#pragma once

#include "core/domain/Project.h"

#include <QPixmap>
#include <QPointF>
#include <QImage>
#include <QPainterPath>
#include <QVector>
#include <QWidget>
#include <QElapsedTimer>

class EditorCanvas final : public QWidget {
    Q_OBJECT
public:
    enum class Tool { Move, Zoom, CreateEntity };
    Q_ENUM(Tool)

    explicit EditorCanvas(QWidget* parent = nullptr);

    void setBackgroundImagePath(const QString& absolutePath);
    QString backgroundImagePath() const { return m_bgAbsPath; }
    void setBackgroundVisible(bool on);
    bool backgroundVisible() const { return m_backgroundVisible; }

    void setDepthMapPath(const QString& absolutePath);
    void setDepthOverlayEnabled(bool on);
    bool depthOverlayEnabled() const { return m_depthOverlayEnabled; }

    void setTool(Tool tool);
    Tool tool() const { return m_tool; }

    void resetView();
    void zoomToFit();

    void setWorldAxesVisible(bool on);
    bool worldAxesVisible() const { return m_worldAxesVisible; }

    void setAxisLabelsVisible(bool on);
    bool axisLabelsVisible() const { return m_axisLabelsVisible; }

    void setGizmoLabelsVisible(bool on);
    bool gizmoLabelsVisible() const { return m_gizmoLabelsVisible; }

    void setGridVisible(bool on);
    bool gridVisible() const { return m_gridVisible; }

    void setCheckerboardVisible(bool on);
    bool checkerboardVisible() const { return m_checkerboardVisible; }

    // 预览呈现：完整背景 + 全部实体（忽略显隐开关），隐藏编辑辅助元素，仅可平移/缩放查看
    void setPresentationPreviewMode(bool on);
    bool presentationPreviewMode() const { return m_presentationPreviewMode; }

    void setEntities(const QVector<core::Project::Entity>& entities, const QString& projectDirAbs);
    void setCurrentFrame(int frame);
    int currentFrame() const { return m_currentFrame; }

    bool isDraggingEntity() const { return m_draggingEntity; }

    void selectEntityById(const QString& id);
    void clearEntitySelection();

    // 与动画求值一致的原点/缩放（用于 K 帧与自动关键帧）
    QPointF selectedAnimatedOriginWorld() const;
    double selectedDepthScale01() const;
    QPointF selectedEntityCentroidWorld() const;
    double selectedDistanceScaleMultiplier() const;
    double selectedUserScale() const;
    double selectedCombinedScale() const;

    enum class DragMode { None, Free, AxisX, AxisY };

signals:
    void hoveredWorldPosChanged(const QPointF& worldPos);
    void hoveredWorldPosDepthChanged(const QPointF& worldPos, int depthZ);
    void selectedEntityChanged(bool hasSelection, const QString& id, int depth, const QPointF& originWorld);
    void requestAddEntity(const core::Project::Entity& entity, const QImage& image);
    void requestMoveEntity(const QString& id, const QPointF& delta);
    void entityDragActiveChanged(bool on);
    void selectedEntityPreviewChanged(const QString& id, int depth, const QPointF& originWorld);

protected:
    void paintEvent(QPaintEvent* e) override;
    void resizeEvent(QResizeEvent* e) override;
    void mousePressEvent(QMouseEvent* e) override;
    void mouseMoveEvent(QMouseEvent* e) override;
    void mouseReleaseEvent(QMouseEvent* e) override;
    void wheelEvent(QWheelEvent* e) override;

private:
    void ensurePixmapLoaded() const;
    void invalidatePixmap();
    void updateCursor();

    QPointF viewToWorld(const QPointF& v) const;
    QPointF worldToView(const QPointF& w) const;
    QRectF worldRectOfBackground() const;

private:
    struct Entity {
        QString id;
        QRectF rect;                 // world 坐标（用于拖拽与约束）
        QVector<QPointF> polygonWorld; // 非空则使用 polygon
        QPainterPath pathWorld;      // polygonWorld 对应的 world 路径（缓存，避免每帧重建）
        QVector<QPointF> cutoutPolygonWorld;
        QColor color;

        // 实体独立信息：
        int depth = 0;          // 0..255，来自划分区域平均深度
        QImage image;           // 抠图后的实体图像（带透明）
        QPointF imageTopLeft;   // image 对应的 world 左上角
        double visualScale = 1.0;  // 实体在 world 坐标下的缩放（用于贴图绘制）
        double userScale = 1.0;    // 与深度距离缩放相乘
        QPointF animatedOriginWorld;
        double animatedDepthScale01 = 0.5;
        // 编辑模式下实体被设为隐藏时：不响应点选且不绘制，除非当前选中（便于树选隐藏实体）
        bool hiddenInEditMode = false;
    };
    int hitTestEntity(const QPointF& worldPos) const;

private:
    QString m_bgAbsPath;
    bool m_backgroundVisible = true;
    mutable QPixmap m_bgPixmap;
    mutable bool m_pixmapDirty = true;
    mutable QImage m_bgImage;          // 原背景（用于抠图/填充）
    mutable QImage m_bgImageCutout;    // 抠图后的背景（实体区域填黑）
    mutable bool m_bgImageDirty = true;
    mutable bool m_bgCutoutDirty = true;

    QString m_depthAbsPath;
    mutable QImage m_depthImage8;
    mutable bool m_depthDirty = true;
    bool m_depthOverlayEnabled = false;
    int m_depthOverlayAlpha = 110;
    bool m_worldAxesVisible = true;
    bool m_axisLabelsVisible = true;
    bool m_gizmoLabelsVisible = true;
    bool m_gridVisible = true;
    bool m_checkerboardVisible = true;
    bool m_presentationPreviewMode = false;

    Tool m_tool = Tool::Move;
    qreal m_scale = 1.0;
    QPointF m_pan; // world 原点对应的 view 坐标偏移（view = world*scale + pan）

    bool m_dragging = false;
    bool m_draggingEntity = false;
    bool m_drawingEntity = false;
    QPointF m_lastMouseView;
    // 拖动以“实体原点 animatedOriginWorld”为基准，避免因缩放导致 rect/topLeft 抖动
    QPointF m_entityDragOffsetOriginWorld;
    QPointF m_entityDragStartAnimatedOrigin;
    // 拖动性能优化：拖动过程中不逐点修改 polygonWorld，而是保留基准形状+增量参数，在 paint 时做变换预览
    bool m_dragPreviewActive = false;
    QVector<QPointF> m_dragPolyBase;
    QPainterPath m_dragPathBase;
    QPointF m_dragImageTopLeftBase;
    QRectF m_dragRectBase;
    QPointF m_dragOriginBase;
    QPointF m_dragDelta;            // 纯平移
    QPointF m_dragCentroidBase;
    double m_dragScaleBase = 1.0;   // 拖动开始时的 visualScale
    double m_dragScaleRatio = 1.0;  // 相对 m_dragScaleBase 的缩放比（由深度重算驱动）
    QElapsedTimer m_previewEmitTimer;
    qint64 m_lastPreviewEmitMs = 0;
    qint64 m_lastDepthScaleRecalcMs = 0;
    int m_selectedEntity = -1;

    DragMode m_dragMode = DragMode::None;
    QPointF m_dragStartMouseWorld;

    QVector<Entity> m_entities;
    QVector<QPointF> m_strokeWorld;

    int m_currentFrame = 0;
};