import { readFileSync } from 'node:fs';
import { join } from 'node:path';

import { markdownToDoc } from '@dorfteich/shared';
import { beforeAll, describe, expect, it, TestContext } from 'vitest';

import { AppConfig } from '../config/app-config.service';

import { convertImportedDocument } from './import.service';
import { CONVERSION_TIMEOUT_MS, PandocServerConverter } from './pandoc.converter';

/**
 * Import fidelity regression (issue #63, ADR 0009): runs the real two-pass
 * pandoc conversion over the committed `.docx`/`.odt` corpus and asserts each
 * produces its expected Markdown. Needs a reachable pandoc sidecar (the pinned
 * `pandoc/core:3.6`, so output matches the snapshots) — each test skips itself
 * when none is configured, and CI starts one and points `PANDOC_URL` at it.
 */
const PANDOC_URL = process.env.PANDOC_URL ?? 'http://localhost:3030';
// The test runner's cwd is `apps/api`; the corpus lives at the repo root.
const FIXTURES = join(process.cwd(), '../../fixtures/import');

const converter = new PandocServerConverter({
  env: { PANDOC_URL },
} as unknown as AppConfig);

let reachable = false;

/** Normalise embedded image `data:` URIs to the stable token the snapshots use
 * (the base64 payload is volatile and not what we are pinning). */
function normalize(markdown: string): string {
  return markdown.replace(
    /data:image\/[a-zA-Z0-9.+-]+;base64,[A-Za-z0-9+/=]+/g,
    'data:embedded-image',
  );
}

const CORPUS = ['article.docx', 'article.odt', 'formatting.docx', 'formatting.odt'];

describe('import fixture corpus (real pandoc, issue #63)', () => {
  beforeAll(async () => {
    reachable = await converter.reachable().catch(() => false);
  });

  for (const fixture of CORPUS) {
    it(`converts ${fixture} to its expected Markdown`, async (ctx: TestContext) => {
      if (!reachable) ctx.skip();
      const format = fixture.endsWith('.odt') ? 'odt' : 'docx';
      const document = readFileSync(join(FIXTURES, fixture));
      const expected = readFileSync(join(FIXTURES, `${fixture}.expected.md`), 'utf8');

      const markdown = await convertImportedDocument(converter, format, document);
      expect(normalize(markdown)).toBe(expected);

      // The Markdown must also parse into a valid editor document (no schema
      // surprises from real-world structure).
      expect(() => markdownToDoc(markdown)).not.toThrow();
    });
  }

  it('imports a 50-page document within the conversion timeout', async (ctx: TestContext) => {
    if (!reachable) ctx.skip();
    // Build a ~50-page document by repeating a page of structured content, then
    // convert it to docx once and time the import conversion of that document.
    const onePage =
      '# Section\n\n' + 'A paragraph of survey notes about the pond. '.repeat(20) + '\n\n';
    const large = Array.from({ length: 50 }, () => onePage).join('\n---\n\n');
    const docx = await converter.convert({ from: 'gfm', to: 'docx', input: Buffer.from(large) });

    const started = Date.now();
    const markdown = await convertImportedDocument(converter, 'docx', docx.output);
    const elapsed = Date.now() - started;

    expect(markdown.length).toBeGreaterThan(1000);
    // Comfortably inside the documented 60 s per-conversion ceiling (ADR 0009).
    expect(elapsed).toBeLessThan(CONVERSION_TIMEOUT_MS);
  });
});