#pragma once

#include "Item.h"
#include "SpatialIndex.h"

namespace NItem
{

class CItemMeasure
	: public CItem
{
public:
	CItemMeasure(CSigmaDoc* ppDoc);
	~CItemMeasure();

	void 	OnLButtonDblClk(UINT nFlags, CPoint point) override;

	void 	OnLButtonDown(CDC* pDC, UINT nFlags, CPoint point, int vk) override;

	void 	OnLButtonUp(CDC* pDC, UINT nFlags, CPoint point, int vk) override;

	int		OnMouseMove(CDC* pDC, UINT nFlags, CPoint point) override;

	void 	OnMouseMoveStatus(CDC* pDC, UINT nFlags, CPoint point, BYTE*& destBuffer, int& destLen) override;

	BOOL 	OnKeyDown(UINT nChar, UINT nRepCnt, UINT nFlags) override;

	BOOL 	OnKeyUp(UINT nChar, UINT nRepCnt, UINT nFlags) override;

	BOOL 	OnSetCursor(CWnd* pWnd, UINT nHitTest, UINT message) override;

	void 	OnDraw(CXyDC* pDC) override;

	void 	OnDraw(CXyDC* pXyDC, CDC* pDC) override;

	void 	DrawAssistant(CDC* pDC, int mouseX, int mouseY) override;

	void 	OnOK(void) override;
	 
	void 	OnCancel(void) override;

	CString GetCurrentInfo() const;

	/**
	 * 开启吸附功能
	 * 
	 */
	void EnableSnap();

	/**
	 * 关闭吸附功能
	 * 
	 */
	void DisableSnap();

	bool IsSnapEnabled() const;

private:
	void DrawCross(Gdiplus::Graphics& graphics, Gdiplus::PointF center, int length, const Gdiplus::Pen& pen) const;

	/**
	 * 将真实坐标转换为屏幕坐标
	 * 
	 * \param realPoint	真实坐标
	 * \return			屏幕坐标
	 */
	CPoint GetScreenPoint(const CPoint2D& realPoint) const;

	/**
	 * 获取吸附点
	 * 
	 * \param point 当前光标位置，屏幕坐标
	 * \return		如果吸附点存在，返回屏幕坐标，否则返回 std::nullopt;
	 */
	std::optional<CPoint2D> GetSnapPoint(const CPoint& point) const;

	/**
	 * 当前状态
	 */
	enum class MeasureState { Idle, SelectingStart, SelectingEnd };


	bool m_isSnapEnabled = true;
	// 吸附的正方形范围，这个是屏幕坐标系，不是实际坐标系
	double m_snapRange = 30.0;

	MeasureState m_state = MeasureState::Idle;
	CPoint2D m_startPoint;
	CPoint2D m_endPoint;
	CPoint2D m_prevPoint;
	COLORREF m_penColor = RGB(0, 0, 0);
	int m_penWidth = 1; // 线宽
	std::unique_ptr<CSpatialIndex> m_pSpatialIndex;
};

}