Northbound/Assets/Scripts/DamageableNetworkBehaviour.cs

using System;
using Unity.Netcode;
using UnityEngine;

namespace Northbound
{
    public abstract class DamageableNetworkBehaviour : NetworkBehaviour, IDamageable
    {
        [Header("Health Settings")]
        [SerializeField] protected int maxHealth = 100;
        [SerializeField] protected bool showHealthBar = true;

        [Header("Visual Effects")]
        [SerializeField] protected GameObject damageEffectPrefab;
        [SerializeField] protected GameObject destroyEffectPrefab;
        [SerializeField] protected Transform effectSpawnPoint;

        protected NetworkVariable<int> _currentHealth = new NetworkVariable<int>(
            0,
            NetworkVariableReadPermission.Everyone,
            NetworkVariableWritePermission.Server
        );

        public event Action<int, int> OnHealthChanged;
        public event Action OnDestroyed;

        protected void InvokeOnHealthChanged(int currentHealth, int maxHealth)
        {
            OnHealthChanged?.Invoke(currentHealth, maxHealth);
        }

        protected void InvokeOnDestroyed()
        {
            OnDestroyed?.Invoke();
        }

        public override void OnNetworkSpawn()
        {
            base.OnNetworkSpawn();

            if (IsOwner)
            {
                InitializeHealthServerRpc(maxHealth);
            }

            _currentHealth.OnValueChanged += OnHealthValueChanged;
            InitializeHealthBar();
            UpdateHealthUI();
        }

        [ServerRpc]
        private void InitializeHealthServerRpc(int health)
        {
            if (_currentHealth.Value == 0)
                _currentHealth.Value = health;
        }

        public override void OnNetworkDespawn()
        {
            _currentHealth.OnValueChanged -= OnHealthValueChanged;
            base.OnNetworkDespawn();
        }

        protected virtual void InitializeHealthBar()
        {
        }

        protected virtual void UpdateHealthUI()
        {
        }

        public virtual void TakeDamage(int damage, ulong attackerId)
        {
            if (!IsOwner)
            {
                TakeDamageServerRpc(damage, attackerId);
                return;
            }

            TakeDamageServerRpc(damage, attackerId);
        }

        [ServerRpc]
        private void TakeDamageServerRpc(int damage, ulong attackerId)
        {
            if (_currentHealth.Value <= 0)
                return;

            int actualDamage = Mathf.Min(damage, _currentHealth.Value);
            _currentHealth.Value -= actualDamage;

            Debug.Log($"<color=red>[{GetType().Name}] {gameObject.name} received {actualDamage} damage. Health: {_currentHealth.Value}/{maxHealth}</color>");

            ShowDamageEffectClientRpc();

            if (_currentHealth.Value <= 0)
            {
                Die(attackerId);
            }
        }

        protected virtual void Die(ulong killerId)
        {
            Debug.Log($"<color=red>[{GetType().Name}] {gameObject.name} destroyed! Killer: {killerId}</color>");
            OnDestroyed?.Invoke();
            ShowDeathEffectClientRpc();
        }

        [ClientRpc]
        protected void ShowDamageEffectClientRpc()
        {
            if (damageEffectPrefab != null)
            {
                Transform spawnPoint = effectSpawnPoint != null ? effectSpawnPoint : transform;
                GameObject effect = Instantiate(damageEffectPrefab, spawnPoint.position + Vector3.up, Quaternion.identity);
                Destroy(effect, 2f);
            }
        }

        [ClientRpc]
        protected void ShowDeathEffectClientRpc()
        {
            if (destroyEffectPrefab != null)
            {
                Transform spawnPoint = effectSpawnPoint != null ? effectSpawnPoint : transform;
                GameObject effect = Instantiate(destroyEffectPrefab, spawnPoint.position, Quaternion.identity);
                Destroy(effect, 3f);
            }
        }

        protected virtual void OnHealthValueChanged(int previousValue, int newValue)
        {
            OnHealthChanged?.Invoke(newValue, maxHealth);
            UpdateHealthUI();
        }

        public int GetCurrentHealth() => _currentHealth.Value;
        public int GetMaxHealth() => maxHealth;
        public float GetHealthPercentage() => maxHealth > 0 ? (float)_currentHealth.Value / maxHealth : 0f;
        public bool IsDead() => _currentHealth.Value <= 0;

        public virtual void Heal(int amount)
        {
            if (!IsOwner)
            {
                HealServerRpc(amount);
                return;
            }

            HealServerRpc(amount);
        }

        [ServerRpc]
        private void HealServerRpc(int amount)
        {
            int healAmount = Mathf.Min(amount, maxHealth - _currentHealth.Value);
            _currentHealth.Value += healAmount;

            Debug.Log($"<color=green>[{GetType().Name}] {gameObject.name} healed {healAmount}. Health: {_currentHealth.Value}/{maxHealth}</color>");
        }
    }
}