/*
 * Copyright (c) 2022, Andreas Kling <kling@serenityos.org>
 * Copyright (c) 2023, Sam Atkins <atkinssj@serenityos.org>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#pragma once

#include <LibWeb/CSS/Length.h>
#include <LibWeb/CSS/PercentageOr.h>

namespace Web::CSS {

class Size {
public:
    enum class Type {
        Auto,
        Calculated,
        Length,
        Percentage,
        MinContent,
        MaxContent,
        FitContent,
        None, // NOTE: This is only valid for max-width and max-height.
    };

    static Size make_auto();
    static Size make_px(CSSPixels);
    static Size make_length(Length);
    static Size make_percentage(Percentage);
    static Size make_calculated(NonnullRefPtr<CalculatedStyleValue>);
    static Size make_min_content();
    static Size make_max_content();
    static Size make_fit_content(Length available_space);
    static Size make_none();

    bool is_auto() const { return m_type == Type::Auto; }
    bool is_calculated() const { return m_type == Type::Calculated; }
    bool is_length() const { return m_type == Type::Length; }
    bool is_percentage() const { return m_type == Type::Percentage; }
    bool is_min_content() const { return m_type == Type::MinContent; }
    bool is_max_content() const { return m_type == Type::MaxContent; }
    bool is_fit_content() const { return m_type == Type::FitContent; }
    bool is_none() const { return m_type == Type::None; }

    // FIXME: This is a stopgap API that will go away once all layout code is aware of CSS::Size.
    CSS::Length resolved(Layout::Node const&, Length const& reference_value) const;

    [[nodiscard]] CSSPixels to_px(Layout::Node const&, CSSPixels reference_value) const;

    bool contains_percentage() const;

    CalculatedStyleValue const& calculated() const
    {
        VERIFY(is_calculated());
        return m_length_percentage.calculated();
    }

    CSS::Length const& length() const
    {
        VERIFY(is_length());
        return m_length_percentage.length();
    }

    CSS::Percentage const& percentage() const
    {
        VERIFY(is_percentage());
        return m_length_percentage.percentage();
    }

    CSS::Length const& fit_content_available_space() const
    {
        VERIFY(is_fit_content());
        return m_length_percentage.length();
    }

    ErrorOr<String> to_string() const;

private:
    Size(Type type, LengthPercentage);

    Type m_type {};
    CSS::LengthPercentage m_length_percentage;
};

}

template<>
struct AK::Formatter<Web::CSS::Size> : Formatter<StringView> {
    ErrorOr<void> format(FormatBuilder& builder, Web::CSS::Size const& size)
    {
        return Formatter<StringView>::format(builder, TRY(size.to_string()));
    }
};