using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;

namespace BSO
{
    public struct EntityInfo
    {
        public int Slot;
        public nint Ptr;
        public string Class;
        public Vec3 Pos;
    }

    /// <summary>Alle Entities der Szene (VisBaseEntity_cl) mit Klassenname und Position.</summary>
    public static unsafe class Entities
    {
        public static List<EntityInfo> Scan()
        {
            var list = new List<EntityInfo>();
            if (!Vision.TryGetEntities(out nint* data, out int count)) return list;
            for (int i = 0; i < count; i++)
            {
                nint e = data[i];
                if (e == 0) continue;
                string cls = Rtti.ClassName(e);
                if (cls == null) continue; // kein gueltiges Objekt - lieber nicht anfassen
                list.Add(new EntityInfo { Slot = i, Ptr = e, Class = cls, Pos = Vision.GetPosition(e) });
            }
            return list;
        }

        /// <summary>Platz einer Entity in der Tabelle, -1 = nicht (mehr) da.</summary>
        public static int SlotOf(nint ptr)
        {
            if (ptr == 0 || !Vision.TryGetEntities(out nint* data, out int count)) return -1;
            for (int i = 0; i < count; i++) if (data[i] == ptr) return i;
            return -1;
        }

        /// <summary>Steht in Platz slot noch dasselbe Objekt? Dann lebt es noch und darf gelesen werden.</summary>
        public static bool StillThere(int slot, nint ptr)
        {
            return Vision.TryGetEntities(out nint* data, out int count) && slot < count && data[slot] == ptr;
        }

        /// <summary>Diagnose (F10): alle Entities nach BSO\entities.txt, naechste zur Kamera zuerst.</summary>
        public static string Dump(Vec3 camera)
        {
            var list = Scan();
            var sb = new StringBuilder();
            sb.AppendLine($"BSO {Bootstrap.ModVersion} - {list.Count} Entities, Kamera bei {camera}");
            sb.AppendLine();
            sb.AppendLine("Klassen:");
            foreach (var g in list.GroupBy(e => e.Class).OrderByDescending(g => g.Count()))
                sb.AppendLine($"  {g.Count(),5}  {g.Key}");
            sb.AppendLine();
            sb.AppendLine("Platz   Abstand  Klasse                              Position");
            foreach (var e in list.OrderBy(e => (e.Pos - camera).Length))
                sb.AppendLine($"{e.Slot,5}  {(e.Pos - camera).Length,8:0}  {e.Class,-34}  {e.Pos}");

            string file = Path.Combine(Bootstrap.Folder, "entities.txt");
            File.WriteAllText(file, sb.ToString());
            Bootstrap.Log($"{list.Count} Entities nach {file} geschrieben");
            return file;
        }
    }
}