import { SIZE } from "./mapUtils.js";

export function changedCellsSince(before, after, prefectureMask, sea) {
  let changed = 0;
  for (let i = 0; i < SIZE; i++) if (prefectureMask[i] && !sea[i] && before[i] !== after[i]) changed++;
  return changed;
}

export function municipalityAreaById(adminId, prefectureMask, sea) {
  const area = new Map();
  for (let i = 0; i < SIZE; i++) {
    if (!prefectureMask[i] || sea[i] || adminId[i] < 0) continue;
    area.set(adminId[i], (area.get(adminId[i]) || 0) + 1);
  }
  return area;
}

export function maskLandArea(mask, sea) {
  let area = 0;
  for (let i = 0; i < SIZE; i++) if (mask[i] && !sea[i]) area++;
  return area;
}


export function isProtectedAdminSeed(seed) {
  if (!seed) return false;
  if (seed.seedKind === "capital" || seed.protectedCity?.isPrefecturalCapital) return true;
  if (seed.seedKind === "modernCity" && (seed.protectedCity?.population || seed.population || 0) >= 180000) return true;
  if (seed.seedKind === "port" && seed.portClass === "major") return true;
  if (seed.seedKind === "satelliteCity" && (seed.protectedSatellite?.population || seed.population || 0) >= 60000) return true;
  return false;
}

export function buildSeedLifecycle(adminCenters, adminId, prefectureMask, sea, minArea = 80) {
  const areaById = municipalityAreaById(adminId, prefectureMask, sea);
  const lifecycle = adminCenters.map((center, id) => {
    const protectedSeed = isProtectedAdminSeed(center);
    const area = areaById.get(id) || 0;
    const enoughArea = area >= (protectedSeed ? 28 : minArea);
    return {
      id,
      protected: protectedSeed,
      area,
      state: enoughArea || protectedSeed ? "survived" : "pending",
    };
  });
  return lifecycle;
}

export function activeSeedIds(seedLifecycle) {
  return new Set(seedLifecycle.filter((seed) => seed.state === "survived" || seed.protected).map((seed) => seed.id));
}

export function dominantCompartmentOwners(compartments, adminId) {
  const owner = new Int16Array(compartments.length);
  owner.fill(-1);
  for (const unit of compartments) {
    if (!unit || unit.area === 0) continue;
    const counts = new Map();
    for (const i of unit.cells) {
      const id = adminId[i];
      if (id >= 0) counts.set(id, (counts.get(id) || 0) + 1);
    }
    let bestId = -1, best = -1;
    for (const [id, count] of counts) if (count > best) { best = count; bestId = id; }
    owner[unit.id] = bestId;
  }
  return owner;
}

export function applyCompartmentOwners(adminId, compartments, owner) {
  for (const unit of compartments) {
    if (!unit || unit.area === 0) continue;
    const id = owner[unit.id];
    if (id < 0) continue;
    for (const i of unit.cells) adminId[i] = id;
  }
}