using System;
using Opsive.UltimateCharacterController.Camera;
using Opsive.UltimateCharacterController.Character.MovementTypes;
using Opsive.UltimateCharacterController.Utility.Builders;
using Redcode.Awaiting;
using SoftKitty.MasterCharacterCreator;
using UnityEngine;

namespace Plantaria.PlayerSystem
{
    /// <summary>
    /// Dynamically builds the character for use with Ultimate Character Controller and Master Character Creator.
    /// </summary>
    /// <remarks>
    /// There's a lot of hard-coded null/false arguments when invoking the builder methods.
    /// This is specifically for the Third Person Controller with minimal extras.
    /// If you need more features or wish to use the First Person perspective,
    /// you'll need to add them in by implementing more fields.
    ///
    /// Place this on the same GameObject as your CharacterEntity GameObject.
    /// Note: I added a property called InstantiationRoot to CharacterEntity.cs, which
    /// simply parents the instantiated prefab beneath a specified Transform instead of the root.
    /// </remarks>
    public class ThirdPersonCharacterRuntimeBuilder : MonoBehaviour
    {
        private GameObject _SpawnedCharacter => _characterEntity.InstantiationRoot.GetChild(0).gameObject;

        [SerializeField] private CameraController _cameraController;
        [SerializeReference] private MovementType _movementType;

        private CharacterEntity _characterEntity;
        private GameObject _character;
        private Animator _animator;

        private void Reset()
        {
            _cameraController = FindFirstObjectByType<CameraController>();
        }

        private void Awake()
        {
            if (!CanBuild()) throw new InvalidOperationException("Character cannot be built.");

            _characterEntity = GetComponent<CharacterEntity>();
            _animator = GetComponent<Animator>();
            _character = this.gameObject;
        }

        private bool CanBuild()
        {
            if (_cameraController.InitCharacterOnAwake)
            {
                Debug.LogError("Character should not be initialized on awake. This will be done at runtime after the character entity has been instantiated.");
                return false;
            }

            return true;
        }

        private async void Start()
        {
            // Wait until the character entity has been instantiated.
            // TODO: This should probably have a time-out
            await new WaitUntil(() => _SpawnedCharacter != null);

            // Reference the animation controller in the Animator component. This is set by CharacterEntity.
            var animatorControllers = new[] { _animator.runtimeAnimatorController };

            CharacterBuilder.BuildCharacter(
                character: _character,
                characterModels: new[] { _SpawnedCharacter },
                addAnimator: true,
                animatorControllers,
                firstPersonMovementType: string.Empty,
                thirdPersonMovementType: _movementType.GetType().FullName,
                startFirstPersonPerspective: false,
                thirdPersonObjects: Array.Empty<GameObject[]>(),
                invisibleShadowCasterMaterial: null,
                aiAgent: false
            );

            TransferAnimatorToSpawnedCharacter();

            CharacterBuilder.BuildCharacterComponents(
                character: _character,
                aiAgent: false,
                addItems: false,
                itemCollection: null,
                itemSetRule: null,
                firstPersonItems: false,
                addHealth: false,
                addUnityIK: true,
                addFootEffects: true,
                addStandardAbilities: true,
                addNavMeshAgent: false
            );

            // The setter for this property calls InitializeCharacter, which will link the CameraController to the Character
            _cameraController.Character = _character;
        }

        private void TransferAnimatorToSpawnedCharacter()
        {
            // Copy the existing Animator over to the newly spawned character prefab
            var newAnimator = _SpawnedCharacter.GetComponent<Animator>();
            newAnimator.avatar = _animator.avatar;
            newAnimator.runtimeAnimatorController = _animator.runtimeAnimatorController;

            // Destroy the old Animator since it's no longer used
            Destroy(_animator);
        }
    }
}