using System.Collections.Generic;
using System.Linq;
using UnityEngine;

public class SortMarkersExample:MonoBehaviour
{
    public float initialY = 0.1f;
    public float step = 0.02f;

    public GameObject prefab;
    public int countMarkers = 100;

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

        // Generate markers
        // ----------------
        Vector2 tl = OnlineMaps.instance.topLeftPosition;
        Vector2 br = OnlineMaps.instance.bottomRightPosition;

        for (int i = 0; i < countMarkers; i++)
        {
            float lng = Random.Range(tl.x, br.x);
            float lat = Random.Range(br.y, tl.y);

            OnlineMapsControlBase3D.instance.AddMarker3D(lng, lat, prefab);
        }
        // ------------------

        //Initial Sort
        SortMarkers();
    }

    private void SortMarkers()
    {
        IEnumerable<OnlineMapsMarker3D> markers = OnlineMapsControlBase3D.instance.markers3D.Where(m => m.instance.activeSelf).OrderByDescending(m => m, new MarkerComparer());
        float nextStep = initialY;
        foreach (OnlineMapsMarker3D marker in markers)
        {
            Transform child = marker.instance.transform.GetChild(0);
            Vector3 position = child.localPosition;
            position.y = nextStep;
            child.localPosition = position;
            nextStep += step;
        }
    }

    internal class MarkerComparer : IComparer<OnlineMapsMarkerBase>
    {
        public int Compare(OnlineMapsMarkerBase m1, OnlineMapsMarkerBase m2)
        {
            double m1x, m1y, m2x, m2y;
            m1.GetPosition(out m1x, out m1y);
            m2.GetPosition(out m2x, out m2y);

            if (m1y > m2y) return 1;
            if (m1y == m2y)
            {
                if (m1x < m2x) return 1;
                return 0;
            }
            return -1;
        }
    }
}