/***************************************************************************
 *   Copyright (c) 2009 Jürgen Riegel <FreeCAD@juergen-riegel.net>         *
 *                                                                         *
 *   This file is part of the FreeCAD CAx development system.              *
 *                                                                         *
 *   This library is free software; you can redistribute it and/or         *
 *   modify it under the terms of the GNU Library General Public           *
 *   License as published by the Free Software Foundation; either          *
 *   version 2 of the License, or (at your option) any later version.      *
 *                                                                         *
 *   This library  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 Library General Public License for more details.                  *
 *                                                                         *
 *   You should have received a copy of the GNU Library General Public     *
 *   License along with this library; see the file COPYING.LIB. If not,    *
 *   write to the Free Software Foundation, Inc., 59 Temple Place,         *
 *   Suite 330, Boston, MA  02111-1307, USA                                *
 *                                                                         *
 ***************************************************************************/


#include "PreCompiled.h"
#ifdef __GNUC__
# include <unistd.h>
#endif

#include <CXX/WrapPython.h>
#include <memory>
#include <QString>
#include "Exception.h"

#include "UnitsApi.h"
#include "UnitsSchemaCentimeters.h"
#include "UnitsSchemaInternal.h"
#include "UnitsSchemaImperial1.h"
#include "UnitsSchemaMKS.h"
#include "UnitsSchemaMmMin.h"
#include "UnitsSchemaFemMilliMeterNewton.h"

#ifndef M_PI
#define M_PI       3.14159265358979323846
#endif
#ifndef M_E
#define M_E        2.71828182845904523536
#endif
#ifndef  DOUBLE_MAX
# define DOUBLE_MAX 1.7976931348623157E+308    /* max decimal value of a "double"*/
#endif
#ifndef  DOUBLE_MIN
# define DOUBLE_MIN 2.2250738585072014E-308    /* min decimal value of a "double"*/
#endif

using namespace Base;

// === static attributes  ================================================

UnitsSchemaPtr  UnitsApi::UserPrefSystem(new UnitsSchemaInternal());
UnitSystem    UnitsApi::currentSystem = UnitSystem::SI1;

int UnitsApi::UserPrefDecimals = 2;

const char* UnitsApi::getDescription(UnitSystem system)
{
    switch (system) {
    case UnitSystem::SI1:
        return "Standard (mm/kg/s/degree)";
    case UnitSystem::SI2:
        return "MKS (m/kg/s/degree)";
    case UnitSystem::Imperial1:
        return "US customary (in/lb)";
    case UnitSystem::ImperialDecimal:
        return "Imperial decimal (in/lb)";
    case UnitSystem::Centimeters:
        return "Building Euro (cm/m²/m³)";
    case UnitSystem::ImperialBuilding:
        return "Building US (ft-in/sqft/cft)";
    case UnitSystem::MmMin:
        return "Metric small parts & CNC(mm, mm/min)";
    case UnitSystem::ImperialCivil:
        return "Imperial for Civil Eng (ft, ft/sec)";
    case UnitSystem::FemMilliMeterNewton:
        return "FEM (mm, N, s)";
    default:
        return "Unknown schema";
    }
}

UnitsSchemaPtr UnitsApi::createSchema(UnitSystem s)
{
    switch (s) {
    case UnitSystem::SI1:
        return std::make_unique<UnitsSchemaInternal>();
    case UnitSystem::SI2:
        return std::make_unique<UnitsSchemaMKS>();
    case UnitSystem::Imperial1:
        return std::make_unique<UnitsSchemaImperial1>();
    case UnitSystem::ImperialDecimal:
        return std::make_unique<UnitsSchemaImperialDecimal>();
    case UnitSystem::Centimeters:
        return std::make_unique<UnitsSchemaCentimeters>();
    case UnitSystem::ImperialBuilding:
        return std::make_unique<UnitsSchemaImperialBuilding>();
    case UnitSystem::MmMin:
        return std::make_unique<UnitsSchemaMmMin>();
    case UnitSystem::ImperialCivil:
        return std::make_unique<UnitsSchemaImperialCivil>();
    case UnitSystem::FemMilliMeterNewton:
        return std::make_unique<UnitsSchemaFemMilliMeterNewton>();
    default:
        break;
    }

    return nullptr;
}

void UnitsApi::setSchema(UnitSystem s)
{
    if (UserPrefSystem) {
        UserPrefSystem->resetSchemaUnits(); // for schemas changed the Quantity constants
    }

    UserPrefSystem = createSchema(s);
    currentSystem = s;

    // for wrong value fall back to standard schema
    if (!UserPrefSystem) {
        UserPrefSystem = std::make_unique<UnitsSchemaInternal>();
        currentSystem = UnitSystem::SI1;
    }

    UserPrefSystem->setSchemaUnits(); // if necessary a unit schema can change the constants in Quantity (e.g. mi=1.8km rather then 1.6km).
}

QString UnitsApi::toString(const Base::Quantity& q, const QuantityFormat& f)
{
    QString value = QString::fromLatin1("'%1 %2'").arg(q.getValue(), 0, f.toFormat(), f.precision)
                                                  .arg(q.getUnit().getString());
    return value;
}

QString UnitsApi::toNumber(const Base::Quantity& q, const QuantityFormat& f)
{
    return toNumber(q.getValue(), f);
}

QString UnitsApi::toNumber(double d, const QuantityFormat& f)
{
    QString number = QString::fromLatin1("%1").arg(d, 0, f.toFormat(), f.precision);
    return number;
}

//return true if the current user schema uses multiple units for length (ex. Ft/In)
bool UnitsApi::isMultiUnitLength()
{
    return UserPrefSystem->isMultiUnitLength();
}

//return true if the current user schema uses multiple units for angles (ex. DMS)
bool UnitsApi::isMultiUnitAngle()
{
    return UserPrefSystem->isMultiUnitAngle();
}

// === static translation methods ==========================================

QString UnitsApi::schemaTranslate(const Base::Quantity& quant, double &factor, QString &unitString)
{
    return UserPrefSystem->schemaTranslate(quant,factor,unitString);
}

double UnitsApi::toDouble(PyObject *ArgObj, const Base::Unit &u)
{
    if (PyUnicode_Check(ArgObj)) {
        QString str = QString::fromUtf8(PyUnicode_AsUTF8(ArgObj));
        // Parse the string
        Quantity q = Quantity::parse(str);
        if (q.getUnit() == u)
            return q.getValue();
        throw Base::UnitsMismatchError("Wrong unit type!");
    }
    else if (PyFloat_Check(ArgObj)) {
        return PyFloat_AsDouble(ArgObj);
    }
    else if (PyLong_Check(ArgObj)) {
        return static_cast<double>(PyLong_AsLong(ArgObj));
    }
    else {
        throw Base::UnitsMismatchError("Wrong parameter type!");
    }
}

Quantity UnitsApi::toQuantity(PyObject *ArgObj, const Base::Unit &u)
{
    double d;
    if (PyUnicode_Check(ArgObj)) {
        QString str = QString::fromUtf8(PyUnicode_AsUTF8(ArgObj));
        // Parse the string
        Quantity q = Quantity::parse(str);
        d = q.getValue();
    }
    else if (PyFloat_Check(ArgObj)) {
        d = PyFloat_AsDouble(ArgObj);
    }
    else if (PyLong_Check(ArgObj)) {
        d = static_cast<double>(PyLong_AsLong(ArgObj));
    }
    else {
        throw Base::UnitsMismatchError("Wrong parameter type!");
    }

    return Quantity(d,u);
}

void UnitsApi::setDecimals(int prec)
{
    UserPrefDecimals = prec;
}

int UnitsApi::getDecimals()
{
    return UserPrefDecimals;
}