// Assets/_Project/Scripts/Gameplay/EnemyAbilities/EnemySpawnContext.cs
namespace TD.Gameplay.EnemyAbilities
{
    /// <summary>
    /// Mutable per-spawn copy of an enemy's stats, handed to each of its abilities before the
    /// enemy is built so they can alter what it spawns as.
    /// </summary>
    /// <remarks>
    /// <b>Why a context rather than more parameters.</b> Wave buffs like "grounded enemies become
    /// flying" or "enemies spawn at half health" have to land <i>before</i>
    /// <c>EnemyHealth.InitializeServer</c> and before the spawn position is computed (flyers are
    /// raised by their flight height). Threading each new stat through <c>SpawnEnemy</c> as another
    /// argument was already unwieldy at two; this keeps the signature flat and gives abilities one
    /// obvious place to write.
    ///
    /// <para>Seeded from the <see cref="EnemyDefinition"/>, never written back to it — the
    /// definition is a shared asset and a buff that mutated it would leak across waves, matches,
    /// and (in the editor) sessions.</para>
    /// </remarks>
    public struct EnemySpawnContext
    {
        public float MaxHp;
        public float MoveSpeed;
        public bool  IsFlying;
        public float FlightHeight;
        public int   LivesCost;

        /// <summary>Uniform transform scale relative to the prefab's authored scale.</summary>
        public float VisualScale;

        /// <summary>Seeds a context from an enemy definition's authored stats.</summary>
        public static EnemySpawnContext FromDefinition(EnemyDefinition def) => new EnemySpawnContext
        {
            MaxHp        = def.MaxHp,
            MoveSpeed    = def.MoveSpeed,
            IsFlying     = def.IsFlying,
            FlightHeight = def.FlightHeight,
            LivesCost    = def.LivesCost,
            VisualScale  = 1f,
        };
    }
}