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

/**
 * 与后端 `CHAPTER_ORDER` / `CHAPTER_CATEGORIES` 顺序一致；对应 i18n `memoir.frameworkChapters.*`。
 */
export const FRAMEWORK_CHAPTER_KEYS = [
  'chapter1',
  'chapter2',
  'chapter3',
  'chapter4',
  'chapter5',
  'chapter6',
  'chapter7',
  'chapter8',
] as const;

export type FrameworkChapterKey = (typeof FRAMEWORK_CHAPTER_KEYS)[number];

/** 与后端 `CHAPTER_ORDER` 一致（用于占位章节缺省 category） */
export const CHAPTER_CATEGORY_BY_ORDER_INDEX = [
  'childhood',
  'education',
  'career_early',
  'career_achievement',
  'career_challenge',
  'family',
  'beliefs',
  'summary',
] as const;

export function buildFrameworkChapterPlaceholders(
  tr: (key: string) => string,
): ChapterViewModel[] {
  return FRAMEWORK_CHAPTER_KEYS.map((key, orderIndex) => ({
    id: `framework:${key}`,
    title: tr(`frameworkChapters.${key}`),
    category: '',
    orderIndex,
    isEmpty: true,
    isNew: false,
    hasImages: false,
    allImagesReady: false,
    pendingImageCount: 0,
    failedImageCount: 0,
    coverImageUrl: null,
    updatedAt: null,
    wordCount: 0,
  }));
}

/**
 * 列表页始终展示 8 个框架槽位：已有章节用接口数据，其余槽位仍用框架占位（与「零章节」时一致）。
 */
export function mergeFrameworkChaptersWithFetched(
  placeholders: ChapterViewModel[],
  fetched: ChapterViewModel[],
): ChapterViewModel[] {
  const byOrder = new Map<number, ChapterViewModel>();
  for (const vm of fetched) {
    byOrder.set(vm.orderIndex, vm);
  }
  return placeholders.map((p) => byOrder.get(p.orderIndex) ?? p);
}