Ars 'n Spells

[1.9.0] - 2026-05-10

Bug Fixes (P0 stabilization pass)

• AffinitySyncPacket no longer crashes dedicated servers. Pre-1.9.0, AffinitySyncPacket imported net.minecraft.client.Minecraft directly and was registered unconditionally on the common bus, so the very first cast on a dedicated server attempted to load Minecraft server-side and risked a NoClassDefFoundError. Client logic moved to a new ClientAffinityPacketHandler and the packet now wraps the client-side capability mutation in DistExecutor.unsafeRunWhenOn(Dist.CLIENT, …) — the same pattern ResonanceSyncPacket was already using.
• Iron's Spellbooks is now actually optional. IronsLPHandler was an unconditional @Mod.EventBusSubscriber while importing io.redspace.ironsspellbooks.api.* at the file header — Iron's-less servers crashed at classload. The annotation is removed and the handler is now instance-registered behind the existing ModList.get().isLoaded("irons_spellbooks") block in ArsNSpells. SpellScalingUtil's static initializer (which referenced Iron's AttributeRegistry.*_SPELL_POWER slots) is converted to lazy double-checked init so the map only builds when an Iron's-aware caller actually invokes it. New IronsCompat exposes a cached isLoaded() for the cast hot-path.
• Scroll LP handling is now a real transaction. MixinScrollItem used to consume LP at scroll-use time, ignore the consumption return value, and silently leak the death-on-insufficient-LP path because LPDeathPrevention early-returned when the death-mode config was on. The mixin is rewritten as validate → cast → commit: HEAD calls hasEnoughLP, stages a per-player pending entry via the new ScrollLPTracker helper, and either cancels (safe mode) or lets the scroll proceed (death mode). RETURN reads the original use result and either consumes LP (success), kills the player explicitly (death mode), or no-ops (cast didn't actually consume the action). LP no longer disappears for failed casts, and the death-mode path now does its own enforcement instead of relying on a subsystem that exited early.
• Cooldown "namespacing" was a lie — now removed. UnifiedCooldownManager accepted a String modNamespace argument that suggested per-mod isolation, but the storage was always Map<CooldownCategory, Long> and the namespace only ever appeared in debug logs. The parameter is dropped from every public method, both callers (CooldownHandler and IronsCooldownHandler) updated, and the README "Cooldowns" section now states clearly that the unified system is global per category — an Ars OFFENSIVE cast and an Iron's OFFENSIVE cast intentionally collide. NBT and packet wire formats are unchanged, so existing 1.8.9 saves load cleanly with no migration.

Finished half-wired systems

The pre-1.9.0 README claimed cross-mod progression "and vice versa", "Ars spell potency scales with Iron's spell power attributes", and optional affinity decay. None of those were actually wired. They are now:

• Iron's-side progression hook. New IronsProgressionHandler listens to Iron's SpellOnCastEvent, derives the school from the path component of the school's resource location, and calls into the same ProgressionData.incrementCastCount + <school>_spell_power attribute application that the Ars-side handler uses. The shared logic lives in ProgressionAttributes so both sides use the same modifier UUID and naming.
• Iron's-side affinity hook. New IronsAffinityHandler mirrors AffinityHandler for Iron's casts. The AffinityType enum gains HOLY, ENDER, BLOOD, EVOCATION, ELDRITCH so every Iron's stock school maps onto an entry. Adding enum values is forward and backward compatible — pre-1.9.0 NBT loads cleanly with the new entries defaulting to 0.
• Ars spell scaling actually wired. New ArsSpellScalingHandler computes SpellScalingUtil.getMultiplierForCaster on each Ars SpellCastEvent, stages it for the casting player with a 60-tick window, and applies it on LivingHurtEvent for spell-flavored damage from that player. Final amount is clamped against spell_power_cap. Filter rejects melee/environmental damage so the bonus only flows to actual spell hits.
• Affinity decay tick handler. New AffinityDecayHandler ticks each player every affinity_decay_interval_ticks (default 1200 = 60 s) and prorates the existing affinity_decay_rate from per-day to per-interval (24000 ticks per Minecraft day). Default for enable_affinity_decay is now false for new configs to avoid surprising existing players whose 1.8.9 config had it (no-op-ly) on; existing config files retain their previous setting.
• Login affinity sync. New AffinitySyncOnLoginHandler fires one AffinitySyncPacket per non-zero school when the player joins, so HUD and tooltips reflect persisted state immediately instead of waiting for the next cast. Progression already auto-applies attribute modifiers on login so it doesn't need a packet sweep.
• AffinityCalculator and AffinityBonuses — the per-level damage curve now lives in AffinityCalculator.getDamageBonus and is consumed by AffinityBonuses.getAttributeMultiplier. Same numbers as before; less duplication; no more dead code.

Configuration

• New: affinity_decay_interval_ticks (default 1200, range 20–24000) — how often the new decay handler ticks each player.
• Changed default: enable_affinity_decay is now false for fresh configs (was effectively a no-op true in 1.8.9). Existing configs preserve whatever value the user already had.

Internal

• Mixin-package isolation respected. The transactional scroll-cost state (ScrollLPTracker) lives in the compat package, not as an inner class of MixinScrollItem. Sponge Mixin treats every class inside a mixin package — including a mixin's own inner classes — as off-limits for direct reference, because the mixin class gets merged into its target at load time and stops existing as a standalone class. The first 1.9.0 build paid for that rule with an IllegalClassLoadError on MixinScrollItem$PendingScrollLP; extracting the holder fixed it without behavior change. Worth remembering for any future mixin that needs shared state.

Known follow-ups (deferred to 1.9.1+)

• Aura HUD does not auto-update server-side regen — still updates only on next spell cast or login. Aura sync is queued for 1.10.0.
• SERVER / CLIENT config split. All keys remain on the single COMMON config in 1.9.0.
• Datapack registries for spell schools, cooldown categories, progression rules, cross-cast rules.
• Cross-cast NBT re-validation at cast time (server-trust hardening).
• Capability sync on dimension change / respawn (only login is in scope this round).

Backward compatibility

Strict. AffinityData, ProgressionData, CooldownData, AuraCapability NBT shapes unchanged. Network protocol stays at "1". Inscribed cross-cast items unaffected. No removed config keys, no renamed config keys.