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

namespace RunlevelSystems.DevPlus1.EditorTools
{
    public static class RLUnityEventAnalyzer
    {
        public static List<RLUnityEventInfo> ExtractUnityEvents(GameObject gameObject, string sourcePath, string hierarchyPath)
        {
            List<RLUnityEventInfo> events = new List<RLUnityEventInfo>();
            Component[] components = gameObject.GetComponents<Component>();

            foreach (Component component in components)
            {
                if (component == null)
                {
                    continue;
                }

                SerializedObject serializedObject = new SerializedObject(component);
                SerializedProperty iterator = serializedObject.GetIterator();
                bool enterChildren = true;

                while (iterator.NextVisible(enterChildren))
                {
                    enterChildren = false;
                    if (iterator.propertyType == SerializedPropertyType.Generic &&
                        (iterator.type.Contains("UnityEvent") || iterator.displayName.Contains("On Click") || iterator.name.Contains("m_OnClick")))
                    {
                        ExtractPersistentCalls(events, iterator.Copy(), sourcePath, hierarchyPath, component);
                    }
                }
            }

            return events;
        }

        private static void ExtractPersistentCalls(List<RLUnityEventInfo> events, SerializedProperty eventProperty, string sourcePath, string hierarchyPath, Component component)
        {
            SerializedProperty calls = eventProperty.FindPropertyRelative("m_PersistentCalls.m_Calls");
            if (calls == null || !calls.isArray)
            {
                return;
            }

            for (int i = 0; i < calls.arraySize; i++)
            {
                SerializedProperty call = calls.GetArrayElementAtIndex(i);
                Object target = ReadObject(call, "m_Target");
                string method = ReadString(call, "m_MethodName");

                RLUnityEventInfo info = new RLUnityEventInfo();
                info.sourcePath = sourcePath;
                info.gameObjectPath = hierarchyPath;
                info.componentName = component.GetType().Name;
                info.eventName = eventProperty.displayName;
                info.targetObject = target != null ? target.name : "missing or none";
                info.targetComponent = target != null ? target.GetType().Name : "not detected";
                info.targetMethod = string.IsNullOrEmpty(method) ? "not detected" : method;
                events.Add(info);
            }
        }

        private static Object ReadObject(SerializedProperty parent, string relativePath)
        {
            SerializedProperty property = parent.FindPropertyRelative(relativePath);
            return property != null ? property.objectReferenceValue : null;
        }

        private static string ReadString(SerializedProperty parent, string relativePath)
        {
            SerializedProperty property = parent.FindPropertyRelative(relativePath);
            return property != null ? property.stringValue : string.Empty;
        }
    }
}