nav

src/api/StorageManager.js

@@ -2,6 +2,7 @@ import { requireArray, requireDefined, requireObject } from '../utils/apiShape';
 import { notifyError } from '../utils/notify';
 import { parseCategoryTreeResponse } from '../store/categorySlice';
 import { ApiClient } from './ApiClient';
+import articleAutomat from '../store/articleAutomat';
 
 /**
  * Stale-while-revalidate cache: readers keep the current promise; update()
@@ -102,6 +103,10 @@ export class StorageManager extends ApiClient {
     requireDefined(article.sku, 'article.sku');
     const key = String(article.sku);
     this.#articlesBySku.set(key, article);
+    
+    // Update automat as well
+    articleAutomat.actions.setArticle(article);
+    
     const watchers = this.#articleWatchers.get(key);
     if (watchers) {
       for (const onArticle of watchers) onArticle(article);
@@ -329,6 +334,10 @@ export class StorageManager extends ApiClient {
 
   #onArticleSignal = (event) => {
     const sku = event.type.slice('article-'.length);
+    
+    // Update automat on SSE article events
+    void articleAutomat.actions.loadArticle(sku).catch((err) => notifyError(err));
+    
     if (this.#articleWatchers.has(sku)) {
       void this.loadArticle(sku).catch((err) => notifyError(err));
     }

src/automats/index.js

@@ -1 +1,3 @@
 export * from './deliveryEditorAutomat';
+export { default as navigationAutomat } from './navigationAutomat';
+export { setLastDeliveryPath, setLastArticleSku, clearNavigation } from './navigationAutomat';

src/automats/navigationAutomat.js

@@ -0,0 +1,54 @@
+import { Automat } from 'react-automat';
+
+/**
+ * Navigation automat to store last visited delivery and article paths.
+ * Used to return users to their previous context when clicking main menu items.
+ * 
+ * State shape:
+ * {
+ *   lastDeliveryPath: string | null,  // Last visited delivery path (e.g., '/lieferung/19' or '/lieferung/neu')
+ *   lastArticleSku: string | null,   // Last visited article SKU
+ * }
+ */
+const initialState = {
+  lastDeliveryPath: null,
+  lastArticleSku: null,
+};
+
+const navigationAutomat = new Automat(
+  initialState,
+  {
+    /**
+     * Set the last visited delivery path.
+     * @param {string|null} path - Full path like '/lieferung/19' or '/lieferung/neu'
+     */
+    setLastDeliveryPath(path) {
+      navigationAutomat.setState({ lastDeliveryPath: path });
+    },
+
+    /**
+     * Set the last visited article SKU.
+     * @param {string|null} sku
+     */
+    setLastArticleSku(sku) {
+      navigationAutomat.setState({ lastArticleSku: sku });
+    },
+
+    /**
+     * Clear all navigation history.
+     */
+    clearNavigation() {
+      navigationAutomat.setState({
+        lastDeliveryPath: null,
+        lastArticleSku: null,
+      });
+    },
+  },
+  {
+    name: 'navigation',
+    persist: false,
+  }
+);
+
+export default navigationAutomat;
+export const { setLastDeliveryPath, setLastArticleSku, clearNavigation } = navigationAutomat.actions;

src/components/AppShell.jsx

@@ -11,13 +11,34 @@ import UserMenu from './UserMenu';
 import { NAV_ITEMS, SUB_NAV, resolveActiveNav, resolveActiveSub } from '../nav';
 import { artikelQueryPath } from '../pages/artikel/artikelQuery';
 import { defaultCategoryPath } from '../pages/artikel/categoryRoute';
+import { navigationAutomat } from '../automats';
 
 const SIDEBAR_WIDTH = 144;
 const SUB_NAV_WIDTH = 88;
 
 class AppSidebar extends PureComponent {
+  constructor(props) {
+    super(props);
+    this.state = {
+      lastDeliveryPath: navigationAutomat.state.lastDeliveryPath,
+      lastArticleSku: navigationAutomat.state.lastArticleSku,
+    };
+  }
+
+  componentDidMount() {
+    this.unsub = navigationAutomat.subscribe(this, (state) => ({
+      lastDeliveryPath: state.lastDeliveryPath,
+      lastArticleSku: state.lastArticleSku,
+    }));
+  }
+
+  componentWillUnmount() {
+    this.unsub?.();
+  }
+
   render() {
     const { activeNav, navigate } = this.props;
+    const { lastDeliveryPath, lastArticleSku } = this.state;
 
     return (
       <Box
@@ -45,7 +66,21 @@ class AppSidebar extends PureComponent {
                 selected={active}
                 onMouseDown={(e) => e.preventDefault()}
                 onClick={() => {
-                  navigate(path === '/artikel' ? artikelQueryPath() : path);
+                  if (path === '/artikel') {
+                    if (lastArticleSku) {
+                      navigate(`/artikel/${lastArticleSku}`);
+                    } else {
+                      navigate(artikelQueryPath());
+                    }
+                  } else if (path === '/lieferung') {
+                    if (lastDeliveryPath) {
+                      navigate(lastDeliveryPath);
+                    } else {
+                      navigate(path);
+                    }
+                  } else {
+                    navigate(path);
+                  }
                 }}
                 sx={(theme) => ({
                   borderRadius: 0,

src/components/article/ArticleView.jsx

@@ -6,6 +6,7 @@ import {
   buildCategoryPath,
   defaultCategoryPath,
 } from '../../pages/artikel/categoryRoute';
+import articleAutomat, { createArticleSelector } from '../../store/articleAutomat';
 
 import ArticleTileTab from './ArticleTileTab';
 import ArticlePhotoTile from './ArticlePhotoTile';
@@ -24,34 +25,52 @@ class ArticleView extends PureComponent {
 
   constructor(props, context) {
     super(props, context);
-    const { article, unwatch } = context.article.watch(
+    
-      props.sku,
+    const sku = props.sku;
-      (next) => {
+    const currentArticle = articleAutomat.state[sku] ?? null;
-        this.setState({ article: next });
+    
-      },
+    this.state = { article: currentArticle };
-    );
-    this.state = { article };
-    this.unwatchArticle = unwatch;
     this.handleArticleDeleted = this.handleArticleDeleted.bind(this);
-  }
     
-  componentDidUpdate(prevProps) {
+    if (!currentArticle) {
-    const { sku } = this.props;
+      articleAutomat.actions.loadArticle(sku).catch((err) => {
-
+        console.error('Failed to load article:', err);
-    if (prevProps.sku !== sku) {
+      });
-      this.unwatchArticle?.();
-      const { article: next, unwatch } = this.context.article.watch(
-        sku,
-        (updated) => this.setState({ article: updated }),
-      );
-      this.unwatchArticle = unwatch;
-      this.setState({ article: next });
     }
   }
 
+  componentDidMount() {
+    this.subscribeToArticle();
+  }
+
+  componentDidUpdate(prevProps) {
+    if (prevProps.sku !== this.props.sku) {
+      const currentArticle = articleAutomat.state[this.props.sku] ?? null;
+      this.setState({ article: currentArticle });
+      
+      if (!currentArticle) {
+        articleAutomat.actions.loadArticle(this.props.sku).catch((err) => {
+          console.error('Failed to load article:', err);
+        });
+      }
+      
+      this.subscribeToArticle();
+    }
+  }
+
+  subscribeToArticle() {
+    if (this.unsub) this.unsub();
+    const selector = createArticleSelector(this.props.sku);
+    this.unsub = articleAutomat.subscribe(this, (state) => ({
+      article: selector(state),
+    }));
+  }
+
   componentWillUnmount() {
-    this.unwatchArticle?.();
+    if (this.unsub) {
-    this.unwatchArticle = null;
+      this.unsub();
+      this.unsub = null;
+    }
   }
 
   handleArticleDeleted() {

src/pages/artikel/index.jsx

@@ -29,6 +29,7 @@ import {
 import { preserveSearchFocus } from './searchFocus';
 import { artikelDetailPath } from './articleRoute';
 import withSearchParams from './withSearchParams';
+import { setLastArticleSku } from '../../automats';
 
 const resultRowSx = {
   alignItems: 'center',
@@ -171,6 +172,7 @@ class ArtikelSearchPage extends Component {
   componentDidMount() {
     document.addEventListener('mousedown', preserveSearchFocus, true);
     window.addEventListener('resize', this.handleWindowResize);
+    setLastArticleSku(null);
 
     // Kick off initial search (empty input = show all products).
     const { input } = this.state;

src/pages/artikel/kategorien.jsx

@@ -53,6 +53,7 @@ import {
   enableTerminalCategory,
   disableTerminalCategory,
 } from '../../store/posterminalSlice';
+import { setLastArticleSku } from '../../automats';
 
 const gridSx = {
   display: 'grid',
@@ -72,6 +73,7 @@ class ArtikelKategorienPage extends Component {
   }
 
   componentDidMount() {
+    setLastArticleSku(null);
     this.ensureTreeLoaded();
     this.ensurePosterminalsLoaded();
     this.syncCategoryFromUrl();

src/pages/artikel/lager.jsx

@@ -1,6 +1,12 @@
+import { useEffect } from 'react';
 import Typography from '@mui/material/Typography';
+import { setLastArticleSku } from '../../automats';
 
 export default function ArtikelLagerPage() {
+  useEffect(() => {
+    setLastArticleSku(null);
+  }, []);
+
   return (
     <Typography color="text.secondary">Lager — Inhalt folgt.</Typography>
   );

src/pages/artikel/sku.jsx

@@ -2,6 +2,7 @@ import { Component } from 'react';
 import { StorageManagerContext } from '../../api/storageManagerContext';
 import { ArticleView } from '../../components/article';
 import withSkuRoute from './withSkuRoute';
+import { setLastArticleSku } from '../../automats';
 
 class ArtikelSkuPage extends Component {
   static contextType = StorageManagerContext;
@@ -17,11 +18,13 @@ class ArtikelSkuPage extends Component {
 
   componentDidMount() {
     this.installEscape();
+    setLastArticleSku(this.props.sku);
     if (!this.state.ready) void this.ensureArticle();
   }
 
   componentDidUpdate(prevProps) {
     if (prevProps.sku !== this.props.sku) {
+      setLastArticleSku(this.props.sku);
       const ready =
         this.context.getArticle(this.props.sku) != null &&
         this.context.getCategoryState() != null;

src/pages/lieferung/index.jsx

@@ -1,7 +1,12 @@
 import { PureComponent } from 'react';
 import { ManifestList } from '../../components/manifest';
+import { setLastDeliveryPath } from '../../automats';
 
 class LieferungListePage extends PureComponent {
+  componentDidMount() {
+    setLastDeliveryPath(null);
+  }
+
   render() {
     return <ManifestList kind="delivery" />;
   }

src/pages/lieferung/lieferanten.jsx

@@ -17,6 +17,7 @@ import { StorageManagerContext } from '../../api/storageManagerContext';
 import { requireDefined, requireObject } from '../../utils/apiShape';
 import { backendErrorFrom } from '../../utils/backendError';
 import { notifyError } from '../../utils/notify';
+import { setLastDeliveryPath } from '../../automats';
 
 function sortSuppliers(suppliers) {
   return [...suppliers].sort((a, b) =>
@@ -48,6 +49,7 @@ class LieferungLieferantenPage extends PureComponent {
   }
 
   componentDidMount() {
+    setLastDeliveryPath(null);
     this._cancelled = false;
     void this.loadSuppliers();
   }

src/pages/lieferung/neu.jsx

@@ -30,6 +30,7 @@ import { notifyError } from '../../utils/notify';
 import { generatePdfThumbnail } from '../../utils/pdfThumbnail';
 import { extractPdfText } from '../../utils/pdfText';
 import { getDeliveryEditorAutomat } from '../../automats/deliveryEditorAutomat';
+import { setLastDeliveryPath } from '../../automats';
 import { delivery as deliveryApi } from '../../api';
 
 class LieferungNeuPage extends PureComponent {
@@ -85,8 +86,10 @@ class LieferungNeuPage extends PureComponent {
     this.unsubscribe = this.automat.subscribe(this);
     this._cancelled = false;
     if (this.props.docId != null) {
+      setLastDeliveryPath(`/lieferung/${this.props.docId}`);
       void this.loadEdit();
     } else {
+      setLastDeliveryPath('/lieferung/neu');
       void this.loadPartiesOnly();
       if (this.props.initialDelivery) {
         this.automat.actions.setDelivery(this.props.initialDelivery);

src/store/articleAutomat.js

@@ -0,0 +1,124 @@
+import { Automat, fetchJson } from 'react-automat';
+import { article } from '../api/index';
+import { requireObject, requireDefined } from '../utils/apiShape';
+
+/**
+ * Article automat store.
+ * Registered as window.artikel via the name option.
+ * State shape: { [sku: string]: article | null }
+ * 
+ * Usage in PureComponent:
+ * ```jsx
+ * import articleAutomat, { createArticleSelector } from '../../store/articleAutomat';
+ * 
+ * class ArticleView extends PureComponent {
+ *   constructor(props) {
+ *     super(props);
+ *     const sku = props.sku;
+ *     const currentArticle = articleAutomat.state[sku] ?? null;
+ *     this.state = { article: currentArticle };
+ *     
+ *     if (!currentArticle) {
+ *       articleAutomat.actions.loadArticle(sku).catch(console.error);
+ *     }
+ *   }
+ * 
+ *   componentDidMount() {
+ *     this.subscribeToArticle();
+ *   }
+ * 
+ *   componentDidUpdate(prevProps) {
+ *     if (prevProps.sku !== this.props.sku) {
+ *       const currentArticle = articleAutomat.state[this.props.sku] ?? null;
+ *       this.setState({ article: currentArticle });
+ *       
+ *       if (!currentArticle) {
+ *         articleAutomat.actions.loadArticle(this.props.sku).catch(console.error);
+ *       }
+ *       
+ *       this.subscribeToArticle();
+ *     }
+ *   }
+ * 
+ *   subscribeToArticle() {
+ *     if (this.unsub) this.unsub();
+ *     const selector = createArticleSelector(this.props.sku);
+ *     this.unsub = articleAutomat.subscribe(this, (state) => ({
+ *       article: selector(state),
+ *     }));
+ *   }
+ * 
+ *   componentWillUnmount() {
+ *     if (this.unsub) {
+ *       this.unsub();
+ *       this.unsub = null;
+ *     }
+ *   }
+ * 
+ *   render() {
+ *     const { article } = this.state;
+ *     if (!article) return null;
+ *     return <div>{article.name}</div>;
+ *   }
+ * }
+ * ```
+ */
+const articleAutomat = new Automat(
+  {},
+  {
+    /**
+     * Load article by SKU and update the store.
+     * @param {string} sku
+     */
+    async loadArticle(sku) {
+      const res = await article.getBySku(sku);
+      requireObject(res, 'GET /api/article/:sku');
+      requireObject(res.article, 'article');
+      requireDefined(res.article.sku, 'article.sku');
+      
+      articleAutomat.setState({
+        [sku]: res.article,
+      });
+      
+      return res.article;
+    },
+
+    /**
+     * Update article state after a successful mutation.
+     * @param {object} article
+     */
+    setArticle(article) {
+      requireObject(article, 'article');
+      requireDefined(article.sku, 'article.sku');
+      
+      articleAutomat.setState({
+        [article.sku]: article,
+      });
+    },
+
+    /**
+     * Clear article from store (e.g., after deletion).
+     * @param {string} sku
+     */
+    clearArticle(sku) {
+      articleAutomat.setState({
+        [sku]: null,
+      });
+    },
+  },
+  {
+    name: 'artikel',
+  }
+);
+
+/**
+ * Create a selector function for a specific SKU.
+ * This avoids closure issues when the SKU changes.
+ * @param {string} sku - The article SKU
+ * @returns {(state: object) => object|null} Selector function
+ */
+export function createArticleSelector(sku) {
+  return (state) => state[sku] ?? null;
+}
+
+export default articleAutomat;