/****************************************
                *                                      *
                *               Seifert                *
                *                                      *
                *     A C++ program  for computing     *
                *      a Seifert matrix of a knot      *
                *                                      *
                *       by Morwen Thistlethwaite       *
                *                                      *
                ****************************************/



#include "link_diagram.h"
#include <cstdio>
#include <cstdlib>
#include <string>

FILE *fp, *gp;
int knotid;       //  (making this global is a cheap hack)


main( int argc, char **argv )
{
    int i, j, t, crossing_number, num_components;

    fp = fopen( argv[1], "r" );
    gp = fopen( argv[2], "w" );
    
    /*
     *  Little insert to test whether input file exists;
     *  comment out if it doesn't work on your system
     */

    std::string shell_query;
    
    shell_query = "test -f ";
    shell_query += argv[1];

    if ( system( shell_query.c_str() ) != 0 )
    {
        printf( "input file doesn't exist\n" );
        exit(0);
    }
    
    /*
     *  end of insert
     */
    
    while ( fscanf( fp, "%d%d", &crossing_number, &knotid ) != EOF )
    {
        std::vector<int> dt0;
        
        for ( i=0; i<=2*crossing_number; ++i ) dt0.push_back( 0 );
       
        dt0[0] = crossing_number;
        dt0[1] = num_components = 1;
        
        dt0[2] = 2*crossing_number;
    
        for ( i=3; i<crossing_number+num_components+2; ++i )
        {
            fscanf( fp, "%d", &t );
            dt0[i] = t;
        }
        
        Link *link = new Link( dt0 );
    
        link->make_geometry();
        
        link->make_seifert_matrix();
        
        link->write_script();
    
        delete link;

    }
    
}


/*
void Link::write_script()  //  this one for Maple
{
    int i, j;

    fprintf( gp, "%2d %7d    ", crossing_number, knotid );
    for ( i=1; i<=2*crossing_number-1; i+=2 ) fprintf( gp, "%4d", dowker[i]*alt_sign[i] );
    fprintf( gp, "\n\n" );
    
    fprintf( gp, "[" );

    for ( i=0; i<num_seifert_cycles; ++i )
    {
        if ( i > 0 ) fprintf( gp, " " );
        fprintf( gp, "[" );
        for ( j=0; j<num_seifert_cycles; ++j )
        {
            fprintf( gp, "%4d", seifert_matrix[i][j] );
            if ( j < num_seifert_cycles - 1) fprintf( gp, ", " );
            else if ( i < num_seifert_cycles - 1 ) fprintf( gp, "],\n" );
            else
            {
                fprintf( gp, "]]\n\n\n" );
            }
        }
    }
}
*/




void Link::write_script()  //  this one for Pari; if run in Pari, will print
{                          //  Alexander polynomials
    int i, j;

    fprintf( gp, "{\n" );
    fprintf( gp, "v = [\n" );

    for ( i=0; i<num_seifert_cycles; ++i )
    {
        for ( j=0; j<num_seifert_cycles; ++j )
        {
            fprintf( gp, "%4d", seifert_matrix[i][j] );
            if ( j < num_seifert_cycles - 1) fprintf( gp, ", " );
            else if ( i < num_seifert_cycles - 1 ) fprintf( gp, ";\n" );
            else
            {
                fprintf( gp, "\n" );
                fprintf( gp, "];\n" );
            }
        }
    }

    fprintf( gp, "p = matdet(t*v - mattranspose(v));\n" );
    fprintf( gp, "for(i=0,poldegree(p),print1(polcoeff(p,poldegree(p)-i),\"  \"));\n" );
    fprintf( gp, "print;\n" );
    fprintf( gp, "}\n\n" );
}