/**
 * MotherShip 登录态官网硬约束（与 dashboard Create shipment 对齐）
 *
 * - 单件平均重量（Weight each）> 5000 lb → 官网不再提供报价
 * - 整票总重 > 53 英尺干货厢式挂车最大载重（45000 lb）→ 不可询价
 * - 不以托盘数量 1–25 为硬拒（各路径均取消该上限）
 */
export const MOTHERSHIP_MAX_AVG_WEIGHT_EACH_LB = 5000;

/** 53 英尺干货厢式挂车最大载重（lb） */
export const MOTHERSHIP_MAX_TOTAL_WEIGHT_LB = 45_000;

/** @deprecated 使用 MOTHERSHIP_MAX_AVG_WEIGHT_EACH_LB */
export const MOTHERSHIP_MAX_WEIGHT_EACH_LB = MOTHERSHIP_MAX_AVG_WEIGHT_EACH_LB;

export const MOTHERSHIP_AVG_WEIGHT_BLOCK_MESSAGE =
  `单件平均重量超过 ${MOTHERSHIP_MAX_AVG_WEIGHT_EACH_LB} 磅时，无法提供报价`;

export const MOTHERSHIP_TOTAL_WEIGHT_BLOCK_MESSAGE =
  `整票总重超过 53 英尺货车最大载重（${MOTHERSHIP_MAX_TOTAL_WEIGHT_LB.toLocaleString("en-US")} 磅），无法提供报价`;

/** 重量/尺寸仅接受整数；有小数须向上取整 */
export const MOTHERSHIP_INTEGER_HINT =
  "重量与尺寸仅支持整数。有小数时系统将自动向上取整（进一）";

/** 一级「货物」标题旁录入限制提示（提前告知，勿等到查价页） */
export const MOTHERSHIP_CARGO_ENTRY_HINT_TITLE =
  "录入提示 (提前告知，勿等到查价页)";

export const MOTHERSHIP_CARGO_ENTRY_HINT_ITEMS = [
  "重量/尺寸支持小数录入 (lb / inch)；点「开始询价」时自动向上取整 (进一) 再提交，例 25.68→26",
  `「单件重」= Weight each，须 ≤ ${MOTHERSHIP_MAX_AVG_WEIGHT_EACH_LB} lb，超出不可询价`,
  `整票总重 = Σ(单件重×数量) 须 ≤ ${MOTHERSHIP_MAX_TOTAL_WEIGHT_LB.toLocaleString("en-US")} lb (53 英尺干货厢式挂车最大载重)，超出不可询价`,
] as const;

/**
 * 官网不接受小数：正数向上取整（ceil）。
 * 例：25.68 → 26，40.1 → 41，25 → 25
 */
export function ceilMothershipNumeric(value: number): number {
  if (!Number.isFinite(value) || value <= 0) return value;
  return Math.ceil(value);
}

export function hasMothershipFractionalPart(value: number): boolean {
  return Number.isFinite(value) && value > 0 && !Number.isInteger(value);
}

/** YYYY-MM-DD → 本地 noon 解析，避免 UTC 偏移改星期 */
export function parseIsoDateLocal(iso: string): Date | null {
  const m = /^(\d{4})-(\d{2})-(\d{2})$/.exec(iso.trim());
  if (!m) return null;
  const d = new Date(Number(m[1]), Number(m[2]) - 1, Number(m[3]), 12, 0, 0);
  return Number.isNaN(d.getTime()) ? null : d;
}

export function toIsoDateLocal(d: Date): string {
  const yyyy = d.getFullYear();
  const mm = String(d.getMonth() + 1).padStart(2, "0");
  const dd = String(d.getDate()).padStart(2, "0");
  return `${yyyy}-${mm}-${dd}`;
}

/** 周六=6 / 周日=0 不可选 */
export function isMothershipWeekendIso(iso: string): boolean {
  const d = parseIsoDateLocal(iso);
  if (!d) return false;
  const day = d.getDay();
  return day === 0 || day === 6;
}

/** 若落在周末，拨到下一工作日（周一） */
export function snapMothershipReadyDateToWeekday(iso: string): string {
  const d = parseIsoDateLocal(iso);
  if (!d) return iso;
  const day = d.getDay();
  if (day === 6) d.setDate(d.getDate() + 2);
  else if (day === 0) d.setDate(d.getDate() + 1);
  return toIsoDateLocal(d);
}

/** 今天 YYYY-MM-DD（本地） */
export function todayIsoDateLocal(): string {
  return toIsoDateLocal(new Date());
}

/** 默认可提货日：今天若为周末则拨到周一 */
export function defaultMothershipReadyDateIso(): string {
  return snapMothershipReadyDateToWeekday(todayIsoDateLocal());
}

/** date input min：与官网一致，不可早于最近工作日 */
export function minMothershipReadyDateIso(): string {
  return defaultMothershipReadyDateIso();
}

/** 所有 MotherShip 日期字段统一规范化 */
export function normalizeMothershipReadyDateIso(
  iso: string | undefined,
): string | undefined {
  const trimmed = iso?.trim();
  if (!trimmed) return undefined;
  return snapMothershipReadyDateToWeekday(trimmed);
}

/**
 * 单件平均重量（lb）。
 * 登录态表单「单件重量 / Weight each」即均重；quantity 仅表示件数，不参与均重计算。
 */
export function resolveMothershipAverageWeightEachLb(
  weightEachLb: number,
  _quantity?: number,
): number {
  return weightEachLb;
}

/** 单件平均重量 ≤ 5000 lb 才允许询价 */
export function isMothershipAverageWeightEachAllowed(
  weightEachLb: number,
): boolean {
  return (
    Number.isFinite(weightEachLb) &&
    weightEachLb > 0 &&
    weightEachLb <= MOTHERSHIP_MAX_AVG_WEIGHT_EACH_LB
  );
}

/** @deprecated 使用 isMothershipAverageWeightEachAllowed */
export function isMothershipWeightEachAllowed(weightEachLb: number): boolean {
  return isMothershipAverageWeightEachAllowed(weightEachLb);
}

export type MothershipCargoWeightLine = {
  weightLb: number;
  quantity?: number;
};

/** 整票总重 = Σ(单件重量 × 数量) */
export function sumMothershipTotalWeightLb(
  lines: MothershipCargoWeightLine[],
): number {
  return lines.reduce((acc, line) => {
    const qty = Math.max(1, Math.round(line.quantity ?? 1));
    const wt = line.weightLb;
    if (!Number.isFinite(wt) || wt <= 0) return acc;
    return acc + wt * qty;
  }, 0);
}

export function isMothershipTotalWeightAllowed(totalLb: number): boolean {
  return (
    Number.isFinite(totalLb) &&
    totalLb > 0 &&
    totalLb <= MOTHERSHIP_MAX_TOTAL_WEIGHT_LB
  );
}

/**
 * 校验多行货物：任一单件平均重量超限则返回阻断文案，否则 null。
 */
export function findMothershipAvgWeightBlockMessage(
  lines: MothershipCargoWeightLine[],
): string | null {
  for (const line of lines) {
    const avg = resolveMothershipAverageWeightEachLb(
      line.weightLb,
      line.quantity,
    );
    if (!isMothershipAverageWeightEachAllowed(avg)) {
      return MOTHERSHIP_AVG_WEIGHT_BLOCK_MESSAGE;
    }
  }
  return null;
}

/** 整票总重超限则返回阻断文案，否则 null */
export function findMothershipTotalWeightBlockMessage(
  lines: MothershipCargoWeightLine[],
): string | null {
  const total = sumMothershipTotalWeightLb(lines);
  if (!isMothershipTotalWeightAllowed(total)) {
    return MOTHERSHIP_TOTAL_WEIGHT_BLOCK_MESSAGE;
  }
  return null;
}

/** 均重或总重任一超限则返回阻断文案 */
export function findMothershipCargoWeightBlockMessage(
  lines: MothershipCargoWeightLine[],
): string | null {
  return (
    findMothershipAvgWeightBlockMessage(lines) ??
    findMothershipTotalWeightBlockMessage(lines)
  );
}