// Copyright (c) 2016-2019 Kiwano - Nomango
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

#pragma once
#include <kiwano/core/ObjectBase.h>
#include <kiwano/core/Time.h>
#include <kiwano/render/Brush.h>
#include <kiwano/render/Shape.h>
#include <kiwano/render/LayerArea.h>
#include <kiwano/render/TextLayout.h>
#include <kiwano/render/Texture.h>
#include <kiwano/render/DirectX/TextRenderer.h>

namespace kiwano
{
class Renderer;

KGE_DECLARE_SMART_PTR(RenderContext);

/**
 * \addtogroup Render
 * @{
 */

/// \~chinese
/// @brief 文字抗锯齿模式
enum class TextAntialiasMode
{
    Default,    ///< 系统默认
    ClearType,  ///< ClearType 抗锯齿
    GrayScale,  ///< 灰度抗锯齿
    None        ///< 不启用抗锯齿
};

/// \~chinese
/// @brief 渲染上下文
/// @details
/// 渲染上下文将完成基础图元的绘制，并将绘制结果输出到特定的目标中（如窗口或纹理）
class KGE_API RenderContext : public virtual ObjectBase
{
    friend class Renderer;

public:
    /// \~chinese
    /// @brief 是否有效
    bool IsValid() const;

    /// \~chinese
    /// @brief 开始渲染
    void BeginDraw();

    /// \~chinese
    /// @brief 结束渲染
    void EndDraw();

    /// \~chinese
    /// @brief 绘制纹理
    /// @param texture 纹理
    /// @param src_rect 源纹理裁剪矩形
    /// @param dest_rect 绘制的目标区域
    void DrawTexture(Texture const& texture, Rect const& src_rect, Rect const& dest_rect);

    /// \~chinese
    /// @brief 绘制纹理
    /// @param texture 纹理
    /// @param src_rect 源纹理裁剪矩形
    /// @param dest_rect 绘制的目标区域
    void DrawTexture(Texture const& texture, const Rect* src_rect = nullptr, const Rect* dest_rect = nullptr);

    /// \~chinese
    /// @brief 绘制文本布局
    /// @param layout 文本布局
    /// @param offset 偏移量
    void DrawTextLayout(TextLayout const& layout, Point const& offset = Point());

    /// \~chinese
    /// @brief 绘制形状轮廓
    /// @param shape 形状
    /// @param stroke 线条样式
    /// @param stroke_width 线条宽度
    void DrawShape(Shape const& shape, StrokeStylePtr stroke = nullptr, float stroke_width = 1.0f);

    /// \~chinese
    /// @brief 绘制线段
    /// @param point1 线段起点
    /// @param point2 线段终点
    /// @param stroke 线条样式
    /// @param stroke_width 线条宽度
    void DrawLine(Point const& point1, Point const& point2, StrokeStylePtr stroke = nullptr, float stroke_width = 1.0f);

    /// \~chinese
    /// @brief 绘制矩形边框
    /// @param rect 矩形
    /// @param stroke 线条样式
    /// @param stroke_width 线条宽度
    void DrawRectangle(Rect const& rect, StrokeStylePtr stroke = nullptr, float stroke_width = 1.0f);

    /// \~chinese
    /// @brief 绘制圆角矩形边框
    /// @param rect 矩形
    /// @param radius 圆角半径
    /// @param stroke 线条样式
    /// @param stroke_width 线条宽度
    void DrawRoundedRectangle(Rect const& rect, Vec2 const& radius, StrokeStylePtr stroke = nullptr,
                              float stroke_width = 1.0f);

    /// \~chinese
    /// @brief 绘制椭圆边框
    /// @param center 圆心
    /// @param radius 椭圆半径
    /// @param stroke 线条样式
    /// @param stroke_width 线条宽度
    void DrawEllipse(Point const& center, Vec2 const& radius, StrokeStylePtr stroke = nullptr,
                     float stroke_width = 1.0f);

    /// \~chinese
    /// @brief 填充形状
    /// @param shape 形状
    void FillShape(Shape const& shape);

    /// \~chinese
    /// @brief 填充矩形
    /// @param rect 矩形
    void FillRectangle(Rect const& rect);

    /// \~chinese
    /// @brief 填充圆角矩形
    /// @param rect 矩形
    /// @param radius 圆角半径
    void FillRoundedRectangle(Rect const& rect, Vec2 const& radius);

    /// \~chinese
    /// @brief 填充椭圆
    /// @param center 圆心
    /// @param radius 椭圆半径
    void FillEllipse(Point const& center, Vec2 const& radius);

    /// \~chinese
    /// @brief 创建纹理
    /// @param texture 纹理
    /// @param size 纹理像素大小
    void CreateTexture(Texture& texture, math::Vec2T<uint32_t> size);

    /// \~chinese
    /// @brief 设置绘制的裁剪区域
    /// @param clip_rect 裁剪矩形
    void PushClipRect(Rect const& clip_rect);

    /// \~chinese
    /// @brief 取消上一次设置的绘制裁剪区域
    void PopClipRect();

    /// \~chinese
    /// @brief 设置图层区域
    /// @param layer 图层区域
    void PushLayer(LayerArea& layer);

    /// \~chinese
    /// @brief 取消上一次设置的图层区域
    void PopLayer();

    /// \~chinese
    /// @brief 清空渲染内容
    void Clear();

    /// \~chinese
    /// @brief 使用纯色清空渲染内容
    /// @param clear_color 清屏颜色
    void Clear(Color const& clear_color);

    /// \~chinese
    /// @brief 获取渲染区域大小
    Size GetSize() const;

    /// \~chinese
    /// @brief 获取画刷透明度
    float GetBrushOpacity() const;

    /// \~chinese
    /// @brief 获取当前画刷
    BrushPtr GetCurrentBrush() const;

    /// \~chinese
    /// @brief 获取全局二维变换
    Matrix3x2 GetGlobalTransform() const;

    /// \~chinese
    /// @brief 设置画刷透明度
    void SetBrushOpacity(float opacity);

    /// \~chinese
    /// @brief 设置当前画刷
    void SetCurrentBrush(BrushPtr brush);

    /// \~chinese
    /// @brief 设置上下文的二维变换
    void SetTransform(const Matrix3x2& matrix);

    /// \~chinese
    /// @brief 设置全局二维变换
    void SetGlobalTransform(const Matrix3x2& matrix);

    /// \~chinese
    /// @brief 设置全局二维变换
    void SetGlobalTransform(const Matrix3x2* matrix);

    /// \~chinese
    /// @brief 设置抗锯齿模式
    void SetAntialiasMode(bool enabled);

    /// \~chinese
    /// @brief 设置文字抗锯齿模式
    void SetTextAntialiasMode(TextAntialiasMode mode);

    /// \~chinese
    /// @brief 检查边界是否在视区内
    bool CheckVisibility(Rect const& bounds, Matrix3x2 const& transform);

    /// \~chinese
    /// @brief 重设渲染上下文大小
    void Resize(Size const& size);

public:
    /// \~chinese
    /// @brief 渲染上下文状态
    struct Status
    {
        uint32_t primitives;  ///< 渲染图元数量
        Time     start;       ///< 渲染起始时间
        Duration duration;    ///< 渲染时长

        Status();
    };

    /// \~chinese
    /// @brief 启用或禁用状态收集功能
    void SetCollectingStatus(bool enable);

    /// \~chinese
    /// @brief 获取渲染上下文状态
    Status const& GetStatus() const;

protected:
    RenderContext();

    ComPtr<ID2D1RenderTarget> GetRenderTarget() const;

    ComPtr<ITextRenderer> GetTextRenderer() const;

private:
    /// \~chinese
    /// @brief 创建设备依赖资源
    HRESULT CreateDeviceResources(ComPtr<ID2D1Factory> factory, ComPtr<ID2D1RenderTarget> ctx);

    /// \~chinese
    /// @brief 销毁设备依赖资源
    void DiscardDeviceResources();

    /// \~chinese
    /// @brief 增加渲染图元数量
    void IncreasePrimitivesCount(uint32_t increase = 1) const;

    /// \~chinese
    /// @brief 保存绘制状态
    void SaveDrawingState();

    /// \~chinese
    /// @brief 恢复绘制状态
    void RestoreDrawingState();

private:
    bool              antialias_;
    bool              fast_global_transform_;
    mutable bool      collecting_status_;
    float             brush_opacity_;
    TextAntialiasMode text_antialias_;
    BrushPtr          current_brush_;
    Rect              visible_size_;
    Matrix3x2         global_transform_;
    mutable Status    status_;

    ComPtr<ITextRenderer>          text_renderer_;
    ComPtr<ID2D1RenderTarget>      render_target_;
    ComPtr<ID2D1DrawingStateBlock> drawing_state_;
};

/** @} */

inline RenderContext::Status::Status()
    : primitives(0)
{
}

inline RenderContext::Status const& RenderContext::GetStatus() const
{
    return status_;
}

inline ComPtr<ID2D1RenderTarget> RenderContext::GetRenderTarget() const
{
    KGE_ASSERT(render_target_);
    return render_target_;
}

inline ComPtr<ITextRenderer> RenderContext::GetTextRenderer() const
{
    KGE_ASSERT(text_renderer_);
    return text_renderer_;
}

inline float RenderContext::GetBrushOpacity() const
{
    return brush_opacity_;
}

inline BrushPtr RenderContext::GetCurrentBrush() const
{
    return current_brush_;
}

inline Matrix3x2 RenderContext::GetGlobalTransform() const
{
    return global_transform_;
}

inline void RenderContext::SetBrushOpacity(float opacity)
{
    brush_opacity_ = opacity;
}

inline void RenderContext::SetGlobalTransform(const Matrix3x2& matrix)
{
    SetGlobalTransform(&matrix);
}

inline void RenderContext::SetCurrentBrush(BrushPtr brush)
{
    current_brush_ = brush;
    if (current_brush_)
    {
        current_brush_->SetOpacity(brush_opacity_);
    }
}

}  // namespace kiwano