style_cascade.h

/*
**  UICore
**  Copyright (c) 1997-2015 The UICore Team
**
**  This software is provided 'as-is', without any express or implied
**  warranty.  In no event will the authors be held liable for any damages
**  arising from the use of this software.
**
**  Permission is granted to anyone to use this software for any purpose,
**  including commercial applications, and to alter it and redistribute it
**  freely, subject to the following restrictions:
**
**  1. The origin of this software must not be misrepresented; you must not
**     claim that you wrote the original software. If you use this software
**     in a product, an acknowledgment in the product documentation would be
**     appreciated but is not required.
**  2. Altered source versions must be plainly marked as such, and must not be
**     misrepresented as being the original software.
**  3. This notice may not be removed or altered from any source distribution.
**
**  Note: Some of the libraries UICore may link to may have additional
**  requirements or restrictions.
**
**  File Author(s):
**
**    Magnus Norddahl
*/

#pragma once

#include <memory>
#include <string>
#include <vector>
#include "style_get_value.h"

namespace uicore
{
    class Style;
    class StyleGetValue;
    class Canvas;
    typedef std::shared_ptr<Canvas> CanvasPtr;
    class Font;
    typedef std::shared_ptr<Font> FontPtr;
    class ViewGeometry;

#if defined(MICROSOFT_FINALLY_IMPLEMENTED_CONSTEXPR_TEN_YEARS_AFTER_EVERYONE_ELSE)
    class PropertyNameConst
    {
    public:
        template<std::size_t Length>
        constexpr PropertyNameConst(const char(&text)[Length]) : text(text), length(Length - 1) { }

        constexpr char operator[](std::size_t index) const { return index < length ? text[index] : throw std::out_of_range("PropertyNameConst operator[] out of bounds"); }
        constexpr std::size_t size() const { return length; }
        constexpr std::size_t hash() const { return hash(2166136261U, 0); }

    private:
        constexpr std::size_t hash(std::size_t value, std::size_t index) const { return index == length ? value : hash((value ^ (std::size_t)text[index]) * 16777619U, index + 1); }

        const char * const text;
        const std::size_t length;
    };
#endif

    class StyleCascade
    {
    public:
        StyleCascade() { }
        StyleCascade(std::vector<Style *> cascade, const StyleCascade *parent = nullptr) : cascade(std::move(cascade)), parent(parent) { }

        std::vector<Style *> cascade;

        const StyleCascade *parent = nullptr;
        
        StyleGetValue cascade_value(const char *property_name) const;
        StyleGetValue cascade_value(const std::string &property_name) const { return cascade_value(property_name.c_str()); }

        StyleGetValue specified_value(const char *property_name) const;
        StyleGetValue specified_value(const std::string &property_name) const { return specified_value(property_name.c_str()); }

        StyleGetValue computed_value(const char *property_name) const;
        StyleGetValue computed_value(const std::string &property_name) const { return computed_value(property_name.c_str()); }
        
        StyleGetValue compute_length(const StyleGetValue &length) const;

        StyleGetValue compute_angle(const StyleGetValue &angle) const;

        StyleGetValue compute_time(const StyleGetValue &time) const;

        StyleGetValue compute_frequency(const StyleGetValue &frequency) const;

        StyleGetValue compute_resolution(const StyleGetValue &resolution) const;
        
        int array_size(const char *property_name) const;
        int array_size(const std::string &property_name) const { return array_size(property_name.c_str()); }
        
        void render_background(const CanvasPtr &canvas, const ViewGeometry &geometry) const;

        void render_border(const CanvasPtr &canvas, const ViewGeometry &geometry) const;
        
        FontPtr font() const;
    };
}