using System.Collections.Generic;
using Ichni.Story.Dialogue;
using TMPro;
using UnityEngine;

namespace Ichni.Story.UI
{
    /// <summary>
    /// 文本块视图。点击后（阶段 2）将通过 Yarn Spinner 进入对应节点的对话。
    /// </summary>
    public class TextBlockView : StoryBlockView
    {
        [Header("Text Block")] 
        public TMP_Text storyIdText;
        public TMP_Text titleText;

        [Tooltip("三种状态对应的背景预制体，生成 block 时按当前状态实例化为第一个子物体")]
        public Dictionary<StoryBlockState, GameObject> blockVisuals = new Dictionary<StoryBlockState, GameObject>();

        /// <summary>该文本块对应的 Yarn 节点名。</summary>
        public string YarnNodeName { get; private set; }

        // 当前已实例化的状态背景对象；状态切换时销毁并替换
        private GameObject _currentVisual;

        public override void Initialize(StoryBlockDefinition def, Vector2 position, StoryBlockState blockState)
        {
            // 注意：base.Initialize 末尾会调用 ApplyState(state)，届时已生成对应背景
            base.Initialize(def, position, blockState);

            YarnNodeName = def.yarnNodeName;

            if (storyIdText != null)
                storyIdText.text = def.blockId;

            // 阶段 5 将接入 Unity Localization；此处占位直接显示 titleKey
            if (titleText != null)
                titleText.text = def.titleKey;
        }

        /// <summary>
        /// 应用状态：在基类逻辑（按钮可交互性）之外，切换到对应状态的背景视觉。
        /// </summary>
        public override void ApplyState(StoryBlockState newState)
        {
            base.ApplyState(newState);
            UpdateVisual(newState);
        }

        /// <summary>
        /// 按当前状态实例化对应的背景预制体，作为第一个子物体（位于文本/端口/按钮之下），
        /// 并拉伸铺满整个 block。状态切换时先销毁旧背景。
        /// </summary>
        private void UpdateVisual(StoryBlockState newState)
        {
            if (_currentVisual != null)
            {
                Destroy(_currentVisual);
                _currentVisual = null;
            }

            if (blockVisuals == null ||
                !blockVisuals.TryGetValue(newState, out GameObject prefab) ||
                prefab == null)
            {
                Debug.LogWarning($"[TextBlockView] block '{blockId}' 缺少状态 {newState} 的背景预制体（blockVisuals 未配置）。");
                return;
            }

            _currentVisual = Instantiate(prefab, blockRect);
            _currentVisual.transform.SetAsFirstSibling();

            // 背景铺满整个 block
            if (_currentVisual.transform is RectTransform visualRect)
            {
                visualRect.anchorMin = Vector2.zero;
                visualRect.anchorMax = Vector2.one;
                visualRect.offsetMin = Vector2.zero;
                visualRect.offsetMax = Vector2.zero;
                visualRect.localScale = Vector3.one;
            }
        }

        protected override void OnClicked()
        {
            if (StoryDialogueController.instance == null)
            {
                Debug.LogWarning($"[TextBlockView] 场景中缺少 StoryDialogueController，无法播放 block '{blockId}' 的对话。");
                return;
            }

            StoryDialogueController.instance.PlayBlock(this);
        }
    }
}