using System.Diagnostics;
using System.IO;
using UnityEngine;
using System;
using System.Collections;

using Debug = UnityEngine.Debug;

public class WebViewLauncher : MonoBehaviour
{
    public static WebViewLauncher Instance { get; private set; }

    [Header("Web Settings")]
    public string startUrl = "https://www.baidu.com";
    public Vector2 windowSize = new Vector2(960, 600);
    public Vector2 windowPosition = new Vector2(100, 100);

    [Header("Editor Only Path")]
    public string editorExeRoot = @"E:\Unity\ban_total\fdBrowser";

    [Header("H5 Folder Paths")]
    public string h5EditorPath = @"E:\Unity\ban_total\ban_test\Bansonic_Data\StreamingAssets\h5LG";
    public string officialDocsPath = "_officialDocs";
    public string officialGamesPath = "_officialGames";
    public string thirdPartyGamesPath = "_thirdPartyGames";

    private Process webProcess;

    // Event invoked when web process main window handle becomes available
    public event Action WebViewReady;

    void Awake()
    {
        if (Instance != null)
        {
            Destroy(gameObject);
            return;
        }
        Instance = this;
        DontDestroyOnLoad(gameObject);
    }

    void Start()
    {
        // 扫描 H5 文件夹
        string h5Folder = GetH5FolderPath();
        if (!Directory.Exists(h5Folder))
        {
            Directory.CreateDirectory(h5Folder);
            Debug.Log("Created H5 folder: " + h5Folder);
        }

        var h5SubFolders = ScanH5Folders(h5Folder);
        if (h5SubFolders.Count > 0)
        {
            Debug.Log("Found H5 folders: " + string.Join(", ", h5SubFolders));
            string selectedFolder = h5SubFolders[0]; // 选择第一个
            startUrl = "file://" + Path.Combine(h5Folder, selectedFolder, "index.html");
            Debug.Log("Selected H5 folder: " + selectedFolder + ", URL: " + startUrl);
        }
        else
        {
            Debug.LogWarning("No H5 subfolders with index.html found in: " + h5Folder);
        }

        LaunchWebView();
    }

    void OnDestroy()
    {
        KillWebView();
    }

    public void KillWebView()
    {
        if (webProcess != null && !webProcess.HasExited)
        {
            webProcess.Kill();
            webProcess = null;
        }
    }

    void LaunchWebView()
    {
        string exePath = GetExePath();

        Debug.Log("WebView exe path: " + exePath);

        if (!File.Exists(exePath))
        {
            Debug.LogError("fdBrowser.exe not found: " + exePath);
            return;
        }

        // 初始参数可以给 0，后续由 PanelFollower 接管
        string args = $"0 0 800 600 \"{startUrl}\"";

        Debug.Log($"Launching: {exePath} {args}");

        ProcessStartInfo psi = new ProcessStartInfo
        {
            FileName = exePath,
            Arguments = args,
            UseShellExecute = true,  // 改为 true 以确保 exe 能启动
            WorkingDirectory = Path.GetDirectoryName(exePath)
        };

        try
        {
            webProcess = Process.Start(psi);
            Debug.Log("WebView2Host started successfully. Process ID: " + webProcess.Id);

            // Start coroutine to wait until main window handle is ready
            StartCoroutine(WaitForMainWindowHandle());
        }
        catch (System.Exception e)
        {
            Debug.LogError("Failed to start WebView2Host: " + e.Message + "\nPath: " + exePath + "\nArgs: " + args);
        }
    }

    IEnumerator WaitForMainWindowHandle()
    {
        if (webProcess == null)
            yield break;

        float timeout = 5f; // seconds
        float elapsed = 0f;
        while (elapsed < timeout)
        {
            try
            {
                webProcess.Refresh();
                if (webProcess.MainWindowHandle != IntPtr.Zero)
                {
                    Debug.Log($"WebViewLauncher: MainWindowHandle ready: 0x{webProcess.MainWindowHandle.ToInt64():X}");
                    WebViewReady?.Invoke();
                    yield break;
                }
            }
            catch (Exception e)
            {
                Debug.LogWarning("WebViewLauncher.WaitForMainWindowHandle exception: " + e.Message);
            }

            yield return null;
            elapsed += Time.deltaTime;
        }

        Debug.LogWarning("WebViewLauncher: timeout waiting for main window handle");
        // still invoke event so follower can attempt positioning later
        WebViewReady?.Invoke();
    }

    /// <summary>
    /// 从外部请求打开一个 url。如果 webview 没有运行则启动；如果已运行则尝试通过 WM_COPYDATA 发送 url 给已有窗口，失败则重启。
    /// 传入的 url 建议使用本地文件路径或以 file:// 开头的路径。
    /// </summary>
    /// <param name="url"></param>
    public void OpenUrl(string url)
    {
        if (string.IsNullOrEmpty(url))
        {
            Debug.LogWarning("OpenUrl called with empty url");
            return;
        }

        // Normalize to absolute file:// or keep as web URL
        string final;
        try
        {
            if (Uri.TryCreate(url, UriKind.Absolute, out var parsed) && !string.IsNullOrEmpty(parsed.Scheme))
            {
                // If it's already a file/http/https URI, use its AbsoluteUri
                final = parsed.AbsoluteUri;
            }
            else
            {
                // Treat as local file path
                string abs = Path.GetFullPath(url);
                final = new Uri(abs).AbsoluteUri; // yields file:///C:/...
            }
        }
        catch (Exception e)
        {
            Debug.LogWarning("OpenUrl: failed to normalize url '" + url + "' : " + e.Message);
            final = url;
        }

        Debug.Log($"OpenUrl requested. original='{url}', normalized='{final}'");
        startUrl = final;

        // if process not running, launch; otherwise try to send url to existing window
        if (webProcess == null || webProcess.HasExited)
        {
            Debug.Log("WebView process not running. Launching with URL: " + final);
            LaunchWebView();
            return;
        }

        try
        {
            Debug.Log($"WebView process running. PID={webProcess.Id}, MainWindowHandle=0x{webProcess.MainWindowHandle.ToInt64():X}");
        }
        catch { }

        // 尝试通过 WM_COPYDATA 将 URL 发送给已有进程窗口（需要 fdBrowser 实现接收处理）
        bool sent = WebViewWin32.TrySendUrlToWindow(webProcess, final);
        Debug.Log($"TrySendUrlToWindow returned: {sent}");
        if (sent)
        {
            Debug.Log("Sent URL to existing WebView process: " + final);
            // Notify followers that webview content may have changed and they should reapply positioning
            WebViewReady?.Invoke();
            return;
        }

        // 发送失败，退回到重启进程打开 URL 的方式
        Debug.Log("Failed to send URL to existing process, restarting to open: " + final);
        KillWebView();
        LaunchWebView();
        // after relaunch, WaitForMainWindowHandle will invoke WebViewReady when handle ready
    }

    string GetExePath()
    {
#if UNITY_EDITOR
        return Path.Combine(editorExeRoot, "fdBrowser.exe");
#else
        // 优先使用 StreamingAssets 路径
        string streamingPath = Path.Combine(Application.streamingAssetsPath, "fdBrowser", "fdBrowser.exe");
        if (File.Exists(streamingPath))
        {
            Debug.Log("Using StreamingAssets path: " + streamingPath);
            return streamingPath;
        }
        // 回退到游戏根目录
        string gameRoot = Path.GetDirectoryName(Application.dataPath);
        string fallbackPath = Path.Combine(gameRoot, "fdBrowser", "fdBrowser.exe");
        Debug.Log("Using fallback path: " + fallbackPath);
        return fallbackPath;
#endif
    }

    string GetH5FolderPath()
    {
#if UNITY_EDITOR
        return h5EditorPath;
#else
        return Path.Combine(Application.streamingAssetsPath, "h5LG");
#endif
    }

    System.Collections.Generic.List<string> ScanH5Folders(string folderPath)
    {
        var result = new System.Collections.Generic.List<string>();
        if (!Directory.Exists(folderPath))
        {
            Debug.LogWarning("H5 folder does not exist: " + folderPath);
            return result;
        }

        Debug.Log("Scanning H5 folders in: " + folderPath);
        string[] targetFolders = { officialDocsPath, officialGamesPath, thirdPartyGamesPath };
        foreach (string folderName in targetFolders)
        {
            string subFolderPath = Path.Combine(folderPath, folderName);
            if (!Directory.Exists(subFolderPath))
            {
                Directory.CreateDirectory(subFolderPath);
                Debug.Log("Created subfolder: " + subFolderPath);
            }

            string indexPath = Path.Combine(subFolderPath, "index.html");
            if (!File.Exists(indexPath))
            {
                File.WriteAllText(indexPath, "<html><body><h1>" + folderName + "</h1></body></html>");
                Debug.Log("Created index.html in: " + subFolderPath);
            }

            if (File.Exists(indexPath))
            {
                result.Add(folderName);
                Debug.Log("Found H5 folder with index.html: " + folderName);
            }
        }
        Debug.Log("Total H5 folders found: " + result.Count);
        return result;
    }

    /// <summary>
    /// 给 PanelFollower 调用
    /// </summary>
    public bool TryUpdateWebViewRect(int x, int y, int w, int h)
    {
        if (webProcess == null || webProcess.HasExited)
            return false;

        return WebViewWin32.TrySetWindowRect(webProcess, x, y, w, h);
    }
}