using System;
using System.Collections.Generic;
using System.Reflection;
using TMPro;
using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.InputSystem;
using UnityEngine.UI;
using RR.Common.Managers;
using RR.Common.Prizes;
using RR.Common.Utility;

namespace RR.Common.UI
{
    /// <summary>
    /// Отдельная модалка глобальной настройки QR-кодов по градациям.
    /// Не привязана к уровням: уровень выбирает только qrTier в LevelPrizeSettingsModal.
    /// </summary>
    public class QRCodeSettingsModal : Modal
    {
        [Header("UI")]
        [SerializeField] private TMP_Text titleText;
        [SerializeField] private TMP_Text tierLabel;
        [SerializeField] private TMP_Text prizeTextLabel;
        [SerializeField] private Button editPrizeTextButton;
        [SerializeField] private TextInputModal textInputModal;

        [Header("Rows")]
        [SerializeField] private RectTransform tierRow;
        [SerializeField] private RectTransform prizeTextRow;

        [Header("Pointer")]
        [SerializeField] private UIRowPointer rowPointer;

        [Header("Close")]
        [SerializeField] private Button closeModalButton;

        [Header("Navigation")]
        [SerializeField] private InputActionReference navigateAction;
        [SerializeField] private InputActionReference submitAction;
        [SerializeField] private float deadZone = 0.5f;

        [Header("Behaviour")]
        [SerializeField] private bool createEntryIfMissing = true;
        [SerializeField] private string prizeTextModalTitle = "Введите текст приза QR";
        [SerializeField] private int prizeTextMaxLength = 12;

        private static readonly QRTier[] EditableTiers = { QRTier.Bronze, QRTier.Silver, QRTier.Gold };
        private const int MaxPrizeTextLength = 12;
        private const int RowTier = 0;
        private const int RowPrizeText = 1;
        private const int RowClose = 2;
        private const int RowCount = 3;

        private PrizeSystemManager _manager;
        private List<QRCodeInfo> _workingEntries;
        private int _currentTierIndex;
        private int _activeRow;
        private string _currentPrizeText = string.Empty;
        private bool _axisHeldX;
        private bool _axisHeldY;
        private bool _isPrizeTextInputOpen;
        private Selectable _pendingFocusTarget;
        private int _pendingFocusFrames;
        private Selectable _tierRowSelectable;
        private Selectable _prizeTextRowSelectable;
        private RectTransform _prizeTextPointerTarget;

        protected override void Awake()
        {
            base.Awake();

            if (editPrizeTextButton != null)
            {
                Graphic buttonGraphic = editPrizeTextButton.GetComponent<Graphic>();
                if (buttonGraphic != null)
                {
                    editPrizeTextButton.targetGraphic = buttonGraphic;
                }

                editPrizeTextButton.onClick.AddListener(OpenPrizeTextInput);
            }

            if (textInputModal == null)
            {
                textInputModal = FindFirstObjectByType<TextInputModal>(FindObjectsInactive.Include);
            }
        }

        protected override void OnEnable()
        {
            base.OnEnable();

            if (navigateAction != null && navigateAction.action != null)
            {
                navigateAction.action.Enable();
            }
        }

        protected override void OnDisable()
        {
            _isPrizeTextInputOpen = false;
            _pendingFocusTarget = null;
            _pendingFocusFrames = 0;
            _axisHeldX = false;
            _axisHeldY = false;
            base.OnDisable();
        }

        protected override void OnReturnedToTop()
        {
            _isPrizeTextInputOpen = false;
            _pendingFocusTarget = null;
            _pendingFocusFrames = 0;
            _axisHeldX = false;
            _axisHeldY = false;
            RefreshRowHighlights();
        }

        private void OnDestroy()
        {
            if (editPrizeTextButton != null)
            {
                editPrizeTextButton.onClick.RemoveListener(OpenPrizeTextInput);
            }

            if (textInputModal != null)
            {
                textInputModal.OnTextConfirmed -= OnPrizeTextConfirmed;
                textInputModal.OnTextCancelled -= OnPrizeTextCancelled;
            }
        }

        public override void Open()
        {
            PrepareForEditing();
            base.Open();
            RefreshRowHighlights();
        }

        public void OpenForEditing()
        {
            Open();
        }

        public override void Close()
        {
            Save();
            base.Close();
        }

        private void Save()
        {
            ApplyCurrentFieldValues();

            if (_manager == null)
            {
                Debug.LogWarning("[QRCodeSettingsModal] PrizeSystemManager не найден.");
                return;
            }

            _manager.SetQRCodeConfigs(_workingEntries);
        }

        private void PrepareForEditing()
        {
            _manager = PrizeSystemManager.Instance;
            _workingEntries = _manager != null ? _manager.GetQRCodeConfigs() : new List<QRCodeInfo>();

            _currentTierIndex = Mathf.Clamp(_currentTierIndex, 0, EditableTiers.Length - 1);
            _activeRow = RowTier;
            AutoResolveRows();
            EnsureRowSelectables();
            LoadCurrentTierIntoFields();
            RefreshRowHighlights();
        }

        private void ProcessNavigationInput()
        {
            if (navigateAction == null || navigateAction.action == null)
            {
                _axisHeldX = false;
                _axisHeldY = false;
                return;
            }

            Vector2 value = navigateAction.action.ReadValue<Vector2>();

            if (Mathf.Abs(value.y) >= deadZone)
            {
                if (!_axisHeldY)
                {
                    _axisHeldY = true;
                    MoveRow(value.y > 0f ? -1 : 1);
                }
            }
            else
            {
                _axisHeldY = false;
            }

            if (Mathf.Abs(value.x) >= deadZone)
            {
                if (!_axisHeldX)
                {
                    _axisHeldX = true;
                    HandleLeftRight(value.x > 0f ? 1 : -1);
                }
            }
            else
            {
                _axisHeldX = false;
            }
        }

        private void Update()
        {
            if (!_isOpen || _isPrizeTextInputOpen)
            {
                return;
            }

            ProcessNavigationInput();
            HandleSubmit();
        }

        private void LateUpdate()
        {
            if (!_isOpen || _isPrizeTextInputOpen)
            {
                return;
            }

            ApplyPendingFocus();
        }

        private void MoveRow(int delta)
        {
            _activeRow = (_activeRow + delta + RowCount) % RowCount;
            RefreshRowHighlights();
        }

        private void HandleLeftRight(int direction)
        {
            if (_activeRow != RowTier)
                return;

            ApplyCurrentFieldValues();
            _currentTierIndex = (_currentTierIndex + direction + EditableTiers.Length) % EditableTiers.Length;
            LoadCurrentTierIntoFields();
            RefreshRowHighlights();
        }

        private void LoadCurrentTierIntoFields()
        {
            if (titleText != null)
            {
                titleText.text = $"Настройки QR: {GetTierName(CurrentTier)}";
            }

            if (tierLabel != null)
            {
                tierLabel.text = GetTierName(CurrentTier);
            }

            List<QRCodeInfo> entries = GetEntriesForTier(CurrentTier, includeFallbackTemplates: false);
            _currentPrizeText = ResolveDisplayedPrizeText(entries);
            UpdatePrizeTextLabel(_currentPrizeText);
        }

        private void ApplyCurrentFieldValues()
        {
            if (_workingEntries == null)
            {
                return;
            }

            _currentPrizeText = NormalizePrizeText(_currentPrizeText);

            List<int> tierIndices = GetEntryIndicesForTier(CurrentTier);
            if (tierIndices.Count > 0)
            {
                for (int i = 0; i < tierIndices.Count; i++)
                {
                    int index = tierIndices[i];
                    QRCodeInfo info = _workingEntries[index];
                    info.tier = CurrentTier;
                    info.prizeText = _currentPrizeText;
                    _workingEntries[index] = info;
                }

                return;
            }

            if (!createEntryIfMissing)
            {
                return;
            }

            List<QRCodeInfo> templateEntries = GetEntriesForTier(QRTier.None, includeFallbackTemplates: false);
            if (templateEntries.Count == 0)
            {
                templateEntries.Add(CreateDefaultEntry(CurrentTier));
            }

            for (int i = 0; i < templateEntries.Count; i++)
            {
                QRCodeInfo clone = templateEntries[i];
                clone.tier = CurrentTier;
                clone.prizeText = _currentPrizeText;
                _workingEntries.Add(clone);
            }
        }

        private static QRCodeInfo CreateDefaultEntry(QRTier tier)
        {
            return new QRCodeInfo
            {
                tier = tier,
                generateQRCode = true,
                linkPrefix = string.Empty,
                messageFormat = "{0}",
                prizeText = string.Empty,
                darkColor = new Vector3(0f, 0f, 0f),
                lightColor = new Vector3(1f, 1f, 1f)
            };
        }

        private void OpenPrizeTextInput()
        {
            if (textInputModal == null)
            {
                Debug.LogWarning("[QRCodeSettingsModal] TextInputModal не назначен.");
                return;
            }

            _isPrizeTextInputOpen = true;
            FocusSelectable(_prizeTextRowSelectable != null ? _prizeTextRowSelectable : editPrizeTextButton);

            textInputModal.OnTextConfirmed -= OnPrizeTextConfirmed;
            textInputModal.OnTextCancelled -= OnPrizeTextCancelled;
            textInputModal.OnTextConfirmed += OnPrizeTextConfirmed;
            textInputModal.OnTextCancelled += OnPrizeTextCancelled;

            _currentPrizeText = NormalizePrizeText(_currentPrizeText);
            textInputModal.SetAlphabet(TextInputAlphabets.RussianPrizeText);
            textInputModal.SetCellCount(GetPrizeTextCellCount());
            textInputModal.OpenForInput(prizeTextModalTitle, _currentPrizeText);
        }

        public void OpenPrizeTextEditor()
        {
            OpenPrizeTextInput();
        }

        private void OnPrizeTextConfirmed(string text)
        {
            _isPrizeTextInputOpen = false;

            if (textInputModal != null)
            {
                textInputModal.OnTextConfirmed -= OnPrizeTextConfirmed;
                textInputModal.OnTextCancelled -= OnPrizeTextCancelled;
            }

            _currentPrizeText = NormalizePrizeText(text);
            UpdatePrizeTextLabel(_currentPrizeText);
            FocusSelectable(_prizeTextRowSelectable != null ? _prizeTextRowSelectable : editPrizeTextButton);
        }

        private void OnPrizeTextCancelled()
        {
            _isPrizeTextInputOpen = false;

            if (textInputModal != null)
            {
                textInputModal.OnTextConfirmed -= OnPrizeTextConfirmed;
                textInputModal.OnTextCancelled -= OnPrizeTextCancelled;
            }

            FocusSelectable(_prizeTextRowSelectable != null ? _prizeTextRowSelectable : editPrizeTextButton);
        }

        private void UpdatePrizeTextLabel(string text)
        {
            if (prizeTextLabel != null)
            {
                string normalized = NormalizePrizeText(text);
                prizeTextLabel.text = string.IsNullOrWhiteSpace(normalized) ? "<пусто>" : normalized;
            }
        }

        private void RefreshRowHighlights()
        {
            RectTransform target = GetActiveRowTransform();
            Selectable selectableToFocus = null;

            switch (_activeRow)
            {
                case RowTier:
                    selectableToFocus = _tierRowSelectable;
                    break;
                case RowPrizeText:
                    selectableToFocus = _prizeTextRowSelectable;
                    break;
                case RowClose:
                    selectableToFocus = closeModalButton;
                    break;
            }

            if (_activeRow == RowClose)
            {
                if (rowPointer != null)
                {
                    rowPointer.Hide();
                }
            }
            else if (rowPointer != null && target != null)
            {
                rowPointer.SetTarget(target);
            }

            FocusSelectable(selectableToFocus);
        }

        private void AutoResolveRows()
        {
            if (tierRow == null && tierLabel != null)
            {
                tierRow = tierLabel.transform.parent as RectTransform;
            }

            if (prizeTextRow == null)
            {
                if (prizeTextLabel != null)
                    prizeTextRow = prizeTextLabel.transform.parent as RectTransform;
                else if (editPrizeTextButton != null)
                    prizeTextRow = editPrizeTextButton.transform.parent as RectTransform;
            }

            _prizeTextPointerTarget = ResolvePrizeTextPointerTarget();
        }

        private QRTier CurrentTier => EditableTiers[Mathf.Clamp(_currentTierIndex, 0, EditableTiers.Length - 1)];

        private static string GetTierName(QRTier tier)
        {
            return tier switch
            {
                QRTier.Bronze => "Бронзовый",
                QRTier.Silver => "Серебряный",
                QRTier.Gold => "Золотой",
                _ => "Не задан"
            };
        }

        private List<QRCodeInfo> GetEntriesForTier(QRTier tier, bool includeFallbackTemplates)
        {
            List<QRCodeInfo> result = new();
            if (_workingEntries == null)
                return result;

            for (int i = 0; i < _workingEntries.Count; i++)
            {
                if (_workingEntries[i].tier == tier)
                    result.Add(_workingEntries[i]);
            }

            if (result.Count == 0 && includeFallbackTemplates && tier != QRTier.None)
            {
                for (int i = 0; i < _workingEntries.Count; i++)
                {
                    if (_workingEntries[i].tier == QRTier.None)
                        result.Add(_workingEntries[i]);
                }
            }

            return result;
        }

        private List<int> GetEntryIndicesForTier(QRTier tier)
        {
            List<int> result = new();
            if (_workingEntries == null)
                return result;

            for (int i = 0; i < _workingEntries.Count; i++)
            {
                if (_workingEntries[i].tier == tier)
                    result.Add(i);
            }

            return result;
        }

        private string ResolveDisplayedPrizeText(List<QRCodeInfo> tierEntries)
        {
            if (tierEntries == null || tierEntries.Count == 0)
                return string.Empty;

            for (int i = 0; i < tierEntries.Count; i++)
            {
                string candidate = NormalizePrizeText(tierEntries[i].prizeText);
                if (!string.IsNullOrWhiteSpace(candidate))
                    return candidate;
            }

            return string.Empty;
        }

        private int GetPrizeTextCellCount()
        {
            return Mathf.Clamp(prizeTextMaxLength, 1, MaxPrizeTextLength);
        }

        private RectTransform GetActiveRowTransform()
        {
            return _activeRow switch
            {
                RowTier => tierRow,
                RowPrizeText => _prizeTextPointerTarget,
                _ => null
            };
        }

        private void EnsureRowSelectables()
        {
            _tierRowSelectable = EnsureRowSelectable(tierRow);
            _prizeTextRowSelectable = editPrizeTextButton != null
                ? editPrizeTextButton
                : EnsureRowSelectable(_prizeTextPointerTarget);
        }

        private RectTransform ResolvePrizeTextPointerTarget()
        {
            if (editPrizeTextButton != null)
            {
                RectTransform buttonRect = editPrizeTextButton.transform as RectTransform;
                if (buttonRect != null)
                {
                    return buttonRect;
                }
            }

            if (prizeTextRow != null)
            {
                return prizeTextRow;
            }

            return prizeTextLabel != null ? prizeTextLabel.transform.parent as RectTransform : null;
        }

        private Selectable EnsureRowSelectable(RectTransform row)
        {
            if (row == null)
            {
                return null;
            }

            Selectable selectable = row.GetComponent<Selectable>();
            if (selectable == null)
            {
                selectable = row.gameObject.AddComponent<Selectable>();
                selectable.transition = Selectable.Transition.None;
                selectable.navigation = new Navigation { mode = Navigation.Mode.None };
            }

            selectable.interactable = true;
            return selectable;
        }

        private void FocusSelectable(Selectable selectable)
        {
            if (selectable == null || !selectable.gameObject.activeInHierarchy)
            {
                return;
            }

            SetFirstSelected(selectable);
            _pendingFocusTarget = selectable;
            _pendingFocusFrames = 2;
            ApplyPendingFocus();
        }

        private void ApplyPendingFocus()
        {
            if (_pendingFocusTarget == null || _pendingFocusFrames <= 0)
            {
                return;
            }

            if (EventSystem.current == null || !_pendingFocusTarget.gameObject.activeInHierarchy)
            {
                _pendingFocusTarget = null;
                _pendingFocusFrames = 0;
                return;
            }

            if (EventSystem.current.currentSelectedGameObject != _pendingFocusTarget.gameObject)
            {
                EventSystem.current.SetSelectedGameObject(null);
                EventSystem.current.SetSelectedGameObject(_pendingFocusTarget.gameObject);
                _pendingFocusTarget.Select();
            }

            _pendingFocusFrames--;
            if (_pendingFocusFrames <= 0)
            {
                _pendingFocusTarget = null;
            }
        }

        private void HandleSubmit()
        {
            InputAction currentSubmitAction = GetSubmitAction();
            if (currentSubmitAction == null || !currentSubmitAction.WasPerformedThisFrame())
            {
                return;
            }

            GameObject selectedObject = EventSystem.current != null ? EventSystem.current.currentSelectedGameObject : null;

            switch (_activeRow)
            {
                case RowPrizeText:
                    if (selectedObject == editPrizeTextButton?.gameObject)
                    {
                        return;
                    }

                    OpenPrizeTextInput();
                    break;
                case RowClose:
                    if (selectedObject == closeModalButton?.gameObject)
                    {
                        return;
                    }

                    Close();
                    break;
            }
        }

        private InputAction GetSubmitAction()
        {
            if (submitAction != null && submitAction.action != null)
            {
                return submitAction.action;
            }

            if (EventSystem.current?.currentInputModule == null)
            {
                return null;
            }

            object inputModule = EventSystem.current.currentInputModule;
            PropertyInfo submitProperty = inputModule.GetType().GetProperty("submit", BindingFlags.Instance | BindingFlags.Public);
            object submitObject = submitProperty != null ? submitProperty.GetValue(inputModule) : null;
            InputActionReference submitReference = submitObject as InputActionReference;
            return submitReference != null ? submitReference.action : null;
        }

        private string NormalizePrizeText(string text)
        {
            if (string.IsNullOrWhiteSpace(text))
            {
                return string.Empty;
            }

            string normalized = text.Trim();
            int maxLength = GetPrizeTextCellCount();
            if (normalized.Length > maxLength)
            {
                normalized = normalized.Substring(0, maxLength);
            }

            return normalized;
        }

    }
}