#pragma once
#include "vde/core/point.h"
#include <vector>

namespace vde::core {

class Polygon2D {
public:
    Polygon2D() = default;
    explicit Polygon2D(std::vector<Point2D> vertices) : vertices_(std::move(vertices)) {}

    [[nodiscard]] const std::vector<Point2D>& vertices() const { return vertices_; }
    [[nodiscard]] size_t size() const { return vertices_.size(); }
    [[nodiscard]] bool empty() const { return vertices_.empty(); }

    /// Signed area (positive = CCW)
    [[nodiscard]] double signed_area() const;

    /// Absolute area
    [[nodiscard]] double area() const { return std::abs(signed_area()); }

    /// Point-in-polygon test (ray casting)
    [[nodiscard]] bool contains(const Point2D& p) const;

    /// Is the polygon counter-clockwise?
    [[nodiscard]] bool is_ccw() const { return signed_area() > 0; }

private:
    std::vector<Point2D> vertices_;
};

}  // namespace vde::core