Add a very simple Debug screen

This will show all the debug messages, which include when a file is
being ignored and not loaded, and hopefully all the exceptions. So the
user should be able to better understand why a file has been ignored.

It's not an ideal solution, but it's a quick fix.

Fixes #122

assets/langs/en.yaml

@@ -18,3 +18,5 @@ settings:
   analytics: Analytics
   crashReports: Collect Anonymous Crash Reports
   usageStats: Collect Anonymous Usage Statistics
+  debug: Debug App
+  debugLog: Look under the hood

lib/app.dart

@@ -32,7 +32,7 @@ import 'setup/screens.dart';
 
 class JournalApp extends StatelessWidget {
   static Future main(SharedPreferences pref) async {
-    Log.init();
+    await Log.init();
 
     var appState = AppState(pref);
     appState.dumpToLog();

lib/screens/debug_screen.dart

@@ -0,0 +1,55 @@
+import 'package:flutter/material.dart';
+import 'package:easy_localization/easy_localization.dart';
+import 'package:gitjournal/utils/logger.dart';
+
+class DebugScreen extends StatefulWidget {
+  @override
+  _DebugScreenState createState() => _DebugScreenState();
+}
+
+class _DebugScreenState extends State<DebugScreen> {
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: Text(tr('settings.debug')),
+        leading: IconButton(
+          icon: const Icon(Icons.arrow_back),
+          onPressed: () {
+            Navigator.of(context).pop();
+          },
+        ),
+      ),
+      body: ListView(
+        children: <Widget>[
+          for (var msg in Log.fetchLogs()) _buildLogWidget(msg),
+        ],
+      ),
+    );
+  }
+
+  Widget _buildLogWidget(LogMessage msg) {
+    var textStyle = Theme.of(context).textTheme.subhead;
+    textStyle = textStyle.copyWith(color: _colorForLevel(msg.l));
+
+    var str = DateTime.fromMillisecondsSinceEpoch(msg.t).toIso8601String() +
+        ' ' +
+        msg.msg;
+
+    if (msg.ex != null) {
+      str += ' ' + msg.ex;
+    }
+    if (msg.stack != null) {
+      str += ' ' + msg.stack;
+    }
+    return Text(str, style: textStyle);
+  }
+
+  Color _colorForLevel(String l) {
+    switch (l) {
+      case 'e':
+        return Colors.red;
+    }
+    return Colors.black;
+  }
+}

lib/screens/settings_screen.dart

@@ -2,6 +2,7 @@ import 'package:flutter/material.dart';
 import 'package:easy_localization/easy_localization.dart';
 
 import 'package:gitjournal/core/notes_folder_fs.dart';
+import 'package:gitjournal/screens/debug_screen.dart';
 import 'package:gitjournal/screens/settings_editors.dart';
 import 'package:gitjournal/settings.dart';
 import 'package:gitjournal/state_container.dart';
@@ -226,6 +227,16 @@ class SettingsListState extends State<SettingsList> {
         },
       ),
       VersionNumberTile(),
+      ListTile(
+        title: Text(tr('settings.debug')),
+        subtitle: Text(tr('settings.debugLog')),
+        onTap: () {
+          var route = MaterialPageRoute(
+            builder: (context) => DebugScreen(),
+          );
+          Navigator.of(context).push(route);
+        },
+      ),
     ]);
   }
 }

lib/utils/logger.dart

@@ -2,6 +2,7 @@ import 'dart:convert';
 import 'dart:io';
 
 import 'package:fimber/fimber.dart';
+import 'package:meta/meta.dart';
 import 'package:flutter/foundation.dart' as foundation;
 import 'package:path_provider/path_provider.dart';
 import 'package:path/path.dart' as p;
@@ -10,7 +11,7 @@ class Log {
   static String logFolderPath;
   static RandomAccessFile logFile;
 
-  static void init() async {
+  static Future<void> init() async {
     if (foundation.kDebugMode) {
       Fimber.plantTree(DebugTree.elapsed(useColors: true));
     } else {
@@ -25,7 +26,7 @@ class Log {
       // Ignore if it already exists
     }
 
-    setLogCapture(true);
+    await setLogCapture(true);
   }
 
   static void v(String msg, {dynamic ex, StackTrace stacktrace}) {
@@ -59,20 +60,25 @@ class Log {
     dynamic ex,
     StackTrace stackTrace,
   ) {
-    if (logFile == null) return;
-    var map = <String, dynamic>{
-      't': DateTime.now().millisecondsSinceEpoch,
-      'l': level,
-      'msg': msg.replaceAll('\n', ' '),
-      if (ex != null) 'ex': ex.toString().replaceAll('\n', ' '),
-      if (stackTrace != null)
-        'stack': stackTrace.toString().replaceAll('\n', ' '),
-    };
-    var str = json.encode(map);
+    if (logFile == null) {
+      return;
+    }
+
+    var logMsg = LogMessage(
+      t: DateTime.now().millisecondsSinceEpoch,
+      l: level,
+      msg: msg.replaceAll('\n', ' '),
+      ex: ex != null ? ex.toString().replaceAll('\n', ' ') : null,
+      stack: stackTrace != null
+          ? stackTrace.toString().replaceAll('\n', ' ')
+          : null,
+    );
+
+    var str = json.encode(logMsg.toMap());
     logFile.writeStringSync(str + '\n');
   }
 
-  static void setLogCapture(bool state) async {
+  static Future<void> setLogCapture(bool state) async {
     if (state) {
       var today = DateTime.now().toString().substring(0, 10);
       var logFilePath = p.join(logFolderPath, '$today.jsonl');
@@ -85,4 +91,53 @@ class Log {
       logFile = null;
     }
   }
+
+  static Iterable<LogMessage> fetchLogs() sync* {
+    var today = DateTime.now().toString().substring(0, 10);
+    for (var msg in fetchLogsForDate(today)) {
+      yield msg;
+    }
+  }
+
+  static Iterable<LogMessage> fetchLogsForDate(String date) sync* {
+    var file = File(p.join(logFolderPath, '$date.jsonl'));
+    var str = file.readAsStringSync();
+    for (var line in LineSplitter.split(str)) {
+      yield LogMessage.fromMap(json.decode(line));
+    }
+  }
+}
+
+class LogMessage {
+  int t;
+  String l;
+  String msg;
+  String ex;
+  String stack;
+
+  LogMessage({
+    @required this.t,
+    @required this.l,
+    @required this.msg,
+    this.ex,
+    this.stack,
+  });
+
+  Map<String, dynamic> toMap() {
+    return <String, dynamic>{
+      't': t,
+      'l': l,
+      'msg': msg,
+      if (ex != null && ex.isNotEmpty) 'ex': ex,
+      if (stack != null && stack.isNotEmpty) 'stack': stack,
+    };
+  }
+
+  LogMessage.fromMap(Map<String, dynamic> map) {
+    t = map['t'];
+    l = map['l'];
+    msg = map['msg'];
+    ex = map['ex'];
+    stack = map['stack'];
+  }
 }