp, const char *fmt, ... )
{
	va_list ap;

	va_start( ap, fmt );
	if( !vfprintf( fp, fmt, ap ) ) {
		im_error( "write_mask", "%s", _( "write error, disc full?" ) );
		return( -1 );
	}
	va_end( ap );

	return( 0 );
}

static int 
write_double( FILE *fp, double d )
{
	char buf[G_ASCII_DTOSTR_BUF_SIZE];

	fprintf( fp, "%s", g_ascii_dtostr( buf, sizeof( buf ), d ) );

	return( 0 );
}

/* Write the INTMASK m into name.
 */
int 
im_write_imask_name( INTMASK *m, const char *name )
{
	FILE *fp;
	int x, y, i;

	if( !(fp = open_write( name )) )
		return( -1 );

	if( write_line( fp, "%d %d %d %d\n",
		m->xsize, m->ysize, m->scale, m->offset ) ) {
		fclose( fp ); 
		return( -1 );
	}

	for( i = 0, y = 0; y < m->ysize; y++ ) {
		for( x = 0; x < m->xsize; x++, i++ ) 
			if( write_line( fp, "%d ", m->coeff[i] ) ) {
				fclose( fp ); 
				return( -1 );
			}

		if( write_line( fp, "\n" ) ) {
			fclose( fp ); 
			return( -1 );
		}
	}
	fclose( fp );

	return( 0 );
}

/* Write the INTMASK m into m->filename
 */
int 
im_write_imask( INTMASK *m )
{
	if( !m->filename ) { 
		im_error( "im_write_imask", "%s", _( "filename not set" ) );
		return( -1 );
	}

	return( im_write_imask_name( m, m->filename ) );
}

/* Write the DOUBLEMASK m into name.
 */
int 
im_write_dmask_name( DOUBLEMASK *m, const char *name )
{
	FILE *fp;
	int x, y, i;

	if( !(fp = open_write( name )) )
		return( -1 );

	if( write_line( fp, "%d %d ", m->xsize, m->ysize ) ||
		write_double( fp, m->scale ) ||
		write_line( fp, " " ) ||
		write_double( fp, m->offset ) ||
		write_line( fp, "\n" ) ) {
		fclose( fp ); 
		return( -1 );
	}

	for( i = 0, y = 0; y < m->ysize; y++ ) {
		for( x = 0; x < m->xsize; x++, i++ ) 
			if( write_double( fp, m->coeff[i] ) ||
				write_line( fp, " " ) ) {
				fclose( fp ); 
				return( -1 );
			}

		if( write_line( fp, "\n" ) ) {
			fclose( fp ); 
			return( -1 );
		}
	}
	fclose( fp );

	return( 0 );
}

/* Write the DOUBLEMASK m into m->filename
 */
int 
im_write_dmask( DOUBLEMASK *m )
{
	if( !m->filename ) { 
		im_error( "im_write_dmask", "%s", _( "filename not set" ) );
		return( -1 );
	}

	return( im_write_dmask_name( m, m->filename ) );
}

/* Copy an imask into a matrix. Only used internally by matrix package for
 * invert.
 */
void 
im_copy_imask_matrix( INTMASK *mask, int **matrix )
{	
	int x, y;
	int *p = mask->coeff;

	for( y = 0; y < mask->ysize; y++ )
		for( x = 0; x < mask->xsize; x++ )
			matrix[x][y] = *p++;
}


/* Copy a matrix into an imask.
 */
void 
im_copy_matrix_imask( int **matrix, INTMASK *mask )
{	
	int x, y;
	int *p = mask->coeff;

	for( y = 0; y < mask->ysize; y++ )
		for( x = 0; x < mask->xsize; x++ )
			*p++ = matrix[x][y];
}

/* Copy a dmask into a matrix.
 */
void 
im_copy_dmask_matrix( DOUBLEMASK *mask, double **matrix )
{	
	int x, y;
	double *p = mask->coeff;

	for( y = 0; y < mask->ysize; y++ )
		for( x = 0; x < mask->xsize; x++ )
			matrix[x][y] = *p++;
}

/* Copy a matrix to a dmask.
 */
void 
im_copy_matrix_dmask( double **matrix, DOUBLEMASK *mask )
{	
	int x, y;
	double *p = mask->coeff;

	for( y = 0; y < mask->ysize; y++ )
		for( x = 0; x < mask->xsize; x++ )
			*p++ = matrix[x][y];
}