draft options working; spells won't cast though

Assets/_Project/Scripts/Gameplay/BuilderSpells/BuilderSpellDefinition.cs

@@ -0,0 +1,91 @@
+// Assets/_Project/Scripts/Gameplay/BuilderSpells/BuilderSpellDefinition.cs
+using UnityEngine;
+using TD.Core;
+
+namespace TD.Gameplay.BuilderSpells
+{
+    /// <summary>
+    /// Base class for one builder spell — a player-cast, key-triggered ability (e.g. "drop a
+    /// fireball on a point", "slow enemies in a radius"). Granted via the draft (<see
+    /// cref="TD.Gameplay.Draft.BuilderSpellDraftOption"/>) and tracked per-player by <see
+    /// cref="PlayerSpellLoadout"/>, which owns the hotkey slot and cooldown state.
+    /// </summary>
+    /// <remarks>
+    /// <para><b>Contrast with <see cref="BuilderEffects.BuilderEffectDefinition"/>.</b> Effects
+    /// are passive and queried by consumers; spells are active and resolve themselves.
+    /// <see cref="ServerCast"/> is that resolution — it IS the "apply the effect" method,
+    /// replacing the effect system's <c>IsValidFor</c>-only gate pattern (grant-time validity
+    /// still lives on <see cref="TD.Gameplay.Draft.BuilderSpellDraftOption.IsValidFor"/>).</para>
+    ///
+    /// <para><b>One asset per kind.</b> <see cref="Kind"/> is fixed per subclass, same as
+    /// <see cref="BuilderEffects.BuilderEffectDefinition"/>. <see cref="BuilderSpellPool"/> uses
+    /// it to build a fixed-size, enum-indexed lookup table.</para>
+    ///
+    /// <para><b>Server-only resolution, client-only visual.</b> <see cref="ServerCast"/> runs on
+    /// the server and applies damage/status via the same <c>Physics.OverlapSphereNonAlloc</c> +
+    /// <c>EnemyHealth</c>/<c>EnemyStatus</c> pattern <c>TowerCombat</c> already uses.
+    /// <see cref="ClientPlayVfx"/> runs on every peer (including the server) after a successful
+    /// cast, purely for presentation.</para>
+    /// </remarks>
+    public abstract class BuilderSpellDefinition : ScriptableObject
+    {
+        /// <summary>Which builder spell this asset's data belongs to.</summary>
+        public abstract BuilderSpellKind Kind { get; }
+
+        [Header("Presentation")]
+        [Tooltip("Name shown on the draft card and the cast hotbar.")]
+        public string DisplayName;
+
+        [Tooltip("Short description shown on the draft card.")]
+        [TextArea(2, 4)]
+        public string Description;
+
+        [Tooltip("Icon shown on the draft card and the cast hotbar.")]
+        public Sprite Icon;
+
+        [Header("Casting")]
+        [Tooltip("Seconds before this spell can be cast again after a successful cast.")]
+        [Min(0f)]
+        public float Cooldown = 5f;
+
+        [Tooltip("How the cast controller aims this spell. AreaOfEffect previews Radius as a " +
+                 "decal while aiming; PointTarget does not, even if Radius is used internally " +
+                 "(e.g. a splash radius).")]
+        public SpellTargetType TargetType;
+
+        [Tooltip("AreaOfEffect: the resolution radius AND the client-side preview size. " +
+                 "PointTarget: optional internal-only radius (e.g. splash) with no preview.")]
+        [Min(0f)]
+        public float Radius;
+
+        [Tooltip("Physics layer(s) enemies occupy, queried by this spell's own OverlapSphere " +
+                 "call. Each spell asset authors its own mask — same convention as " +
+                 "TowerCombat/Projectile's per-instance enemyLayerMask.")]
+        [SerializeField]
+        protected LayerMask enemyLayerMask;
+
+        // Shared scratch buffer for OverlapSphereNonAlloc queries. The server processes casts
+        // sequentially (one RPC handler at a time), so a static buffer shared across all spell
+        // assets is safe — mirrors TowerCombat.s_overlapBuffer, but sized larger (64 vs. 32):
+        // OverlapSphereNonAlloc silently truncates past the buffer length with no way to
+        // detect the truncation, and spells are more likely than a single tower's splash/chain
+        // radius to catch a dense horde. TowerCombat's buffer is intentionally left at 32 —
+        // out of scope here, flagged separately for the team to revisit.
+        protected static readonly Collider[] s_overlapBuffer = new Collider[64];
+
+        /// <summary>
+        /// Server-only: resolve this spell's effect at <paramref name="targetPoint"/> for the
+        /// casting player. Returns false if the cast could not be applied (e.g. hit nothing) —
+        /// <see cref="PlayerSpellLoadout"/> treats a false return as a no-op and does not start
+        /// the cooldown.
+        /// </summary>
+        public abstract bool ServerCast(ulong clientId, Vector3 targetPoint);
+
+        /// <summary>
+        /// Runs on every peer (via <see cref="PlayerSpellLoadout"/>'s ClientRpc) after a
+        /// successful <see cref="ServerCast"/>. Default no-op; override to spawn an impact VFX
+        /// prefab and self-destroy it, the same idiom used elsewhere for one-off visuals.
+        /// </summary>
+        public virtual void ClientPlayVfx(Vector3 targetPoint) { }
+    }
+}