using System;
using Gameplay;
using Framework;
using Gameplay.Unit;
using Gameplay.Level;
using System.Collections.Generic;

public static class NearestSearchUtils
{
    public static int FindNearestIndex<T>(GameUnit owner, List<T> list, Func<T, int> getCellIndexFunc)
    {
        try
        {
            var map = LevelManager.Instance.CurrentLevel?.Map;
            if (owner == null || map == null || list == null || list.Count == 0)
                return Constants.INVALID_ID;

            var ownerCellIndex = owner.transData?.cellIndex ?? Constants.INVALID_ID;
            if (ownerCellIndex == Constants.INVALID_ID)
                return Constants.INVALID_ID;

            var nearestIndex = 0;
            var minDistance = int.MaxValue;

            for (var i = 0; i < list.Count; i++)
            {
                var targetCellIndex = getCellIndexFunc(list[i]);
                if (targetCellIndex == Constants.INVALID_ID) continue;

                var distance = MapUtils.Distance(map, ownerCellIndex, targetCellIndex);
                if (distance >= minDistance) continue;
                minDistance = distance;
                nearestIndex = i;
            }

            return nearestIndex;
        }
        catch (Exception e)
        {
            DebugUtil.LogError("NearestSearchUtils.FindNearestIndex error: {0}", e);
            return 0;
        }
    }
}