using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Shapes;

namespace XP.ImageProcessing.RoiControl.Models
{
    /// <summary>一次点点距测量的所有视觉元素</summary>
    public class MeasureGroup
    {
        // 保留原有圆点属性以兼容其他代码
        public Ellipse Dot1 { get; set; }
        public Ellipse Dot2 { get; set; }
        
        // 新增：垂直线段（替代圆点的视觉表现）
        public Line PerpLine1 { get; set; }
        public Line PerpLine2 { get; set; }
        
        public Line Line { get; set; }
        public TextBlock Label { get; set; }
        public Point P1 { get; set; }
        public Point P2 { get; set; }
        
        /// <summary>垂直线段长度（像素）</summary>
        public double PerpLineLength { get; set; } = 10.0;

        public double Distance
        {
            get
            {
                double dx = P2.X - P1.X, dy = P2.Y - P1.Y;
                return Math.Sqrt(dx * dx + dy * dy);
            }
        }

        public void UpdateLine()
        {
            Line.X1 = P1.X; Line.Y1 = P1.Y;
            Line.X2 = P2.X; Line.Y2 = P2.Y;
            Line.Visibility = Visibility.Visible;
            
            // 更新垂直线段位置
            UpdatePerpLines();
        }

        /// <summary>更新两条垂直线段的位置</summary>
        public void UpdatePerpLines()
        {
            if (PerpLine1 == null || PerpLine2 == null) return;
            
            // 计算两点连线的方向向量
            double dx = P2.X - P1.X;
            double dy = P2.Y - P1.Y;
            double len = Math.Sqrt(dx * dx + dy * dy);
            
            if (len < 0.001) return; // 避免除零
            
            // 归一化方向向量
            double ux = dx / len;
            double uy = dy / len;
            
            // 垂直方向向量 (-uy, ux)
            double vx = -uy;
            double vy = ux;
            
            // P1处的垂直线段
            double halfLen1 = PerpLineLength / 2;
            PerpLine1.X1 = P1.X + vx * halfLen1;
            PerpLine1.Y1 = P1.Y + vy * halfLen1;
            PerpLine1.X2 = P1.X - vx * halfLen1;
            PerpLine1.Y2 = P1.Y - vy * halfLen1;
            PerpLine1.Visibility = Visibility.Visible;
            
            // P2处的垂直线段
            double halfLen2 = PerpLineLength / 2;
            PerpLine2.X1 = P2.X + vx * halfLen2;
            PerpLine2.Y1 = P2.Y + vy * halfLen2;
            PerpLine2.X2 = P2.X - vx * halfLen2;
            PerpLine2.Y2 = P2.Y - vy * halfLen2;
            PerpLine2.Visibility = Visibility.Visible;
        }

        public void UpdateLabel(string distanceText = null)
        {
            Label.Text = (Index > 0 ? $"#{Index} " : "") + (distanceText ?? $"{Distance:F2} px");
            Canvas.SetLeft(Label, (P1.X + P2.X) / 2 + 8);
            Canvas.SetTop(Label, (P1.Y + P2.Y) / 2 - 18);
            Label.Visibility = Visibility.Visible;
        }

        public int Index { get; set; }
    }
}