Fix max damage calculations when you mix exploding with conditional b…

…onus (#53)

## Fixes

- Fix max damage calculations when you mix exploding modifier with conditional bonus modifier (that applies on the same characteristic)
    - It was incorrectly applying the conditional bonus to the exploded values

api/constants.ts

@@ -15,4 +15,10 @@ export const getCharacteristic = (val: string): Characteristic | null => {
   return null;
 };
 
+export const getCharacteristicsAfter = (characteristic: Characteristic): Characteristic[] => {
+  const values = Object.keys(Characteristic).map((key) => Characteristic[key]);
+  const index = values.indexOf(characteristic);
+  return values.slice(index + 1);
+};
+
 export const SAVES = [2, 3, 4, 5, 6, 0];

api/processors/maxDamageProcessor.ts

@@ -1,4 +1,4 @@
-import { Characteristic as C } from '../constants';
+import { Characteristic as C, getCharacteristicsAfter } from '../constants';
 import { MODIFIERS as m } from '../models/modifiers';
 import type WeaponProfile from '../models/weaponProfile';
 
@@ -31,9 +31,22 @@ export default class MaxDamageProcessor {
 
   private getMaxDamageForModel(): number {
     const { attacks, damage } = this.profile;
-    const attacksMax = this.resolveExplodingModifiers(attacks.max + this.resolveBonusModifiers(C.ATTACKS));
-    const damageMax = this.resolveMortalWounds(damage.max + this.resolveBonusModifiers(C.DAMAGE));
-    return attacksMax * damageMax;
+    const baseAttacks = attacks.max + this.resolveBonusModifiers(C.ATTACKS);
+
+    const baseDamage = this.resolveMortalWounds(damage.max + this.resolveBonusModifiers(C.DAMAGE));
+    const fullConditionalDamage = baseDamage + this.getConditionalBonusDamage(null, C.DAMAGE);
+
+    const baseAttacksDamage = baseAttacks * fullConditionalDamage;
+
+    return m.EXPLODING.availableCharacteristics.reduce((acc, c) => {
+      const mod = this.profile.modifiers.getModifier(m.EXPLODING, c);
+      if (mod && mod.extraHits.max > 0) {
+        const extraHits = baseAttacks * mod.extraHits.max;
+        const conditionalDamage = baseDamage + this.getConditionalBonusDamage(c, C.DAMAGE);
+        return acc + extraHits * conditionalDamage;
+      }
+      return acc;
+    }, baseAttacksDamage);
   }
 
   private resolveBonusModifiers(characteristic: C): number {
@@ -42,25 +55,26 @@ export default class MaxDamageProcessor {
     if (modList && modList.length) {
       bonus += modList.reduce((acc, mod) => acc + mod.bonus.max, 0);
     }
+    return bonus;
+  }
 
-    m.CONDITIONAL_BONUS.availableCharacteristics.forEach((c) => {
+  private getConditionalBonusDamage(fromCharacteristic: C | null, forCharacteristic: C): number {
+    let bonus = 0;
+    let { availableCharacteristics } = m.CONDITIONAL_BONUS;
+    if (fromCharacteristic !== null) {
+      availableCharacteristics = availableCharacteristics.filter((val) =>
+        getCharacteristicsAfter(fromCharacteristic).includes(val),
+      );
+    }
+    availableCharacteristics.forEach((c) => {
       const mod = this.profile.modifiers.getModifier(m.CONDITIONAL_BONUS, c);
-      if (mod && mod.bonusToCharacteristic === characteristic) {
+      if (mod && mod.bonusToCharacteristic === forCharacteristic) {
         bonus += mod.bonus.max;
       }
     });
-
     return bonus;
   }
 
-  private resolveExplodingModifiers(numAttacks: number): number {
-    return m.EXPLODING.availableCharacteristics.reduce((acc, c) => {
-      const mod = this.profile.modifiers.getModifier(m.EXPLODING, c);
-      if (mod && mod.extraHits.max > 0) return acc + numAttacks * mod.extraHits.max;
-      return acc;
-    }, numAttacks);
-  }
-
   private resolveMortalWounds(currentMax: number): number {
     let cumulativeMax = currentMax;
     let discreteMax = 0;

api/tests/maxDamageProcessor.test.ts

@@ -52,4 +52,9 @@ describe('MaxDamageProcessor', () => {
   test('Rattling Gunners', () => {
     expect(u.rattlingGunners.maxDamage()).toEqual(12);
   });
+
+  test('Edge Cases', () => {
+    expect(u.explodingAndConditionalSame.maxDamage()).toEqual(21);
+    expect(u.explodingAndConditionalDifferent.maxDamage()).toEqual(27);
+  });
 });

api/tests/utils/units.ts

@@ -130,3 +130,42 @@ export const plagueMonksOld = new Unit('Plague Monks (pre Dec 2019 FAQ)', [
 export const rattlingGunners = new Unit('Rattling Gunners', [
   new WeaponProfile(1, DiceValue.parse('2D6'), 4, 4, 1, 1, []),
 ]);
+
+// #region edge cases
+export const explodingAndConditionalSame = new Unit('Exploding And Conditional (Same Characteristic)', [
+  new WeaponProfile(1, 3, 3, 4, 1, 2, [
+    new m.EXPLODING({
+      characteristic: C.TO_HIT,
+      on: 6,
+      extraHits: 2,
+      unmodified: true,
+    }),
+    new m.CONDITIONAL_BONUS({
+      characteristic: C.TO_HIT,
+      bonus: 1,
+      unmodified: true,
+      bonusToCharacteristic: C.DAMAGE,
+    }),
+  ]),
+]);
+
+export const explodingAndConditionalDifferent = new Unit(
+  'Exploding And Conditional (Different Characteristic)',
+  [
+    new WeaponProfile(1, 3, 3, 4, 1, 2, [
+      new m.EXPLODING({
+        characteristic: C.TO_HIT,
+        on: 6,
+        extraHits: 2,
+        unmodified: true,
+      }),
+      new m.CONDITIONAL_BONUS({
+        characteristic: C.TO_WOUND,
+        bonus: 1,
+        unmodified: true,
+        bonusToCharacteristic: C.DAMAGE,
+      }),
+    ]),
+  ],
+);
+// #endregion

client/package.json

@@ -1,6 +1,6 @@
 {
     "name": "statshammer",
-    "version": "2.1.0",
+    "version": "2.1.1",
     "private": true,
     "proxy": "http://localhost:5000/",
     "dependencies": {

lerna.json

@@ -3,6 +3,6 @@
         "*",
         "."
     ],
-    "version": "2.1.0",
+    "version": "2.1.1",
     "npmClient": "yarn"
 }

package.json

@@ -1,7 +1,7 @@
 {
     "name": "statshammer-express",
     "private": true,
-    "version": "2.1.0",
+    "version": "2.1.1",
     "engines": {
         "node": "12.16.3",
         "yarn": "1.22.4"