Add article facets endpoint and integrate into frontend

web/backend/routes/articles.js

@@ -1,5 +1,5 @@
 import express from 'express';
-import { getNotifiedArticles } from '../services/mongodb.js';
+import { getNotifiedArticles, getArticleFacets } from '../services/mongodb.js';
 import { basicAuthMiddleware } from '../middlewares/auth.js';
 
 const router = express.Router();
@@ -43,6 +43,24 @@ router.get('/', basicAuthMiddleware, async (req, res) => {
   }
 });
 
+// Obtener facets (valores únicos) para filtros (requiere autenticación obligatoria)
+router.get('/facets', basicAuthMiddleware, async (req, res) => {
+  try {
+    // Obtener usuario autenticado (requerido)
+    const user = req.user;
+    const isAdmin = user.role === 'admin';
+    
+    // Si no es admin, solo mostrar facets de sus propios artículos
+    const usernameFilter = isAdmin ? null : user.username;
+    
+    const facets = await getArticleFacets(usernameFilter);
+    
+    res.json(facets);
+  } catch (error) {
+    res.status(500).json({ error: error.message });
+  }
+});
+
 // Buscar artículos en MongoDB (requiere autenticación obligatoria)
 router.get('/search', basicAuthMiddleware, async (req, res) => {
   try {

web/backend/services/mongodb.js

@@ -331,6 +331,78 @@ export async function getNotifiedArticles(filter = {}) {
   }
 }
 
+export async function getArticleFacets(usernameFilter = null) {
+  if (!db) {
+    return {
+      platforms: [],
+      usernames: [],
+      workers: []
+    };
+  }
+  
+  try {
+    const articlesCollection = db.collection('articles');
+    
+    // Construir query base
+    const query = {};
+    if (usernameFilter) {
+      // Si hay filtro de username, solo buscar artículos de ese usuario
+      query['user_info.username'] = usernameFilter;
+    }
+    
+    // Obtener todos los artículos que coincidan con el filtro
+    const articles = await articlesCollection.find(query).toArray();
+    
+    // Extraer valores únicos
+    const platformsSet = new Set();
+    const usernamesSet = new Set();
+    const workersSet = new Set();
+    
+    for (const article of articles) {
+      // Plataforma (campo directo del artículo)
+      if (article.platform) {
+        platformsSet.add(article.platform);
+      }
+      
+      // Username y worker_name (pueden estar en user_info o en campos directos para compatibilidad)
+      const userInfoList = article.user_info || [];
+      
+      if (userInfoList.length > 0) {
+        // Estructura nueva: usar user_info
+        for (const userInfo of userInfoList) {
+          if (userInfo.username) {
+            usernamesSet.add(userInfo.username);
+          }
+          if (userInfo.worker_name) {
+            workersSet.add(userInfo.worker_name);
+          }
+        }
+      } else {
+        // Estructura antigua: usar campos directos
+        if (article.username) {
+          usernamesSet.add(article.username);
+        }
+        if (article.worker_name) {
+          workersSet.add(article.worker_name);
+        }
+      }
+    }
+    
+    return {
+      platforms: Array.from(platformsSet).sort(),
+      usernames: Array.from(usernamesSet).sort(),
+      workers: Array.from(workersSet).sort()
+    };
+  } catch (error) {
+    console.error('Error obteniendo facets de artículos:', error.message);
+    return {
+      platforms: [],
+      usernames: [],
+      workers: []
+    };
+  }
+}
+
 export async function getFavorites(username = null) {
   if (!db) {
     return [];