From 0d93574e767eed7b3df250a1bfb84a6e5f98d2a7 Mon Sep 17 00:00:00 2001
From: root <root@dflike.hookstrapmx>
Date: Tue, 10 Mar 2026 02:17:50 +0000
Subject: [PATCH] feat: add RuntimeConstants service with get/update/reset

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---
 .../config/__tests__/runtimeConstants.test.ts | 42 +++++++++++++++
 server/src/config/runtimeConstants.ts         | 52 +++++++++++++++++++
 2 files changed, 94 insertions(+)
 create mode 100644 server/src/config/__tests__/runtimeConstants.test.ts
 create mode 100644 server/src/config/runtimeConstants.ts

diff --git a/server/src/config/__tests__/runtimeConstants.test.ts b/server/src/config/__tests__/runtimeConstants.test.ts
new file mode 100644
index 0000000..805e79f
--- /dev/null
+++ b/server/src/config/__tests__/runtimeConstants.test.ts
@@ -0,0 +1,42 @@
+import { describe, it, expect, beforeEach } from 'vitest';
+import { createRuntimeConstants } from '../runtimeConstants.js';
+
+describe('RuntimeConstants', () => {
+  let rc: ReturnType<typeof createRuntimeConstants>;
+
+  beforeEach(() => {
+    rc = createRuntimeConstants();
+  });
+
+  it('initializes with default values from shared constants', () => {
+    const constants = rc.getAll();
+    expect(constants.TICK_RATE).toBe(10);
+    expect(constants.HUNGER_DECAY_PER_TICK).toBe(0.05);
+    expect(constants.AWARENESS_RADIUS).toBe(5);
+  });
+
+  it('updates a single constant', () => {
+    rc.update('TICK_RATE', 20);
+    expect(rc.getAll().TICK_RATE).toBe(20);
+  });
+
+  it('rejects unknown keys gracefully', () => {
+    const result = rc.update('NOT_A_KEY' as any, 5);
+    expect(result).toBe(false);
+  });
+
+  it('resets all to defaults', () => {
+    rc.update('TICK_RATE', 20);
+    rc.update('HUNGER_DECAY_PER_TICK', 1.0);
+    rc.resetDefaults();
+    const constants = rc.getAll();
+    expect(constants.TICK_RATE).toBe(10);
+    expect(constants.HUNGER_DECAY_PER_TICK).toBe(0.05);
+  });
+
+  it('get() returns individual constant value', () => {
+    expect(rc.get('MOVE_SPEED')).toBe(0.75);
+    rc.update('MOVE_SPEED', 1.5);
+    expect(rc.get('MOVE_SPEED')).toBe(1.5);
+  });
+});
diff --git a/server/src/config/runtimeConstants.ts b/server/src/config/runtimeConstants.ts
new file mode 100644
index 0000000..6d627ef
--- /dev/null
+++ b/server/src/config/runtimeConstants.ts
@@ -0,0 +1,52 @@
+import type { TunableConstants, TunableKey } from '@dflike/shared';
+import {
+  TICK_RATE, BROADCAST_EVERY_N_TICKS,
+  HUNGER_DECAY_PER_TICK, ENERGY_DECAY_PER_TICK, HUNGER_THRESHOLD, ENERGY_THRESHOLD, NEED_RECOVERY_RATE,
+  SLEEP_ENERGY_RECOVERY_PER_TICK, SLEEP_HUNGER_DECAY_MULTIPLIER, SLEEP_WAKE_THRESHOLD, SLEEP_VOLUNTARY_ENERGY_THRESHOLD,
+  PRODUCTIVITY_DECAY_PER_TICK, PRODUCTIVITY_THRESHOLD, PRODUCTIVITY_RECOVERY_RATE,
+  DAY_NIGHT_RATIO, DAY_HOURS, SUNSET_DURATION_HOURS, SUNRISE_DURATION_HOURS, NIGHT_DARKNESS,
+  AWARENESS_RADIUS, FACING_DURATION, PAUSING_DURATION, EMOTING_DURATION,
+  SOCIAL_GLOBAL_COOLDOWN, SOCIAL_PAIR_COOLDOWN, PROPOSAL_EMOTING_DURATION,
+  MAX_NPC_COUNT, MOVE_SPEED,
+} from '@dflike/shared';
+
+const DEFAULTS: TunableConstants = {
+  TICK_RATE, BROADCAST_EVERY_N_TICKS,
+  HUNGER_DECAY_PER_TICK, ENERGY_DECAY_PER_TICK, HUNGER_THRESHOLD, ENERGY_THRESHOLD, NEED_RECOVERY_RATE,
+  SLEEP_ENERGY_RECOVERY_PER_TICK, SLEEP_HUNGER_DECAY_MULTIPLIER, SLEEP_WAKE_THRESHOLD, SLEEP_VOLUNTARY_ENERGY_THRESHOLD,
+  PRODUCTIVITY_DECAY_PER_TICK, PRODUCTIVITY_THRESHOLD, PRODUCTIVITY_RECOVERY_RATE,
+  DAY_NIGHT_RATIO, DAY_HOURS, SUNSET_DURATION_HOURS, SUNRISE_DURATION_HOURS, NIGHT_DARKNESS,
+  AWARENESS_RADIUS, FACING_DURATION, PAUSING_DURATION, EMOTING_DURATION,
+  SOCIAL_GLOBAL_COOLDOWN, SOCIAL_PAIR_COOLDOWN, PROPOSAL_EMOTING_DURATION,
+  MAX_NPC_COUNT, MOVE_SPEED,
+};
+
+export function createRuntimeConstants() {
+  const current: TunableConstants = { ...DEFAULTS };
+
+  return {
+    get<K extends TunableKey>(key: K): TunableConstants[K] {
+      return current[key];
+    },
+
+    getAll(): TunableConstants {
+      return { ...current };
+    },
+
+    update(key: TunableKey, value: number): boolean {
+      if (!(key in DEFAULTS)) return false;
+      current[key] = value;
+      return true;
+    },
+
+    resetDefaults(): void {
+      Object.assign(current, DEFAULTS);
+    },
+
+    getDefaults(): TunableConstants {
+      return { ...DEFAULTS };
+    },
+  };
+}
+
+export type RuntimeConstants = ReturnType<typeof createRuntimeConstants>;