using System.Collections;
using System.Collections.Generic;
using Unity.VisualScripting;
using UnityEngine;
using UnityEngine.UI;
using UnityEngine.UIElements;

public class MenuController : MonoBehaviour
{
    // Start is called once before the first execution of Update after the MonoBehaviour is created
    private VisualElement mainMenu;
    private List<VisualElement> subMenus = new();
    bool isSubMenuShow = false;
    void Start()
    {
        var root = GetComponent<UIDocument>().rootVisualElement;
        var menuArea = root.Q<VisualElement>("menuArea");
        mainMenu = menuArea.Q<VisualElement>("mainMenu");
        var home = menuArea.Q<VisualElement>("home");
        subMenus.Add(home);
        var playground = menuArea.Q<VisualElement>("playground");
        subMenus.Add(playground);
        var shop = menuArea.Q<VisualElement>("shop");
        subMenus.Add(shop);
        var warehouse = menuArea.Q<VisualElement>("warehouse");
        subMenus.Add(warehouse);
        var cameraBtn = menuArea.Q<VisualElement>("camera");
        subMenus.Add(cameraBtn);
        var status = menuArea.Q<VisualElement>("status");
        subMenus.Add(status);

        mainMenu.RegisterCallback<ClickEvent>(e => MainMenuClick(e));
        // root加载完成后，所有element算出位置后再进行计算
        root.RegisterCallback<GeometryChangedEvent>(e => OnMainMenuClickGeometryChanged(e));
    }

    // Update is called once per frame
    void Update()
    {
        
    }

    Vector2 CalcPosition (Vector2 curPosition, float angle, float distance)
    {
        float radians = angle * Mathf.Deg2Rad;
        float x = curPosition.x + distance * Mathf.Cos(radians);
        float y = curPosition.y - distance * Mathf.Sin(radians);
        Vector2 newPosition = new Vector2(x, y);
        return new Vector2(x, y);
    }

    // 初始化所有按键的位置
    void InitialSubMenu()
    {
        foreach (var subMenu in subMenus) {
            subMenu.style.left = mainMenu.resolvedStyle.left;
            subMenu.style.top = mainMenu.resolvedStyle.top;
            subMenu.visible = false;
        }
    }

    // 点击主按键后所有子按键展开并显示
    void MainMenuClick(ClickEvent evt)
    {
        if (isSubMenuShow)
        {
            MenuReset();
            isSubMenuShow = false;
            return;
        }
        // curAngle 初始角度，angleDelta 2个子菜单之间角度，distance 弹出距离，showTimer 显示时间
        float curAngle = 75f;
        float angleDelta = 40f;
        float distance = 70f;
        float showTimer = 3.0f;
        foreach (var subMenu in subMenus) {
            subMenu.visible = true;
            var newPosition = CalcPosition(mainMenu.layout.position, curAngle, distance);
            //subMenu.layout.position.Set(newPosition.x, newPosition.y);
            subMenu.style.left = newPosition.x;
            subMenu.style.top = newPosition.y;
            curAngle += angleDelta;
        }
        mainMenu.transform.scale = new Vector2(0.8f, 0.8f);
        Invoke("MenuReset", showTimer);
        isSubMenuShow = true;
    }

    // 初始化后屏幕尺寸变化时候调用。在此处应用于第一次屏幕初始化完成。
    void OnMainMenuClickGeometryChanged(GeometryChangedEvent evt) {
        //VisualElement targetElement = evt.target as VisualElement;
        InitialSubMenu();
    }

    void MenuReset()
    {
        //yield return new WaitForSeconds(3.0f);
        mainMenu.transform.scale = new Vector2(1.0f, 1.0f);
        InitialSubMenu();
    }
}