/* This file is part of the KDE project
 * Copyright (C) 2007 Jan Hambrecht <jaham@gmx.net>
 *
 * 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., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 */

#ifndef KOENHANCEDPATHPARAMETER_H
#define KOENHANCEDPATHPARAMETER_H

#include <QString>

class EnhancedPathShape;

/// the different possible identifiers, taken from the odf spec
enum Identifier {
    IdentifierUnknown,   ///< unknown identifier
    IdentifierPi,        ///< value of pi.
    IdentifierLeft,      ///< left of svg:viewBox or draw:coordinate-origin-x
    IdentifierTop,       ///< top of svg:viewBox or draw:coordinate-origin-y
    IdentifierRight,     ///< right of svg:viewBox or draw:coordinate-origin-x + draw:coordinate-width
    IdentifierBottom,    ///< bottom of svg:viewBox or draw:coordinate-origin-y + draw:coordinate-height
    IdentifierXstretch,  ///< The value of draw:path-stretchpoint-x is used.
    IdentifierYstretch,  ///< The value of draw:path-stretchpoint-y is used.
    IdentifierHasStroke, ///< If the shape has a line style, a value of 1 is used.
    IdentifierHasFill,   ///< If the shape has a fill style, a value of 1 is used.
    IdentifierWidth,     ///< The width of the svg:viewBox is used.
    IdentifierHeight,    ///< The height of the svg:viewBox is used.
    IdentifierLogwidth,  ///< The width of the svg:viewBox in 1/100th mm is used.
    IdentifierLogheight  ///< The height of the svg:viewBox in 1/100th mm is used.
};

/// The bstract parameter class
class EnhancedPathParameter
{
public:
    explicit EnhancedPathParameter(EnhancedPathShape *parent);
    virtual ~EnhancedPathParameter();
    /// evaluates the parameter using the given path
    virtual qreal evaluate() = 0;
    /// modifies the parameter if possible, using the new value
    virtual void modify(qreal value);
    /// returns string representation of the parameter
    virtual QString toString() const = 0;
protected:
    EnhancedPathShape *parent();
private:
    EnhancedPathShape *m_parent;
};

/// A constant parameter, a fixed value (i.e. 5, 11.3, -7)
class EnhancedPathConstantParameter : public EnhancedPathParameter
{
public:
    /// Constructs the constant parameter with the given value
    EnhancedPathConstantParameter(qreal value, EnhancedPathShape *parent);
    qreal evaluate() override;
    QString toString() const override;
private:
    qreal m_value; ///< the constant value
};

/// A named parameter, one that refers to a variable of the path
class EnhancedPathNamedParameter : public EnhancedPathParameter
{
public:
    /// Constructs named parameter from given identifier
    EnhancedPathNamedParameter(Identifier identifier, EnhancedPathShape *parent);
    /// Constructs named parameter from given identifier string
    EnhancedPathNamedParameter(const QString &identifier, EnhancedPathShape *parent);
    qreal evaluate() override;
    /// Returns identfier type from given string
    static Identifier identifierFromString(const QString &text);
    QString toString() const override;
private:
    Identifier m_identifier; ///< the identifier type
};

/// A referencing parameter, one that references another formula or a modifier
class EnhancedPathReferenceParameter : public EnhancedPathParameter
{
public:
    /// Constructs reference parameter from the given reference string
    explicit EnhancedPathReferenceParameter(const QString &reference, EnhancedPathShape *parent);
    qreal evaluate() override;
    void modify(qreal value) override;
    QString toString() const override;
private:
    QString m_reference; ///< the reference, formula or modifier
};

#endif // KOENHANCEDPATHPARAMETER_H
