megakoop/Game/Scripts/Combat/Health.cs

using System;
using UnityEngine;
using UnityEngine.Events;

namespace MegaKoop.Game.Combat
{
    [DisallowMultipleComponent]
    public class Health : MonoBehaviour, IDamageable
    {
        [SerializeField] private float maxHealth = 100f;
        [SerializeField] private Team team = Team.Neutral;
        [SerializeField] private bool ignoreFriendlyFire = true;
        [SerializeField] private bool destroyOnDeath = false;
        [SerializeField] private UnityEvent<float> onHealthChanged;
        [SerializeField] private UnityEvent onDeath;

        public float MaxHealth => maxHealth;
        public float CurrentHealth { get; private set; }
        public Team Team => team;
        public bool IsAlive => CurrentHealth > 0f;

        public event Action<float> NormalizedHealthChanged;

        private void Awake()
        {
            maxHealth = Mathf.Max(1f, maxHealth);
            CurrentHealth = maxHealth;
            onHealthChanged?.Invoke(CurrentHealth / MaxHealth);
            NormalizedHealthChanged?.Invoke(CurrentHealth / MaxHealth);
        }

        public void ApplyDamage(DamagePayload payload)
        {
            if (!IsAlive || payload.Amount <= 0f)
            {
                return;
            }

            if (ignoreFriendlyFire && team != Team.Neutral && payload.SourceTeam == team)
            {
                return;
            }

            CurrentHealth = Mathf.Max(0f, CurrentHealth - payload.Amount);
            float normalized = CurrentHealth / MaxHealth;
            onHealthChanged?.Invoke(normalized);
            NormalizedHealthChanged?.Invoke(normalized);

            if (CurrentHealth <= 0f)
            {
                HandleDeath();
            }
        }

        public void Heal(float amount)
        {
            if (amount <= 0f || !IsAlive)
            {
                return;
            }

            CurrentHealth = Mathf.Min(MaxHealth, CurrentHealth + amount);
            float normalized = CurrentHealth / MaxHealth;
            onHealthChanged?.Invoke(normalized);
            NormalizedHealthChanged?.Invoke(normalized);
        }

        public void Revive(float overrideMaxHealth = -1f)
        {
            if (overrideMaxHealth > 0f)
            {
                maxHealth = Mathf.Max(1f, overrideMaxHealth);
            }

            CurrentHealth = maxHealth;
            float normalized = CurrentHealth / MaxHealth;
            onHealthChanged?.Invoke(normalized);
            NormalizedHealthChanged?.Invoke(normalized);
        }

        private void HandleDeath()
        {
            onDeath?.Invoke();

            if (destroyOnDeath)
            {
                Destroy(gameObject);
            }
        }

        private void OnValidate()
        {
            maxHealth = Mathf.Max(1f, maxHealth);
        }

        public void ForceSetNormalizedHealth(float normalized)
        {
            normalized = Mathf.Clamp01(normalized);
            bool wasAlive = IsAlive;
            CurrentHealth = normalized * MaxHealth;
            onHealthChanged?.Invoke(normalized);
            NormalizedHealthChanged?.Invoke(normalized);

            if (CurrentHealth <= 0f && wasAlive)
            {
                HandleDeath();
            }
        }
    }
}