/**
 * 卖价/买价重量因素：左开右闭区间 (start, end]。
 * 界面与快照统一存为 (0-0.5] 形式，便于 0.312 等重量命中。
 */

/** 重量因素值下拉：0.5 步进至 30，其后固定 999（卖价/买价共用） */
export function buildWeightFactorSelectOptions(): Array<{ label: string; value: string }> {
  return [
    ...Array.from({ length: 60 }, (_, index) => {
      const v = ((index + 1) * 0.5).toFixed(1).replace(/\.0$/, '');
      return { label: v, value: v };
    }),
    { label: '999', value: '999' },
  ];
}

export function isWeightPricingFactor(factorKey: string): boolean {
  const k = String(factorKey ?? '').trim();
  if (!k) return false;
  if (k === '重量' || k === 'weight') return true;
  return false;
}

/** 解析重量单元格或因素值为区间上下界；单值 0.5 视为 (0, 0.5]。 */
export function parseWeightIntervalBounds(text: string): { start: number; end: number } | null {
  const trimmed = String(text ?? '').trim();
  if (!trimmed) return null;

  const stripped = trimmed.replace(/^\(/, '').replace(/\]$/, '').replace(/^\[/, '');
  const parts = stripped
    .split(/[,，\-~～]/)
    .map((s) => s.trim())
    .filter(Boolean);

  if (parts.length >= 2) {
    const start = Number.parseFloat(parts[0]);
    const end = Number.parseFloat(parts[1]);
    if (Number.isFinite(start) && Number.isFinite(end) && end > start) {
      return { start, end };
    }
  }

  const single = Number.parseFloat(parts[0] ?? stripped);
  if (Number.isFinite(single) && single > 0) {
    return { start: 0, end: single };
  }

  return null;
}

function formatWeightNumber(n: number): string {
  const s = n.toFixed(4).replace(/\.?0+$/, '');
  return s === '' ? '0' : s;
}

/** 格式化为 (start-end] 展示与存储。 */
export function formatWeightIntervalLeftOpenRightClosed(start: number, end: number): string {
  return `(${formatWeightNumber(start)}-${formatWeightNumber(end)}]`;
}

/** 将单值或旧格式转为区间字符串 (start-end]。 */
export function weightValueToIntervalCell(
  rawValue: string,
  allWeightValuesInFactor: string[]
): string {
  const trimmed = String(rawValue ?? '').trim();
  if (!trimmed) return '';

  const parsed = parseWeightIntervalBounds(trimmed);
  if (
    parsed &&
    (trimmed.includes('-') || trimmed.includes(',') || trimmed.includes('，') || trimmed.includes(']'))
  ) {
    return formatWeightIntervalLeftOpenRightClosed(parsed.start, parsed.end);
  }

  const bounds = weightFactorValuesToSortedUpperBounds(allWeightValuesInFactor);
  const end = Number.parseFloat(trimmed);
  if (!Number.isFinite(end)) return trimmed;

  const idx = bounds.findIndex((n) => Math.abs(n - end) < 1e-9);
  const start = idx > 0 ? bounds[idx - 1]! : 0;
  const upper = idx >= 0 ? bounds[idx]! : end;
  return formatWeightIntervalLeftOpenRightClosed(start, upper);
}

function factorValueSortNumber(v: string): number | null {
  const parsed = parseWeightIntervalBounds(v);
  if (parsed) return parsed.end;
  const n = Number.parseFloat(String(v).trim());
  return Number.isFinite(n) ? n : null;
}

/** 按数值大小升序排列因素值（如 2, 0.5, 1 → 0.5, 1, 2）。 */
export function sortFactorValuesBySize(values: string[] | undefined): string[] {
  return [...(values ?? [])].sort((a, b) => {
    const na = factorValueSortNumber(String(a));
    const nb = factorValueSortNumber(String(b));
    if (na != null && nb != null && na !== nb) return na - nb;
    if (na != null && nb == null) return -1;
    if (na == null && nb != null) return 1;
    return String(a).localeCompare(String(b), undefined, { numeric: true, sensitivity: 'base' });
  });
}

/** 提取因素值列表中的重量上限并升序排列（用于区间左界）。 */
export function weightFactorValuesToSortedUpperBounds(values: string[]): number[] {
  const nums = (values ?? [])
    .map((v) => factorValueSortNumber(v))
    .filter((n): n is number => n != null);
  return [...new Set(nums)].sort((a, b) => a - b);
}

/** 提交快照/API 时规范化重量单元格。 */
export function canonicalWeightFactorCellForApi(
  rawValue: string,
  allWeightValuesInFactor: string[]
): string {
  return weightValueToIntervalCell(rawValue, allWeightValuesInFactor);
}