XRLib/Assets/Scripts/UVC/UIToolkit/Property/Items/UTKDropdownPropertyItem.cs

#nullable enable
using System;
using System.Collections.Generic;
using System.Linq;
using UnityEngine.UIElements;

namespace UVC.UIToolkit.Property
{
    /// <summary>
    /// 드롭다운 목록 속성 아이템
    /// 문자열 리스트에서 선택
    /// </summary>
    public class UTKDropdownPropertyItem : UTKPropertyItemBase<string>
    {
        #region Fields
        private DropdownField? _dropdown;
        private List<string> _choices;
        #endregion

        #region Properties
        public override UTKPropertyType PropertyType => UTKPropertyType.DropdownList;

        /// <summary>선택 가능한 항목 목록</summary>
        public List<string> Choices
        {
            get => _choices;
            set
            {
                _choices = value ?? new List<string>();
                if (_dropdown != null)
                {
                    _dropdown.choices = _choices;
                }
            }
        }
        #endregion

        #region Constructor
        public UTKDropdownPropertyItem(string id, string name, List<string> choices, string initialValue = "")
            : base(id, name, initialValue)
        {
            _choices = choices ?? new List<string>();

            // initialValue가 choices에 없으면 첫 번째 항목 선택
            if (!string.IsNullOrEmpty(initialValue) && !_choices.Contains(initialValue) && _choices.Count > 0)
            {
                Value = _choices[0];
            }
        }

        public UTKDropdownPropertyItem(string id, string name, IEnumerable<string> choices, int selectedIndex = 0)
            : base(id, name, string.Empty)
        {
            _choices = choices?.ToList() ?? new List<string>();

            if (_choices.Count > 0 && selectedIndex >= 0 && selectedIndex < _choices.Count)
            {
                Value = _choices[selectedIndex];
            }
            else if (_choices.Count > 0)
            {
                Value = _choices[0];
            }
        }
        #endregion

        #region Override Methods
        public override VisualElement CreateUI()
        {
            var container = CreateContainer();

            var label = CreateNameLabel();
            container.Add(label);

            var valueContainer = new VisualElement();
            valueContainer.AddToClassList("utk-property-item__value");

            int selectedIndex = _choices.IndexOf(Value);
            _dropdown = new DropdownField(_choices, Math.Max(0, selectedIndex));
            _dropdown.name = "dropdown-field";
            valueContainer.Add(_dropdown);

            container.Add(valueContainer);

            return container;
        }

        public override void BindUI(VisualElement element)
        {
            base.BindUI(element);

            _dropdown = element.Q<DropdownField>("dropdown-field");

            if (_dropdown != null)
            {
                _dropdown.choices = _choices;
                int selectedIndex = _choices.IndexOf(Value);
                _dropdown.index = Math.Max(0, selectedIndex);
                _dropdown.SetEnabled(!IsReadOnly);
                _dropdown.RegisterValueChangedCallback(OnDropdownChanged);
            }
        }

        public override void UnbindUI(VisualElement element)
        {
            if (_dropdown != null)
            {
                _dropdown.UnregisterValueChangedCallback(OnDropdownChanged);
                _dropdown = null;
            }

            base.UnbindUI(element);
        }

        public override void RefreshUI()
        {
            if (_dropdown != null && _dropdown.value != Value)
            {
                _dropdown.SetValueWithoutNotify(Value);
            }
        }

        protected override void UpdateReadOnlyState()
        {
            base.UpdateReadOnlyState();

            if (_dropdown != null)
            {
                _dropdown.SetEnabled(!IsReadOnly);
            }
        }
        #endregion

        #region Public Methods
        /// <summary>선택 항목 추가</summary>
        public void AddChoice(string choice)
        {
            if (!_choices.Contains(choice))
            {
                _choices.Add(choice);
                if (_dropdown != null)
                {
                    _dropdown.choices = _choices;
                }
            }
        }

        /// <summary>선택 항목 제거</summary>
        public bool RemoveChoice(string choice)
        {
            bool removed = _choices.Remove(choice);
            if (removed && _dropdown != null)
            {
                _dropdown.choices = _choices;

                // 현재 선택 값이 제거되면 첫 번째 항목 선택
                if (Value == choice && _choices.Count > 0)
                {
                    Value = _choices[0];
                }
            }
            return removed;
        }
        #endregion

        #region Private Methods
        private void OnDropdownChanged(ChangeEvent<string> evt)
        {
            Value = evt.newValue;
        }
        #endregion
    }
}