using UnityEngine;
using UnityEngine.UI;
using UnityEngine.Video;
using TMPro;
using System.IO;
using System.Collections.Generic;

public class ContentViewer : MonoBehaviour
{
    [Header("父物体")]
    public GameObject textRoot;
    public GameObject imageRoot;
    public GameObject videoRoot;

    [Header("展示组件")]
    public TMP_Text textDisplay;
    public Image imageDisplay;
    public VideoPlayer videoPlayer;
    public RawImage videoRawImage;

    [Header("切换按钮")]
    public Button prevButton;
    public Button nextButton;

    public Button close;

    private List<string> files = new List<string>();
    private int index = 0;

    void Awake()
    {
        HideAll();

        prevButton.onClick.AddListener(Prev);
        nextButton.onClick.AddListener(Next);
        close.onClick.AddListener(OnClose);
    }


    void OnClose()
    {
        Destroy(transform.parent.gameObject);
    }

    void HideAll()
    {
        textRoot.SetActive(false);
        imageRoot.SetActive(false);
        videoRoot.SetActive(false);
    }

    // ----- 加载文件夹，并按文本→图片→视频排序 -----
    public void LoadFolder(string folderPath)
    {
        if (!Directory.Exists(folderPath))
        {
            Debug.LogError("路径不存在: " + folderPath);
            return;
        }

        files.Clear();

        files.AddRange(Directory.GetFiles(folderPath, "*.txt"));
        files.AddRange(Directory.GetFiles(folderPath, "*.png"));
        files.AddRange(Directory.GetFiles(folderPath, "*.jpg"));
        files.AddRange(Directory.GetFiles(folderPath, "*.jpeg"));
        files.AddRange(Directory.GetFiles(folderPath, "*.mp4"));
        files.AddRange(Directory.GetFiles(folderPath, "*.mov"));

        if (files.Count == 0)
        {
            Debug.LogWarning("文件夹无可用文件: " + folderPath);
            return;
        }

        // 排序规则
        files.Sort((a, b) =>
        {
            int typeA = GetTypeOrder(a);
            int typeB = GetTypeOrder(b);

            if (typeA != typeB)
                return typeA.CompareTo(typeB);

            return Path.GetFileName(a).CompareTo(Path.GetFileName(b));
        });

        index = 0;
        ShowCurrent();
        UpdateButtonState();
    }

    private int GetTypeOrder(string path)
    {
        string ext = Path.GetExtension(path).ToLower();
        if (ext == ".txt") return 0;
        if (ext == ".png" || ext == ".jpg" || ext == ".jpeg") return 1;
        if (ext == ".mp4" || ext == ".mov") return 2;
        return 99;
    }

    void ShowCurrent()
    {
        HideAll();

        string path = files[index];
        string ext = Path.GetExtension(path).ToLower();

        if (ext == ".txt")
        {
            textDisplay.text = File.ReadAllText(path);
            textRoot.SetActive(true);
        }
        else if (ext == ".png" || ext == ".jpg" || ext == ".jpeg")
        {
            byte[] data = File.ReadAllBytes(path);
            Texture2D tex = new Texture2D(2, 2);
            tex.LoadImage(data);
            Sprite sprite = Sprite.Create(tex, new Rect(0, 0, tex.width, tex.height), new Vector2(.5f, .5f));

            imageDisplay.sprite = sprite;
            imageRoot.SetActive(true);
        }
        else if (ext == ".mp4" || ext == ".mov")
        {
            videoPlayer.Stop();
            videoPlayer.url = path;

            RenderTexture rt = new RenderTexture(1920, 1080, 16);
            videoPlayer.targetTexture = rt;
            videoRawImage.texture = rt;

            videoRoot.SetActive(true);
            videoPlayer.Play();
        }

        UpdateButtonState();
    }

    // ----- 更新按钮状态 -----
    void UpdateButtonState()
    {
        prevButton.interactable = index > 0;
        nextButton.interactable = index < files.Count - 1;
    }

    public void Next()
    {
        if (index < files.Count - 1)
        {
            index++;
            ShowCurrent();
        }
    }

    public void Prev()
    {
        if (index > 0)
        {
            index--;
            ShowCurrent();
        }
    }
}