using System.Collections.Generic;
using OTGIntegrated.Save;
using OTGIntegrated.Stats;
using UnityEngine;
using UnityEngine.UI;

namespace OTGIntegrated.Talents
{
    public sealed class TalentTreeUI : MonoBehaviour
    {
        public GameObject panelRoot;
        public RectTransform nodesRoot;
        public RectTransform lineRoot;
        public TalentTooltipUI tooltip;
        public Text titleText;
        public Text pointsText;
        public Text statsText;
        public Button saveButton;
        public Button loadButton;
        public Button resetButton;
        public Button closeButton;
        public Font uiFont;

        private TalentManager talentManager;
        private PlayerStats playerStats;
        private readonly List<TalentNodeUI> nodes = new List<TalentNodeUI>();
        private readonly List<GameObject> spawnedLines = new List<GameObject>();

        public void Initialize(TalentManager manager, PlayerStats stats)
        {
            talentManager = manager;
            playerStats = stats;

            if (talentManager != null)
            {
                talentManager.OnTalentStateChanged -= Refresh;
                talentManager.OnTalentStateChanged += Refresh;
            }

            if (playerStats != null)
            {
                playerStats.OnStatsChanged -= Refresh;
                playerStats.OnStatsChanged += Refresh;
            }

            if (saveButton != null) saveButton.onClick.AddListener(() => FindObjectOfType<SaveSystem>()?.Save());
            if (loadButton != null) loadButton.onClick.AddListener(() => FindObjectOfType<SaveSystem>()?.Load());
            if (resetButton != null) resetButton.onClick.AddListener(() => FindObjectOfType<SaveSystem>()?.ResetSave());
            if (closeButton != null) closeButton.onClick.AddListener(() => FindObjectOfType<OTGIntegrated.UI.UIManager>()?.CloseCurrentWindow());

            BuildTree();
            Refresh();
        }

        private void OnEnable()
        {
            Refresh();
        }

        private void OnDestroy()
        {
            if (talentManager != null)
            {
                talentManager.OnTalentStateChanged -= Refresh;
            }

            if (playerStats != null)
            {
                playerStats.OnStatsChanged -= Refresh;
            }
        }

        public void BuildTree()
        {
            ClearTree();
            if (talentManager == null || nodesRoot == null)
            {
                return;
            }

            Dictionary<TalentData, TalentNodeUI> lookup = new Dictionary<TalentData, TalentNodeUI>();
            for (int i = 0; i < talentManager.allTalents.Count; i++)
            {
                TalentData talent = talentManager.allTalents[i];
                if (talent == null)
                {
                    continue;
                }

                TalentNodeUI node = CreateNode(talent);
                nodes.Add(node);
                lookup[talent] = node;
            }

            for (int i = 0; i < talentManager.allTalents.Count; i++)
            {
                TalentData talent = talentManager.allTalents[i];
                if (talent == null || talent.prerequisites == null || !lookup.TryGetValue(talent, out TalentNodeUI node))
                {
                    continue;
                }

                for (int p = 0; p < talent.prerequisites.Length; p++)
                {
                    TalentData prerequisite = talent.prerequisites[p];
                    if (prerequisite != null && lookup.TryGetValue(prerequisite, out TalentNodeUI prerequisiteNode))
                    {
                        CreateLine(prerequisiteNode.GetComponent<RectTransform>().anchoredPosition, node.GetComponent<RectTransform>().anchoredPosition);
                    }
                }
            }
        }

        public void Refresh()
        {
            if (titleText != null)
            {
                titleText.text = "Дерево талантов";
            }

            if (pointsText != null)
            {
                int points = talentManager != null ? talentManager.availableTalentPoints : 0;
                pointsText.text = $"Очки талантов: {points}";
            }

            if (statsText != null)
            {
                statsText.text = playerStats == null
                    ? "Характеристики недоступны"
                    : $"Характеристики\nHP: {Mathf.RoundToInt(playerStats.CurrentHealth)} / {Mathf.RoundToInt(playerStats.MaxHealth)}\nMana: {Mathf.RoundToInt(playerStats.CurrentMana)} / {Mathf.RoundToInt(playerStats.MaxMana)}\nDamage: {playerStats.Damage:0.#}\nMove: {playerStats.MoveSpeed:0.#}\nCrit: {playerStats.CriticalChance:P0}\nCooldown: {playerStats.CooldownReduction:P0}";
            }

            for (int i = 0; i < nodes.Count; i++)
            {
                if (nodes[i] != null)
                {
                    nodes[i].Refresh();
                }
            }
        }

        private TalentNodeUI CreateNode(TalentData talent)
        {
            GameObject root = new GameObject(talent.displayName, typeof(RectTransform), typeof(Image), typeof(Button), typeof(TalentNodeUI));
            root.transform.SetParent(nodesRoot, false);
            RectTransform rect = root.GetComponent<RectTransform>();
            rect.sizeDelta = new Vector2(160f, 76f);
            rect.anchorMin = new Vector2(0.5f, 0.5f);
            rect.anchorMax = new Vector2(0.5f, 0.5f);
            rect.anchoredPosition = talent.treePosition;

            Text title = CreateText(root.transform, "Title", talent.displayName, 15, TextAnchor.MiddleCenter);
            title.rectTransform.anchorMin = new Vector2(0.08f, 0.25f);
            title.rectTransform.anchorMax = new Vector2(0.92f, 0.9f);
            title.rectTransform.offsetMin = Vector2.zero;
            title.rectTransform.offsetMax = Vector2.zero;

            Text cost = CreateText(root.transform, "Cost", talent.cost.ToString(), 14, TextAnchor.MiddleCenter);
            cost.rectTransform.anchorMin = new Vector2(0.78f, 0.02f);
            cost.rectTransform.anchorMax = new Vector2(0.98f, 0.3f);
            cost.rectTransform.offsetMin = Vector2.zero;
            cost.rectTransform.offsetMax = Vector2.zero;

            TalentNodeUI node = root.GetComponent<TalentNodeUI>();
            node.background = root.GetComponent<Image>();
            node.button = root.GetComponent<Button>();
            node.titleText = title;
            node.costText = cost;
            node.Initialize(talent, talentManager, tooltip, uiFont);
            return node;
        }

        private void CreateLine(Vector2 start, Vector2 end)
        {
            if (lineRoot == null)
            {
                return;
            }

            GameObject line = new GameObject("TalentLine", typeof(RectTransform), typeof(Image));
            line.transform.SetParent(lineRoot, false);
            spawnedLines.Add(line);
            Image image = line.GetComponent<Image>();
            image.color = new Color(0.78f, 0.62f, 0.26f, 0.55f);

            RectTransform rect = line.GetComponent<RectTransform>();
            Vector2 delta = end - start;
            rect.anchorMin = new Vector2(0.5f, 0.5f);
            rect.anchorMax = new Vector2(0.5f, 0.5f);
            rect.sizeDelta = new Vector2(delta.magnitude, 3f);
            rect.anchoredPosition = start + delta * 0.5f;
            rect.localRotation = Quaternion.Euler(0f, 0f, Mathf.Atan2(delta.y, delta.x) * Mathf.Rad2Deg);
        }

        private Text CreateText(Transform parent, string name, string value, int fontSize, TextAnchor anchor)
        {
            GameObject textObject = new GameObject(name, typeof(RectTransform), typeof(Text));
            textObject.transform.SetParent(parent, false);
            Text text = textObject.GetComponent<Text>();
            text.font = uiFont != null ? uiFont : Resources.GetBuiltinResource<Font>("Arial.ttf");
            text.fontSize = fontSize;
            text.alignment = anchor;
            text.color = new Color(0.95f, 0.94f, 0.9f, 1f);
            text.text = value;
            text.resizeTextForBestFit = true;
            text.resizeTextMinSize = 10;
            text.resizeTextMaxSize = fontSize;
            return text;
        }

        private void ClearTree()
        {
            for (int i = nodesRoot != null ? nodesRoot.childCount - 1 : -1; i >= 0; i--)
            {
                Destroy(nodesRoot.GetChild(i).gameObject);
            }

            for (int i = 0; i < spawnedLines.Count; i++)
            {
                if (spawnedLines[i] != null)
                {
                    Destroy(spawnedLines[i]);
                }
            }

            nodes.Clear();
            spawnedLines.Clear();
        }
    }
}