import type { Issue } from '../types';

export interface AbutImportIssueGroup {
  name?: string;
  primary: Issue[];
  related: Issue[];
}

/** Keep root errors visible while retaining every dependent row in a disclosure. */
export function groupAbutImportIssues(issues: readonly Issue[]): AbutImportIssueGroup[] {
  const groups: { name?: string; issues: Issue[] }[] = [];
  const byName = new Map<string, { name: string; issues: Issue[] }>();
  for (const issue of issues) {
    if (issue.pier === undefined) {
      groups.push({ issues: [issue] });
      continue;
    }
    let group = byName.get(issue.pier);
    if (!group) {
      group = { name: issue.pier, issues: [] };
      byName.set(issue.pier, group);
      groups.push(group);
    }
    group.issues.push(issue);
  }
  return groups.map(({ name, issues: items }) => {
    const primary = items.filter((issue) => issue.code !== 'AP04');
    const related = items.filter((issue) => issue.code === 'AP04');
    if (!primary.length && related.length) primary.push({
      ...related[0],
      message: `교대 ${name ?? ''}: 교대 정보 행이 없어 IP·받침 ${related.length}개 행을 연결하지 못했습니다. 전체 교대명을 확인하세요.`,
    });
    return { name, primary, related };
  });
}