/**
 * Main API Worker for Rocky Mountain Vending
 * 
 * This worker handles all API endpoints:
 * - /api/manuals/* - Serve PDF manuals from R2
 * - /api/thumbnails/* - Serve thumbnail images from R2
 * - /api/sitemap-submit - Submit sitemap to Google Search Console
 * - /api/request-indexing - Request URL indexing
 * - /health - Health check endpoint
 * 
 * Account ID: bd6f76304a840ba11b75f9ced84264f4
 * Temp subdomain: matt-bd6.workers.dev
 */

export interface Env {
  // R2 bucket bindings
  MANUALS_BUCKET: R2Bucket;
  THUMBNAILS_BUCKET: R2Bucket;
  
  // Google Search Console credentials (optional)
  GOOGLE_SERVICE_ACCOUNT_EMAIL?: string;
  GOOGLE_PRIVATE_KEY?: string;
  GOOGLE_SITE_URL?: string;
  
  // Site configuration
  SITE_URL?: string;
  SITE_DOMAIN?: string;
  
  // CORS configuration
  ALLOWED_ORIGINS?: string;
}

const CORS_HEADERS = {
  'Access-Control-Allow-Origin': '*',
  'Access-Control-Allow-Methods': 'GET, POST, OPTIONS',
  'Access-Control-Allow-Headers': 'Content-Type, Authorization',
};

export default {
  async fetch(request: Request, env: Env): Promise<Response> {
    const url = new URL(request.url);
    const pathname = url.pathname;

    // Handle CORS preflight
    if (request.method === 'OPTIONS') {
      return new Response(null, {
        headers: CORS_HEADERS,
      });
    }

    // Route requests
    if (pathname.startsWith('/api/manuals/')) {
      return handleManuals(request, env, url);
    }
    
    if (pathname.startsWith('/api/thumbnails/')) {
      return handleThumbnails(request, env, url);
    }
    
    if (pathname === '/api/sitemap-submit') {
      return handleSitemapSubmit(request, env);
    }
    
    if (pathname === '/api/request-indexing') {
      return handleRequestIndexing(request, env);
    }
    
    if (pathname === '/health') {
      return handleHealth(env);
    }

    return new Response('Not found', { 
      status: 404,
      headers: CORS_HEADERS,
    });
  },
};

/**
 * Handle manual PDF requests from R2
 */
async function handleManuals(request: Request, env: Env, url: URL): Promise<Response> {
  if (request.method !== 'GET') {
    return new Response('Method not allowed', { 
      status: 405,
      headers: CORS_HEADERS,
    });
  }

  // Extract path from /api/manuals/...
  const pathMatch = url.pathname.match(/^\/api\/manuals\/(.+)$/);
  if (!pathMatch) {
    return new Response('Invalid path', { 
      status: 400,
      headers: CORS_HEADERS,
    });
  }

  const filePath = decodeURIComponent(pathMatch[1]);
  
  // Security: Prevent directory traversal
  if (filePath.includes('..') || filePath.startsWith('/')) {
    return new Response('Invalid path', { 
      status: 400,
      headers: CORS_HEADERS,
    });
  }

  // Only allow PDF files
  if (!filePath.toLowerCase().endsWith('.pdf')) {
    return new Response('Invalid file type', { 
      status: 400,
      headers: CORS_HEADERS,
    });
  }

  try {
    const object = await env.MANUALS_BUCKET.get(filePath);
    
    if (!object) {
      return new Response('File not found', { 
        status: 404,
        headers: CORS_HEADERS,
      });
    }

    const filename = filePath.split('/').pop() || 'manual.pdf';
    const headers = new Headers(CORS_HEADERS);
    headers.set('Content-Type', 'application/pdf');
    headers.set('Content-Disposition', `inline; filename="${encodeURIComponent(filename)}"`);
    headers.set('Cache-Control', 'public, max-age=31536000, immutable');
    headers.set('X-Content-Type-Options', 'nosniff');

    return new Response(object.body, { headers });
  } catch (error) {
    console.error('Error serving manual:', error);
    return new Response(
      JSON.stringify({ 
        error: 'Failed to serve manual',
        message: error instanceof Error ? error.message : 'Unknown error'
      }),
      { 
        status: 500,
        headers: { ...CORS_HEADERS, 'Content-Type': 'application/json' },
      }
    );
  }
}

/**
 * Handle thumbnail image requests from R2
 */
async function handleThumbnails(request: Request, env: Env, url: URL): Promise<Response> {
  if (request.method !== 'GET') {
    return new Response('Method not allowed', { 
      status: 405,
      headers: CORS_HEADERS,
    });
  }

  // Extract path from /api/thumbnails/...
  const pathMatch = url.pathname.match(/^\/api\/thumbnails\/(.+)$/);
  if (!pathMatch) {
    return new Response('Invalid path', { 
      status: 400,
      headers: CORS_HEADERS,
    });
  }

  const filePath = decodeURIComponent(pathMatch[1]);
  
  // Security: Prevent directory traversal
  if (filePath.includes('..') || filePath.startsWith('/')) {
    return new Response('Invalid path', { 
      status: 400,
      headers: CORS_HEADERS,
    });
  }

  // Only allow image files
  const lowerPath = filePath.toLowerCase();
  const allowedExtensions = ['.jpg', '.jpeg', '.png', '.webp'];
  if (!allowedExtensions.some(ext => lowerPath.endsWith(ext))) {
    return new Response('Invalid file type', { 
      status: 400,
      headers: CORS_HEADERS,
    });
  }

  try {
    const object = await env.THUMBNAILS_BUCKET.get(filePath);
    
    if (!object) {
      return new Response('Thumbnail not found', { 
        status: 404,
        headers: CORS_HEADERS,
      });
    }

    const filename = filePath.split('/').pop() || 'thumbnail.jpg';
    const contentType = lowerPath.endsWith('.png') 
      ? 'image/png' 
      : lowerPath.endsWith('.webp')
      ? 'image/webp'
      : 'image/jpeg';
    
    const headers = new Headers(CORS_HEADERS);
    headers.set('Content-Type', contentType);
    headers.set('Content-Disposition', `inline; filename="${encodeURIComponent(filename)}"`);
    headers.set('Cache-Control', 'public, max-age=31536000, immutable');
    headers.set('X-Content-Type-Options', 'nosniff');

    return new Response(object.body, { headers });
  } catch (error) {
    console.error('Error serving thumbnail:', error);
    return new Response(
      JSON.stringify({ 
        error: 'Failed to serve thumbnail',
        message: error instanceof Error ? error.message : 'Unknown error'
      }),
      { 
        status: 500,
        headers: { ...CORS_HEADERS, 'Content-Type': 'application/json' },
      }
    );
  }
}

/**
 * Handle sitemap submission to Google Search Console
 */
async function handleSitemapSubmit(request: Request, env: Env): Promise<Response> {
  if (request.method === 'GET') {
    const siteUrl = env.SITE_URL || env.GOOGLE_SITE_URL || 'https://rockymountainvending.com';
    const sitemapUrl = `${siteUrl}/sitemap.xml`;
    
    return new Response(
      JSON.stringify({
        message: 'Google Search Console Sitemap Submission API',
        sitemapUrl,
        configured: !!(env.GOOGLE_SERVICE_ACCOUNT_EMAIL && env.GOOGLE_PRIVATE_KEY),
        instructions: 'POST to this endpoint with optional sitemapUrl and siteUrl in body',
      }),
      {
        headers: { ...CORS_HEADERS, 'Content-Type': 'application/json' },
      }
    );
  }

  if (request.method !== 'POST') {
    return new Response('Method not allowed', { 
      status: 405,
      headers: CORS_HEADERS,
    });
  }

  try {
    const body = await request.json() as { sitemapUrl?: string; siteUrl?: string };
    const siteUrl = body.siteUrl || env.SITE_URL || env.GOOGLE_SITE_URL || 'https://rockymountainvending.com';
    const sitemapUrl = body.sitemapUrl || `${siteUrl}/sitemap.xml`;

    if (!env.GOOGLE_SERVICE_ACCOUNT_EMAIL || !env.GOOGLE_PRIVATE_KEY) {
      return new Response(
        JSON.stringify({
          success: false,
          error: 'Google Search Console credentials not configured',
          message: 'Please set GOOGLE_SERVICE_ACCOUNT_EMAIL and GOOGLE_PRIVATE_KEY environment variables',
        }),
        { 
          status: 500,
          headers: { ...CORS_HEADERS, 'Content-Type': 'application/json' },
        }
      );
    }

    // Note: Full Google Search Console API integration would require googleapis library
    // For now, this is a placeholder that returns success
    // To implement fully, you would need to:
    // 1. Install googleapis in the worker (may require bundling)
    // 2. Use JWT authentication with service account
    // 3. Call searchconsole.sitemaps.submit()

    return new Response(
      JSON.stringify({
        success: true,
        message: 'Sitemap submission endpoint ready',
        sitemapUrl,
        siteUrl,
        note: 'Google Search Console API integration requires additional setup. See documentation.',
      }),
      {
        headers: { ...CORS_HEADERS, 'Content-Type': 'application/json' },
      }
    );
  } catch (error) {
    return new Response(
      JSON.stringify({
        success: false,
        error: error instanceof Error ? error.message : 'Unknown error occurred',
      }),
      { 
        status: 500,
        headers: { ...CORS_HEADERS, 'Content-Type': 'application/json' },
      }
    );
  }
}

/**
 * Handle URL indexing requests
 */
async function handleRequestIndexing(request: Request, env: Env): Promise<Response> {
  if (request.method === 'GET') {
    return new Response(
      JSON.stringify({
        message: 'Google Search Console URL Indexing Request API',
        configured: !!(env.GOOGLE_SERVICE_ACCOUNT_EMAIL && env.GOOGLE_PRIVATE_KEY),
        instructions: "POST to this endpoint with { url: 'https://example.com/page' } in body",
      }),
      {
        headers: { ...CORS_HEADERS, 'Content-Type': 'application/json' },
      }
    );
  }

  if (request.method !== 'POST') {
    return new Response('Method not allowed', { 
      status: 405,
      headers: CORS_HEADERS,
    });
  }

  try {
    const body = await request.json() as { url?: string };
    const { url } = body;

    if (!url) {
      return new Response(
        JSON.stringify({
          success: false,
          error: 'URL is required',
        }),
        { 
          status: 400,
          headers: { ...CORS_HEADERS, 'Content-Type': 'application/json' },
        }
      );
    }

    if (!env.GOOGLE_SERVICE_ACCOUNT_EMAIL || !env.GOOGLE_PRIVATE_KEY) {
      return new Response(
        JSON.stringify({
          success: false,
          error: 'Google Search Console credentials not configured',
          message: 'Please set GOOGLE_SERVICE_ACCOUNT_EMAIL and GOOGLE_PRIVATE_KEY environment variables',
        }),
        { 
          status: 500,
          headers: { ...CORS_HEADERS, 'Content-Type': 'application/json' },
        }
      );
    }

    // Note: Full Google Search Console API integration would require googleapis library
    // For now, this is a placeholder that returns success
    // To implement fully, you would need to:
    // 1. Install googleapis in the worker (may require bundling)
    // 2. Use JWT authentication with service account
    // 3. Call searchconsole.urlInspection.index.inspect()

    return new Response(
      JSON.stringify({
        success: true,
        message: 'Indexing request endpoint ready',
        url,
        note: 'Google Search Console API integration requires additional setup. See documentation.',
      }),
      {
        headers: { ...CORS_HEADERS, 'Content-Type': 'application/json' },
      }
    );
  } catch (error) {
    return new Response(
      JSON.stringify({
        success: false,
        error: error instanceof Error ? error.message : 'Unknown error occurred',
      }),
      { 
        status: 500,
        headers: { ...CORS_HEADERS, 'Content-Type': 'application/json' },
      }
    );
  }
}

/**
 * Health check endpoint
 */
function handleHealth(env: Env): Response {
  return new Response(
    JSON.stringify({
      status: 'ok',
      timestamp: new Date().toISOString(),
      buckets: {
        manuals: !!env.MANUALS_BUCKET,
        thumbnails: !!env.THUMBNAILS_BUCKET,
      },
    }),
    {
      headers: { ...CORS_HEADERS, 'Content-Type': 'application/json' },
    }
  );
}