implemented transaction propagation via event bus

Signed-off-by: Stephan Richter <s.richter@srsoftware.de>

frontend/src/routes/accounting/account.svelte

@@ -1,6 +1,6 @@
 <script>
 	import { onMount } from 'svelte';
-	import { api, get } from '../../urls.svelte';
+	import { api, eventStream, get } from '../../urls.svelte';
 	import { error, yikes } from '../../warn.svelte';
 	import { t } from '../../translations.svelte';
 
@@ -9,6 +9,7 @@
 
 	let { id }       = $props();
 	let account      = $state(null);
+	let eventSource      = null;
 	let filter       = $state([]);
 	let transactions = $state([]);
 	let filtered     = $derived(transactions.filter(t => checker(t.tags,filter)));
@@ -27,7 +28,6 @@
 			if (!transaction.destination.id) sums[0] += transaction.amount;
 			if (!transaction.source.id)      sums[0] -= transaction.amount;
 		}
-		window.setTimeout(scrollToBottom,100);
 		return sums;
 	}
 
@@ -50,6 +50,34 @@
 		filter = filter.filter(x => x != tag.toLowerCase());
 	}
 
+    function handleCreateEvent(evt){
+        const event_data = JSON.parse(evt.data);
+        const new_transaction = event_data.transaction;
+        transactions.push(new_transaction);
+		window.setTimeout(scrollToBottom,100);
+    }
+
+    function handleEvent(evt,method){
+        let event_data = JSON.parse(evt.data);
+        console.log({method, event_data});
+    }
+
+	function handleDeleteEvent(evt){
+        handleEvent(evt,'delete');
+    }
+
+    function handleUpdateEvent(evt){
+        const event_data = JSON.parse(evt.data);
+        const updated_transaction = event_data.transaction;
+        for (var idx in transactions){
+            if (transactions[idx].id == updated_transaction.id) {
+                updated_transaction.tags = transactions[idx].tags;
+                transactions[idx] = updated_transaction;
+                break;
+            }
+        }
+    }
+
 	async function load(){
 		let url = api(`accounting/${id}`);
 		let res = await get(url);
@@ -59,11 +87,15 @@
 			transactions = json.transactions;
 			users        = json.user_list;
 			account      = json.account;
+			try {
+				eventSource = eventStream(handleCreateEvent,handleUpdateEvent,handleDeleteEvent);
+			} catch (ignored) {}
+			window.setTimeout(scrollToBottom,100);
 		} else error(res);
 	}
 
 	function onSave(){
-		load();
+		// load();
 	}
 
 	function scrollToBottom(){