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

[ExecuteAlways]
public class Node : MonoBehaviour
{
    [Range(-1, 1)]
    [SerializeField]
    public int Owner = -1;
    public Material materialOwnerSelf, materialOwnerOther, materialOwnerNone, materialHover;

    public List<Node> connected;

    public bool hovered;

    void Awake()
    {
        UpdateColor();
    }

    // Start is called once before the first execution of Update after the MonoBehaviour is created
    void Start()
    {
    }

    // Update is called once per frame
    void Update()
    {


        if (Input.GetMouseButtonDown(0) && hovered)
        {
            var count = CycleFinder.FindLargestCycleAmongNeighbors(this);

            Debug.Log($"Largest Nacho: {count.Count}");
        }


        UpdateColor();
        UpdateTransform();
    }

    private void OnValidate()
    {
        UpdateColor();
        UpdateTransform();
    }

    private void OnDestroy()
    {
        GameManager gm = FindFirstObjectByType<GameManager>();

        List<GameManager.Connection> looseConnections = gm.connections.FindAll(c => c.nodeA == this || c.nodeB == this);

        foreach (GameManager.Connection c in looseConnections)
        {
            DestroyImmediate(c.lineRenderer.gameObject);
            gm.connections.Remove(c);
        }

        gm.FetchAllNodes();
    }

    public void UpdateTransform()
    {
        transform.localPosition = transform.localPosition.normalized * 20f;
        if (transform.position != Vector3.zero)
            transform.forward = transform.position;
    }

    public void UpdateColor()
    {
        if (hovered)
        {
            transform.GetChild(0).GetComponent<Renderer>().sharedMaterial = materialHover;
        }
        else
        {
            switch (Owner)
            {
                case -1: transform.GetChild(0).GetComponent<Renderer>().sharedMaterial = materialOwnerNone; break;
                case 0: transform.GetChild(0).GetComponent<Renderer>().sharedMaterial = materialOwnerSelf; break;
                case 1: transform.GetChild(0).GetComponent<Renderer>().sharedMaterial = materialOwnerOther; break;
            }
        }

        hovered = false;
    }

}


public class CycleFinder
{
    private HashSet<Node> allowedNodes;
    private List<Node> bestCycle;
    private Node centerNode;

    public CycleFinder(Node center)
    {
        centerNode = center;
        allowedNodes = new HashSet<Node>(center.connected);
        bestCycle = new List<Node>();
    }

    public static List<Node> FindLargestCycleAmongNeighbors(Node center)
    {
        var finder = new CycleFinder(center);
        return finder.FindBestCycle();
    }

    private List<Node> FindBestCycle()
    {
        // Versuche von jedem Nachbarknoten aus einen Zyklus zu finden
        foreach (var startNode in allowedNodes)
        {
            var visited = new HashSet<Node>();
            var currentPath = new List<Node>();

            SearchForCycles(startNode, startNode, visited, currentPath);
        }

        return bestCycle;
    }

    private void SearchForCycles(Node startNode, Node currentNode, HashSet<Node> visited, List<Node> path)
    {
        // Aktuellen Knoten zum Pfad hinzufugen
        path.Add(currentNode);
        visited.Add(currentNode);

        // Durchsuche alle Verbindungen des aktuellen Knotens
        foreach (var neighbor in currentNode.connected)
        {
            // Nur Nachbarn des Zentralknotens sind erlaubt
            if (!allowedNodes.Contains(neighbor))
                continue;

            // Wenn wir zum Startknoten zuruckgekehrt sind und mindestens 3 Knoten im Pfad haben
            if (neighbor == startNode && path.Count >= 3)
            {
                // Geschlossenen Zyklus gefunden - prufe ob er besser ist
                if (path.Count > bestCycle.Count)
                {
                    bestCycle = new List<Node>(path);
                }
            }
            // Wenn der Knoten noch nicht besucht wurde, setze die Suche fort
            else if (!visited.Contains(neighbor))
            {
                SearchForCycles(startNode, neighbor, new HashSet<Node>(visited), new List<Node>(path));
            }
        }
    }
}