// Assets/_Project/Scripts/Gameplay/EnemyUpgrades/DoubleUpEnemyUpgradeOption.cs
using UnityEngine;
using TD.Gameplay.Waves;

namespace TD.Gameplay.EnemyUpgrades
{
    /// <summary>
    /// Vote-meta card: the next time this wave is cleared, it takes several buffs automatically
    /// and the players get no say in which.
    /// </summary>
    /// <remarks>
    /// <b>Not an enemy ability.</b> Nothing about the enemies changes when this is voted in — it
    /// changes how the <i>next vote</i> on this slot resolves. That's why it derives from
    /// <see cref="EnemyUpgradeOption"/> directly instead of wrapping an
    /// <c>EnemyAbilityDefinition</c>: the spawn path builds ability sets only from ability cards,
    /// so this one is recorded on the slot and otherwise invisible to enemies.
    ///
    /// <para><b>The trade is agency for information.</b> Voting this in is choosing to make one
    /// future wave worse in exchange for it not being the worst option — the auto-draw is weighted
    /// and slot-filtered exactly like a real vote, so it's a gamble on the pool, not a punishment.
    /// It also disarms itself after firing (<c>ServerConsumeAutoApply</c>), so a slot can only be
    /// doubled once per card.</para>
    ///
    /// <para>Repeats are prevented by the normal offer filter: the slot records this card like any
    /// other, so it can't be offered to the same slot twice in a phase.</para>
    /// </remarks>
    [CreateAssetMenu(fileName = "EnemyUpgrade_DoubleUp",
                     menuName = "TD/Enemy Upgrades/Double Up Card", order = 22)]
    public class DoubleUpEnemyUpgradeOption : EnemyUpgradeOption
    {
        [Header("Payload")]
        [Tooltip("How many buffs the wave takes automatically in place of its next vote.")]
        [Min(2)]
        public int BuffsToAutoApply = 2;

        public override bool IsValidForSlot(RunState run, int slot)
        {
            // Pointless to offer while the slot is already armed — the player would be trading a
            // vote away for nothing.
            return run != null && run.GetAutoApplyCount(slot) <= 0;
        }

        public override void ServerOnApplied(RunState run, int slot)
        {
            run?.ServerSetAutoApply(slot, BuffsToAutoApply);
        }
    }
}