using System.Collections;
using Unity.VisualScripting;
using UnityEngine;
using UnityEngine.AI;
using UnityEngine.Events;

public enum UnitState
{
    Idle,
    Move,
    MoveToResource,
    Gather
}

public class Unit : MonoBehaviour
{
    [Header("Components")]
    public GameObject selectionVisual;
    private NavMeshAgent navAgent;
    private SelectionMarker selectionMarker;
    [Header("Stats")]
    public UnitState state;
    public int gatherAmount;
    public float gatherRate;
    private float lastGatherTime;
    private ResourceSource resource;
    //events
    public class StateChangeEvent : UnitEvent<UnitState> { }
    public StateChangeEvent onStateChange;
    public Player player;

    void Awake()
    {
        //get the components
        navAgent = GetComponent<NavMeshAgent>();
    }
    // Start is called once before the first execution of Update after the MonoBehaviour is created
    void Start()
    {

    }

    // Update is called once per frame
    void Update()
    {
        if (selectionMarker != null && !navAgent.pathPending && navAgent.remainingDistance <= navAgent.stoppingDistance)
        {
            selectionMarker.DestroySelectionMarker();
            selectionMarker = null;
        }
        switch(state)
        {
            case UnitState.Move
            {
                MoveUpdate();
                break;
            }
            case UnitState.MoveToResource
            {
                MoveToResourceUpdate();
                break;
            }
            case UnitState.Gather
            {
                GatherUpdate();
                break;
            }
        }
    }
    public void ToggleSelectionVisual(bool selected)
    {
        selectionVisual.SetActive(selected);
    }
    public void MoveToPosition(Vector3 pos, SelectionMarker marker = null)
    {
        if (selectionMarker != null)
        {
            selectionMarker.DestroySelectionMarker();
            selectionMarker = null;
        }
        navAgent.isStopped = false;
        navAgent.SetDestination(pos);
        selectionMarker = marker;
    }
    //move to a resource and begin to gather it
    public void GatherResource(ResourceSource resource, Vector3 pos)
    {
        
    }
    void SetState(UnitState toState)
    {
        state = toState;
        //calling the event
        if(onStateChange != null)
            onStateChange.Invoke(state);
        if(toState == UnitState.Idle)
        {
            navAgent.isStopped = true;
            navAgent.ResetPath();
        }
    }
    void MoveUpdate()
    {
        
    }
    void MoveToResourceUpdate()
    {
        
    }
    void GatherUpdate()
    {
        
    }
}