using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using TMPro;
using BaseGames.Core.Events;

namespace BaseGames.UI.HUD
{
    public class HUDController : MonoBehaviour
    {
        [Header("HP")]
        [SerializeField] private Transform  _hpContainer;
        [SerializeField] private GameObject _hpCellPrefab;

        [Header("Gauges")]
        [SerializeField] private Image    _soulGaugeFill;
        [SerializeField] private Image    _spiritGaugeFill;
        [SerializeField] private TMP_Text _geoText;

        [Header("Spring Charges")]
        [SerializeField] private Transform  _springContainer;
        [SerializeField] private GameObject _springIconPrefab;

        [Header("Form")]
        [SerializeField] private Image[] _formIcons;

        [Header("Interact Prompt")]
        [SerializeField] private TMP_Text   _interactText;
        [SerializeField] private GameObject _interactPromptRoot;

        [Header("Event Channels - Subscribe")]
        [SerializeField] private IntEventChannelSO    _onHPChanged;
        [SerializeField] private IntEventChannelSO    _onMaxHPChanged;
        [SerializeField] private IntEventChannelSO    _onSoulPowerChanged;
        [SerializeField] private IntEventChannelSO    _onSpiritPowerChanged;
        [SerializeField] private IntEventChannelSO    _onGeoChanged;
        [SerializeField] private IntEventChannelSO    _onSpringChargesChanged;
        [SerializeField] private IntEventChannelSO    _onFormChanged;
        [SerializeField] private StringEventChannelSO _onShowInteractPrompt;
        [SerializeField] private VoidEventChannelSO   _onHideInteractPrompt;

        private readonly List<GameObject> _hpCells     = new();
        private readonly List<GameObject> _springIcons = new();

        private void OnEnable()
        {
            if (_onHPChanged            != null) _onHPChanged.OnEventRaised            += UpdateHP;
            if (_onMaxHPChanged         != null) _onMaxHPChanged.OnEventRaised         += RebuildHPCells;
            if (_onSoulPowerChanged     != null) _onSoulPowerChanged.OnEventRaised     += UpdateSoul;
            if (_onSpiritPowerChanged   != null) _onSpiritPowerChanged.OnEventRaised   += UpdateSpirit;
            if (_onGeoChanged           != null) _onGeoChanged.OnEventRaised           += UpdateGeo;
            if (_onSpringChargesChanged != null) _onSpringChargesChanged.OnEventRaised += RebuildSpringIcons;
            if (_onFormChanged          != null) _onFormChanged.OnEventRaised          += UpdateFormIcon;
            if (_onShowInteractPrompt   != null) _onShowInteractPrompt.OnEventRaised   += ShowInteractPrompt;
            if (_onHideInteractPrompt   != null) _onHideInteractPrompt.OnEventRaised   += HideInteractPrompt;
        }

        private void OnDisable()
        {
            if (_onHPChanged            != null) _onHPChanged.OnEventRaised            -= UpdateHP;
            if (_onMaxHPChanged         != null) _onMaxHPChanged.OnEventRaised         -= RebuildHPCells;
            if (_onSoulPowerChanged     != null) _onSoulPowerChanged.OnEventRaised     -= UpdateSoul;
            if (_onSpiritPowerChanged   != null) _onSpiritPowerChanged.OnEventRaised   -= UpdateSpirit;
            if (_onGeoChanged           != null) _onGeoChanged.OnEventRaised           -= UpdateGeo;
            if (_onSpringChargesChanged != null) _onSpringChargesChanged.OnEventRaised -= RebuildSpringIcons;
            if (_onFormChanged          != null) _onFormChanged.OnEventRaised          -= UpdateFormIcon;
            if (_onShowInteractPrompt   != null) _onShowInteractPrompt.OnEventRaised   -= ShowInteractPrompt;
            if (_onHideInteractPrompt   != null) _onHideInteractPrompt.OnEventRaised   -= HideInteractPrompt;
        }

        private void UpdateHP(int current)
        {
            for (int i = 0; i < _hpCells.Count; i++)
                if (_hpCells[i] != null) _hpCells[i].SetActive(i < current);
        }

        private void RebuildHPCells(int max)
        {
            foreach (var cell in _hpCells)
                if (cell != null) Destroy(cell);
            _hpCells.Clear();
            if (_hpContainer == null || _hpCellPrefab == null) return;
            for (int i = 0; i < max; i++)
                _hpCells.Add(Instantiate(_hpCellPrefab, _hpContainer));
        }

        private void UpdateSoul(int val)
        {
            if (_soulGaugeFill != null) _soulGaugeFill.fillAmount = val / 100f;
        }

        private void UpdateSpirit(int val)
        {
            if (_spiritGaugeFill != null) _spiritGaugeFill.fillAmount = val / 100f;
        }

        private void UpdateGeo(int val)
        {
            if (_geoText != null) _geoText.text = val.ToString();
        }

        private void RebuildSpringIcons(int charges)
        {
            foreach (var icon in _springIcons)
                if (icon != null) Destroy(icon);
            _springIcons.Clear();
            if (_springContainer == null || _springIconPrefab == null) return;
            for (int i = 0; i < charges; i++)
                _springIcons.Add(Instantiate(_springIconPrefab, _springContainer));
        }

        private void UpdateFormIcon(int formIndex)
        {
            if (_formIcons == null) return;
            for (int i = 0; i < _formIcons.Length; i++)
                if (_formIcons[i] != null) _formIcons[i].enabled = (i == formIndex);
        }

        private void ShowInteractPrompt(string text)
        {
            if (_interactText != null) _interactText.text = text;
            if (_interactPromptRoot != null) _interactPromptRoot.SetActive(true);
        }

        private void HideInteractPrompt()
        {
            if (_interactPromptRoot != null) _interactPromptRoot.SetActive(false);
        }
    }
}