#include "xml.h"
#include "PureFluidPhase.h"

#include "../../ext/tpx/Sub.h"
#include "../../ext/tpx/utils.h"

namespace Cantera {

    PureFluidPhase::~PureFluidPhase() { delete m_sub; }

    void PureFluidPhase::
    initThermo() {
        if (m_sub) delete m_sub;
        m_sub = tpx::GetSub(m_subflag);
        if (m_sub == 0) {
            throw CanteraError("PureFluidPhase::initThermo",
                "could not create new substance object.");
        }
        m_mw = m_sub->MolWt();
        m_weight[0] = m_mw;
        setMolecularWeight(0,m_mw);
        double one = 1.0;
        setMoleFractions(&one);
        double cp0_R, h0_RT, s0_R, T0, p;
        T0 = 298.15;
        if (T0 < m_sub->Tcrit()) {
            m_sub->Set(tpx::TX, T0, 1.0);
            p = 0.01*m_sub->P();
        }
        else {
            p = 0.001*m_sub->Pcrit();
        }
        m_sub->Set(tpx::TP, T0, p);
        
        m_spthermo->update_one(0, T0, &cp0_R, &h0_RT, &s0_R);
        double s_R = s0_R - log(p/refPressure());
        m_sub->setStdState(h0_RT*GasConstant*298.15/m_mw,
            s_R*GasConstant/m_mw, T0, p);
        if (m_verbose) {
            writelog("PureFluidPhase::initThermo: initialized phase "
                +id()+"\n");
        }
    }

    void PureFluidPhase::
    setParametersFromXML(const XML_Node& eosdata) {
        eosdata._require("model","PureFluid");
        m_subflag = atoi(eosdata["fluid_type"].c_str());
        if (m_subflag < 0) 
            throw CanteraError("PureFluidPhase::setParametersFromXML",
                "missing or negative substance flag");
    }

    doublereal PureFluidPhase::
    enthalpy_mole() const {
        setTPXState();
        doublereal h = m_sub->h() * m_mw;
        check(h);
        return h;            
    }
        
    doublereal PureFluidPhase::
    intEnergy_mole() const {
        setTPXState();
        doublereal u = m_sub->u() * m_mw;
        check(u);
        return u;            
    }

    doublereal PureFluidPhase::
    entropy_mole() const {
        setTPXState();
        doublereal s = m_sub->s() * m_mw;
        check(s);
        return s;            
    }

    doublereal PureFluidPhase::
    gibbs_mole() const {
        setTPXState();
        doublereal g = m_sub->g() * m_mw;
        check(g);
        return g;            
    }

    doublereal PureFluidPhase::
    cp_mole() const {
        setTPXState();
        doublereal cp = m_sub->cp() * m_mw;
        check(cp);
        return cp;            
    }

    doublereal PureFluidPhase::
    cv_mole() const {
        setTPXState();
        doublereal cv = m_sub->cv() * m_mw;
        check(cv);
        return cv;
    }
        
    doublereal PureFluidPhase::
    pressure() const {
        setTPXState();
        doublereal p = m_sub->P();
        check(p);
        return p;
    }
        
    void PureFluidPhase::
    setPressure(doublereal p) {
        Set(tpx::TP, temperature(), p);
        setDensity(1.0/m_sub->v());
        check();
    }

    void PureFluidPhase::Set(int n, double x, double y) const {
        try { 
            m_sub->Set(n, x, y); 
        }
        catch(tpx::TPX_Error) {
            reportTPXError();
        }
    }
            
    void PureFluidPhase::setTPXState() const {
        Set(tpx::TV, temperature(), 1.0/density());
    }
        
    void PureFluidPhase::check(doublereal v) const {
        if (m_sub->Error() || v == tpx::Undef) {
            throw CanteraError("PureFluidPhase",string(tpx::errorMsg(
                                                           m_sub->Error())));
        }
    }

    void PureFluidPhase::reportTPXError() const {
        string msg = tpx::TPX_Error::ErrorMessage;
        string proc = "tpx::"+tpx::TPX_Error::ErrorProcedure;
        throw CanteraError(proc,msg);
    }


    doublereal PureFluidPhase::isothermalCompressibility() const {
        return m_sub->isothermalCompressibility();
    }

    doublereal PureFluidPhase::thermalExpansionCoeff() const {
        return m_sub->thermalExpansionCoeff();
    }

    tpx::Substance& PureFluidPhase::TPX_Substance() { return *m_sub; }

    /// critical temperature 
    doublereal PureFluidPhase::critTemperature() const { return m_sub->Tcrit(); }
        
    /// critical pressure
    doublereal PureFluidPhase::critPressure() const { return m_sub->Pcrit(); }
        
    /// critical density
    doublereal PureFluidPhase::critDensity() const { return 1.0/m_sub->Vcrit(); }
        
        
    /// saturation temperature
    doublereal PureFluidPhase::satTemperature(doublereal p) const { 
        try {
            doublereal ts = m_sub->Tsat(p);
            return ts;
        }
        catch(tpx::TPX_Error) {
            reportTPXError();
            return -1.0;
        }
    }
        
    void PureFluidPhase::setState_HP(doublereal h, doublereal p, 
        doublereal tol) {
        Set(tpx::HP, h, p);
        setState_TR(m_sub->Temp(), 1.0/m_sub->v());
        check();
    }

    void PureFluidPhase::setState_UV(doublereal u, doublereal v, 
        doublereal tol) {
        Set(tpx::UV, u, v);
        setState_TR(m_sub->Temp(), 1.0/m_sub->v());
        check();
    }

    void PureFluidPhase::setState_SV(doublereal s, doublereal v, 
        doublereal tol) {
        Set(tpx::SV, s, v);
        setState_TR(m_sub->Temp(), 1.0/m_sub->v());
        check();
    }

    void PureFluidPhase::setState_SP(doublereal s, doublereal p, 
        doublereal tol) {
        Set(tpx::SP, s, p);
        setState_TR(m_sub->Temp(), 1.0/m_sub->v());
        check();
    }

    /// saturation pressure
    doublereal PureFluidPhase::satPressure(doublereal t) const {
        doublereal vsv = m_sub->v();
        try {
            Set(tpx::TV,t,vsv);
            doublereal ps = m_sub->Ps();
            return ps;
        }
        catch(tpx::TPX_Error) {
            reportTPXError();
            return -1.0;
        }
    }
        
    doublereal PureFluidPhase::vaporFraction() const {
        setTPXState();
        doublereal x = m_sub->x();
        check(x);
        return x;
    }
        
    void PureFluidPhase::setState_Tsat(doublereal t, doublereal x) {
        setTemperature(t);
        setTPXState();
        Set(tpx::TX, t, x);
        setDensity(1.0/m_sub->v());
        check();
    }

    void PureFluidPhase::setState_Psat(doublereal p, doublereal x) {
        setTPXState();
        Set(tpx::PX, p, x);
        setTemperature(m_sub->Temp());
        setDensity(1.0/m_sub->v());
        check();
    }

}