#if UNITY_EDITOR_WIN && UNITY_EDITOR

using System;
using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Text.RegularExpressions;
using UnityEditor;

[InitializeOnLoad]
public static class UnityEditorPerformanceBoost
{
    /// <summary>
    /// 現在ハイPerformanceModeか？
    /// </summary>
    private static bool isHighPerformance = false;

    /// <summary>
    /// 省電力電源プラン
    /// </summary>
    private static readonly string powerSchemeSaving = "a1841308-3541-4fab-bc81-f71556f20b4a";

    /// <summary>
    /// バランス電源プラン
    /// </summary>
    private static readonly string powerSchemeBalance = "381b4222-f694-41f0-9685-ff5bb260df2e";

    /// <summary>
    /// 高Performance電源プラン
    /// </summary>
    private static readonly string PowerSchemeHighPerformance = "8c5e7fda-e8bf-4a96-9a85-a6e23a8c635c";

    /// <summary>
    /// Timer
    /// </summary>
    private static double lastTime;

    /// <summary>
    /// 変更前の電源プラン
    /// </summary>
    private static string originalPowerScheme;

    /// <summary>
    /// GUID正規Table現
    /// </summary>
    private static readonly Regex GuidRegex = new(@"\b[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}\b", RegexOptions.Compiled);

    static UnityEditorPerformanceBoost()
    {
        EditorApplication.update += OnUpdate;
    }

    /// <summary>
    /// 定期Timer
    /// </summary>
    private static void OnUpdate()
    {
        if (EditorApplication.timeSinceStartup - lastTime > 2)
        {
            lastTime = EditorApplication.timeSinceStartup;
            CheckFocused();
        }
    }

    /// <summary>
    /// フォーカスチェック
    /// </summary>
    private static void CheckFocused()
    {
        if (IsWindowFocused())
        {
            EnableHighPerformance();
        }
        else
        {
            RestoreOriginalPowerScheme();
        }
    }

    /// <summary>
    /// ハイPerformanceModeを有効にする
    /// </summary>
    private static void EnableHighPerformance()
    {
        try
        {
            if (isHighPerformance) return;
            isHighPerformance = true;

            // 現在の電源プランをSave

            var str = CommandPowerCfg($"/getactivescheme");
            var match = GuidRegex.Match(str);
            originalPowerScheme = match.Value;

            // 自身のプロセス優先度を上げる

            Process.GetCurrentProcess().PriorityClass = ProcessPriorityClass.High;

            // Windowsの電源プランを高Performanceにする

            CommandPowerCfg($"/setactive {PowerSchemeHighPerformance}");

            UnityEngine.Debug.Log("高Performance電源プラン有効：" + PowerSchemeHighPerformance);
        }
        catch (Exception e)
        {
            UnityEngine.Debug.LogError(e);
        }
    }

    /// <summary>
    /// 元の電源プランに戻す
    /// </summary>
    private static void RestoreOriginalPowerScheme()
    {
        try
        {
            if (!isHighPerformance) return;
            isHighPerformance = false;

            // プロセス優先度を標準にする

            Process.GetCurrentProcess().PriorityClass = ProcessPriorityClass.Normal;

            // Windowsの電源プランを戻す

            CommandPowerCfg($"/setactive {originalPowerScheme}");

            UnityEngine.Debug.Log("元プランに戻した：" + originalPowerScheme);
        }
        catch (Exception e)
        {
            UnityEngine.Debug.LogError(e);
        }
    }

    [DllImport("user32.dll")]
    private static extern IntPtr GetForegroundWindow();

    [DllImport("user32.dll")]
    private static extern uint GetWindowThreadProcessId(IntPtr hWnd, out uint processId);

    /// <summary>
    /// ウィンドウが前面に出ているか？
    /// </summary>
    /// <returns></returns>
    private static bool IsWindowFocused()
    {
        IntPtr hwnd = GetForegroundWindow();
        if (hwnd == IntPtr.Zero) return false;

        GetWindowThreadProcessId(hwnd, out uint processId);
        return (processId == (uint)Process.GetCurrentProcess().Id);
    }

    /// <summary>
    /// 電源プランコマンド
    /// </summary>
    /// <param name="command"></param>
    /// <returns></returns>
    private static string CommandPowerCfg(string command)
    {
        var processStartInfo = new ProcessStartInfo("powercfg", command)
        {
            RedirectStandardOutput = true,
            UseShellExecute = false,
            CreateNoWindow = true
        };

        using (var process = Process.Start(processStartInfo))
        {
            return process.StandardOutput.ReadToEnd();
        }
    }
}

#endif