// Assets/_Project/Scripts/Gameplay/EnemyAbilities/FlightAbilityDefinition.cs
using UnityEngine;
using TD.Core;

namespace TD.Gameplay.EnemyAbilities
{
    /// <summary>
    /// Grounded enemies take to the air: they path over the baked terrain grid instead of through
    /// the maze, and towers flagged ground-only can no longer touch them.
    /// </summary>
    /// <remarks>
    /// <b>The single most punishing card in the set</b>, because it doesn't weaken the maze — it
    /// deletes it. Everything a player built to lengthen the route stops mattering for that wave,
    /// and only their anti-air coverage counts. Weight it accordingly in the pools.
    ///
    /// <para>Purely a spawn-time change: <c>EnemyMovement</c> reads the flying flag once at
    /// initialization to pick which grid to path on and to opt out of re-path scheduling, and
    /// <c>TowerCombat</c> reads the replicated flag on <c>EnemyHealth</c> when filtering targets.
    /// Both are already wired for flight — this card only has to flip the bit before the enemy is
    /// built.</para>
    /// </remarks>
    [CreateAssetMenu(fileName = "FlightAbility", menuName = "TD/Enemy Abilities/Flight")]
    public class FlightAbilityDefinition : EnemyAbilityDefinition
    {
        public override EnemyAbilityKind Kind => EnemyAbilityKind.Flight;

        [Header("Flight")]
        [Tooltip("Height above the ground these enemies hover at. Keep modest — tower targeting " +
                 "uses 3D range, so altitude eats into the effective reach of anything that CAN " +
                 "shoot them.")]
        [Min(0f)]
        public float FlightHeight = 3f;

        [Tooltip("Speed multiplier applied when the enemy takes flight. Flying enemies travel a " +
                 "much shorter route, so values below 1 are a reasonable counterweight.")]
        [Range(0.1f, 2f)]
        public float SpeedMultiplier = 1f;

        public override void ServerModifySpawn(ref EnemySpawnContext context)
        {
            // Already-flying enemies keep their authored height rather than being overwritten by
            // this card's — the wave was designed around it, and stacking Flight onto a flier
            // shouldn't quietly relocate it.
            if (!context.IsFlying)
            {
                context.IsFlying     = true;
                context.FlightHeight = FlightHeight;
            }

            context.MoveSpeed *= SpeedMultiplier;
        }
    }
}