using UnityEngine;
using UnityEngine.UI;

public class QuestLogUI : MonoBehaviour
{
    public static QuestLogUI Instance { get; private set; }

    public GameObject root;
    public RectTransform content;
    public Font uiFont;
    public Color titleColor = new Color(1f, 0.74f, 0.25f);
    public Color textColor = new Color(0.92f, 0.9f, 0.82f);
    public Color mutedColor = new Color(0.7f, 0.7f, 0.7f);
    public KeyCode toggleKey = KeyCode.J;

    public bool IsOpen => root != null && root.activeSelf;

    private void Awake()
    {
        if (Instance != null && Instance != this)
        {
            Destroy(this);
            return;
        }

        Instance = this;
    }

    private void Start()
    {
        if (root != null)
        {
            root.SetActive(false);
        }

        Subscribe();
        Refresh();
    }

    private void OnEnable()
    {
        Subscribe();
    }

    private void OnDisable()
    {
        if (QuestManager.Instance != null)
        {
            QuestManager.Instance.OnQuestsChanged -= Refresh;
        }
    }

    private void Subscribe()
    {
        if (QuestManager.Instance != null)
        {
            QuestManager.Instance.OnQuestsChanged -= Refresh;
            QuestManager.Instance.OnQuestsChanged += Refresh;
        }
    }

    private void Update()
    {
        if (Input.GetKeyDown(toggleKey))
        {
            Toggle();
        }
    }

    public void Toggle()
    {
        if (root == null)
        {
            return;
        }

        bool next = !root.activeSelf;
        root.SetActive(next);
        Cursor.lockState = next ? CursorLockMode.None : CursorLockMode.Locked;
        Cursor.visible = next;
        Refresh();
    }

    public void Refresh()
    {
        if (content == null)
        {
            return;
        }

        ClearContent();

        if (QuestManager.Instance == null)
        {
            CreateText("QuestManager не найден", mutedColor, 16, FontStyle.Normal);
            return;
        }

        CreateText("Активные", titleColor, 22, FontStyle.Bold);
        if (QuestManager.Instance.ActiveQuests.Count == 0)
        {
            CreateText("Нет активных квестов", mutedColor, 16, FontStyle.Normal);
        }
        else
        {
            foreach (QuestState state in QuestManager.Instance.ActiveQuests)
            {
                CreateQuestBlock(state);
            }
        }

        CreateText("Завершённые", titleColor, 22, FontStyle.Bold);
        if (QuestManager.Instance.CompletedQuests.Count == 0)
        {
            CreateText("Пока пусто", mutedColor, 16, FontStyle.Normal);
        }
        else
        {
            foreach (QuestState state in QuestManager.Instance.CompletedQuests)
            {
                CreateQuestBlock(state);
            }
        }

        if (QuestManager.Instance.FailedQuests.Count > 0)
        {
            CreateText("Проваленные", titleColor, 22, FontStyle.Bold);
            foreach (QuestState state in QuestManager.Instance.FailedQuests)
            {
                CreateQuestBlock(state);
            }
        }
    }

    private void CreateQuestBlock(QuestState state)
    {
        if (state == null || state.questData == null)
        {
            return;
        }

        QuestData quest = state.questData;
        CreateText(quest.questName, titleColor, 18, FontStyle.Bold);
        CreateText(quest.description, textColor, 15, FontStyle.Normal);
        CreateText($"Статус: {state.status}", mutedColor, 14, FontStyle.Normal);

        for (int i = 0; i < quest.goals.Count; i++)
        {
            QuestGoal goal = quest.goals[i];
            CreateText($"{goal.GetDisplayName()} {state.GetProgress(i)}/{goal.requiredAmount}", textColor, 15, FontStyle.Normal);
        }

        float percent = QuestManager.Instance.GetQuestCompletionPercent(state);
        CreateText($"{BuildProgressBar(percent)} {Mathf.RoundToInt(percent * 100f)}%", titleColor, 15, FontStyle.Normal);
        CreateSpacer(8f);
    }

    private string BuildProgressBar(float percent)
    {
        const int length = 10;
        int filled = Mathf.RoundToInt(Mathf.Clamp01(percent) * length);
        return new string('█', filled) + new string('░', length - filled);
    }

    private void ClearContent()
    {
        for (int i = content.childCount - 1; i >= 0; i--)
        {
            Destroy(content.GetChild(i).gameObject);
        }
    }

    private void CreateSpacer(float height)
    {
        GameObject spacer = new GameObject("Quest Log Spacer", typeof(RectTransform));
        spacer.transform.SetParent(content, false);
        spacer.GetComponent<RectTransform>().sizeDelta = new Vector2(0f, height);
    }

    private void CreateText(string value, Color color, int size, FontStyle style)
    {
        GameObject line = new GameObject("Quest Log Text", typeof(RectTransform), typeof(Text));
        line.transform.SetParent(content, false);

        Text text = line.GetComponent<Text>();
        text.font = uiFont != null ? uiFont : Resources.GetBuiltinResource<Font>("Arial.ttf");
        text.fontSize = size;
        text.fontStyle = style;
        text.color = color;
        text.text = value;
        text.horizontalOverflow = HorizontalWrapMode.Wrap;
        text.verticalOverflow = VerticalWrapMode.Overflow;

        RectTransform rect = line.GetComponent<RectTransform>();
        rect.sizeDelta = new Vector2(0f, Mathf.Max(size + 10f, EstimateHeight(value, size)));
    }

    private float EstimateHeight(string value, int size)
    {
        if (string.IsNullOrEmpty(value))
        {
            return size + 8f;
        }

        int lineCount = Mathf.Max(1, Mathf.CeilToInt(value.Length / 42f));
        return lineCount * (size + 8f);
    }
}