using System.Collections.Generic;
using UnityEngine;

public class OneMillionMarkers : MonoBehaviour
{
    private const int countMarkers = 1000000;

    private List<OnlineMapsMarker>[] markers;
    private OnlineMaps map;
    private int pitx;
    private int pity;
    private int pibx;
    private int piby;

    private void OnChangePosition()
    {
        double tlx, tly, brx, bry;
        map.GetTopLeftPosition(out tlx, out tly);
        map.GetBottomRightPosition(out brx, out bry);

        if (tlx > brx) brx += 360;

        int itx = (int)((tlx + 180) / 10);
        int ity = (int)((bry + 90) / 10);
        int ibx = (int)((brx + 180) / 10) + 1;
        int iby = (int)((tly + 90) / 10) + 1;

        if (itx != pitx || ity != pity || pibx != ibx || piby != iby) UpdateMarkers();
    }

    private void GenerateMarkers()
    {
        markers = new List<OnlineMapsMarker>[648]; // 36 * 18

        for (int i = 0; i < countMarkers; i++)
        {
            OnlineMapsMarker marker = new OnlineMapsMarker();
            double longitude = Random.Range(-180f, 180f);
            double latitude = Random.Range(-90f, 90f);
            marker.SetPosition(longitude, latitude);
            marker.label = "Marker " + i;
            marker.Init();

            int mx = (int) ((longitude + 180) / 10);
            int my = (int) ((latitude + 90) / 10);
            int index = mx * 18 + my;

            if (markers[index] == null) markers[index] = new List<OnlineMapsMarker>(32);
            else if (markers[index].Count == markers[index].Capacity) markers[index].Capacity += 32;
            markers[index].Add(marker);
        }
    }

    private void Start()
    {
        map = OnlineMaps.instance;

        GenerateMarkers();
        UpdateMarkers();
        map.OnChangePosition += OnChangePosition;
        map.OnChangeZoom += UpdateMarkers;
    }

    private void UpdateMarkers()
    {
        double tlx, tly, brx, bry;
        map.GetTopLeftPosition(out tlx, out tly);
        map.GetBottomRightPosition(out brx, out bry);

        if (tlx > brx) brx += 360;

        List<OnlineMapsMarker> ms = new List<OnlineMapsMarker>();
        int itx = (int) ((tlx + 180) / 10);
        int ity = (int) ((bry + 90) / 10);
        int ibx = (int) ((brx + 180) / 10) + 1;
        int iby = (int) ((tly + 90) / 10) + 1;

        for (int x = itx; x < ibx; x++)
        {
            int cx = x;
            if (cx >= 36) cx -= 36;
            cx *= 18;

            for (int y = ity; y < iby; y++)
            {
                ms.AddRange(markers[cx + y]);
            }
        }

        OnlineMaps.instance.markers = ms.ToArray();

        pitx = itx;
        pity = ity;
        pibx = ibx;
        piby = iby;
    }
}