Initial commit

game/combat.ts

@@ -0,0 +1,70 @@
+/** Counts refer to tokens, while dial values refer to battle strength. */
+export type CombatForces = {
+  normal: number;
+  normalFixedHalf?: boolean;
+  elite: number;
+  eliteStrength: 1 | 2;
+  freeSupport: boolean;
+};
+export type Casualties = {
+  normal: number;
+  elite: number;
+  paidNormal: number;
+  paidElite: number;
+};
+
+/** Every loss combination consistent with the revealed dial and spice payment. */
+export function casualtyOptions(
+  forces: CombatForces,
+  dial: number,
+  support: number,
+): Casualties[] {
+  if (
+    !Number.isFinite(dial) ||
+    dial < 0 ||
+    !Number.isInteger(dial * 2) ||
+    !Number.isInteger(support) ||
+    support < 0 ||
+    (forces.freeSupport && support !== 0)
+  )
+    return [];
+  const options: Casualties[] = [];
+  for (let elite = 0; elite <= forces.elite; elite++) {
+    for (let normal = 0; normal <= forces.normal; normal++) {
+      if (forces.freeSupport) {
+        if (
+          normal * (forces.normalFixedHalf ? 0.5 : 1) +
+            elite * forces.eliteStrength ===
+          dial
+        )
+          options.push({ normal, elite, paidNormal: 0, paidElite: 0 });
+        continue;
+      }
+      for (
+        let paidElite = Math.max(0, support - normal);
+        paidElite <= Math.min(elite, support);
+        paidElite++
+      ) {
+        const paidNormal = support - paidElite;
+        if (forces.normalFixedHalf && paidNormal !== 0) continue;
+        const doubledStrength =
+          normal + paidNormal + (elite + paidElite) * forces.eliteStrength;
+        if (doubledStrength === dial * 2) {
+          options.push({ normal, elite, paidNormal, paidElite });
+          break; // Different support allocations with identical token losses are equivalent choices.
+        }
+      }
+    }
+  }
+  return options;
+}
+
+export function specialForceName(faction: string) {
+  return faction === 'emperor'
+    ? 'Sardaukar'
+    : faction === 'fremen'
+      ? 'Fedaykin'
+      : faction === 'ixians'
+        ? 'Cyborg'
+        : 'Elite';
+}