/*
 *~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 *<LicenseText>
 *
 * CitcomS by Louis Moresi, Shijie Zhong, Lijie Han, Eh Tan,
 * Clint Conrad, Michael Gurnis, and Eun-seo Choi.
 * Copyright (C) 1994-2005, California Institute of Technology.
 *
 * 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, 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 General Public License for more details.
 *
 * You should have received a copy of the GNU 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
 *
 *</LicenseText>
 *
 *~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <math.h>

#include "global_defs.h"
#include "material_properties.h"
#include "parallel_related.h"

static void read_refstate(struct All_variables *E);
static void adams_williamson_eos(struct All_variables *E);
static void murnaghan_eos(struct All_variables *E);

int layers_r(struct All_variables *,float);
void myerror(struct All_variables *E,char *message);

void mat_prop_allocate(struct All_variables *E)
{
    int noz = E->lmesh.noz;
    int nno = E->lmesh.nno;
    int nel = E->lmesh.nel;

    /* reference profile of density */
    E->refstate.rho = (double *) malloc((noz+1)*sizeof(double));

    /* reference profile of gravity */
    E->refstate.gravity = (double *) malloc((noz+1)*sizeof(double));

    /* reference profile of coefficient of thermal expansion */
    E->refstate.thermal_expansivity = (double *) malloc((noz+1)*sizeof(double));

    /* reference profile of heat capacity */
    E->refstate.heat_capacity = (double *) malloc((noz+1)*sizeof(double));

    /* reference profile of thermal conductivity */
    /*E->refstate.thermal_conductivity = (double *) malloc((noz+1)*sizeof(double));*/

    /* reference profile of temperature */
    /*E->refstate.Tadi = (double *) malloc((noz+1)*sizeof(double));*/

}


void reference_state(struct All_variables *E)
{
    int i;

    /* All refstate variables (except Tadi) must be 1 at the surface.
     * Otherwise, the scaling of eqns in the code might not be correct. */

    /* select the choice of reference state */
    switch(E->refstate.choice) {
    case 0:
        /* read from a file */
        read_refstate(E);
        break;
    case 1:
        /* Adams-Williamson EoS */
        adams_williamson_eos(E);
        break;
    case 2:
        /* Murnaghan's integrated linear EoS + constant Gruneisen parameter */
        murnaghan_eos(E);
        break;
    default:
        if (E->parallel.me) {
            fprintf(stderr, "Unknown option for reference state\n");
            fprintf(E->fp, "Unknown option for reference state\n");
            fflush(E->fp);
        }
        parallel_process_termination();
    }

    if(E->parallel.me == 0) {
      fprintf(stderr, "   nz     radius      depth    rho              layer\n");
    }
    if(E->parallel.me < E->parallel.nprocz)
        for(i=1; i<=E->lmesh.noz; i++) {
            fprintf(stderr, "%6d %11f %11f %11e %5i\n",
                    i+E->lmesh.nzs-1, E->sx[1][3][i], 1-E->sx[1][3][i],
                    E->refstate.rho[i],layers_r(E,E->sx[1][3][i]));
        }

    return;
}


static void read_refstate(struct All_variables *E)
{
    FILE *fp;
    int i;
    char buffer[255];
    double not_used1, not_used2, not_used3;

    fp = fopen(E->refstate.filename, "r");
    if(fp == NULL) {
        fprintf(stderr, "Cannot open reference state file: %s\n",
                E->refstate.filename);
        parallel_process_termination();
    }

    /* skip these lines, which belong to other processors */
    for(i=1; i<E->lmesh.nzs; i++) {
        fgets(buffer, 255, fp);
    }

    for(i=1; i<=E->lmesh.noz; i++) {
        fgets(buffer, 255, fp);
        if(sscanf(buffer, "%lf %lf %lf %lf %lf %lf %lf\n",
                  &(E->refstate.rho[i]),
                  &(E->refstate.gravity[i]),
                  &(E->refstate.thermal_expansivity[i]),
                  &(E->refstate.heat_capacity[i]),
                  &not_used1,
                  &not_used2,
                  &not_used3) != 7) {
            fprintf(stderr,"Error while reading file '%s'\n", E->refstate.filename);
            exit(8);
        }
        /**** debug ****
        fprintf(stderr, "%d %f %f %f %f\n",
                i,
                E->refstate.rho[i],
                E->refstate.gravity[i],
                E->refstate.thermal_expansivity[i],
                E->refstate.heat_capacity[i]);
        end of debug */
    }

    fclose(fp);
    return;
}


static void adams_williamson_eos(struct All_variables *E)
{
    int i;
    double r, z, beta;

    beta = E->control.disptn_number * E->control.inv_gruneisen;

    for(i=1; i<=E->lmesh.noz; i++) {
	r = E->sx[1][3][i];
	z = 1 - r;
	E->refstate.rho[i] = exp(beta*z);
	E->refstate.gravity[i] = 1;
	E->refstate.thermal_expansivity[i] = 1;
	E->refstate.heat_capacity[i] = 1;
	/*E->refstate.thermal_conductivity[i] = 1;*/
	/*E->refstate.Tadi[i] = (E->control.adiabaticT0 + E->control.surface_temp) * exp(E->control.disptn_number * z) - E->control.surface_temp;*/
    }

    return;
}


static void murnaghan_eos(struct All_variables *E)
{
    /* Reference: Murnaghan (1967), Finite Deformation of an Elastic Solid.

       Let K0' = dK/dP at P=0
           beta = dissipation number / Gruniesen parameter

       dP = rho * g * dr
       rho = rho0 * (1 + P * K0' / K0)^(1/K0')

       ==> non-dimensionalization
       rho = rho0 * (1 + beta * P * K0')^(1/K0')

       The non-linear ODE is intergated repeatedly to find
       convergence solution.


       Assuming Gruneisen parameter and Cp are constant:

       alpha = gamma * Cp * rho / Ks
    */

    const double k0p = 3.5;
    const double beta = E->control.disptn_number * E->control.inv_gruneisen;
    double *r, *rho, *p;

    const int gnoz = E->mesh.noz;

    int count = 0;
    int i, j;
    double old_rho_cmb, diff;
    const double acc = 1e-8;


    rho = (double *) malloc((gnoz+1)*sizeof(double));
    p = (double *) malloc((gnoz+1)*sizeof(double));

    if(rho == NULL || p == NULL) {
        myerror(E, "allocating memory in murnaghan_eos()");
    }

    for(i=1; i<=gnoz; i++) {
	rho[i] = 1;
        p[i] = 0;
    }

    r = E->sphere.gr;
    old_rho_cmb = 0;
    do {
        /* integrate downward from surface to CMB */
        for(i=gnoz-1; i>0; i--) {
            p[i] = p[i+1] + 0.5 * (rho[i] + rho[i+1]) * (r[i+1] - r[i]);
            rho[i] = rho[gnoz] * pow(1 + beta * k0p * p[i], 1.0/k0p);
        }

        diff = fabs(rho[1] - old_rho_cmb);
        old_rho_cmb = rho[1];
        count ++;

        /* The loop should converge within 50 iterations
           with reasonable beta and K0p */
        if(count > 50) myerror(E, "Murnaghan EoS cannot converge");
    } while(diff > acc);

    /*
    if(E->parallel.me == 0) {
        fprintf(stderr, "%d iterations\n", count);
        for(i=gnoz; i>0; i--) {
            fprintf(stderr, "%d %e %e %e\n", i, r[i], p[i], rho[i]);
        }
    }
    */

    for(i=1, j=E->lmesh.nzs; i<=E->lmesh.noz; i++, j++) {
        double ks;
	E->refstate.rho[i] = rho[j];
	E->refstate.gravity[i] = 1;
	E->refstate.heat_capacity[i] = 1;

        ks = pow(rho[j]/rho[gnoz], k0p);
	E->refstate.thermal_expansivity[i] = rho[j] / ks;

	/*E->refstate.thermal_conductivity[i] = 1;*/
	/*E->refstate.Tadi[i] = (E->control.adiabaticT0 + E->control.surface_temp) * exp(E->control.disptn_number * z) - E->control.surface_temp;*/
    }



    free(rho);
    free(p);

    return;
}