value.h

/*
 * Copyright (C) 2018 Microchip Technology Inc.  All rights reserved.
 *
 * SPDX-License-Identifier: Apache-2.0
 */
#ifndef EGT_VALUE_H
#define EGT_VALUE_H
 
#include <cassert>
#include <egt/animation.h>
#include <egt/detail/math.h>
#include <egt/object.h>
#include <egt/signal.h>
 
namespace egt
{
inline namespace v1
{
 
template<class T>
class Value : public Object
{
public:
 
    Signal<> on_value_changed;
    explicit Value(T value = {}) noexcept
        : m_value(value)
    {
    }
 
    explicit operator T() const
    {
        return m_value;
    }
 
    Value<T>& operator=(T value)
    {
        value(value);
        return *this;
    }
 
    T value() const { return m_value; }
 
    bool value(T value)
    {
        if (detail::change_if_diff<T>(m_value, value))
        {
            on_value_changed.invoke();
            return true;
        }
 
        return false;
    }
 
protected:
 
    T m_value{};
};
 
template<class T>
class RangeValue : public Object
{
public:
 
    Signal<> on_value_changed;
    RangeValue(T start, T end, T value = {}) noexcept
        : m_start(start),
          m_end(end)
    {
        if (m_start < m_end)
            value = detail::clamp<T>(value, m_start, m_end);
        else
            value = detail::clamp<T>(value, m_end, m_start);
 
        m_value = value;
    }
 
    explicit operator T() const
    {
        return m_value;
    }
 
    RangeValue<T>& operator=(T value)
    {
        value(value);
        return *this;
    }
 
    EGT_NODISCARD T value() const { return m_value; }
 
    bool value(T value)
    {
        if (m_start < m_end)
            value = detail::clamp<T>(value, m_start, m_end);
        else
            value = detail::clamp<T>(value, m_end, m_start);
 
        if (detail::change_if_diff<T>(m_value, value))
        {
            on_value_changed.invoke();
            return true;
        }
 
        return false;
    }
 
    EGT_NODISCARD T start() const { return m_start; }
 
    void start(T start)
    {
        if (detail::change_if_diff<>(m_start, start))
            value(m_value);
    }
 
    EGT_NODISCARD T end() const { return m_end; }
 
    void end(T end)
    {
        if (detail::change_if_diff<>(m_end, end))
            value(m_value);
    }
 
protected:
 
    T m_start{};
 
    T m_end{};
 
    T m_value{};
};
 
}
}
 
#endif