using ProjectM.Simulation;
using Unity.Entities;
using UnityEngine;

namespace ProjectM.Authoring
{
    /// <summary>
    /// Authoring placed once in the gameplay subscene. Bakes a <see cref="ProjectileSpawner"/>
    /// singleton holding the projectile ghost prefab entity, which the predicted AbilityFireSystem
    /// instantiates whenever a player fires. The spawner itself carries no transform (it is a pure
    /// data singleton) so it is baked with <c>TransformUsageFlags.None</c>, while the referenced
    /// prefab is baked with <c>TransformUsageFlags.Dynamic</c> so the spawned projectile has a
    /// runtime-mutable LocalTransform.
    /// </summary>
    public class ProjectileSpawnerAuthoring : MonoBehaviour
    {
        [Tooltip("The projectile ghost prefab spawned when a player fires.")]
        public GameObject ProjectilePrefab;

        private class ProjectileSpawnerBaker : Baker<ProjectileSpawnerAuthoring>
        {
            public override void Bake(ProjectileSpawnerAuthoring authoring)
            {
                // The spawner itself needs no transform; it is a data singleton.
                var entity = GetEntity(authoring, TransformUsageFlags.None);

                AddComponent(entity, new ProjectileSpawner
                {
                    Prefab = GetEntity(authoring.ProjectilePrefab, TransformUsageFlags.Dynamic)
                });
            }
        }
    }
}