using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using Sirenix.OdinInspector;
using UniRx;
using KairoEngine.Core;

namespace KairoEngine.Core.GameActions
{
    [System.Serializable]
    public class GameActionsController : ISerializationCallbackReceiver
    {
        /// <summary>A context object that holds a list of GameActionContextVariables to be accessible for GameActions to use.</summary>
        [InlineProperty, HideLabel, ShowIf("showContext")]
        public GameActionContext context = new GameActionContext();

        [HideInInspector] public bool showContext = false;

        /// <summary>A list of GameActions to be executed in order.</summary>
        [ListDrawerSettings(HideAddButton = true, HideRemoveButton = false, DraggableItems = true, Expanded = false, ShowPaging = false, ShowItemCount = true)]
        [ShowInInspector, NonSerialized, OnInspectorInit("InitializeActionList")]
        [Space(4)]
        public List<GameAction> actions = new List<GameAction>();

        [NonSerialized] private CompositeDisposable cancel;
        private int actionIndex = 0;

        public bool started => _started;
        public bool isDone => _done;
        private bool _started = false;
        private bool _done = false;

        [HideInInspector] public int depth = 0;

        #region FlowControl

        /// <summary>Run GameActions on this controller. Each action will be fired after the previous action ended.</summary>
        public void Start()
        {
            actionIndex = 0;
            _done = false;
            _started = true;
            var observable = Observable.EveryUpdate();
            cancel = new CompositeDisposable();
            observable.Subscribe(xs => ExecuteActions()).AddTo(cancel);
        }

        /// <summary>Executes GameActions until it has to wait for an Update or reach the end of the action list.</summary>
        private void ExecuteActions()
        {
            if(actionIndex >= actions.Count)
            {
                // done
                _done = true;
                cancel.Dispose();
                return;
            }
            if(actions[actionIndex].done) 
            {
                actionIndex += 1;
                ExecuteActions();
            }
            else 
            {
                if(actions[actionIndex].started == false)
                {
                    actions[actionIndex].Start();
                    ExecuteActions();
                }
                else actions[actionIndex].Update();
            }
        }

        /// <summary>Stop executing GameActions on this controller.</summary>
        public void Stop()
        {
            if(cancel != null) cancel.Dispose();
        }

        public void Restart()
        {
            actionIndex = 0;
            _started = false;
            _done = false;
            foreach (var action in actions) action.Restart();
        }

        #endregion

        #region Serialization

        [SerializeField, HideInInspector] private List<string> serializedActions = new List<string>();
        [SerializeField, HideInInspector] public GameActionObjectSerializer objectSerializer = new GameActionObjectSerializer();

        private void SerializeActions()
        {
            if(actions == null) return;
            serializedActions = new List<string>();
            objectSerializer.ClearGameObjects();
            objectSerializer.ClearScriptableObjects();
            for (int i = 0; i < actions.Count; i++)
            {
                actions[i].OnBeforeSerialize(objectSerializer, i, depth);
                string data = JsonUtility.ToJson(actions[i]);
                serializedActions.Add(data);
            }
        }

        private void DeserializeActions()
        {
            if(serializedActions == null) return;
            if(actions == null) actions = new List<GameAction>();
            if(actions.Count > 0) actions.Clear();
            for (int i = 0; i < serializedActions.Count; i++)
            {
                GameAction action = JsonUtility.FromJson<GameActionBase>(serializedActions[i]);
                action = GameAction.InvokeStringMethod(action.className, action.typeName, serializedActions[i]);
                action.controller = this;
                action.OnBeforeDeserialize(objectSerializer, i, depth);
                actions.Add(action);
                // Type t = Type.GetType(action.typeName);
                // dynamic obj = Convert.ChangeType(action, t);
                // if(obj != null) actions.Add(obj.Duplicate());
                // else if(action != null) actions.Add(action);
            }
            for (int i = 0; i < actions.Count; i++)
            {
                actions[i].Initialize(objectSerializer);
            }
            objectSerializer.ClearGameObjects();
            objectSerializer.ClearScriptableObjects();
            //serializedActions = new List<string>();
        }

        public void OnBeforeSerialize() => SerializeActions();
        public void OnAfterDeserialize() => DeserializeActions();

        #endregion

        #region NewAction

        [OnInspectorInit("GetCompatibleVariablenames"), OnValueChanged("AddNewAction")]
        [ValueDropdown("possibleActions", IsUniqueList = false)]
        [LabelText("Add New Action")]
        [NonSerialized]
        public GameAction newAction;

        [NonSerialized] private IEnumerable possibleActions = new ValueDropdownList<GameAction>();

        private void GetCompatibleVariablenames()
        {
            possibleActions = ReflectiveEnumerator.GetEnumerableOfType<GameAction>(this)
                .Where(x => x.GetTypeName() != "GameActionBase")
                .Where(x => x.GetTypeName() != "GameAction")
                .Select(x => new ValueDropdownItem(x.GetActionName(), x));
        }

        private void AddNewAction()
        {
            if(newAction != null)
            {
                newAction.controller = this;
                newAction.className = newAction.GetType().AssemblyQualifiedName;
                actions.Add(newAction);
                newAction = null;
            }
        }

        #endregion
    
        #region Utilities

        private void InitializeActionList()
        {
            if(actions == null) actions = new List<GameAction>();
        }

        public GameActionsController Duplicate()
        {
            GameActionsController newController = new GameActionsController();
            newController.actions = new List<GameAction>();
            var newSerializedActions = new List<string>();
            objectSerializer.ClearGameObjects();
            for (int i = 0; i < actions.Count; i++)
            {
                actions[i].OnBeforeSerialize(objectSerializer, i, depth);
                string data = JsonUtility.ToJson(actions[i]);
                newSerializedActions.Add(data);
            }
            newController.objectSerializer = objectSerializer;
            objectSerializer = new GameActionObjectSerializer();
            newController.context = this.context.Duplicate();
            for (int i = 0; i < newSerializedActions.Count; i++)
            {
                //Debug.Log(newSerializedActions[i]);
                GameAction action = JsonUtility.FromJson<GameActionBase>(newSerializedActions[i]);
                if(action == null) continue;
                action = GameAction.InvokeStringMethod(action.className, action.typeName, newSerializedActions[i]);
                action.controller = newController;
                action.OnBeforeDeserialize(newController.objectSerializer, i, depth);
                newController.actions.Add(action);
            }
            newController.objectSerializer.ClearGameObjects();
            return newController;
        }

        #endregion
    }
}