using System;
using System.Collections;
using System.Collections.Generic;
using TMPro;
using UnityEngine;
using UnityEngine.UI;
using XWorld.Framework.Protocol;
using UObject = UnityEngine.Object;

namespace XGame
{
    public sealed class WorldChatModule : MonoBehaviour
    {
        private const string ChatPrefabPath = "Assets/Game/Art/UI/Prefab/UI_CommonChat.prefab";
        private const int MaxMessages = 80;
        private const int MaxInputLength = 200;

        private GameObject view;
        private GameObject panelCollapsed;
        private GameObject panelChat;
        private Transform contentMessages;
        private GameObject otherTemplate;
        private GameObject selfTemplate;
        private TMP_InputField inputField;
        private TMP_Text inputPlaceholder;
        private TMP_Text inputValue;
        private ScrollRect scrollMessages;
        private bool opening;
        private int openVersion;
        private int localPlayerId;
        private readonly Queue<GameObject> messageRows = new Queue<GameObject>();

        public Action<string> OnSendWorldChat;

        public bool IsOpen => view != null;

        public void Initialize(int playerId, Action<string> sendWorldChat)
        {
            localPlayerId = playerId;
            OnSendWorldChat = sendWorldChat;
        }

        public IEnumerator OpenAsync()
        {
            if (view != null || opening)
            {
                yield break;
            }

            opening = true;
            int version = ++openVersion;
            UObject loaded = null;
            yield return XResLoader.coLoadRes(ChatPrefabPath, typeof(GameObject), obj => loaded = obj);
            opening = false;

            if (version != openVersion)
            {
                yield break;
            }

            GameObject prefab = loaded as GameObject;
            if (prefab == null)
            {
                Debug.LogError("[WorldChatModule] load chat prefab failed: " + ChatPrefabPath);
                yield break;
            }

            view = Instantiate(prefab);
            UIManager.AttachTo(UILayer.Normal, view);
            CacheControls();
            BindEvents();
            Collapse();
        }

        public void Close()
        {
            openVersion++;
            if (view != null)
            {
                Destroy(view);
                view = null;
            }
            messageRows.Clear();
            panelCollapsed = null;
            panelChat = null;
            contentMessages = null;
            otherTemplate = null;
            selfTemplate = null;
            inputField = null;
            inputPlaceholder = null;
            inputValue = null;
            scrollMessages = null;
            opening = false;
        }

        public void HandleWorldChatMessage(WorldChatMessageMsg message)
        {
            if (message == null)
            {
                return;
            }
            if (view == null)
            {
                XWCoroutine.StartCo(OpenThenAppend(message));
                return;
            }
            AppendMessage(message);
        }

        private IEnumerator OpenThenAppend(WorldChatMessageMsg message)
        {
            yield return OpenAsync();
            AppendMessage(message);
        }

        private void CacheControls()
        {
            if (view == null)
            {
                return;
            }

            panelCollapsed = FindGameObject("Panel_Collapsed");
            panelChat = FindGameObject("Panel_Chat");
            contentMessages = FindTransform("Content_Messages");
            otherTemplate = FindGameObject("Item_MessageOther_Template");
            selfTemplate = FindGameObject("Item_MessageSelf_Template");
            scrollMessages = FindComponent<ScrollRect>("Scroll_Messages");
            inputPlaceholder = FindComponent<TMP_Text>("Txt_InputPlaceholder");
            inputValue = FindComponent<TMP_Text>("Txt_InputValue");
            EnsureInputField();
        }

        private void BindEvents()
        {
            BindButton("Btn_CollapsedInput", Expand);
            BindButton("Btn_Close", Collapse);
            BindButton("Btn_Send", SendCurrentInput);
            BindButton("Btn_ClearInput", ClearInput);
            BindButton("InputHitArea", FocusInput);
            if (inputField != null)
            {
                inputField.onSubmit.RemoveListener(OnInputSubmitted);
                inputField.onSubmit.AddListener(OnInputSubmitted);
            }
        }

        private void EnsureInputField()
        {
            Transform hitArea = FindTransform("InputHitArea");
            if (hitArea == null)
            {
                return;
            }

            inputField = hitArea.GetComponent<TMP_InputField>();
            if (inputField == null)
            {
                inputField = hitArea.gameObject.AddComponent<TMP_InputField>();
            }

            Button button = hitArea.GetComponent<Button>();
            if (button != null)
            {
                button.onClick.RemoveAllListeners();
                button.onClick.AddListener(FocusInput);
            }

            TextMeshProUGUI textComponent = EnsureInputText(hitArea, "Txt_InputValue", ref inputValue, string.Empty, "#23384CFF");
            TextMeshProUGUI placeholderComponent = EnsureInputText(hitArea, "Txt_InputPlaceholder", ref inputPlaceholder, "输入聊天内容...", "#7A8DA1FF");
            if (textComponent == null)
            {
                Debug.LogError("[WorldChatModule] cannot create input text component.");
                inputField = null;
                return;
            }

            inputField.textComponent = textComponent;
            inputField.placeholder = placeholderComponent;
            inputField.targetGraphic = hitArea.GetComponent<Image>();
            inputField.characterLimit = MaxInputLength;
            inputField.lineType = TMP_InputField.LineType.SingleLine;
            inputField.contentType = TMP_InputField.ContentType.Standard;
            inputField.onValueChanged.RemoveListener(OnInputValueChanged);
            inputField.onValueChanged.AddListener(OnInputValueChanged);
            OnInputValueChanged(inputField.text);
        }

        private TextMeshProUGUI EnsureInputText(Transform parent, string nodeName, ref TMP_Text cached, string defaultText, string color)
        {
            bool created = false;
            TextMeshProUGUI text = cached as TextMeshProUGUI;
            if (text == null)
            {
                Transform existing = FindTransform(nodeName);
                text = existing == null ? null : existing.GetComponent<TextMeshProUGUI>();
            }
            if (text == null)
            {
                GameObject go = new GameObject(nodeName, typeof(RectTransform), typeof(TextMeshProUGUI));
                go.transform.SetParent(parent, false);
                RectTransform rt = go.GetComponent<RectTransform>();
                rt.anchorMin = Vector2.zero;
                rt.anchorMax = Vector2.one;
                rt.pivot = new Vector2(0.5f, 0.5f);
                rt.offsetMin = new Vector2(76f, 0f);
                rt.offsetMax = new Vector2(-72f, 0f);
                text = go.GetComponent<TextMeshProUGUI>();
                created = true;
                text.fontSize = 28f;
                text.alignment = TextAlignmentOptions.Left;
                text.raycastTarget = false;
                if (ColorUtility.TryParseHtmlString(color, out Color parsed))
                {
                    text.color = parsed;
                }
            }
            if (created)
            {
                text.text = defaultText ?? string.Empty;
            }
            cached = text;
            return text;
        }

        private void Expand()
        {
            if (panelCollapsed != null) panelCollapsed.SetActive(false);
            if (panelChat != null) panelChat.SetActive(true);
            FocusInput();
        }

        private void Collapse()
        {
            if (panelCollapsed != null) panelCollapsed.SetActive(true);
            if (panelChat != null) panelChat.SetActive(false);
        }

        private void FocusInput()
        {
            if (inputField == null)
            {
                return;
            }
            inputField.Select();
            inputField.ActivateInputField();
        }

        private void ClearInput()
        {
            if (inputField != null)
            {
                inputField.text = string.Empty;
            }
        }

        private void OnInputSubmitted(string text)
        {
            SendCurrentInput();
        }

        private void SendCurrentInput()
        {
            string text = inputField == null ? string.Empty : inputField.text;
            text = (text ?? string.Empty).Trim();
            if (text.Length == 0)
            {
                return;
            }
            if (text.Length > MaxInputLength)
            {
                text = text.Substring(0, MaxInputLength);
            }
            OnSendWorldChat?.Invoke(text);
            ClearInput();
            FocusInput();
        }

        private void OnInputValueChanged(string text)
        {
            if (inputPlaceholder != null)
            {
                inputPlaceholder.gameObject.SetActive(string.IsNullOrEmpty(text));
            }
        }

        private void AppendMessage(WorldChatMessageMsg message)
        {
            CacheControls();
            if (contentMessages == null)
            {
                return;
            }

            bool isSelf = message.PlayerId == localPlayerId;
            GameObject template = isSelf ? selfTemplate : otherTemplate;
            if (template == null)
            {
                return;
            }

            GameObject row = Instantiate(template, contentMessages);
            row.name = isSelf ? "Item_MessageSelf" : "Item_MessageOther";
            row.SetActive(true);
            if (isSelf)
            {
                SetChildText(row.transform, "Txt_SelfMessage", message.Text);
            }
            else
            {
                SetChildText(row.transform, "Txt_OtherName", string.IsNullOrEmpty(message.PlayerName) ? "玩家" : message.PlayerName);
                SetChildText(row.transform, "Txt_OtherMessage", message.Text);
            }

            messageRows.Enqueue(row);
            while (messageRows.Count > MaxMessages)
            {
                GameObject old = messageRows.Dequeue();
                if (old != null)
                {
                    Destroy(old);
                }
            }

            if (scrollMessages != null)
            {
                StartCoroutine(ScrollToBottomNextFrame());
            }
        }

        private IEnumerator ScrollToBottomNextFrame()
        {
            yield return null;
            Canvas.ForceUpdateCanvases();
            if (scrollMessages != null)
            {
                scrollMessages.verticalNormalizedPosition = 0f;
            }
        }

        private void BindButton(string nodeName, UnityEngine.Events.UnityAction action)
        {
            Button button = FindComponent<Button>(nodeName);
            if (button == null)
            {
                return;
            }
            button.onClick.RemoveAllListeners();
            button.onClick.AddListener(action);
        }

        private GameObject FindGameObject(string nodeName)
        {
            Transform t = FindTransform(nodeName);
            return t == null ? null : t.gameObject;
        }

        private Transform FindTransform(string nodeName)
        {
            return view == null ? null : view.transform.FindTransform(nodeName);
        }

        private T FindComponent<T>(string nodeName) where T : Component
        {
            Transform t = FindTransform(nodeName);
            return t == null ? null : t.GetComponent<T>();
        }

        private static void SetChildText(Transform root, string childName, string text)
        {
            Transform t = root.FindTransform(childName);
            if (t == null)
            {
                return;
            }
            TMP_Text label = t.GetComponent<TMP_Text>();
            if (label != null)
            {
                label.text = text ?? string.Empty;
            }
        }
    }
}