refacto: Keeping entrypoints clean and making files by purpose

server/helpers/cell.js

@@ -0,0 +1,55 @@
+import { fnv1a32, hash2u32, mulberry32 } from "../../public/src/rng.js";
+import { generatePlanet, formatPlanet } from "../../public/src/planetGeneration.js";
+
+const GRID_W = 100;
+const GRID_H = 100;
+const OUTER_RADIUS = 50;
+const INNER_RADIUS = 30;
+const PLANET_CHANCE = 0.1;
+
+export function cellCenter(x, y) {
+  const cx = (GRID_W - 1) / 2;
+  const cy = (GRID_H - 1) / 2;
+  return { dx: x - cx, dy: y - cy };
+}
+
+export function isExploitable(x, y) {
+  const { dx, dy } = cellCenter(x, y);
+  const r = Math.hypot(dx, dy);
+  return r <= OUTER_RADIUS - 0.5 && r >= INNER_RADIUS - 0.5;
+}
+
+export function hasPlanetAt(x, y, seedU32) {
+  const h = hash2u32(x, y, seedU32);
+  return h / 4294967296 < PLANET_CHANCE;
+}
+
+export function computeCell(seedStr, x, y) {
+  const seedU32 = fnv1a32(seedStr);
+  const exploitable = isExploitable(x, y);
+  if (!exploitable) {
+    return { x, y, exploitable: false, hasPlanet: false, planet: null, formatted: null };
+  }
+  const hp = hasPlanetAt(x, y, seedU32);
+  if (!hp) {
+    return { x, y, exploitable: true, hasPlanet: false, planet: null, formatted: null };
+  }
+  const h = hash2u32(x, y, seedU32 ^ 0xa5a5a5a5);
+  const rng = mulberry32(h);
+  const planet = generatePlanet(rng);
+  return {
+    x, y, exploitable: true, hasPlanet: true,
+    planet, formatted: formatPlanet(planet),
+  };
+}
+
+export function rowToCellPayload(row) {
+  return {
+    x: row.x,
+    y: row.y,
+    exploitable: row.exploitable,
+    hasPlanet: row.has_planet,
+    planet: row.planet_json ?? null,
+    discoveredBy: row.discovered_by,
+  };
+}