using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.UI;
using XFramework.UIExtensions;

public class DrawLineCtrl : MaskableGraphic
{
    //public List< Vector2> points;
    //public List<bool> colors;
    // public float segments;
    //public float linewidth;

    //非全屏时的修正值  全屏时可为0
    public Vector3 anchorPos = new Vector3(0, 0, 0);

    List<List<UIVertex>> vertexQuadList = new List<List<UIVertex>>();
    List<UIVertex> vertexQuad;
    public float lineWidth = 2;
    Vector3 lastleftPoint;
    Vector3 lastrightPoint;
    Vector3 lastPos= Vector3.zero;

    protected override void OnPopulateMesh(VertexHelper vh)
    {
        vh.Clear();
        for (int i = 0; i < vertexQuadList.Count; i++)
        {
            vh.AddUIVertexQuad(vertexQuadList[i].ToArray());
        }
    }

    void Update()
    {
        if (Input.GetMouseButtonDown(0))
        {
            //  vertexQuadList.Clear();
            if (lastPos == Vector3.zero)
            {
                lastPos = Input.mousePosition - anchorPos;
                lastleftPoint = lastPos - new Vector3(Screen.width / 2, Screen.height / 2, 0) + Vector3.up * lineWidth;
                lastrightPoint = lastPos - new Vector3(Screen.width / 2, Screen.height / 2, 0) - Vector3.up * lineWidth;
            }
            else
            {
                Vector3 newVec = Input.mousePosition - anchorPos - lastPos;
                int colorIndex = Random.Range(0, 2);
                if (colorIndex == 0)
                {
                    color = Color.green;
                }
                else
                    color = Color.red;
                if (newVec.magnitude < 0.1f)
                {
                    return;
                }
                vertexQuad = new List<UIVertex>();
                Vector3 vec = Vector3.Cross(newVec.normalized, Vector3.forward).normalized;
                Vector3 newleftPoint = Input.mousePosition - anchorPos - new Vector3(Screen.width / 2, Screen.height / 2, 0) + vec * lineWidth;
                Vector3 newrightPoint = Input.mousePosition - anchorPos - new Vector3(Screen.width / 2, Screen.height / 2, 0) - vec * lineWidth;
                UIVertex uIVertex = new UIVertex();
                uIVertex.position = lastleftPoint;
                uIVertex.color = color;
                vertexQuad.Add(uIVertex);
                UIVertex uIVertex1 = new UIVertex();
                uIVertex1.position = lastrightPoint;
                uIVertex1.color = color;
                vertexQuad.Add(uIVertex1);
                UIVertex uIVertex3 = new UIVertex();
                uIVertex3.position = newrightPoint;
                uIVertex3.color = color;
                vertexQuad.Add(uIVertex3);
                UIVertex uIVertex2 = new UIVertex();
                uIVertex2.position = newleftPoint;
                uIVertex2.color = color;
                vertexQuad.Add(uIVertex2);
                lastleftPoint = newleftPoint;
                lastrightPoint = newrightPoint;
                vertexQuadList.Add(vertexQuad);
                lastPos = Input.mousePosition - anchorPos;
                SetVerticesDirty();
            }
        }
    

        if (Input.GetMouseButtonDown(1))
        {
            lastPos = Vector3.zero;
            vertexQuadList.Clear();
            SetVerticesDirty();
        }
    }
}