From ab133d0e4f9909a6b200f78a2d6818e1eb38d3e0 Mon Sep 17 00:00:00 2001
From: vikingowl <christian@nachtigall.dev>
Date: Sat, 2 Aug 2025 23:53:16 +0200
Subject: [PATCH] implemented infinite scrolling with load more functionality,
 pagination support, and expanded state handling for articles

---
 TODO.md                                 |  3 +-
 frontend/src/components/NewsFilters.vue |  2 +-
 frontend/src/components/NewsList.vue    | 88 ++++++++++++++++++++-----
 frontend/src/stores/useNews.ts          | 52 ++++++++++++++-
 4 files changed, 125 insertions(+), 20 deletions(-)

diff --git a/TODO.md b/TODO.md
index 348b559..aa9f575 100644
--- a/TODO.md
+++ b/TODO.md
@@ -26,7 +26,8 @@
 - [ ] Duplicate article detection - Avoid showing same story from multiple sources
 
 ## User Experience
-- [ ] Dark/light theme toggle
+- [x] Dark/light theme toggle
+- [x] Infinite scroll / load more functionality for articles
 - [ ] Customizable article layout - List view, card view, magazine style
 - [ ] Keyboard shortcuts - Navigate articles without mouse
 - [ ] Offline reading support - Cache articles for offline access
diff --git a/frontend/src/components/NewsFilters.vue b/frontend/src/components/NewsFilters.vue
index 505b83f..7f64861 100644
--- a/frontend/src/components/NewsFilters.vue
+++ b/frontend/src/components/NewsFilters.vue
@@ -290,7 +290,7 @@ const availableCountries = computed(() => {
   return Array.from(countries).sort();
 });
 
-const articleCount = computed(() => news.articles.length);
+const articleCount = computed(() => news.allArticles.length);
 
 // Date presets
 const datePresets: DatePreset[] = [
diff --git a/frontend/src/components/NewsList.vue b/frontend/src/components/NewsList.vue
index beb9f01..a471e9a 100644
--- a/frontend/src/components/NewsList.vue
+++ b/frontend/src/components/NewsList.vue
@@ -44,16 +44,19 @@
 
           <!-- Summary -->
           <p
-            class="text-sm sm:text-base text-gray-700 dark:text-gray-300 line-clamp-3 mb-4 leading-relaxed">
+            class="text-sm sm:text-base text-gray-700 dark:text-gray-300 line-clamp-5 leading-relaxed">
             {{ article.summary }}
           </p>
+        </div>
 
-          <!-- View Summary Button -->
+        <!-- Article Footer -->
+        <div
+          class="flex justify-between items-center gap-4 p-4 sm:p6">
           <button
             @click="openModal(article)"
-            class="inline-flex items-center text-sm font-medium text-green-600 hover:text-green-800 transition-colors mb-3"
+            class="flex-1 inline-flex items-center justify-center cursor-pointer px-4 py-2 text-sm font-medium rounded-lg bg-green-100 text-green-700 hover:bg-green-200 dark:bg-green-900/30 dark:text-green-400 dark:hover:bg-green-900/50 transition-colors"
           >
-            View full summary
+            Full summary
             <svg class="ml-1 w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
               <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2"
                     d="M15 12a3 3 0 11-6 0 3 3 0 016 0z"/>
@@ -61,30 +64,33 @@
                     d="M2.458 12C3.732 7.943 7.523 5 12 5c4.478 0 8.268 2.943 9.542 7-1.274 4.057-5.064 7-9.542 7-4.477 0-8.268-2.943-9.542-7z"/>
             </svg>
           </button>
-        </div>
 
-        <!-- Article Footer -->
-        <div class="px-4 sm:px-6 pb-4 sm:pb-6">
           <a
             :href="article.url"
             target="_blank"
             rel="noopener noreferrer"
-            class="inline-flex items-center text-sm font-medium text-green-600 hover:text-green-800 transition-colors"
+            class="flex-1 inline-flex items-center justify-center px-4 py-2 text-sm font-medium rounded-lg bg-green-100 text-green-700 hover:bg-green-200 dark:bg-green-900/30 dark:text-green-400 dark:hover:bg-green-900/50 transition-colors"
           >
-            Read full article
+            Full article
             <svg class="ml-1 w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
               <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2"
-                    d="M10 6H6a2 2 0 00-2 2v10a2 2 0 002 2h10a2 2 0 002-2v-4M14 4h6m0 0v6m0-6L10 14"/>
+                    d="M10 6H6a2 2 0 00-2 2v10a2 2 0 002-2v-4M14 4h6m0 0v6m0-6L10 14"/>
             </svg>
           </a>
         </div>
       </article>
     </div>
 
-    <!-- Load More Button (if you want to add pagination later) -->
-    <div v-if="news.articles.length > 0" class="text-center mt-8">
-      <p class="text-sm text-gray-500">
-        Showing {{ news.articles.length }} articles
+    <!-- Loading State & Load More Trigger -->
+    <div v-if="news.articles.length > 0" class="text-center mt-8" ref="loadMoreTrigger">
+      <p v-if="loading" class="text-sm text-gray-500">
+        Loading more articles...
+      </p>
+      <p v-else-if="!news.hasMore" class="text-sm text-gray-500">
+        No more articles to load
+      </p>
+      <p v-else class="text-sm text-gray-500">
+        Showing {{ news.articles.length }} of {{ news.allArticles.length }} articles
       </p>
     </div>
 
@@ -98,11 +104,63 @@
 </template>
 
 <script setup lang="ts">
-import {ref} from 'vue';
+import {ref, onMounted, onUnmounted, watch} from 'vue';
 import {useNews} from '../stores/useNews';
 import ArticleModal from './ArticleModal.vue';
 
 const news = useNews();
+const loading = ref(false);
+
+const loadMoreArticles = async () => {
+  if (loading.value || !news.hasMore) return;
+  loading.value = true;
+  try {
+    await news.loadMore();
+  } catch (error) {
+    console.error('Error loading more articles:', error);
+  } finally {
+    loading.value = false;
+  }
+};
+
+const observer = ref<IntersectionObserver | null>(null);
+const loadMoreTrigger = ref<HTMLElement | null>(null);
+
+onMounted(() => {
+  observer.value = new IntersectionObserver(
+    (entries) => {
+      if (entries[0].isIntersecting) {
+        loadMoreArticles();
+      }
+    },
+    {threshold: 0.5}
+  );
+
+  if (loadMoreTrigger.value) {
+    observer.value.observe(loadMoreTrigger.value);
+  }
+});
+
+onUnmounted(() => {
+  if (observer.value) {
+    observer.value.disconnect();
+  }
+});
+
+// Watch for changes to the loadMoreTrigger element
+watch(loadMoreTrigger, (newEl, oldEl) => {
+  if (observer.value) {
+    // Disconnect from old element if it exists
+    if (oldEl) {
+      observer.value.unobserve(oldEl);
+    }
+
+    // Observe new element if it exists
+    if (newEl) {
+      observer.value.observe(newEl);
+    }
+  }
+});
 
 // Modal state
 const isModalOpen = ref(false);
diff --git a/frontend/src/stores/useNews.ts b/frontend/src/stores/useNews.ts
index c6b9ae2..8d40628 100644
--- a/frontend/src/stores/useNews.ts
+++ b/frontend/src/stores/useNews.ts
@@ -12,7 +12,20 @@ export const useNews = defineStore('news', {
       created_at: number
     }[],
     lastSync: 0,
-    clientTimezone: Intl.DateTimeFormat().resolvedOptions().timeZone
+    clientTimezone: Intl.DateTimeFormat().resolvedOptions().timeZone,
+    page: 1,
+    pageSize: 12,
+    hasMore: true,
+    allArticles: [] as {
+      id: number,
+      title: string,
+      summary: string,
+      url: string,
+      published: number,
+      country: string,
+      created_at: number
+    }[],
+    currentFilters: {} as Record<string, string | boolean>
   }),
   actions: {
     async loadLastSync() {
@@ -38,7 +51,11 @@ export const useNews = defineStore('news', {
 
       if (res.ok) {
         const data = await res.json();
-        this.articles = data;
+        this.allArticles = data;
+        this.currentFilters = filters;
+        this.page = 1;
+        this.hasMore = data.length > this.pageSize;
+        this.articles = data.slice(0, this.pageSize);
         this.lastSync = Date.now();
       }
     },
@@ -61,7 +78,11 @@ export const useNews = defineStore('news', {
         }
 
         const data = await res.json();
-        this.articles = data;
+        this.allArticles = data;
+        this.currentFilters = filters;
+        this.page = 1;
+        this.hasMore = data.length > this.pageSize;
+        this.articles = data.slice(0, this.pageSize);
         return data;
       } catch (error) {
         console.error('Failed to get news:', error);
@@ -69,6 +90,31 @@ export const useNews = defineStore('news', {
       }
     },
 
+    async loadMore() {
+      if (!this.hasMore) return;
+
+      const nextPage = this.page + 1;
+      const startIndex = this.page * this.pageSize;
+      const endIndex = startIndex + this.pageSize;
+
+      const nextPageItems = this.allArticles.slice(startIndex, endIndex);
+
+      if (nextPageItems.length > 0) {
+        this.articles = [...this.articles, ...nextPageItems];
+        this.page = nextPage;
+        this.hasMore = endIndex < this.allArticles.length;
+      } else {
+        this.hasMore = false;
+      }
+    },
+
+    // Reset pagination state
+    resetPagination() {
+      this.page = 1;
+      this.hasMore = this.allArticles.length > this.pageSize;
+      this.articles = this.allArticles.slice(0, this.pageSize);
+    },
+
     // New convenience methods
     async getAllNews() {
       return this.getNews({ all_countries: 'true', all_dates: 'true' });