WIP

Author: timunie

src/Avalonia.Samples/CompleteApps/AdvancedToDoList/AdvancedToDoList.Browser/Services/BrowserDatabaseService.cs

@@ -10,7 +10,7 @@ public partial class BrowserDbService : IDbService
     public string GetDatabasePath()
     {
         // This path must match the DB_FILENAME in storage.js
-        return "/todo.db";
+        return "todo.db";
     }
 
     public async Task SaveAsync()

src/Avalonia.Samples/CompleteApps/AdvancedToDoList/AdvancedToDoList.Browser/wwwroot/main.js

@@ -1,5 +1,5 @@
 import { dotnet } from './_framework/dotnet.js'
-import {loadSQLite} from "./storage.js";
+import {loadSQLite, idbGet, IDB_KEY} from "./storage.js";
 
 const is_browser = typeof window != "undefined";
 if (!is_browser) throw new Error(`Expected to be running in a browser`);
@@ -11,6 +11,26 @@ const dotnetRuntime = await dotnet
     .withApplicationArgumentsFromQuery()
     .create();
 
+// Expose runtime for storage synchronization
+window.dotnetRuntime = dotnetRuntime;
+
+// Restore database into .NET VFS if it exists in IndexedDB
+try {
+    const savedBytes = await idbGet(IDB_KEY);
+    if (savedBytes && savedBytes.byteLength > 0) {
+        console.log(`Restoring database to .NET VFS (${savedBytes.byteLength} bytes)...`);
+        // Try different ways to access FS as it might depend on the runtime version
+        const FS = (typeof dotnetRuntime.getModule === 'function' ? dotnetRuntime.getModule().FS : dotnetRuntime.Module?.FS) || dotnetRuntime.FS;
+        if (!FS) throw new Error("Could not find Emscripten FS in dotnetRuntime");
+        FS.writeFile('todo.db', savedBytes);
+        console.log('Database restored to .NET VFS.');
+    } else {
+        console.log('No saved database found in IndexedDB to restore to .NET VFS.');
+    }
+} catch (err) {
+    console.error('Failed to restore database to .NET VFS:', err);
+}
+
 const config = dotnetRuntime.getConfig();
 
 await dotnetRuntime.runMain(config.mainAssemblyName, [globalThis.location.href]);

src/Avalonia.Samples/CompleteApps/AdvancedToDoList/AdvancedToDoList.Browser/wwwroot/sqlite3-worker1.js

@@ -46,21 +46,26 @@
                    if (data && data.type === 'upload') {
                        const args = data.args;
                        try {
+                           console.log('Worker: Handling upload for', args.filename, 'data size:', args.deserialize?.byteLength);
                            // Use the internal capi to create the file in MEMFS
                            sqlite3.capi.sqlite3_js_posix_create_file(args.filename, args.deserialize);
+                           console.log('Worker: Upload successful for', args.filename);
                            globalThis.postMessage({
                                type: 'upload',
                                messageId: data.messageId,
                                result: { filename: args.filename }
                            });
                        } catch (e) {
+                           console.error('Worker: Upload failed for', args.filename, 'Error:', e.message);
                            globalThis.postMessage({
                                type: 'error',
                                messageId: data.messageId,
-                               error: e.message
+                               error: e.message,
+                               stack: e.stack
                            });
                        }
                    } else {
+                       // console.log('Worker: Delegating message to original handler:', data.type);
                        return oldOnMessage(ev);
                    }
                };

src/Avalonia.Samples/CompleteApps/AdvancedToDoList/AdvancedToDoList.Browser/wwwroot/storage.js

@@ -18,11 +18,11 @@ globalThis.saveDatabase = async () => {
 };
 
 // IndexedDB helpers
-const IDB_DB = 'avalonia-sqlite3';
-const IDB_STORE = 'dbfiles';
-const IDB_KEY = 'todo.db';
+export const IDB_DB = 'avalonia-sqlite3';
+export const IDB_STORE = 'dbfiles';
+export const IDB_KEY = 'todo.db';
 
-function idbOpen() {
+export function idbOpen() {
     return new Promise((resolve, reject) => {
         const req = indexedDB.open(IDB_DB, 1);
         req.onupgradeneeded = () => req.result.createObjectStore(IDB_STORE);
@@ -31,7 +31,7 @@ function idbOpen() {
     });
 }
 
-async function idbPut(key, uint8) {
+export async function idbPut(key, uint8) {
     const db = await idbOpen();
     return new Promise((resolve, reject) => {
         const tx = db.transaction(IDB_STORE, 'readwrite');
@@ -44,7 +44,7 @@ async function idbPut(key, uint8) {
     });
 }
 
-async function idbGet(key) {
+export async function idbGet(key) {
     const db = await idbOpen();
     return new Promise((resolve, reject) => {
         const tx = db.transaction(IDB_STORE, 'readonly');
@@ -112,36 +112,55 @@ export async function loadSQLite() {
     // Restore saved DB (if any) into worker FS
     try {
         const saved = await idbGet(IDB_KEY);
-        const DB_FILENAME = '/todo.db';
+        const DB_FILENAME = 'todo.db';
 
         if (saved && saved.byteLength > 0) {
             console.log('Found saved DB in IndexedDB (' + saved.byteLength + ' bytes) — restoring into worker...');
             // We use our custom 'upload' message to populate the worker's MEMFS
-            await callWorker({ 
+            const uploadResp = await callWorker({ 
                 type: 'upload', 
                 args: { filename: DB_FILENAME, deserialize: saved } 
             });
-            console.log('DB bytes uploaded to worker VFS.');
+            console.log('DB bytes uploaded to worker VFS:', uploadResp);
         } else {
             console.log('No prior DB found in IndexedDB — worker will start with an empty DB.');
         }
 
         // send 'open' message to worker
+        console.log('Sending open message for:', DB_FILENAME);
         const resp = await callWorker({ type: 'open', args: { filename: DB_FILENAME } });
         if (resp && resp.type === 'open') {
-            console.log('DB opened in worker VFS.');
+            console.log('DB opened in worker VFS:', resp);
         } else {
-            console.warn('Worker open response:', resp);
+            console.warn('Worker open response (unexpected type):', resp);
         }
     } catch (e) {
-        console.error('Error opening/restoring DB in worker:', e);
+        console.error('Error opening/restoring DB in worker. Full error object:', JSON.stringify(e, null, 2));
     }
 
     // Replace global saveDatabase with one that asks the worker to export the DB and then persists to IndexedDB
     globalThis.saveDatabase = async () => {
         try {
-            const DB_FILENAME = '/todo.db';
-            console.log('Saving DB: requesting export from worker...');
+            const DB_FILENAME = 'todo.db';
+            
+            // Priority: Try to save from the main thread's .NET VFS first
+            const runtime = globalThis.window?.dotnetRuntime;
+            const dotnetFS = runtime && ((typeof runtime.getModule === 'function' ? runtime.getModule().FS : runtime.Module?.FS) || runtime.FS);
+            if (dotnetFS) {
+                try {
+                    console.log('Saving DB: reading from .NET main thread VFS...');
+                    const data = dotnetFS.readFile(DB_FILENAME);
+                    if (data && data.byteLength > 0) {
+                        await idbPut(IDB_KEY, data);
+                        console.log('DB persisted from .NET VFS to IndexedDB (' + data.byteLength + ' bytes).');
+                        return;
+                    }
+                } catch (vfsErr) {
+                    console.warn('Failed to read DB from .NET VFS (might not be created yet):', vfsErr);
+                }
+            }
+
+            console.log('Saving DB: fallback to requesting export from worker...');
             // Ask the worker to export the DB bytes back to us
             const resp = await callWorker({ type: 'export', args: { filename: DB_FILENAME } });
             // Expect the worker to respond with an object containing result.byteArray: Uint8Array

src/Avalonia.Samples/CompleteApps/AdvancedToDoList/AdvancedToDoList/Helper/DataBaseHelper.cs

@@ -94,8 +94,6 @@ Color TEXT NULL
             }
         }
 
-        await UpdateIndexedDbAsync();
-        
         // If we have a connection, the DbService is known to be created. Thus, we can safely surpress the null warning here. 
         // For in memory DataSource, we cannot set the _init flag to true. 
         _initialized = App.DbService!.GetDatabasePath() != ":memory:";