using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Serialization;

public class RulesController : MonoBehaviour, IControlable
{
    [FormerlySerializedAs("pages")]
    [SerializeField] private List<GameObject> _pages;
    [SerializeField] private RectTransform _creditsContent;
    [SerializeField] private RectTransform _creditsViewport;
    [SerializeField] private TMPro.TMP_Text _sectionLabel;
    [SerializeField] private float _timeout = 60f;
    [SerializeField] private float _autoScrollSpeed = 35f;
    [SerializeField] private float _manualScrollSpeed = 300f;
    [SerializeField] private float _autoResumeDelay = 1f;

    private Menu _menu;
    private int _currentIndex;
    private float _lastActivityAt;
    private float _lastInputAt;
    private float _scrollOffset;

    public bool IsOpen { get; private set; }
    public bool ControlsEnabled { get; set; }

    private void Update()
    {
        if (!IsOpen)
            return;

        if (In.AnyButton())
            _lastActivityAt = Time.unscaledTime;

        if (Time.unscaledTime - _lastActivityAt >= _timeout)
            Close();
    }

    private void OnDisable()
    {
        if (IsOpen)
            Close();
    }

    public void Open()
    {
        if (IsOpen || _pages == null || _pages.Count == 0)
            return;

        _menu = FindFirstObjectByType<Menu>(FindObjectsInactive.Include);
        if (_menu == null || !_menu.ControlsEnabled)
            return;

        _menu.ControlsEnabled = false;
        _lastActivityAt = Time.unscaledTime;
        _lastInputAt = _lastActivityAt;
        _currentIndex = 0;
        IsOpen = true;
        ControlsEnabled = true;
        gameObject.SetActive(true);
        transform.SetAsLastSibling();
        OpenPage(_currentIndex);
        ControlsPerformer.Instance.SetControlable(this);
    }

    public void Close()
    {
        if (!IsOpen)
            return;

        IsOpen = false;
        ControlsEnabled = false;
        CloseAllPages();
        gameObject.SetActive(false);
        if (_menu != null)
        {
            _menu.ControlsEnabled = true;
            if (ControlsPerformer.Instance != null)
                ControlsPerformer.Instance.SetControlable(_menu);
        }
    }

    public void UpdateControls()
    {
        if (In.GetAction(JoystickSide.Both, InteractMode.Discrete))
        {
            Close();
            return;
        }

        SwitchPage(In.GetHorizontalAxis(JoystickSide.Both, InteractMode.Discrete));
        if (_currentIndex != _pages.Count - 1 || _creditsContent == null)
            return;

        int direction = In.GetVerticalAxis(JoystickSide.Both, InteractMode.Continious);
        if (In.AnyButton())
            _lastInputAt = Time.unscaledTime;

        float speed = direction != 0 ? -direction * _manualScrollSpeed
            : Time.unscaledTime - _lastInputAt >= _autoResumeDelay ? _autoScrollSpeed : 0f;
        float limit = Mathf.Max(0f, _creditsContent.rect.height - _creditsViewport.rect.height);
        if (direction == 0 && speed > 0f && _scrollOffset >= limit)
            _scrollOffset = 0f;
        _scrollOffset = Mathf.Clamp(_scrollOffset + speed * Time.unscaledDeltaTime, 0f, limit);
        _creditsContent.anchoredPosition = Vector2.up * _scrollOffset;
    }

    public void SwitchPage(int direction)
    {
        if (!IsOpen || direction == 0)
            return;

        _lastActivityAt = Time.unscaledTime;
        _currentIndex = (_currentIndex + (direction > 0 ? 1 : -1) + _pages.Count) % _pages.Count;
        OpenPage(_currentIndex);
    }

    private void OpenPage(int index)
    {
        CloseAllPages();
        _pages[index].SetActive(true);
        if (_sectionLabel != null)
            _sectionLabel.text = index == _pages.Count - 1 ? "КОНЕЦ ИГРЫ" : "ПРАВИЛА";
        _scrollOffset = 0f;
        _lastInputAt = Time.unscaledTime;
        if (_creditsContent != null)
            _creditsContent.anchoredPosition = Vector2.zero;
        if (index == _pages.Count - 1)
            RefreshCreditsLayout();
    }

    private void RefreshCreditsLayout()
    {
        if (_creditsContent == null || _creditsViewport == null)
            return;

        Canvas.ForceUpdateCanvases();
        float bottom = 0f;
        Vector3[] corners = new Vector3[4];
        foreach (TMPro.TMP_Text text in _creditsContent.GetComponentsInChildren<TMPro.TMP_Text>())
        {
            RectTransform rect = text.rectTransform;
            float height = text.GetPreferredValues(text.text, rect.rect.width, Mathf.Infinity).y;
            rect.SetSizeWithCurrentAnchors(RectTransform.Axis.Vertical, height);
            text.ForceMeshUpdate();
            rect.GetWorldCorners(corners);
            for (int i = 0; i < corners.Length; i++)
                bottom = Mathf.Max(bottom, _creditsContent.rect.yMax
                    - _creditsContent.InverseTransformPoint(corners[i]).y);
        }

        // Нижний отступ даёт последним строкам пройти через всю видимую область до повтора.
        _creditsContent.SetSizeWithCurrentAnchors(
            RectTransform.Axis.Vertical, bottom + _creditsViewport.rect.height);
    }

    private void CloseAllPages()
    {
        foreach (GameObject page in _pages)
            page.SetActive(false);
    }
}