3DTD/Assets/Scripts/PlacementSystem/PlacementManager.cs

using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using Unity.Mathematics;
using Unity.VisualScripting;
using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.UI;

public class TowerPlacementManager : MonoBehaviour
{
    public static TowerPlacementManager Instance;

    // Spawning grid events
    public static event Action<TowerPlacementManager> OnSpawnGridRequested;
    public static event Action<TowerPlacementManager> OnGridDeleteRequested;

    // Placing tower
    public static event Action<TowerInfo> OnTowerPlaced;


    [Header("Debug")]
    [SerializeField] private bool RebuildGrid = false;

    // Section: Mouse
    private SlotManager CurrentSelectedSlot;

    private int CurrentRotation = 0; // 0, 1, 2, 3

    private GameObject SilhouettedObject;
    private TowerInfo SelectedTowerInfo;

    private GameObject SelectedTowerPrefab => SelectedTowerInfo.prefab;

    private void Start()
    {
        if (Instance != this)
            Destroy(Instance);
        Instance = this;

        OnSpawnGridRequested?.Invoke(this);
    }

    private void Update()
    {
        if (Input.GetKeyDown(KeyCode.R) && Input.GetKey(KeyCode.LeftShift))
        {
            CurrentRotation--;
            CurrentRotation = CurrentRotation % 4;
        }
        else if (Input.GetKeyDown(KeyCode.R))
        {
            CurrentRotation++;
            CurrentRotation = CurrentRotation % 4;
        }

        if (RebuildGrid)
        {
            RebuildGrid = false;
            OnGridDeleteRequested?.Invoke(this);
            OnSpawnGridRequested?.Invoke(this);
        }
    }

    private void OnEnable()
    {
        OnTowerPlaced += PlayPlaceSfx;
        MoneyManager.OnShopSelected += OnShopSelected;
    }

    private void OnDisable()
    {
        OnTowerPlaced -= PlayPlaceSfx;
        MoneyManager.OnShopSelected -= OnShopSelected;
    }

    private void PlayPlaceSfx(TowerInfo info)
    {
        AudioManager.PlaySound("Build Tower", Vector3.zero);
    }

    private void OnShopSelected(TowerInfo info)
    {
        SelectedTowerInfo = info;
        Destroy(SilhouettedObject);
    }

    public void OnSlotClicked(SlotManager slot, GridManager grid, int x, int y)
    {
        if (GameManager.Instance.Balance.Value < SelectedTowerInfo.price) return; // cant afford

        // slot.gameObject.GetComponentInChildren<Renderer>().material.color = Color.blue;
        OnSelectSlot(slot);

        SpawnTowerAtSelected(slot, SelectedTowerPrefab);
        GameManager.Instance.Balance.Value -= SelectedTowerInfo.price;
    }

    // Called when a slot is selected
    public void OnSelectSlot(SlotManager slot)
    {
        // Detects if the selected slot is new
        if (CurrentSelectedSlot != null && CurrentSelectedSlot != slot)
            OnDeselectSlot(CurrentSelectedSlot, slot);
        CurrentSelectedSlot = slot;

        slot.gameObject.GetComponentInChildren<Renderer>().material.color = default;
    }

    // Called when another slot is getting selected
    public void OnDeselectSlot(SlotManager prevSlot, SlotManager newSlot)
    {
        prevSlot.gameObject.GetComponentInChildren<Renderer>().material.color = Color.white;
    }

    public void SpawnTowerAtSelected(SlotManager slotRef, GameObject towerPrefab)
    {
        var spawnedTower = Instantiate(towerPrefab, CurrentSelectedSlot.transform);
        Quaternion newRotation = Quaternion.AngleAxis(CurrentRotation * 90f, transform.up);
        spawnedTower.transform.localRotation = newRotation;

        Tower towerScript = spawnedTower.GetComponent<Tower>();

        slotRef.TowerHealth = towerScript.GetComponent<HealthComponent>();

        towerScript.Placed();
        FinishBuild();
    }

    public void OnSlotHovered(SlotManager slot, GridManager grid, int x, int y)
    {
        if (SilhouettedObject == null)
            SilhouettedObject = ToSilhouette(SelectedTowerPrefab);

        // Sets tower rotation
        Quaternion newRotation = Quaternion.AngleAxis(CurrentRotation * 90f, transform.up);
        SilhouettedObject.transform.localRotation = newRotation;

        Vector3 offset = SelectedTowerPrefab.transform.position;

        //SilhouettedObject.SetActive(true);
        SilhouettedObject.transform.parent = slot.TowerSpawnPoint.transform;
        SilhouettedObject.transform.localPosition = offset;

        slot.gameObject.GetComponentInChildren<Renderer>().material.color = Color.white;
    }

    public void OnSlotUnHovered(SlotManager slot, GridManager grid, int x, int y)
    {
        slot.gameObject.GetComponentInChildren<Renderer>().material.color = default;
        Destroy(SilhouettedObject);
    }

    public void FinishBuild()
    {
        Destroy(SilhouettedObject);
        OnTowerPlaced?.Invoke(SelectedTowerInfo);
    }


    [Space(10)]
    public Material SilhouetteMaterial;
    public GameObject ToSilhouette(GameObject obj)
    {
        // if prefab, then spawn it
        if (obj.scene.name == null)
            obj = Instantiate(obj);

        Component[] objScripts = obj.GetComponents<Component>();
        objScripts = objScripts.Concat(obj.GetComponentsInChildren<Component>()).ToArray();

        for (int i = 0; i < objScripts.Length; i++)
        {
            var comp = objScripts[i];

            if (comp is not Renderer && comp is not Transform && comp is not MeshFilter && comp is not UIBehaviour)
            {
                Destroy(comp);
            }
            else if (typeof(Renderer).IsAssignableFrom(comp))
            {
                var renderer = comp as Renderer;
                renderer.materials = new Material[] { SilhouetteMaterial , SilhouetteMaterial , SilhouetteMaterial , SilhouetteMaterial , SilhouetteMaterial };
            }
        }

        return obj;
    }
}