using System;
using System.Collections;
using System.Collections.Generic;
using System.IO;
using HK.Keyboard;
// using TalesFromTheRift;
using TMPro;
using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.UI;

public class DrawOnTexture : MonoBehaviour
{
    public GameObject[] boardObject;

    public void OpenDraw()
    {
        foreach (GameObject obj in boardObject)
            obj.SetActive(true);
    }

    public void CloseDraw()
    {
        foreach (GameObject obj in boardObject)
            obj.SetActive(false);
    }


    public Keyboard keyboard;
    private LineRenderer lineRender;

    // Start is called before the first frame update
    void Start()
    {
        //lineRender = GetComponent<LineRenderer>();
    }

    private void Awake()
    {
        canvas = GetComponentInParent<Canvas>();
    }

    List<Vector3> currentPos = new List<Vector3>();
    List<LineRenderer> strokes = new List<LineRenderer>();

    List<Vector3> fingerPos = new List<Vector3>();

    //public TextMeshProUGUI text;

    private void Update()
    {
        var go = GetUI(canvas.gameObject);
        if (go == null || go.name != "ShowStrokes")
        {
            isCanStartDrawing = false;
            return;
        }

        isCanStartDrawing = true;

        if (IsDrawing)
        {
            Vector3 currentFingerPos = Input.mousePosition;
            if (Input.touchCount > 0)
            {
                Touch touch = Input.GetTouch(0);
                //text.text = touch.position.ToString();
                currentFingerPos = touch.position;
            }

            currentFingerPos.z = 10;

            if (fingerPos.Count > 0)
            {
                Vector3 previousPos = fingerPos[fingerPos.Count - 1];
                if (Vector3.Distance(currentFingerPos, previousPos) > 5)
                {
                    Vector3 worldPos = Camera.main.ScreenToWorldPoint(currentFingerPos);
                    worldPos.z = 0;
                    currentPos.Add(worldPos);
                    fingerPos.Add(currentFingerPos);
                    lineRender.positionCount = currentPos.Count;
                    lineRender.SetPositions(currentPos.ToArray());
                }
            }
            else
            {
                Vector3 worldPos = Camera.main.ScreenToWorldPoint(currentFingerPos);
                worldPos.z = 0;
                currentPos.Add(worldPos);
                fingerPos.Add(currentFingerPos);
                lineRender.positionCount = currentPos.Count;
                lineRender.SetPositions(currentPos.ToArray());
            }

            resetTimer = TIMEBEFORERESET;
        }
        else
        {
            resetTimer -= Time.deltaTime;
            if (resetTimer <= 0 && fingerPos.Count > 0)
            {
                //Texture2D tex = ToTexture2D(renderTex);
                //SaveTex(tex);
                MyIMEApi.instance.SendApi(ToJsonData(), this);


                //currentPos.Clear();
                fingerPos.Clear();
            }
        }
    }

    public void DoneLoadingDestroyStrokes(string str)
    {
        Debug.Log("{str}");
        keyboard.AddHandWritingBoardKey(str);
        foreach (LineRenderer stroke in strokes)
            Destroy(stroke.gameObject);
        strokes.Clear();
    }

    private const float TIMEBEFORERESET = 1f;
    private float resetTimer = 1f;


    private bool IsDrawing = false;
    public LineRenderer strokePrefab;
    public Transform strokePrefabParent;

    public void StartDrawing()
    {
        if (IsDrawing)
            return;
        if (!isCanStartDrawing)
            return;

        lineRender = Instantiate(strokePrefab, strokePrefabParent);
        currentPos.Clear();
        strokes.Add(lineRender);
        IsDrawing = true;
    }

    bool isCanStartDrawing = false;
    Canvas canvas;

    /// <summary>
    /// 获取鼠标停留处UI
    /// </summary>
    public static GameObject GetUI(GameObject canvas)
    {
        if (canvas.GetComponent<GraphicRaycaster>() == null) return null;
        PointerEventData pointerEventData = new PointerEventData(EventSystem.current);
        pointerEventData.position = Input.mousePosition;
        GraphicRaycaster gr = canvas.GetComponent<GraphicRaycaster>();
        List<RaycastResult> results = new List<RaycastResult>();
        gr.Raycast(pointerEventData, results);
        if (results.Count != 0)
        {
            return results[0].gameObject;
        }

        return null;
    }

    public void StopDrawing()
    {
        if (!IsDrawing)
            return;
        IsDrawing = false;
    }

    string ToJsonData()
    {
        string x = "";
        string y = "";
        for (int i = 0; i < fingerPos.Count; i++)
        {
            Vector3 offsetPos = fingerPos[i] - new Vector3(0, 199);
            offsetPos.y = 460 - offsetPos.y;
            x += ((int)offsetPos.x).ToString();
            if (i < fingerPos.Count - 1)
                x += ",";
            y += ((int)offsetPos.y).ToString();
            if (i < fingerPos.Count - 1)
                y += ",";
        }


        string json = "[";
        json += x;
        json += "],";
        json += "[";
        json += y;
        json += "],";

        Debug.Log(json);
        return json;
    }


    public RenderTexture renderTex;

    void SaveTex(Texture2D texture)
    {
        //then Save To Disk as PNG
        byte[] bytes = texture.EncodeToPNG();
        var dirPath = Application.dataPath + "SaveImages/";
        if (!Directory.Exists(dirPath))
        {
            Directory.CreateDirectory(dirPath);
        }

        File.WriteAllBytes(dirPath + "Image" + ".png", bytes);
    }

    Texture2D ToTexture2D(RenderTexture rTex)
    {
        RenderTexture currentActiveRT = RenderTexture.active;
        Texture2D tex = new Texture2D(rTex.width, rTex.height, TextureFormat.ARGB32, false);
        RenderTexture.active = rTex;
        tex.ReadPixels(new Rect(0, 0, rTex.width, rTex.height), 0, 0);
        tex.Apply();
        RenderTexture.active = currentActiveRT;
        return tex;
    }
}