using System.Collections.Generic;
using UnityEngine;
using UnityEditor;
using YKMoon;

namespace YKMoonEditor
{
    [CustomPropertyDrawer(typeof(MonoBehaviourProperty))]
    public class PDrawer_MonoBehaviourProperty : PropertyDrawer
    {
        Vector2Int contentSize = new Vector2Int(2, 2);//2x2
        Vector2 contentSpace = new Vector2(4, 2);
        Vector2 padding = new Vector2(4, 1);
        float rowHeight = 18f;
        public override float GetPropertyHeight(SerializedProperty property, GUIContent label)
        {
            return contentSize.y * (rowHeight + contentSpace.y) + padding.y * 2;
        }

        public override void OnGUI(Rect position, SerializedProperty property, GUIContent label)
        {
            EditorGUI.BeginProperty(position, label, property);
            //properties
            var p_go = property.FindPropertyRelative("go");
            var p_mono = property.FindPropertyRelative("monoBehaviour");

            var contentRect = new Rect(position.x, position.y, position.width, position.height);
            int index = 0;
            //MonoBehaviour
            using(new EditorGUI.DisabledScope(true)) {
                var rect = UEditorUtility.SplitRect(contentRect, contentSize, contentSpace, index++, padding);
                EditorGUI.PropertyField(new Rect(contentRect.x, contentRect.y, contentRect.width, rect.height), p_mono, GUIContent.none);
                index++;
            }
            //gameobject
            {
                var rect = UEditorUtility.SplitRect(contentRect, contentSize, contentSpace, index++, padding);
                EditorGUI.PropertyField(rect, p_go, GUIContent.none);
            }
            //MonoBehaviour selection
            {
                var rect = UEditorUtility.SplitRect(contentRect, contentSize, contentSpace, index++, padding);
                var newValue = DrawMonoBehaviourSelectPopup(p_go.objectReferenceValue as GameObject, rect, p_mono.objectReferenceValue as MonoBehaviour);
                if(newValue != p_mono.objectReferenceValue) {
                    p_mono.objectReferenceValue = newValue;
                }
            }

            EditorGUI.EndProperty();
        }

        #region Tool
        /// <summary>
        /// Ãè»æMonoBehaviourµ¯³ö¿ò
        /// </summary>
        private MonoBehaviour DrawMonoBehaviourSelectPopup(GameObject go, Rect rect, MonoBehaviour selectedType)
        {
            var monos = GetMonoBehaviours(go);
            var monoStrings = GetMonoBehaviourString(monos);
            int index = monos.IndexOf(selectedType);
            index = EditorGUI.Popup(rect, index, monoStrings.ToArray());
            if(index >= 0) {
                return monos[index];
            } else {
                return go == null ? null : monos[0];
            }
        }
        private List<string> GetMonoBehaviourString(List<MonoBehaviour> componnents)
        {
            List<string> result = new List<string>();
            for(int i = 0; i < componnents.Count; i++) {
                if(componnents[i] == null) {
                    result.Add("Null");
                } else {
                    result.Add(componnents[i].GetType().ToString());
                }
            }
            return result;
        }
        private List<MonoBehaviour> GetMonoBehaviours(GameObject obj)
        {
            List<MonoBehaviour> monos = new List<MonoBehaviour>();
            if(obj != null) {
                var components = ListPool<Component>.Get();
                obj.GetComponents(typeof(MonoBehaviour), components);
                foreach(var comp in components) {
                    if (comp is MonoBehaviour) {
                        monos.Add(comp as MonoBehaviour);
                    }
                }
                ListPool<Component>.Release(components);
            }
            //componnents.Insert(0, null);
            return monos;
        }
        #endregion  
    }
}