using UnityEditor;
using UnityEngine;
using UnityForge.PropertyDrawers.Editor;

namespace KitsuneCafe.Editor.PropertyDrawers
{
  public abstract class ComponentObjectFieldPropertyDrawer<TAttribute, TObject> : PropertyDrawer
      where TAttribute : PropertyAttribute
      where TObject : Object
  {
    private SerializedPropertyType propertyType_;

    protected ComponentObjectFieldPropertyDrawer(SerializedPropertyType propertyType)
    {
      propertyType_ = propertyType;
    }

    public override void OnGUI(Rect position, SerializedProperty property, GUIContent label)
    {
      position = EditorGUI.PrefixLabel(position, label);

      if (property.propertyType != propertyType_)
      {
        EditorGUI.LabelField(position, string.Format("Error: {0} attribute can be applied only to {1} type", typeof(TAttribute), propertyType_));
        return;
      }

      var field = GetPropertyPath((TAttribute)attribute);
      if (!string.IsNullOrEmpty(field))
      {
        ObjectFieldPropertyDrawerUtils.DrawObjectFieldPoperty<TObject>(
            position, property, field, DrawComponentProperty);
        return;
      }

      var targetObject = property.serializedObject.targetObject as TObject;
      if (targetObject == null)
      {
        EditorGUI.LabelField(position, "Error: inspected object type is not an Object");
        return;
      }

      DrawComponentProperty(position, property, targetObject);
    }

    protected abstract string GetPropertyPath(TAttribute attribute);

    protected abstract void DrawComponentProperty(Rect position, SerializedProperty property, TObject target);
  }
}