using Cysharp.Threading.Tasks;
using DG.Tweening;
using System;
using System.Threading;
using TMPro;
using UnityEngine;
using UnityEngine.Serialization;

namespace CharacterSystem
{
    public class MessageBox : MonoBehaviour
    {
        [SerializeField] private Transform _frame;
        [SerializeField] private Vector2 _localPos;
        [SerializeField] private Vector3 _visibleScale = Vector3.one;
        [SerializeField, FormerlySerializedAs("nameLabel")] private TextMeshProUGUI _nameLabel;
        [SerializeField, FormerlySerializedAs("textField")] private TextMeshProUGUI _textField;
        [SerializeField] private AudioSource _audioSource;
        [SerializeField, FormerlySerializedAs("typeClip")] private AudioClip _typeClip;
        [SerializeField, Min(0.01f)] private float _minimumFontSize = 0.1f;
        [SerializeField, Min(0.01f)] private float _maximumFontSize = 0.24f;
        [SerializeField, Range(1, 16)] private int _fontSizeSearchIterations = 10;

        private CancellationTokenSource _cancellationTokenSource;
        private bool _isProcessing;
        private float _lastTypeSoundTime;
        private float _typeClipLength;

        private void OnDestroy()
            => Stop();

        public void Initialize(string characterName)
        {
            _nameLabel.text = characterName;
            _nameLabel.gameObject.SetActive(false);
            _frame.localPosition = _localPos;
            _frame.localScale = Vector3.zero;
            _lastTypeSoundTime = 0f;
            _typeClipLength = _typeClip != null ? _typeClip.length : 0f;
        }

        public void PlayReplica(Replica replica, bool force = false, bool showName = false)
        {
            if (_isProcessing && force == false)
                return;

            if (force)
                CancelCurrent();

            SetOptimalFontSize(replica.text ?? string.Empty);
            ProcessReplicaAsync(replica, showName).Forget();
        }

        public void Stop()
        {
            CancelCurrent();
            _cancellationTokenSource = null;
            _isProcessing = false;
            _audioSource.Stop();
            _frame.DOKill();
            _frame.localScale = Vector3.zero;
            _nameLabel.gameObject.SetActive(false);
            _textField.text = string.Empty;
        }

        private async UniTask ProcessReplicaAsync(Replica replica, bool showName)
        {
            var currentTokenSource = new CancellationTokenSource();
            _cancellationTokenSource = currentTokenSource;
            _isProcessing = true;

            try
            {
                await PlayReplicaAsync(replica, showName, currentTokenSource.Token);
            }
            catch (OperationCanceledException)
            {
            }
            finally
            {
                if (_cancellationTokenSource == currentTokenSource)
                {
                    _cancellationTokenSource = null;
                    _isProcessing = false;
                }

                currentTokenSource.Dispose();
            }
        }

        private async UniTask PlayReplicaAsync(Replica replica, bool showName, CancellationToken cancellationToken)
        {
            _nameLabel.gameObject.SetActive(showName);
            await GetShowSequence().WithCancellation(cancellationToken);
            await TypeAsync(replica, cancellationToken);
            await UniTask.Delay(1000, cancellationToken: cancellationToken);
            await GetHideSequence().WithCancellation(cancellationToken);

            _audioSource.Stop();
            _nameLabel.gameObject.SetActive(false);
            _textField.text = string.Empty;
        }

        private async UniTask TypeAsync(Replica replica, CancellationToken cancellationToken)
        {
            string message = replica.text ?? string.Empty;

            if (replica.clip != null)
            {
                _audioSource.clip = replica.clip;
                _audioSource.Play();

                if (SoundManager.instance != null)
                {
                    SoundManager.instance.MusicFade(
                        fadeDuration: 0.2f,
                        holdDuration: Mathf.Max(replica.clip.length - 0.2f, 0f),
                        targetVolumePercent: 0.5f);
                }
            }

            float duration = replica.Duration;
            float elapsedTime = 0f;
            _textField.text = string.Empty;

            while (elapsedTime < duration && cancellationToken.IsCancellationRequested == false)
            {
                float progress = Mathf.Clamp01(elapsedTime / duration);
                int symbolsToShow = Mathf.FloorToInt(message.Length * progress);
                _textField.text = message.Substring(0, symbolsToShow);

                bool shouldPlayTypeClip = _typeClipLength > 0f && Time.time - _lastTypeSoundTime > _typeClipLength;
                if (shouldPlayTypeClip)
                {
                    _audioSource.PlayOneShot(_typeClip);
                    _lastTypeSoundTime = Time.time;
                }

                await UniTask.Yield(cancellationToken);
                elapsedTime += Time.deltaTime;
            }

            if (cancellationToken.IsCancellationRequested == false)
                _textField.text = message;
        }

        private void CancelCurrent()
        {
            if (_cancellationTokenSource != null && _cancellationTokenSource.IsCancellationRequested == false)
                _cancellationTokenSource.Cancel();
        }

        private void SetOptimalFontSize(string message)
        {
            _textField.enableAutoSizing = false;

            float minimumFontSize = Mathf.Min(_minimumFontSize, _maximumFontSize);
            float maximumFontSize = Mathf.Max(_minimumFontSize, _maximumFontSize);

            if (string.IsNullOrEmpty(message))
            {
                _textField.fontSize = maximumFontSize;
                return;
            }

            Rect fieldRect = _textField.rectTransform.rect;
            Vector4 margin = _textField.margin;
            float availableWidth = Mathf.Max(fieldRect.width - margin.x - margin.z, 0.01f);
            float availableHeight = Mathf.Max(fieldRect.height - margin.y - margin.w, 0.01f);

            for (int i = 0; i < _fontSizeSearchIterations; i++)
            {
                float candidateFontSize = (minimumFontSize + maximumFontSize) * 0.5f;
                _textField.fontSize = candidateFontSize;
                Vector2 preferredSize = _textField.GetPreferredValues(message, availableWidth, 0f);

                if (preferredSize.x <= availableWidth && preferredSize.y <= availableHeight)
                    minimumFontSize = candidateFontSize;
                else
                    maximumFontSize = candidateFontSize;
            }

            _textField.fontSize = minimumFontSize;
        }

        private Sequence GetShowSequence()
        {
            Sequence sequence = DOTween.Sequence();
            sequence.Append(_frame.DOScale(_visibleScale, 0.2f).SetEase(Ease.OutBack));
            sequence.PlayForward();
            return sequence;
        }

        private Sequence GetHideSequence()
        {
            Sequence sequence = DOTween.Sequence();
            sequence.Append(_frame.DOScale(Vector3.zero, 0.2f).SetEase(Ease.InBack));
            sequence.PlayForward();
            return sequence;
        }
    }
}