Add ability to save entire event log to a json file

lib/screens/logviewer_screen.dart

@@ -1,7 +1,12 @@
 import 'dart:convert';
+import 'dart:io';
+import 'dart:typed_data';
 
+import 'package:file_picker/file_picker.dart';
 import 'package:flutter/material.dart';
+import 'package:flutter_file_dialog/flutter_file_dialog.dart';
 import 'package:logging/logging.dart';
+import 'package:path_provider/path_provider.dart';
 import 'package:provider/provider.dart';
 
 import '../controls/padding.dart';
@@ -10,7 +15,12 @@ import '../controls/standard_appbar.dart';
 import '../services/log_service.dart';
 import '../services/setting_service.dart';
 import '../utils/clipboard_utils.dart';
+import '../utils/dateutils.dart';
+import '../utils/json_printer.dart';
 import '../utils/logrecord_extensions.dart';
+import '../utils/snackbar_builder.dart';
+
+final _logger = Logger('LogViewerScreen');
 
 class LogViewerScreen extends StatefulWidget {
   const LogViewerScreen({super.key});
@@ -24,6 +34,49 @@ class _LogViewerScreenState extends State<LogViewerScreen> {
   var filterByText = false;
   var filterByModule = false;
   var filterModuleName = '';
+  var attemptingWrite = false;
+
+  Future<void> _writeEventsLog(List<LogRecord> events) async {
+    if (attemptingWrite) {
+      return;
+    }
+
+    attemptingWrite = true;
+    try {
+      final json =
+          PrettyJsonEncoder().convert(events.map((e) => e.toJson()).toList());
+      final filename = 'EventsLog_${DateTime.now().toFileNameString()}.json';
+      if (Platform.isAndroid || Platform.isIOS) {
+        final params = SaveFileDialogParams(
+          data: Uint8List.fromList(json.codeUnits),
+          fileName: filename,
+        );
+        await FlutterFileDialog.saveFile(params: params);
+        if (mounted) {
+          buildSnackbar(context, 'Wrote Events Log to: $filename');
+        }
+      } else {
+        final appsDir = await getApplicationDocumentsDirectory();
+        final location = await FilePicker.platform.saveFile(
+          dialogTitle: 'Save Events Log',
+          fileName: filename,
+          initialDirectory: appsDir.path,
+        );
+        if (location != null) {
+          await File(location).writeAsString(json);
+          if (mounted) {
+            buildSnackbar(context, 'Wrote Events Log to: $location');
+          }
+        }
+      }
+    } catch (e) {
+      _logger.severe('Error attempting to write out log: $e');
+      if (mounted) {
+        buildSnackbar(context, 'Error attempting to write out log: $e');
+      }
+    }
+    attemptingWrite = false;
+  }
 
   @override
   Widget build(BuildContext context) {
@@ -32,23 +85,28 @@ class _LogViewerScreenState extends State<LogViewerScreen> {
     final events = logService.events;
 
     return Scaffold(
-        appBar: StandardAppBar.build(context, 'Log Viewer'),
-        body: Center(
-          child: Padding(
-            padding: const EdgeInsets.all(8.0),
-            child: ResponsiveMaxWidth(
-              child: Column(
-                children: [
-                  buildLogPanel(settings),
-                  buildModuleFilter(settings, events),
-                  buildTextSearchPanel(),
-                  const VerticalPadding(),
-                  buildLogList(settings.logLevel, events),
-                ],
-              ),
+      appBar: StandardAppBar.build(context, 'Log Viewer'),
+      body: Center(
+        child: Padding(
+          padding: const EdgeInsets.all(8.0),
+          child: ResponsiveMaxWidth(
+            child: Column(
+              children: [
+                buildLogPanel(settings),
+                buildModuleFilter(settings, events),
+                buildTextSearchPanel(),
+                const VerticalPadding(),
+                buildLogList(settings.logLevel, events),
+              ],
             ),
           ),
-        ));
+        ),
+      ),
+      floatingActionButton: FloatingActionButton.small(
+        onPressed: () => _writeEventsLog(events),
+        child: const Icon(Icons.save),
+      ),
+    );
   }
 
   Widget buildLogPanel(SettingsService settings) {
@@ -78,7 +136,7 @@ class _LogViewerScreenState extends State<LogViewerScreen> {
           });
         },
       ),
-      title: const Text('Filter by module:'),
+      title: filterByModule ? null : const Text('Filter by module'),
       trailing: !filterByModule
           ? null
           : DropdownButton<String>(
@@ -105,6 +163,7 @@ class _LogViewerScreenState extends State<LogViewerScreen> {
         },
       ),
       title: TextField(
+        enabled: filterByText,
         onChanged: (value) {
           setState(() {
             filterText = value.toLowerCase();

lib/utils/dateutils.dart

@@ -58,3 +58,9 @@ class ElapsedDateUtils {
     return 'seconds ago';
   }
 }
+
+const _separator = '_';
+
+extension DateTimeExtensions on DateTime {
+  String toFileNameString() => '$year$month$day$_separator$hour$minute$second';
+}