Clamp generated package expiry to travel time at max catalog speed + buffer so long jobs are finishable (ISS-119)

lib/game/seed.ts

@@ -1,6 +1,7 @@
 import { haversineKm } from '@/lib/geo';
+import { travelDurationMs } from '@/lib/sim/movement';
 import { WORLD_TIME_SCALE } from '@/lib/worldClock';
-import { PLANE_TYPES, repRate, STARTER_MODEL } from './catalog';
+import { FASTEST_CATALOG_SPEED_KMH, PLANE_TYPES, repRate, STARTER_MODEL } from './catalog';
 import { pickSpecial, SPECIALS } from './specials';
 
 // First-run seed. Everything here is a pure function of (airports, rng, nowMs)
@@ -123,6 +124,10 @@ const LEG_CAP_MAX_ATTEMPTS = 25;
 const DEADLINE_MIN_HOURS = 6;
 const DEADLINE_MAX_HOURS = 72;
 
+// v0.54.0 (ISS-119): flat slack added to travel time in the expiry floor — a deadline must leave at
+// least this much after the fastest plane lands, so dispatch + landing are never instant.
+export const EXPIRY_BUFFER_MS = 3_600_000; // 1 h
+
 const CARGO_TYPES = ['Passengers', 'Mail', 'Perishables', 'Electronics', 'Auto parts'] as const;
 
 // ponytail: balance-tunable unit weights (kg per passenger/pallet). Chosen so every cargo
@@ -157,6 +162,9 @@ export function rewardFor(km: number, weightKg: number): number {
 // v0.38.0 (ISS-072): reputation optionally scales the reward (×(1 + repRate)) at the same spot
 // as the special multiplier — a pure input, it consumes NO RNG draws and defaults to the
 // starting value so seed-time behavior is byte-identical.
+// v0.54.0 (ISS-119): the drawn deadline window is clamped UP by an expiry floor (travel time at
+// FASTEST_CATALOG_SPEED_KMH + EXPIRY_BUFFER_MS) after special scaling, so every package is
+// finishable by the fastest catalog plane; short legs are byte-identical to before.
 export function generatePackage(input: {
   id: string;
   airports: SeedAirport[];
@@ -230,8 +238,15 @@ export function generatePackage(input: {
   // forced value (including explicit null) skips it, same pattern as the other overrides.
   const special = input.special !== undefined ? input.special : pickSpecial(rng);
   const mods = special !== null ? SPECIALS[special] : undefined;
-  // Forced deadlines skip the special scaling — consistent with overrides skipping draws.
-  const deadlineMs = input.deadlineOffsetMs ?? drawnWindowMs * (mods?.deadlineScale ?? 1);
+  // v0.54.0 (ISS-119): expiry floor — every package must be finishable by the fastest catalog plane:
+  // deadline ≥ now + travel time at FASTEST_CATALOG_SPEED_KMH + EXPIRY_BUFFER_MS. The drawn window is a
+  // single uniform value, so clamping it up AFTER special scaling covers both requirements: short legs
+  // (drawn × scale already above the floor) are byte-identical to before, and when the raw draw falls
+  // below the floor the deadline lands exactly on it — which stays ≤ the scaled ceiling for any pair of
+  // airports on Earth (max leg ~20000 km → floor ≈ 22.8 h < the 36 h priority ceiling), so no separate
+  // ceiling raise is needed. Forced offsets skip the floor, same as they skip the special scaling.
+  const expiryFloorMs = travelDurationMs(km, FASTEST_CATALOG_SPEED_KMH) + EXPIRY_BUFFER_MS;
+  const deadlineMs = input.deadlineOffsetMs ?? Math.max(drawnWindowMs * (mods?.deadlineScale ?? 1), expiryFloorMs);
 
   // v0.38.0 (ISS-072): reputation bonus composed with the special multiplier, single round at the end.
   const repBonus = 1 + repRate(input.reputation ?? STARTING_REPUTATION, JOB_BONUS_PER_REP, MAX_JOB_BONUS);