import { getPayload } from 'payload';
import configPromise from '@payload-config';
import fs from 'fs';
import path from 'path';
import matter from 'gray-matter';
import { parseMarkdownToLexical } from '../src/payload/utils/lexicalParser';

async function mapImageToMediaId(payload: any, imagePath: string): Promise<string | null> {
  if (!imagePath) return null;
  const filename = path.basename(imagePath);

  const media = await payload.find({
    collection: 'media',
    where: {
      filename: {
        equals: filename,
      },
    },
    limit: 1,
  });

  if (media.docs.length > 0) {
    return media.docs[0].id;
  }

  // Auto-ingest missing images from legacy public/ directory
  const cleanPath = imagePath.startsWith('/') ? imagePath.slice(1) : imagePath;
  const fullPath = path.join(process.cwd(), 'public', cleanPath);

  if (fs.existsSync(fullPath)) {
    try {
      console.log(`[Blog Migration] 📤 Ingesting missing Media into Payload: ${filename}`);
      const newMedia = await payload.create({
        collection: 'media',
        data: {
          alt: filename.replace(/[-_]/g, ' ').replace(/\.[^/.]+$/, ''), // create a human readable alt text
        },
        filePath: fullPath,
      });
      return newMedia.id;
    } catch (err: any) {
      console.error(`[Blog Migration] ❌ Failed to ingest ${filename}:`, err);
    }
  } else {
    console.warn(`[Blog Migration] ⚠️ Missing image entirely from disk: ${fullPath}`);
  }
  return null;
}

async function migrateBlogPages() {
  const payload = await getPayload({ config: configPromise });

  const locales = ['en', 'de'];
  for (const locale of locales) {
    const pagesDir = path.join(process.cwd(), 'data', 'pages', locale);
    if (!fs.existsSync(pagesDir)) continue;

    const files = fs.readdirSync(pagesDir);
    for (const file of files) {
      if (!file.endsWith('.mdx')) continue;

      const slug = file.replace(/\.mdx$/, '');
      const filePath = path.join(pagesDir, file);
      const fileContent = fs.readFileSync(filePath, 'utf8');
      const { data, content } = matter(fileContent);

      console.log(`Migrating ${locale}/${slug}...`);

      const lexicalBlocks = parseMarkdownToLexical(content);
      const lexicalAST = {
        root: {
          type: 'root',
          format: '',
          indent: 0,
          version: 1,
          children: lexicalBlocks,
          direction: 'ltr',
        },
      };

      const status = data.public === false ? 'draft' : 'published';

      let featuredImageId = null;
      if (data.featuredImage || data.image) {
        featuredImageId = await mapImageToMediaId(payload, data.featuredImage || data.image);
      }

      try {
        // Find existing post
        const existing = await payload.find({
          collection: 'pages',
          where: { slug: { equals: slug }, locale: { equals: locale } as any },
        });

        if (slug.includes('welcome-to-the-future')) {
          console.log(`\n--- AST for ${slug} ---`);
          console.log(JSON.stringify(lexicalAST, null, 2));
          console.log(`-----------------------\n`);
        }

        if (existing.docs.length > 0) {
          await payload.update({
            collection: 'pages',
            id: existing.docs[0].id,
            data: {
              content: lexicalAST as any,
              ...(featuredImageId ? { featuredImage: featuredImageId } : {}),
            },
          });
          console.log(`✅ AST Components & Image RE-INJECTED for ${slug}`);
        } else {
          await payload.create({
            collection: 'pages',
            data: {
              title: data.title,
              slug: slug,
              locale: locale,
              excerpt: data.excerpt || '',
              content: lexicalAST as any,
              ...(featuredImageId ? { featuredImage: featuredImageId } : {}),
            },
          });
          console.log(`✅ Created ${slug}`);
        }
      } catch (err: any) {
        console.error(`❌ Failed ${slug}`, err.message);
      }
    }
  }

  console.log('Migration completed.');
  process.exit(0);
}

migrateBlogPages().catch(console.error);