import { toChapterViewModel } from '@/features/memoir/mappers';
import type { Chapter, ImageAsset } from '@/features/memoir/types';

function makeImage(overrides: Partial<ImageAsset> = {}): ImageAsset {
  return {
    placeholder: 'img_1',
    description: 'A scene',
    index: 0,
    status: 'completed',
    prompt: null,
    url: 'https://example.com/img.jpg',
    provider: null,
    style: null,
    size: null,
    error: null,
    retryable: null,
    created_at: null,
    updated_at: null,
    ...overrides,
  };
}

function makeChapter(overrides: Partial<Chapter> = {}): Chapter {
  return {
    id: 'ch-1',
    title: '童年',
    order_index: 0,
    status: 'ready',
    category: 'childhood',
    images: [],
    cover_asset: null,
    canonical_markdown: '段落1',
    updated_at: '2026-01-01T00:00:00Z',
    is_new: false,
    source_segments: [],
    ...overrides,
  };
}

describe('toChapterViewModel', () => {
  test('maps basic chapter fields', () => {
    const vm = toChapterViewModel(makeChapter());

    expect(vm.id).toBe('ch-1');
    expect(vm.title).toBe('童年');
    expect(vm.category).toBe('childhood');
    expect(vm.orderIndex).toBe(0);
    expect(vm.isEmpty).toBe(false);
    expect(vm.isNew).toBe(false);
    expect(vm.wordCount).toBe('段落1'.length);
  });

  test('uses word_count from API when canonical markdown exists', () => {
    const vm = toChapterViewModel(
      makeChapter({
        word_count: 1200,
        canonical_markdown: 'x'.repeat(1200),
      }),
    );
    expect(vm.wordCount).toBe(1200);
  });

  test('uses cover_asset from list payload', () => {
    const cover = makeImage({ url: 'https://example.com/from-asset.jpg' });
    const vm = toChapterViewModel(
      makeChapter({ cover_asset: cover, images: [] }),
    );
    expect(vm.coverImageUrl).toBe('https://example.com/from-asset.jpg');
    expect(vm.hasImages).toBe(true);
  });

  test('detects empty chapters', () => {
    const vm = toChapterViewModel(makeChapter({ canonical_markdown: '' }));
    expect(vm.isEmpty).toBe(true);
  });

  test('uses canonical_markdown for isEmpty when present', () => {
    const vm = toChapterViewModel(
      makeChapter({
        status: 'ready',
        canonical_markdown: '# 童年\n\n一段回忆。',
      }),
    );
    expect(vm.isEmpty).toBe(false);
  });

  test('derives image status counts correctly', () => {
    const images = [
      makeImage({ status: 'completed' }),
      makeImage({ status: 'pending' }),
      makeImage({ status: 'processing' }),
      makeImage({ status: 'failed' }),
    ];

    const vm = toChapterViewModel(makeChapter({ images }));

    expect(vm.hasImages).toBe(true);
    expect(vm.allImagesReady).toBe(false);
    expect(vm.pendingImageCount).toBe(2);
    expect(vm.failedImageCount).toBe(1);
  });

  test('allImagesReady is true when all completed', () => {
    const images = [
      makeImage({ status: 'completed' }),
      makeImage({ status: 'completed' }),
    ];

    const vm = toChapterViewModel(makeChapter({ images }));

    expect(vm.allImagesReady).toBe(true);
    expect(vm.pendingImageCount).toBe(0);
    expect(vm.failedImageCount).toBe(0);
  });

  test('extracts cover image URL', () => {
    const cover = makeImage({ url: 'https://example.com/cover.jpg' });
    const vm = toChapterViewModel(makeChapter({ cover_asset: cover }));

    expect(vm.coverImageUrl).toBe('https://example.com/cover.jpg');
  });

  test('cover image URL is null when no cover', () => {
    const vm = toChapterViewModel(makeChapter({ cover_asset: null }));
    expect(vm.coverImageUrl).toBeNull();
  });
});