#ifndef _FGFDM_HPP
#define _FGFDM_HPP

#include <simgear/xml/easyxml.hxx>
#include <simgear/props/props.hxx>

#include "Airplane.hpp"
#include "Vector.hpp"

namespace yasim {

class Wing;
class Version;

// This class forms the "glue" to the FlightGear codebase.  It handles
// parsing of XML airplane files, interfacing to the properties
// system, and providing data for the use of the FGInterface object.
class FGFDM : public XMLVisitor {
public:
    FGFDM();
    ~FGFDM();
    void init();
    void iterate(float dt);
    void getExternalInput(float dt=1e6);

    Airplane* getAirplane();

    // XML parsing callback from XMLVisitor
    virtual void startElement(const char* name, const XMLAttributes &atts);

    float getVehicleRadius(void) const { return _vehicle_radius; }

private:
    struct EngRec { char* prefix; Thruster* eng; };
    struct WeightRec { char* prop; float size; int handle; };
    struct PropOut { SGPropertyNode* prop; int handle, type; bool left;
                     float min, max; };

    void setOutputProperties(float dt);

    Rotor* parseRotor(XMLAttributes* a, const char* name);
    Wing* parseWing(XMLAttributes* a, const char* name, Version * version);
    int parseOutput(const char* name);
    void parseWeight(XMLAttributes* a);
    void parseTurbineEngine(XMLAttributes* a);
    void parsePistonEngine(XMLAttributes* a);
    void parsePropeller(XMLAttributes* a);
    bool eq(const char* a, const char* b);
    bool caseeq(const char* a, const char* b);
    char* dup(const char* s);
    int attri(XMLAttributes* atts, const char* attr);
    int attri(XMLAttributes* atts, const char* attr, int def); 
    float attrf(XMLAttributes* atts, const char* attr);
    float attrf(XMLAttributes* atts, const char* attr, float def); 
    double attrd(XMLAttributes* atts, const char* attr);
    double attrd(XMLAttributes* atts, const char* attr, double def); 
    bool attrb(XMLAttributes* atts, const char* attr);

    // The core Airplane object we manage.
    Airplane _airplane;

    // Aerodynamic turbulence model
    Turbulence* _turb;

    // Settable weights
    Vector _weights;

    // Engine types.  Contains an EngRec structure.
    Vector _thrusters;

    // Output properties for the ControlMap
    Vector _controlProps;

    // Radius of the vehicle, for intersection testing.
    float _vehicle_radius;

    // Parsing temporaries
    void* _currObj;
    bool _cruiseCurr;
    int _nextEngine;

    class FuelProps
    {
    public:
        SGPropertyNode_ptr _out_of_fuel;
        SGPropertyNode_ptr _fuel_consumed_lbs;
    };

    class ThrusterProps
    {
    public:
        SGPropertyNode_ptr _running, _cranking;
        SGPropertyNode_ptr _prop_thrust, _thrust_lbs, _fuel_flow_gph;
        SGPropertyNode_ptr _rpm, _torque_ftlb, _mp_osi, _mp_inhg;
        SGPropertyNode_ptr _oil_temperature_degf, _boost_gauge_inhg;
        SGPropertyNode_ptr _n1, _n2, _epr, _egt_degf;
    };

    SGPropertyNode_ptr _turb_magnitude_norm, _turb_rate_hz;
    SGPropertyNode_ptr _gross_weight_lbs;
    SGPropertyNode_ptr _cg_x;
    SGPropertyNode_ptr _cg_y;
    SGPropertyNode_ptr _cg_z;
    SGPropertyNode_ptr _yasimN;

    std::vector<SGPropertyNode_ptr> _tank_level_lbs;
    std::vector<ThrusterProps> _thrust_props;
    std::vector<FuelProps> _fuel_props;
};

}; // namespace yasim
#endif // _FGFDM_HPP