#define Graph_And_Chart_PRO
using ChartAndGraph;
using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

[RequireComponent(typeof(CustomChartPointer))]
public class GraphRectZoom : MonoBehaviour
{
    public RectTransform Marker;
    public int MinMarkerPixels = 20;
    CustomChartPointer mPointer;
    RectTransform mRect;
    bool mIsDown = false;
    Vector2 mStart;
    bool mIsZoomed = false;
    bool mIsUp = true;
    // Start is called before the first frame update
    void Start()
    {
        mRect = GetComponent<RectTransform>();
        mPointer = GetComponent<CustomChartPointer>();
        Marker.gameObject.SetActive(false);
    }
    void OnMarkerStart()
    {
        mIsDown = true;
        mStart = mPointer.ScreenPosition;
        Marker.gameObject.SetActive(true);
    }
    void OnMarkerMove()
    {
        Vector3 end = mPointer.ScreenPosition;
        Vector3 min = new Vector3(Mathf.Min(mStart.x, end.x), Mathf.Min(mStart.y, end.y));
        Vector3 max = new Vector3(Mathf.Max(mStart.x, end.x), Mathf.Max(mStart.y, end.y));
        Marker.position = min;
        Marker.sizeDelta = max - min;
    }
    void OnMarkerEnd()
    {
        mIsDown = false;
        Marker.gameObject.SetActive(false);
    }
    bool CheckBounds()
    {
        Vector2 v = mPointer.ScreenPosition - mStart;
        if (Math.Abs(v.x) < MinMarkerPixels || Math.Abs(v.y) < MinMarkerPixels)
            return false;
        return true;
    }
    void SetGraphZoom()
    {
        if (CheckBounds() == false)
            return;
        var graph = GetComponent<GraphChart>();
        double x1, y1;
        double x2, y2;
        if(graph.PointToClient(mStart,out x1,out y1))
        {
            if(graph.PointToClient(mPointer.ScreenPosition,out x2,out y2))
            {
                mIsZoomed = true;
                graph.DataSource.AutomaticHorizontalView = false;
                graph.DataSource.AutomaticVerticallView = false;

                DoubleVector2 min = new DoubleVector2(Math.Min(x1, x2), Math.Min(y1, y2));
                DoubleVector2 max = new DoubleVector2(Math.Max(x1, x2), Math.Max(y1, y2));
                graph.HorizontalScrolling = min.x;
                graph.VerticalScrolling = min.y;
                graph.DataSource.HorizontalViewSize = max.x - min.x;
                graph.DataSource.VerticalViewSize = max.y - min.y;
                graph.DataSource.HorizontalViewOrigin = 0;
                graph.DataSource.VerticalViewOrigin = 0;

            }
        }
    }
    // Update is called once per frame
    void Update()
    {
        if(mIsZoomed && mPointer.IsMouseDown)
        {
            mIsZoomed = false;
            var graph = GetComponent<GraphChart>();
            graph.DataSource.AutomaticHorizontalView = true;
            graph.DataSource.AutomaticVerticallView = true;
            graph.HorizontalScrolling = 0;
            graph.VerticalScrolling = 0;
            mIsUp = false;
            return;
        }
        if (mIsUp == false && mPointer.IsMouseDown)
            return;
        mIsUp = true;
        Vector2 pointerPos = mPointer.ScreenPosition;

        if (mIsDown == false)
        {
            if (mPointer.IsMouseDown == true) // the mouse is clicked in this frame
            {
                OnMarkerStart();    //start the marker
                OnMarkerMove();
            }

        }
        else
        {
            
            if (mPointer.IsMouseDown == false) // the mouse is up this frame
            {
                OnMarkerEnd(); // end the marker
                if (mPointer.IsOut == false)
                    SetGraphZoom(); // set graph zoom

            }
            else
            {
                OnMarkerMove(); // the mouse is being held
            }
        }
    }
}