#if UNITY_EDITOR
using System;
using System.Reflection;
using UnityEditor;
using UnityEngine;
using UnityEngine.UIElements;
using UnityEditor.SceneManagement;

[InitializeOnLoad]
public static class PlaySpeedToolbar
{
    private const string ToolbarElementName = "PlaySpeedToolbar";
    private const double ToolbarCheckInterval = 0.25;

    private static readonly float[] Speeds = { 1f, 2f, 4f };

    private static VisualElement toolbarElement;
    private static double nextToolbarCheckTime;

    static PlaySpeedToolbar()
    {
        EditorApplication.update += OnEditorUpdate;
        EditorApplication.playModeStateChanged += OnPlayModeChanged;
        EditorApplication.delayCall += AddToolbarUI;
        AssemblyReloadEvents.afterAssemblyReload += OnAfterAssemblyReload;
    }

    private static void OnAfterAssemblyReload()
    {
        EditorApplication.delayCall += AddToolbarUI;
    }

    private static void OnPlayModeChanged(PlayModeStateChange state)
    {
        if (state == PlayModeStateChange.EnteredEditMode)
            Time.timeScale = 1f;

        EditorApplication.delayCall += AddToolbarUI;
    }

    private static void OnEditorUpdate()
    {
        EnsureToolbarExists();
    }

    private static void EnsureToolbarExists()
    {
        if (EditorApplication.timeSinceStartup < nextToolbarCheckTime)
            return;

        nextToolbarCheckTime = EditorApplication.timeSinceStartup + ToolbarCheckInterval;

        var toolbarType = typeof(Editor).Assembly.GetType("UnityEditor.Toolbar");
        if (toolbarType == null)
            return;

        var toolbars = Resources.FindObjectsOfTypeAll(toolbarType);
        if (toolbars == null || toolbars.Length == 0)
            return;

        foreach (var toolbar in toolbars)
        {
            TryInjectIntoToolbar(toolbarType, toolbar);
        }
    }

    private static void AddToolbarUI()
    {
        var toolbarType = typeof(Editor).Assembly.GetType("UnityEditor.Toolbar");
        if (toolbarType == null)
            return;

        var toolbars = Resources.FindObjectsOfTypeAll(toolbarType);
        if (toolbars == null || toolbars.Length == 0)
            return;

        foreach (var toolbar in toolbars)
        {
            TryInjectIntoToolbar(toolbarType, toolbar);
        }
    }

    private static void TryInjectIntoToolbar(Type toolbarType, UnityEngine.Object toolbar)
    {
        var rootField = toolbarType.GetField("m_Root", BindingFlags.NonPublic | BindingFlags.Instance);
        if (rootField == null)
            return;

        if (rootField.GetValue(toolbar) is not VisualElement root)
            return;

        // Центр тулбара, рядом с play/pause/stop
        var middleContainer = root.Q("ToolbarZonePlayMode");
        if (middleContainer == null)
            return;

        var existing = middleContainer.Q<IMGUIContainer>(ToolbarElementName);
        if (existing != null)
        {
            toolbarElement = existing;
            return;
        }

        var newElement = new IMGUIContainer(DrawGUI);
        newElement.name = ToolbarElementName;
        newElement.style.flexGrow = 0;
        newElement.style.flexShrink = 0;
        newElement.style.marginLeft = 6;
        newElement.style.marginRight = 2;
        newElement.style.minWidth = 118;
        newElement.style.maxWidth = 140;

        middleContainer.Add(newElement);
        toolbarElement = newElement;
    }

    private static void DrawGUI()
    {
        GUILayout.BeginHorizontal();

        // Bootstrap toggle
        bool bootstrapEnabled = SceneBootstrapLoader.Enabled;

        Color oldBg = GUI.backgroundColor;
        if (bootstrapEnabled)
            GUI.backgroundColor = new Color(0.72f, 0.84f, 1f);

        if (GUILayout.Button(
            new GUIContent("B", bootstrapEnabled ? "Bootstrap: ON" : "Bootstrap: OFF"),
            EditorStyles.miniButtonLeft,
            GUILayout.Width(24),
            GUILayout.Height(18)))
        {
            SceneBootstrapLoader.Enabled = !SceneBootstrapLoader.Enabled;

            if (!SceneBootstrapLoader.Enabled)
                EditorSceneManager.playModeStartScene = null;
        }

        GUI.backgroundColor = oldBg;

        bool isPlaying = EditorApplication.isPlaying;
        EditorGUI.BeginDisabledGroup(!isPlaying);

        for (int i = 0; i < Speeds.Length; i++)
        {
            float speed = Speeds[i];
            bool selected = Mathf.Approximately(Time.timeScale, speed);

            GUIStyle buttonStyle;
            if (i == Speeds.Length - 1)
                buttonStyle = EditorStyles.miniButtonRight;
            else
                buttonStyle = EditorStyles.miniButtonMid;

            oldBg = GUI.backgroundColor;
            if (selected)
                GUI.backgroundColor = new Color(0.72f, 0.84f, 1f);

            if (GUILayout.Button(
                new GUIContent($"{speed:0}x", $"Set Time.timeScale = {speed}"),
                buttonStyle,
                GUILayout.Width(24),
                GUILayout.Height(18)))
            {
                Time.timeScale = speed;
            }

            GUI.backgroundColor = oldBg;
        }

        EditorGUI.EndDisabledGroup();

        GUILayout.EndHorizontal();
    }
}
#endif