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

/// <summary>
/// Tracks which rooms have been visited by agents of a specific character type
/// Shared among all agents of the same type to create a collective memory
/// </summary>
public class AIRoomMemory
{
    private string characterType;
    private HashSet<int> visitedRoomIds = new();
    private Dictionary<int, float> roomLastVisitTime = new();

    public AIRoomMemory(string characterType)
    {
        this.characterType = characterType;
    }

    /// <summary>
    /// Marks a room as visited
    /// </summary>
    public void VisitRoom(int roomId)
    {
        if (!visitedRoomIds.Contains(roomId))
        {
            visitedRoomIds.Add(roomId);
        }
        roomLastVisitTime[roomId] = Time.time;
    }

    /// <summary>
    /// Checks if a room has been visited
    /// </summary>
    public bool HasVisited(int roomId)
    {
        return visitedRoomIds.Contains(roomId);
    }

    /// <summary>
    /// Checks if a room has NOT been visited (convenience method)
    /// </summary>
    public bool IsRoomUnvisited(int roomId)
    {
        return !visitedRoomIds.Contains(roomId);
    }

    /// <summary>
    /// Gets all visited room IDs
    /// </summary>
    public HashSet<int> GetVisitedRooms()
    {
        return new HashSet<int>(visitedRoomIds);
    }

    /// <summary>
    /// Gets unvisited rooms from a list of options
    /// </summary>
    public List<MazeRoom> FilterUnvisitedRooms(List<MazeRoom> rooms)
    {
        return rooms.Where(r => !HasVisited(r.Id)).ToList();
    }

    /// <summary>
    /// Gets the character type this memory is for
    /// </summary>
    public string CharacterType => characterType;

    /// <summary>
    /// Gets the number of visited rooms
    /// </summary>
    public int VisitedCount => visitedRoomIds.Count;
}

/// <summary>
/// Global manager for all agent room memories
/// Allows different character types to have separate memory systems
/// </summary>
public class AIRoomMemoryManager : MonoBehaviour
{
    private static AIRoomMemoryManager instance;
    private Dictionary<string, AIRoomMemory> memoryByCharacterType = new();

    void Awake()
    {
        if (instance == null)
        {
            instance = this;
            DontDestroyOnLoad(gameObject);
        }
        else if (instance != this)
        {
            Destroy(gameObject);
        }
    }

    /// <summary>
    /// Gets or creates a room memory for a character type
    /// </summary>
    public static AIRoomMemory GetMemory(string characterType)
    {
        if (instance == null)
        {
            GameObject go = new GameObject("AIRoomMemoryManager");
            instance = go.AddComponent<AIRoomMemoryManager>();
        }

        if (!instance.memoryByCharacterType.ContainsKey(characterType))
        {
            instance.memoryByCharacterType[characterType] = new AIRoomMemory(characterType);
        }

        return instance.memoryByCharacterType[characterType];
    }

    /// <summary>
    /// Clears all memory for a character type (useful for new maze)
    /// </summary>
    public static void ClearMemory(string characterType)
    {
        if (instance != null && instance.memoryByCharacterType.ContainsKey(characterType))
        {
            instance.memoryByCharacterType.Remove(characterType);
        }
    }

    /// <summary>
    /// Clears all memories
    /// </summary>
    public static void ClearAllMemories()
    {
        if (instance != null)
        {
            instance.memoryByCharacterType.Clear();
        }
    }
}