/**
 * 콘텐츠관리 목록의 필터·검색·정렬·페이징 조건 — 세 화면이 같은 규칙을 쓴다.
 * URL(searchParams)이 단일 진실원천이며 next/react 의존이 없다.
 */

import { CONTENT_KIND_LABEL, type ContentKind } from '@/lib/domain/content';

export const CONTENT_PATH: Record<ContentKind, string> = {
  shorts: '/contents/shorts',
  quiz: '/contents/quizzes',
  comic: '/contents/comics',
};

export function contentListPath(kind: ContentKind): string {
  return CONTENT_PATH[kind];
}

export function contentCreatePath(kind: ContentKind): string {
  return `${CONTENT_PATH[kind]}/new`;
}

export function contentEditPath(kind: ContentKind, id: string): string {
  return `${CONTENT_PATH[kind]}/${encodeURIComponent(id)}`;
}

export function contentBreadcrumb(
  kind: ContentKind,
  leaf?: string
): Array<{ label: string; href?: string }> {
  const trail: Array<{ label: string; href?: string }> = [
    { label: '홈', href: '/' },
    { label: '콘텐츠관리' },
  ];
  if (leaf) {
    trail.push({ label: CONTENT_KIND_LABEL[kind], href: CONTENT_PATH[kind] });
    trail.push({ label: leaf });
  } else {
    trail.push({ label: CONTENT_KIND_LABEL[kind] });
  }
  return trail;
}

export type ContentSortOption = 'created' | 'modified';

export const CONTENT_SORT_OPTIONS: ReadonlyArray<{
  value: ContentSortOption;
  label: string;
}> = [
  { value: 'created', label: '최신등록일순' },
  { value: 'modified', label: '최신수정일순' },
];

/** 기획 "리스트 — 최신 등록일 순으로 정렬". */
export const DEFAULT_CONTENT_SORT: ContentSortOption = 'created';

export const CONTENT_PAGE_SIZE_OPTIONS = [10, 30, 50] as const;
export type ContentPageSize = (typeof CONTENT_PAGE_SIZE_OPTIONS)[number];
export const DEFAULT_CONTENT_PAGE_SIZE: ContentPageSize = 10;

export type ContentSearchFieldOption = { value: string; label: string };

/** 검색 대상 — 기획의 화면별 문구 그대로. */
export const CONTENT_SEARCH_FIELDS: Record<
  ContentKind,
  readonly ContentSearchFieldOption[]
> = {
  shorts: [
    { value: 'title', label: '제목' },
    { value: 'keyword', label: '키워드' },
  ],
  // 백엔드 목록 SQL이 이름이 바뀌기 전 컬럼(QUIZ_ANSWER·QUIZ_QUESTION)을 보고 있어, 검색어를
  // 실으면 목록 조회가 SQL 오류로 죽는다. 고쳐질 때까지 감춘다(사용자 확정).
  quiz: [],
  comic: [
    { value: 'name', label: '콘텐츠명' },
    { value: 'keyword', label: '키워드' },
  ],
};

const DEFAULT_PAGE = 1;
const MAX_KEYWORD_LENGTH = 100;

export type ContentQuery = {
  /** 공통코드 `COM_SCHUL_CD` 코드값. 빈 값이면 전체. */
  school: string;
  /** 공통코드 `GRD_CD` 코드값. 빈 값이면 전체. */
  grade: string;
  /** 금융OX퀴즈 전용 난이도 필터. 다른 화면에서는 늘 빈 값이다. */
  level: string;
  searchField: string;
  keyword: string;
  sort: ContentSortOption;
  page: number;
  pageSize: ContentPageSize;
};

type RawSearchParams = Record<string, string | string[] | undefined>;

function readParam(params: RawSearchParams, key: string): string {
  const value = params[key];
  const raw = Array.isArray(value) ? value[0] : value;
  return (raw ?? '').trim();
}

export function parseContentQuery(
  kind: ContentKind,
  searchParams: RawSearchParams
): ContentQuery {
  const fields = CONTENT_SEARCH_FIELDS[kind];
  const searchField = readParam(searchParams, 'searchField');
  const sort = readParam(searchParams, 'sort');
  const page = Number(readParam(searchParams, 'page'));
  const pageSize = Number(readParam(searchParams, 'pageSize'));

  return {
    school: readParam(searchParams, 'school'),
    grade: readParam(searchParams, 'grade'),
    level: kind === 'quiz' ? readParam(searchParams, 'level') : '',
    // 검색 대상이 하나도 없을 수 있다(백엔드가 못 거르는 화면은 감춘다) — 그때는 빈 값이다.
    searchField: fields.some((field) => field.value === searchField)
      ? searchField
      : (fields[0]?.value ?? ''),
    keyword: readParam(searchParams, 'keyword').slice(0, MAX_KEYWORD_LENGTH),
    sort: sort === 'modified' ? 'modified' : DEFAULT_CONTENT_SORT,
    page: Number.isInteger(page) && page > 0 ? page : DEFAULT_PAGE,
    pageSize: (CONTENT_PAGE_SIZE_OPTIONS as readonly number[]).includes(pageSize)
      ? (pageSize as ContentPageSize)
      : DEFAULT_CONTENT_PAGE_SIZE,
  };
}

export function buildContentHref(
  kind: ContentKind,
  query: ContentQuery,
  overrides: Partial<ContentQuery> = {}
): string {
  const merged = { ...query, ...overrides };
  const params = new URLSearchParams();
  // 검색 대상이 없는 화면(금융OX퀴즈)은 기본값도 없다 — 그때는 주소에 싣지 않는다.
  const defaultField = CONTENT_SEARCH_FIELDS[kind][0]?.value ?? '';

  if (merged.school) params.set('school', merged.school);
  if (merged.grade) params.set('grade', merged.grade);
  if (merged.level) params.set('level', merged.level);
  if (merged.searchField && merged.searchField !== defaultField) {
    params.set('searchField', merged.searchField);
  }
  if (merged.keyword) params.set('keyword', merged.keyword);
  if (merged.sort !== DEFAULT_CONTENT_SORT) params.set('sort', merged.sort);
  if (merged.pageSize !== DEFAULT_CONTENT_PAGE_SIZE) {
    params.set('pageSize', String(merged.pageSize));
  }
  if (merged.page !== DEFAULT_PAGE) params.set('page', String(merged.page));

  const queryString = params.toString();
  return queryString
    ? `${CONTENT_PATH[kind]}?${queryString}`
    : CONTENT_PATH[kind];
}