import fs from 'fs';
import path from 'path';
import { fileURLToPath } from 'url';
import { DatabaseSync } from 'node:sqlite';

const __dirname = path.dirname(fileURLToPath(import.meta.url));
const strapiDbPath = path.join(__dirname, '..', 'strapi-cms', '.tmp', 'data.db');
const strapiUploadsDir = path.join(__dirname, '..', 'strapi-cms', 'public', 'uploads');
const targetPublicUploads = path.join(__dirname, '..', 'public', 'uploads');
const targetServerUploads = path.join(__dirname, '..', 'server', 'uploads');

function syncUploads() {
  try {
    if (!fs.existsSync(strapiUploadsDir)) return;
    if (!fs.existsSync(targetPublicUploads)) fs.mkdirSync(targetPublicUploads, { recursive: true });
    if (!fs.existsSync(targetServerUploads)) fs.mkdirSync(targetServerUploads, { recursive: true });

    const files = fs.readdirSync(strapiUploadsDir);
    files.forEach((f) => {
      if (f === '.gitkeep') return;
      const srcFile = path.join(strapiUploadsDir, f);
      const destPublic = path.join(targetPublicUploads, f);
      const destServer = path.join(targetServerUploads, f);
      if (!fs.existsSync(destPublic)) fs.copyFileSync(srcFile, destPublic);
      if (!fs.existsSync(destServer)) fs.copyFileSync(srcFile, destServer);
    });
  } catch (e) {
    console.warn('Note: Upload sync warning:', e.message);
  }
}

export async function getStrapiBlogs() {
  syncUploads();

  // 1. Primary: Fetch live blogs directly from Strapi REST API (PostgreSQL / Live Strapi DB)
  try {
    const strapiBaseUrl = process.env.STRAPI_URL || 'http://127.0.0.1:1337';
    const response = await fetch(`${strapiBaseUrl}/api/blogs?populate=*`, {
      headers: { 'Accept': 'application/json' },
      signal: AbortSignal.timeout(3000)
    });

    if (response.ok) {
      const json = await response.json();
      const items = json.data || [];

      if (Array.isArray(items) && items.length > 0) {
        const blogs = items.map((b) => {
          let coverUrl = b.coverImage?.url || b.ogImage?.url || null;
          if (!coverUrl) {
            const cat = (b.category || '').toLowerCase();
            if (b.title?.includes('LLM')) coverUrl = '/assets/arvindh_llm_financial.jpg';
            else if (b.title?.includes('Supply Chain')) coverUrl = '/assets/arvindh_supply_chain.jpg';
            else if (b.title?.includes('PRODMAX')) coverUrl = '/assets/prodmax_dashboard.png';
            else if (b.title?.includes('Incidents') || b.title?.includes('VR')) coverUrl = '/assets/whyus_vr_man.jpg';
            else if (b.title?.includes('SCADA') || b.title?.includes('IT/OT')) coverUrl = '/assets/whyus_arab_meeting.jpg';
            else if (b.title?.includes('Cleanroom')) coverUrl = 'https://images.unsplash.com/photo-1592478411213-6153e4ebc07d?auto=format&fit=crop&w=800&q=80';
            else if (b.title?.includes('Spatial') || b.title?.includes('Maintenance')) coverUrl = '/assets/whyus_hologram.jpg';
            else if (b.title?.includes('Energy')) coverUrl = '/assets/whyus_teamwork.png';
            else if (b.title?.includes('Telemetry') || b.title?.includes('Sensor')) coverUrl = 'https://images.unsplash.com/photo-1581091226825-a6a2a5aee158?auto=format&fit=crop&w=800&q=80';
            else if (b.title?.includes('Monoliths') || b.title?.includes('Micro-Frontends')) coverUrl = 'https://images.unsplash.com/photo-1519389950473-47ba0277781c?auto=format&fit=crop&w=800&q=80';
            else if (b.title?.includes('Zero-Trust')) coverUrl = 'https://images.unsplash.com/photo-1563986768494-4dee2763ff3f?auto=format&fit=crop&w=800&q=80';
            else if (b.title?.includes('Multi-Cloud')) coverUrl = 'https://images.unsplash.com/photo-1544197150-b99a580bb7a8?auto=format&fit=crop&w=800&q=80';
            else if (cat.includes('ai')) coverUrl = '/assets/arvindh_agentic_ai.jpg';
            else coverUrl = 'https://images.unsplash.com/photo-1519389950473-47ba0277781c?auto=format&fit=crop&w=800&q=80';
          }

          const rawDate = b.publishDate || b.publishedAt || b.createdAt;
          const dateStr = rawDate
            ? new Date(rawDate).toLocaleDateString('en-US', { month: 'short', day: '2-digit', year: 'numeric' })
            : new Date().toLocaleDateString('en-US', { month: 'short', day: '2-digit', year: 'numeric' });

          return {
            id: b.id || b.documentId,
            documentId: b.documentId,
            category: b.category || 'Technology',
            title: b.title,
            excerpt: b.excerpt || '',
            content: b.content || '',
            readTime: b.readTime || '5 min read',
            date: dateStr,
            image: coverUrl,
            slug: b.slug,
            author: (typeof b.authorName === 'string' && b.authorName.trim())
              ? b.authorName.trim()
              : (typeof b.author === 'string' && b.author.trim()
                  ? b.author.trim()
                  : (b.author?.firstname ? `${b.author.firstname} ${b.author.lastname || ''}`.trim() : (b.author?.username || 'Cavin Editorial Team'))),
            authorDesignation: b.authorDesignation || 'Chief AI Architect & Head of Data Engineering',
            editor: (typeof b.editorName === 'string' && b.editorName.trim())
              ? b.editorName.trim()
              : (typeof b.editor === 'string' && b.editor.trim()
                  ? b.editor.trim()
                  : (b.editor?.firstname ? `${b.editor.firstname} ${b.editor.lastname || ''}`.trim() : (b.editor?.username || null))),
            editorDesignation: b.editorDesignation || null,
            tags: b.tags || [],
            metaTitle: b.metaTitle || null,
            metaDescription: b.metaDescription || null,
            keywords: b.keywords || null,
            canonicalURL: b.canonicalURL || null
          };
        });

        if (blogs.length > 0) return blogs;
      }
    }
  } catch (apiErr) {
    console.warn('Note: Live Strapi REST API fetch bypassed/failed, trying SQLite fallback:', apiErr.message);
  }

  // 2. Fallback: SQLite `.tmp/data.db` if Strapi API is offline
  try {
    if (!fs.existsSync(strapiDbPath)) return null;
    const db = new DatabaseSync(strapiDbPath);
    const rows = db.prepare('SELECT * FROM blogs WHERE published_at IS NOT NULL ORDER BY id ASC').all();
    const mediaLinks = db.prepare("SELECT * FROM files_related_mph WHERE related_type = 'api::blog.blog'").all();
    const files = db.prepare('SELECT * FROM files').all();
    const adminUsers = db.prepare('SELECT id, firstname, lastname FROM admin_users').all();

    const userMap = {};
    adminUsers.forEach((u) => {
      userMap[u.id] = `${u.firstname || ''} ${u.lastname || ''}`.trim();
    });

    const seenSlugs = new Set();
    const blogs = [];

    rows.forEach((b) => {
      if (!b.title || b.title.toLowerCase().startsWith('test 3')) return;
      if (seenSlugs.has(b.slug)) return;
      seenSlugs.add(b.slug);

      const link = mediaLinks.find((l) => l.related_id === b.id);
      const file = link ? files.find((f) => f.id === link.file_id) : null;
      let image = file ? file.url : null;

      if (!image) {
        const cat = (b.category || '').toLowerCase();
        if (b.title.includes('LLM')) image = '/assets/arvindh_llm_financial.jpg';
        else if (b.title.includes('Supply Chain')) image = '/assets/arvindh_supply_chain.jpg';
        else if (b.title.includes('PRODMAX')) image = '/assets/prodmax_dashboard.png';
        else if (b.title.includes('Incidents') || b.title.includes('VR')) image = '/assets/whyus_vr_man.jpg';
        else if (b.title.includes('SCADA') || b.title.includes('IT/OT')) image = '/assets/whyus_arab_meeting.jpg';
        else if (b.title.includes('Cleanroom')) image = 'https://images.unsplash.com/photo-1592478411213-6153e4ebc07d?auto=format&fit=crop&w=800&q=80';
        else if (b.title.includes('Spatial') || b.title.includes('Maintenance')) image = '/assets/whyus_hologram.jpg';
        else if (b.title.includes('Energy')) image = '/assets/whyus_teamwork.png';
        else if (b.title.includes('Telemetry') || b.title.includes('Sensor')) image = 'https://images.unsplash.com/photo-1581091226825-a6a2a5aee158?auto=format&fit=crop&w=800&q=80';
        else if (b.title.includes('Monoliths') || b.title.includes('Micro-Frontends')) image = 'https://images.unsplash.com/photo-1519389950473-47ba0277781c?auto=format&fit=crop&w=800&q=80';
        else if (b.title.includes('Zero-Trust')) image = 'https://images.unsplash.com/photo-1563986768494-4dee2763ff3f?auto=format&fit=crop&w=800&q=80';
        else if (b.title.includes('Multi-Cloud')) image = 'https://images.unsplash.com/photo-1544197150-b99a580bb7a8?auto=format&fit=crop&w=800&q=80';
        else if (cat.includes('ai')) image = '/assets/arvindh_agentic_ai.jpg';
        else image = 'https://images.unsplash.com/photo-1519389950473-47ba0277781c?auto=format&fit=crop&w=800&q=80';
      }

      const dateStr = b.published_at
        ? new Date(Number(b.published_at)).toLocaleDateString('en-US', { month: 'short', day: '2-digit', year: 'numeric' })
        : new Date(Number(b.created_at || Date.now())).toLocaleDateString('en-US', { month: 'short', day: '2-digit', year: 'numeric' });

      const author = userMap[b.created_by_id] || 'Dr. Arvindh Ramachandran';
      const authorRole = b.author_designation || 'Chief AI Architect & Head of Data Engineering';
      const hasEditor = Boolean(b.editor_designation || (b.updated_by_id && b.updated_by_id !== b.created_by_id));
      const editor = hasEditor ? (userMap[b.updated_by_id] && userMap[b.updated_by_id] !== author ? userMap[b.updated_by_id] : 'Cavin Editorial Board') : null;
      const editorRole = b.editor_designation || (hasEditor ? 'Senior Technical Reviewer' : null);

      blogs.push({
        id: b.id,
        category: b.category || 'Technology',
        title: b.title,
        excerpt: b.excerpt || '',
        content: b.content || '',
        readTime: b.read_time || '5 min read',
        date: dateStr,
        image,
        slug: b.slug,
        author,
        authorDesignation: authorRole,
        editor,
        editorDesignation: editorRole,
        tags: b.tags ? JSON.parse(b.tags) : []
      });
    });

    return blogs.length > 0 ? blogs : null;
  } catch (err) {
    console.warn('Note: Strapi SQLite DB sync check bypassed:', err.message);
    return null;
  }
}