using System.Collections.Generic;
using UnityEngine;

public class CustomUGUIMarkerEngine : MonoBehaviour 
{
    private static CustomUGUIMarkerEngine _instance;
    private static List<CustomUGUIMarker> markers;

    public RectTransform markerContainer;
    public GameObject markerPrefab;

    private GameObject container;

    public static CustomUGUIMarkerEngine instance
    {
        get { return _instance; }
    }

    public static void AddMarker(Vector2 position, string text)
    {
        _instance._AddMarker(position, text);
    }

    private void _AddMarker(Vector2 position, string text)
    {
        GameObject markerGameObject = Instantiate(markerPrefab) as GameObject;
        (markerGameObject.transform as RectTransform).SetParent(markerContainer);
        CustomUGUIMarker marker = markerGameObject.GetComponent<CustomUGUIMarker>();
        marker.text = text;
        marker.position = position;
        markers.Add(marker);
        UpdateMarker(marker);
    }

    private void OnEnable()
    {
        _instance = this;
        markers = new List<CustomUGUIMarker>();
    }

	private void Start () 
    {
	    OnlineMaps.instance.OnChangePosition += UpdateMarkers;
        OnlineMaps.instance.OnChangeZoom += UpdateMarkers;

	    if (OnlineMapsControlBase.instance is OnlineMapsControlBase3D)
	        OnlineMapsControlBase3D.instance.OnCameraControl += UpdateMarkers;

        AddMarker(new Vector2(), "12");
    }

    private void UpdateMarkers()
    {
        foreach (CustomUGUIMarker marker in markers) UpdateMarker(marker);
    }

    private void UpdateMarker(CustomUGUIMarker marker)
    {
        OnlineMaps api = OnlineMaps.instance;
        Vector2 pos = marker.position;
        Vector2 tl = api.topLeftPosition;
        Vector2 br = api.bottomRightPosition;

        if (pos.x < tl.x || pos.x > br.x || pos.y < br.y || pos.y > tl.y)
        {
            marker.gameObject.SetActive(false);
            return;
        }

        Vector2 screenPosition = OnlineMapsControlBase.instance.GetScreenPosition(pos);

        RectTransform markerRectTransform = marker.transform as RectTransform;

        if (!marker.gameObject.activeSelf)
        {
            marker.gameObject.SetActive(true);
        }

        screenPosition.y += markerRectTransform.rect.height / 2;

        Vector2 point;
        RectTransformUtility.ScreenPointToLocalPointInRectangle(markerRectTransform.parent as RectTransform, screenPosition, null, out point);
        markerRectTransform.localPosition = point;
    }
}