/**
 * Flock 结账选档校验 + 档内灵活性价 / Standard 承运商列表
 */

export type FlockCheckoutTier = "flock_direct" | "standard";

/** 官网 See Pricing Options 后三档（FlockDirect） */
export type FlockFlexibilityKey = "2_day" | "1_day" | "none";

/** 报价形态：灵活价 vs Standard LTL 承运商列表 */
export type FlockPricingOptionsType = "flexibility" | "carriers";

export type FlockCheckoutSelection = {
  preferredTier: FlockCheckoutTier;
  preferredFlexibility?: FlockFlexibilityKey | null;
  /** Standard LTL 承运商名（与 preferredFlexibility 二选一） */
  preferredCarrier?: string | null;
};

export type FlockFlexibilityOption = {
  key: FlockFlexibilityKey;
  /** 行内可见文案（flexibility / pickup / deliver / rate） */
  label: string;
  rateUsd: number;
  pickupWindow?: string;
  deliverBy?: string;
};

/** Standard LTL：See Pricing 后承运商行 */
export type FlockCarrierOption = {
  carrierName: string;
  transitDays: string;
  pickupDate?: string;
  deliveryEstimate?: string;
  rateUsd: number;
  label: string;
};

/** 单档刮取结果（灵活价或承运商） */
export type FlockTierPricingScrape = {
  options_type: FlockPricingOptionsType;
  options: FlockFlexibilityOption[];
  carrier_options: FlockCarrierOption[];
};

export function parseFlockFlexibilityKey(
  label: string,
): FlockFlexibilityKey | null {
  const t = label.replace(/\s+/g, " ").toLowerCase();
  if (/2[-\s]?day\s+flexibility/.test(t)) return "2_day";
  if (/1[-\s]?day\s+flexibility/.test(t)) return "1_day";
  if (/no\s+flexibility/.test(t)) return "none";
  return null;
}

export function flockFlexibilityKeyLabel(key: FlockFlexibilityKey): string {
  switch (key) {
    case "2_day":
      return "2 天灵活性";
    case "1_day":
      return "1 天灵活性";
    case "none":
      return "无灵活性";
    default:
      return key;
  }
}

/** 返回中文错误；null = 通过 */
export function validateFlockCheckoutSelection(
  input: FlockCheckoutSelection,
): string | null {
  const tier = input.preferredTier;
  if (tier !== "flock_direct" && tier !== "standard") {
    return "请选择 FlockDirect® 或 Standard 报价档";
  }
  const carrier = input.preferredCarrier?.trim() || "";
  const hasFlex =
    input.preferredFlexibility === "2_day" ||
    input.preferredFlexibility === "1_day" ||
    input.preferredFlexibility === "none";
  if (carrier && hasFlex) {
    return "灵活性档与承运商不能同时选择";
  }
  if (carrier) {
    if (carrier.length > 128) return "承运商名称过长";
    return null;
  }
  if (!hasFlex) {
    return "请选择灵活性报价档或承运商";
  }
  return null;
}

/** 承运商列表选最低价；同价取首项；空列表返回 -1 */
export function pickLowestCarrierOptionIndex(
  options: FlockCarrierOption[],
): number {
  if (options.length === 0) return -1;
  let best = 0;
  for (let i = 1; i < options.length; i += 1) {
    if (options[i]!.rateUsd < options[best]!.rateUsd) {
      best = i;
    }
  }
  return best;
}

/** 按承运商名选；找不到回落最低价 */
export function pickCarrierOptionIndex(
  options: FlockCarrierOption[],
  carrierName: string | null | undefined,
): number {
  const want = carrierName?.trim().toLowerCase();
  if (!want) return pickLowestCarrierOptionIndex(options);
  const idx = options.findIndex(
    (o) => o.carrierName.trim().toLowerCase() === want,
  );
  return idx >= 0 ? idx : pickLowestCarrierOptionIndex(options);
}

/** 从官网承运商行文案提炼字段 */
export function enrichCarrierOption(raw: {
  label: string;
  rateUsd: number;
}): FlockCarrierOption | null {
  const text = raw.label.replace(/\s+/g, " ").trim();
  if (!text || /Save on average|Don't ship air|Quote shipment again/i.test(text)) {
    return null;
  }
  const transit =
    text.match(/(\d+(?:\s*[–\-]\s*\d+)?)\s*business\s*days?/i)?.[0]?.trim() ||
    text.match(/(\d+)\s*days?/i)?.[0]?.trim() ||
    "";
  const dateRange =
    text.match(
      /((?:Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)[a-z]*\.?\s+\d{1,2}(?:\s*[–\-]\s*(?:(?:Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)[a-z]*\.?\s+)?\d{1,2})?)/i,
    )?.[1]?.trim() || undefined;
  let pickupDate: string | undefined;
  let deliveryEstimate: string | undefined;
  if (dateRange) {
    const parts = dateRange.split(/\s*[–\-]\s*/);
    pickupDate = parts[0]?.trim();
    deliveryEstimate = parts[1]?.trim() || parts[0]?.trim();
  }
  // 承运商名：去掉 Select / 价格 / 时效 / 日期 / 表头噪声后的剩余前缀
  let carrierName = text
    .replace(/Select\s*→?/gi, "")
    .replace(/\$\s*[\d,]+(?:\.\d{1,2})?/g, "")
    .replace(/\d+(?:\s*[–\-]\s*\d+)?\s*business\s*days?/gi, "")
    .replace(
      /(?:Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)[a-z]*\.?\s+\d{1,2}(?:\s*[–\-]\s*(?:(?:Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)[a-z]*\.?\s+)?\d{1,2})?/gi,
      "",
    )
    .replace(
      /\b(Carrier|Transit|from carrier|Pickup|Delivery|estimate|Rate|Select your preferred LTL carrier|Show predictive)\b/gi,
      "",
    )
    .replace(/\s+/g, " ")
    .trim();
  if (!carrierName || carrierName.length < 2) return null;
  if (carrierName.length > 80) carrierName = carrierName.slice(0, 80).trim();
  // 行级祖先偶发吞整表：取最后一个像样的专名片段
  if (/Inc\.?|LLC|Systems|Freight|Air|Lines/i.test(carrierName) && carrierName.length > 40) {
    const parts = carrierName.split(/\s{2,}|\s*\|\s*/).map((p) => p.trim()).filter(Boolean);
    const last = parts[parts.length - 1];
    if (last && last.length >= 3 && last.length <= 60) carrierName = last;
  }
  return {
    carrierName,
    transitDays: transit || "—",
    pickupDate,
    deliveryEstimate,
    rateUsd: raw.rateUsd,
    label: text.slice(0, 200),
  };
}

/** 档内选最低价；同价取首项；空列表返回 -1 */
export function pickLowestRateOptionIndex(
  options: FlockFlexibilityOption[],
): number {
  if (options.length === 0) return -1;
  let best = 0;
  for (let i = 1; i < options.length; i += 1) {
    if (options[i]!.rateUsd < options[best]!.rateUsd) {
      best = i;
    }
  }
  return best;
}

/** 按 key 选档；找不到返回 -1 */
export function pickFlexibilityOptionIndex(
  options: FlockFlexibilityOption[],
  key: FlockFlexibilityKey | null | undefined,
): number {
  if (!key) return pickLowestRateOptionIndex(options);
  const idx = options.findIndex((o) => o.key === key);
  return idx >= 0 ? idx : pickLowestRateOptionIndex(options);
}

export function parseFlockRateUsd(text: string): number | null {
  const m = text.replace(/,/g, "").match(/\$\s*([\d]+(?:\.\d{1,2})?)/);
  if (!m) return null;
  const n = Number(m[1]);
  return Number.isFinite(n) && n > 0 ? n : null;
}

/** 从官网行文案提炼 pickup / deliver */
export function parseFlexibilityWindows(label: string): {
  pickupWindow?: string;
  deliverBy?: string;
} {
  const pickup =
    label.match(/Pickup\s+([A-Za-z0-9–\-\s,]+?)(?:\s+Deliver|$)/i)?.[1]?.trim() ||
    undefined;
  const deliverBy =
    label.match(/Deliver\s+by\s+([A-Za-z0-9–\-\s,]+?)(?:\s+\$|$)/i)?.[1]?.trim() ||
    undefined;
  return { pickupWindow: pickup, deliverBy };
}

export function enrichFlexibilityOption(
  raw: { label: string; rateUsd: number },
): FlockFlexibilityOption | null {
  const key = parseFlockFlexibilityKey(raw.label);
  if (!key) return null;
  const windows = parseFlexibilityWindows(raw.label);
  return {
    key,
    label: raw.label,
    rateUsd: raw.rateUsd,
    ...windows,
  };
}