feat(pwa): add web share target for text and images with offline queue

frontend/src/lib/shareTarget.ts

@@ -0,0 +1,117 @@
+export interface SharedData {
+  id?: number;
+  title?: string;
+  text?: string;
+  url?: string;
+  fileName?: string;
+  hasMedia?: boolean;
+  createdAt?: number;
+}
+
+const SHARE_DB_NAME = 'mindsift-share-target';
+const SHARE_STORE_NAME = 'shared_items';
+
+/**
+ * Combines title, text, url and media note into a single thought string.
+ * Ensures URLs are not duplicated if already present in the shared text or title.
+ */
+export function formatSharedThought(share: SharedData): string {
+  const title = (share.title || '').trim();
+  const text = (share.text || '').trim();
+  const url = (share.url || '').trim();
+  const mediaNote = '(Bild geteilt – Bilder im Posteingang werden noch nicht unterstützt)';
+
+  let content = '';
+
+  // Check if url is already contained in text or title
+  const urlInText = url !== '' && text.includes(url);
+  const urlInTitle = url !== '' && title.includes(url);
+
+  // Combine title and text
+  if (title && text) {
+    if (text === title) {
+      content = text;
+    } else if (text.startsWith(title)) {
+      content = text;
+    } else {
+      content = `${title}\n${text}`;
+    }
+  } else if (title) {
+    content = title;
+  } else if (text) {
+    content = text;
+  }
+
+  // Append URL if not already included in text or title
+  if (url && !urlInText && !urlInTitle) {
+    if (content) {
+      content = `${content}\n${url}`;
+    } else {
+      content = url;
+    }
+  }
+
+  // Media note handling
+  if (share.hasMedia || share.fileName) {
+    if (content) {
+      content = `${content}\n${mediaNote}`;
+    } else if (share.fileName) {
+      content = `[${share.fileName}] ${mediaNote}`;
+    } else {
+      content = mediaNote;
+    }
+  }
+
+  return content.trim();
+}
+
+/**
+ * Retrieves and removes all pending shared items stored in IndexedDB by the Service Worker.
+ */
+export async function consumePendingShares(): Promise<SharedData[]> {
+  if (typeof indexedDB === 'undefined') return [];
+
+  return new Promise((resolve) => {
+    try {
+      const req = indexedDB.open(SHARE_DB_NAME, 1);
+      req.onupgradeneeded = () => {
+        const db = req.result;
+        if (!db.objectStoreNames.contains(SHARE_STORE_NAME)) {
+          db.createObjectStore(SHARE_STORE_NAME, { autoIncrement: true, keyPath: 'id' });
+        }
+      };
+      req.onsuccess = () => {
+        const db = req.result;
+        if (!db.objectStoreNames.contains(SHARE_STORE_NAME)) {
+          db.close();
+          return resolve([]);
+        }
+
+        const tx = db.transaction(SHARE_STORE_NAME, 'readwrite');
+        const store = tx.objectStore(SHARE_STORE_NAME);
+        const getAllReq = store.getAll();
+
+        getAllReq.onsuccess = () => {
+          const items: SharedData[] = getAllReq.result || [];
+          store.clear();
+          tx.oncomplete = () => {
+            db.close();
+            resolve(items);
+          };
+          tx.onerror = () => {
+            db.close();
+            resolve(items);
+          };
+        };
+
+        getAllReq.onerror = () => {
+          db.close();
+          resolve([]);
+        };
+      };
+      req.onerror = () => resolve([]);
+    } catch {
+      resolve([]);
+    }
+  });
+}