/* 
Fri Aug 15 16:29:47 EDT 1997
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
    Matrix Market I/O library for ANSI C
    Roldan Pozo, NIST (pozo@nist.gov)
 
    See http://math.nist.gov/MatrixMarket for details and sample
    calling programs.
 
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
                                NOTICE

 Permission to use, copy, modify, and distribute this software and
 its documentation for any purpose and without fee is hereby granted
 provided that the above copyright notice appear in all copies and
 that both the copyright notice and this permission notice appear in
 supporting documentation.

 Neither the Author nor the Institution (National Institute of Standards
 and Technology) make any representations about the suitability of this 
 software for any purpose. This software is provided "as is" without 
 expressed or implied warranty.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
*/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <ctype.h>

#include "mmio.h"

int mm_is_valid(MM_typecode matcode)
{
    if (!mm_is_matrix(matcode)) return 0;
    if (mm_is_dense(matcode) && mm_is_pattern(matcode)) return 0;
    if (mm_is_real(matcode) && mm_is_hermitian(matcode)) return 0;
    if (mm_is_pattern(matcode) && (mm_is_hermitian(matcode) || 
                mm_is_skew(matcode))) return 0;
    return 1;
}

int mm_read_banner(FILE *f, MM_typecode *matcode)
{
    char line[MM_MAX_LINE_LENGTH];
    char banner[MM_MAX_TOKEN_LENGTH];
    char mtx[MM_MAX_TOKEN_LENGTH]; 
    char crd[MM_MAX_TOKEN_LENGTH];
    char data_type[MM_MAX_TOKEN_LENGTH];
    char storage_scheme[MM_MAX_TOKEN_LENGTH];
    char *p;


    mm_clear_typecode(matcode);  

    if (fgets(line, MM_MAX_LINE_LENGTH, f) == NULL) 
        return MM_PREMATURE_EOF;

    if (sscanf(line, "%s %s %s %s %s", banner, mtx, crd, data_type, 
        storage_scheme) != 5)
        return MM_PREMATURE_EOF;

				/* these tokens are compared to lower-case constants */
    for (p=mtx; *p!='\0'; *p=tolower(*p),p++);  /* convert to lower case */
    for (p=crd; *p!='\0'; *p=tolower(*p),p++);  
    for (p=data_type; *p!='\0'; *p=tolower(*p),p++);
    for (p=storage_scheme; *p!='\0'; *p=tolower(*p),p++);

    /* check for banner */
    if (strncmp(banner, MatrixMarketBanner, strlen(MatrixMarketBanner)) != 0)
        return MM_NO_HEADER;

    /* first field should be "mtx" */
    if (strcmp(mtx, MM_MTX_STR) != 0)
        return  MM_NOT_MTX;
    mm_set_matrix(matcode);


    /* second field describes whether this is a sparse matrix (in coordinate
            storgae) or a dense array */


    if (strcmp(crd, MM_SPARSE_STR) == 0)
        mm_set_sparse(matcode);
    else
    if (strcmp(crd, MM_DENSE_STR) == 0)
            mm_set_dense(matcode);
    else
        return MM_UNSUPPORTED_TYPE;
    

    /* third field */

    if (strcmp(data_type, MM_REAL_STR) == 0)
        mm_set_real(matcode);
    else
    if (strcmp(data_type, MM_COMPLEX_STR) == 0)
        mm_set_complex(matcode);
    else
    if (strcmp(data_type, MM_PATTERN_STR) == 0)
        mm_set_pattern(matcode);
    else
    if (strcmp(data_type, MM_INT_STR) == 0)
        mm_set_integer(matcode);
    else
        return MM_UNSUPPORTED_TYPE;
    

    /* fourth field */

    if (strcmp(storage_scheme, MM_GENERAL_STR) == 0)
        mm_set_general(matcode);
    else
    if (strcmp(storage_scheme, MM_SYMM_STR) == 0)
        mm_set_symmetric(matcode);
    else
    if (strcmp(storage_scheme, MM_HERM_STR) == 0)
        mm_set_hermitian(matcode);
    else
    if (strcmp(storage_scheme, MM_SKEW_STR) == 0)
        mm_set_skew(matcode);
    else
        return MM_UNSUPPORTED_TYPE;
        

    return 0;
}

int mm_write_mtx_crd_size(FILE *f, int M, int N, int nz)
{
    if (fprintf(f, "%d %d %d\n", M, N, nz) != 3)
        return MM_COULD_NOT_WRITE_FILE;
    else 
        return 0;
}

int mm_read_mtx_crd_size(FILE *f, int *M, int *N, int *nz )
{
    char line[MM_MAX_LINE_LENGTH];
    int num_items_read;

    /* set return null parameter values, in case we exit with errors */
    *M = *N = *nz = 0;

    /* now continue scanning until you reach the end-of-comments */
    do 
    {
        if (fgets(line,MM_MAX_LINE_LENGTH,f) == NULL) 
            return MM_PREMATURE_EOF;
    }while (line[0] == '%');

    /* line[] is either blank or has M,N, nz */
    if (sscanf(line, "%d %d %d", M, N, nz) == 3)
        return 0;
        
    else
    do
    { 
        num_items_read = fscanf(f, "%d %d %d", M, N, nz); 
        if (num_items_read == EOF) return MM_PREMATURE_EOF;
    }
    while (num_items_read != 3);

    return 0;
}


int mm_read_mtx_array_size(FILE *f, int *M, int *N)
{
    char line[MM_MAX_LINE_LENGTH];
    int num_items_read;

    /* set return null parameter values, in case we exit with errors */
    *M = *N = 0;

    /* now continue scanning until you reach the end-of-comments */
    do 
    {
        if (fgets(line,MM_MAX_LINE_LENGTH,f) == NULL) 
            return MM_PREMATURE_EOF;
    }while (line[0] == '%');

    /* line[] is either blank or has M,N, nz */
    if (sscanf(line, "%d %d", M, N) == 2)
        return 0;
        
    else /* we have a blank line */
    do
    { 
        num_items_read = fscanf(f, "%d %d", M, N); 
        if (num_items_read == EOF) return MM_PREMATURE_EOF;
    }
    while (num_items_read != 2);

    return 0;
}

int mm_write_mtx_array_size(FILE *f, int M, int N)
{
    if (fprintf(f, "%d %d\n", M, N) != 2)
        return MM_COULD_NOT_WRITE_FILE;
    else 
        return 0;
}



/*-------------------------------------------------------------------------*/

/******************************************************************/
/* use when I[], J[], and val[]J, and val[] are already allocated */
/******************************************************************/

int mm_read_mtx_crd_data(FILE *f, int M, int N, int nz, int I[], int J[],
        double val[], MM_typecode matcode)
{
    int i;
    if (mm_is_complex(matcode))
    {
        for (i=0; i<nz; i++)
            if (fscanf(f, "%d %d %lg %lg", &I[i], &J[i], &val[2*i], &val[2*i+1])
                != 4) return MM_PREMATURE_EOF;
    }
    else if (mm_is_real(matcode))
    {
        for (i=0; i<nz; i++)
        {
            if (fscanf(f, "%d %d %lg\n", &I[i], &J[i], &val[i])
                != 3) return MM_PREMATURE_EOF;

        }
    }

    else if (mm_is_pattern(matcode))
    {
        for (i=0; i<nz; i++)
            if (fscanf(f, "%d %d", &I[i], &J[i])
                != 2) return MM_PREMATURE_EOF;
    }
    else
        return MM_UNSUPPORTED_TYPE;

    return 0;
        
}

int mm_read_mtx_crd_entry(FILE *f, int *I, int *J,
        double *real, double *imag, MM_typecode matcode)
{
    if (mm_is_complex(matcode))
    {
            if (fscanf(f, "%d %d %lg %lg", I, J, real, imag)
                != 4) return MM_PREMATURE_EOF;
    }
    else if (mm_is_real(matcode))
    {
            if (fscanf(f, "%d %d %lg\n", I, J, real)
                != 3) return MM_PREMATURE_EOF;

    }

    else if (mm_is_pattern(matcode))
    {
            if (fscanf(f, "%d %d", I, J) != 2) return MM_PREMATURE_EOF;
    }
    else
        return MM_UNSUPPORTED_TYPE;

    return 0;
        
}


/************************************************************************
    mm_read_mtx_crd()  fills M, N, nz, array of values, and return
                        type code, e.g. 'MCRS'

                        if matrix is complex, values[] is of size 2*nz,
                            (nz pairs of real/imaginary values)
************************************************************************/

int mm_read_mtx_crd(char *fname, int *M, int *N, int *nz, int **I, int **J, 
        double **val, MM_typecode *matcode)
{
    int ret_code;
    FILE *f;

    if (strcmp(fname, "stdin") == 0) f=stdin;
    else
    if ((f = fopen(fname, "r")) == NULL)
        return MM_COULD_NOT_READ_FILE;


    if ((ret_code = mm_read_banner(f, matcode)) != 0)
        return ret_code;

    if (!(mm_is_valid(*matcode) && mm_is_sparse(*matcode) && 
            mm_is_matrix(*matcode)))
        return MM_UNSUPPORTED_TYPE;

    if ((ret_code = mm_read_mtx_crd_size(f, M, N, nz)) != 0)
        return ret_code;


    *I = (int *)  malloc(*nz * sizeof(int));
    *J = (int *)  malloc(*nz * sizeof(int));
    *val = NULL;

    if (mm_is_complex(*matcode))
    {
        *val = (double *) malloc(*nz * 2 * sizeof(double));
        ret_code = mm_read_mtx_crd_data(f, *M, *N, *nz, *I, *J, *val, 
                *matcode);
        if (ret_code != 0) return ret_code;
    }
    else if (mm_is_real(*matcode))
    {
        *val = (double *) malloc(*nz * sizeof(double));
        ret_code = mm_read_mtx_crd_data(f, *M, *N, *nz, *I, *J, *val, 
                *matcode);
        if (ret_code != 0) return ret_code;
    }

    else if (mm_is_pattern(*matcode))
    {
        ret_code = mm_read_mtx_crd_data(f, *M, *N, *nz, *I, *J, *val, 
                *matcode);
        if (ret_code != 0) return ret_code;
    }

    if (f != stdin) fclose(f);
    return 0;
}

void mm_write_banner(FILE *f, MM_typecode matcode)
{
    char *str = mm_typecode_to_str(matcode);

    fprintf(f, "%s ", MatrixMarketBanner);
    fprintf(f, "%s\n", str);
    free(str);
}

int mm_write_mtx_crd(char fname[], int M, int N, int nz, int I[], int J[],
        double val[], MM_typecode matcode)
{
    FILE *f;
    int i;
    char *tmp;

    if (strcmp(fname, "stdout") == 0) 
        f = stdout;
    else
    if ((f = fopen(fname, "w")) == NULL)
        return MM_COULD_NOT_WRITE_FILE;
    
    /* print banner followed by typecode */
    fprintf(f, "%s ", MatrixMarketBanner);
    tmp = mm_typecode_to_str(matcode);
    fprintf(f, "%s\n", tmp);
    if (tmp) free(tmp);

    /* print matrix sizes and nonzeros */
    fprintf(f, "%d %d %d\n", M, N, nz);

    /* print values */
    if (mm_is_pattern(matcode))
        for (i=0; i<nz; i++)
            fprintf(f, "%d %d\n", I[i], J[i]);
    else
    if (mm_is_real(matcode))
        for (i=0; i<nz; i++)
            fprintf(f, "%d %d %20.16g\n", I[i], J[i], val[i]);
    else
    if (mm_is_complex(matcode))
        for (i=0; i<nz; i++)
            fprintf(f, "%d %d %20.16g %20.16g\n", I[i], J[i], val[2*i], 
                        val[2*i+1]);
    else
    {
        if (f != stdout) fclose(f);
        return MM_UNSUPPORTED_TYPE;
    }

    if (f !=stdout) fclose(f);

    return 0;
}
    

char  *mm_typecode_to_str(MM_typecode matcode)
{
    char buffer[MM_MAX_LINE_LENGTH];
    char *types[4];
    int error =0;

    /* check for MTX type */
    if (mm_is_matrix(matcode)) 
        types[0] = MM_MTX_STR;
    else
        error=1;

    /* check for CRD or ARR matrix */
    if (mm_is_sparse(matcode))
        types[1] = MM_SPARSE_STR;
    else
    if (mm_is_dense(matcode))
        types[1] = MM_DENSE_STR;
    else
        return NULL;

    /* check for element data type */
    if (mm_is_real(matcode))
        types[2] = MM_REAL_STR;
    else
    if (mm_is_complex(matcode))
        types[2] = MM_COMPLEX_STR;
    else
    if (mm_is_pattern(matcode))
        types[2] = MM_PATTERN_STR;
    else
    if (mm_is_integer(matcode))
        types[2] = MM_INT_STR;
    else
        return NULL;


    /* check for symmetry type */
    if (mm_is_general(matcode))
        types[3] = MM_GENERAL_STR;
    else
    if (mm_is_symmetric(matcode))
        types[3] = MM_SYMM_STR;
    else 
    if (mm_is_hermitian(matcode))
        types[3] = MM_HERM_STR;
    else 
    if (mm_is_skew(matcode))
        types[3] = MM_SKEW_STR;
    else
        return NULL;

    sprintf(buffer,"%s %s %s %s", types[0], types[1], types[2], types[3]);
    return strdup(buffer);

}