import fs from 'node:fs';
import { artifactFileExists } from './page-artifact.mjs';
import { hasPlatformBrandMarker } from '../../mindspace-page-tag.mjs';

export { hasPlatformBrandMarker };

const RASTER_IMAGE_PATTERN = /\.(png|jpe?g|webp|gif)(?:[?#]|$)/i;

export function hasMindspaceCoverMeta(html) {
  return /<meta[^>]*name=["']mindspace-cover["']/i.test(String(html ?? ''));
}

export function hasShareDescription(html) {
  const source = String(html ?? '');
  return (
    /<meta[^>]+property=["']og:description["']/i.test(source) ||
    /<meta[^>]+name=["']description["']/i.test(source)
  );
}

export function hasRasterShareImageHint(html) {
  const source = String(html ?? '');
  if (/<meta[^>]+property=["']og:image["'][^>]+content=["'][^"']+/i.test(source)) {
    const match =
      source.match(/<meta[^>]+property=["']og:image["'][^>]+content=["']([^"']+)["']/i) ??
      source.match(/<meta[^>]+content=["']([^"']+)["'][^>]+property=["']og:image["']/i);
    const url = match?.[1] ?? '';
    if (url && !/\.svg(?:[?#]|$)/i.test(url)) return true;
  }
  const coverMatch = source.match(/<meta[^>]*name=["']mindspace-cover["'][^>]*content=(["'])([\s\S]*?)\1/i);
  if (!coverMatch?.[2]) return false;
  try {
    const meta = JSON.parse(coverMatch[2].replaceAll('&quot;', '"'));
    const cover = String(meta.cover ?? meta.image ?? '').trim();
    if (!cover) return false;
    if (/^https?:\/\//i.test(cover)) return RASTER_IMAGE_PATTERN.test(cover);
    return RASTER_IMAGE_PATTERN.test(cover) || !/\.svg(?:[?#]|$)/i.test(cover);
  } catch {
    return false;
  }
}

/**
 * WeChat link cards need mindspace-cover (for thumbnail.png) + description.
 * Visual pages should also reference a raster hero in cover/image when possible.
 */
export function verifySharePreviewMeta(html) {
  if (!hasMindspaceCoverMeta(html)) {
    return { ok: false, reason: 'missing_mindspace_cover' };
  }
  if (!hasShareDescription(html)) {
    return { ok: false, reason: 'missing_description' };
  }
  if (!hasPlatformBrandMarker(html)) {
    return { ok: false, reason: 'missing_platform_brand' };
  }
  return { ok: true, reason: null };
}

export function verifyArtifactSharePreview(artifact) {
  if (!artifactFileExists(artifact)) {
    return { ok: false, reason: 'missing_file' };
  }
  const content = fs.readFileSync(artifact.localPath, 'utf8');
  return verifySharePreviewMeta(content);
}

export function filterSharePreviewReadyArtifacts(artifacts = []) {
  return artifacts.filter((artifact) => verifyArtifactSharePreview(artifact).ok);
}