✨ User cache

lib/providers/user_directory.dart

@@ -1,19 +1,36 @@
+import 'dart:convert';
+
+import 'package:drift/drift.dart';
 import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
+import 'package:surface/database/database.dart';
+import 'package:surface/providers/database.dart';
 import 'package:surface/providers/sn_network.dart';
 import 'package:surface/types/account.dart';
 
 class UserDirectoryProvider {
   late final SnNetworkProvider _sn;
+  late final DatabaseProvider _dt;
 
   UserDirectoryProvider(BuildContext context) {
     _sn = context.read<SnNetworkProvider>();
+    _dt = context.read<DatabaseProvider>();
   }
 
   final Map<String, int> _idCache = {};
   final Map<int, SnAccount> _cache = {};
 
+  Future<int> loadAccountCache({int max = 100}) async {
+    final out = await (_dt.db.snLocalAccount.select()..limit(max)).get();
+    for (final ele in out) {
+      _cache[ele.id] = ele.content;
+      _idCache[ele.name] = ele.id;
+    }
+    return out.length;
+  }
+
   Future<List<SnAccount?>> listAccount(Iterable<dynamic> id) async {
+    // In-memory cache
     final out = List<SnAccount?>.generate(id.length, (e) => null);
     final plannedQuery = <int>{};
     for (var idx = 0; idx < out.length; idx++) {
@@ -27,6 +44,23 @@ class UserDirectoryProvider {
         plannedQuery.add(item);
       }
     }
+    // On-disk cache
+    if (plannedQuery.isEmpty) return out;
+    final dbResp = await (_dt.db.snLocalAccount.select()
+          ..where((e) => e.id.isIn(plannedQuery))
+          ..limit(plannedQuery.length))
+        .get();
+    for (var idx = 0; idx < out.length; idx++) {
+      if (out[idx] != null) continue;
+      if (dbResp.length <= idx) {
+        break;
+      }
+      out[idx] = dbResp[idx].content;
+      _cache[dbResp[idx].id] = dbResp[idx].content;
+      _idCache[dbResp[idx].name] = dbResp[idx].id;
+      plannedQuery.remove(dbResp[idx].id);
+    }
+    // Remote server
     if (plannedQuery.isEmpty) return out;
     final resp = await _sn.client
         .get('/cgi/id/users', queryParameters: {'id': plannedQuery.join(',')});
@@ -43,17 +77,28 @@ class UserDirectoryProvider {
       _idCache[respDecoded[sideIdx].name] = respDecoded[sideIdx].id;
       sideIdx++;
     }
+    if (respDecoded.isNotEmpty) _saveToLocal(respDecoded);
     return out;
   }
 
   Future<SnAccount?> getAccount(dynamic id) async {
+    // In-memory cache
     if (id is String && _idCache.containsKey(id)) {
       id = _idCache[id];
     }
     if (_cache.containsKey(id)) {
       return _cache[id];
     }
-
+    // On-disk cache
+    final dbResp = await (_dt.db.snLocalAccount.select()
+          ..where((e) => e.id.equals(id)))
+        .getSingleOrNull();
+    if (dbResp != null) {
+      _cache[dbResp.id] = dbResp.content;
+      _idCache[dbResp.name] = dbResp.id;
+      return dbResp.content;
+    }
+    // Remote server
     try {
       final resp = await _sn.client.get('/cgi/id/users/$id');
       final account = SnAccount.fromJson(
@@ -61,16 +106,39 @@ class UserDirectoryProvider {
       );
       _cache[account.id] = account;
       if (id is String) _idCache[id] = account.id;
+      _saveToLocal([account]);
       return account;
     } catch (err) {
       return null;
     }
   }
 
-  SnAccount? getAccountFromCache(dynamic id) {
+  SnAccount? getFromCache(dynamic id) {
     if (id is String && _idCache.containsKey(id)) {
       id = _idCache[id];
     }
     return _cache[id];
   }
+
+  Future<void> _saveToLocal(Iterable<SnAccount> out) async {
+    // For better on conflict resolution
+    // And consider the method usually called with usually small amount of data
+    // Use for to insert each record instead of bulk insert
+    List<Future<int>> queries = out.map((ele) {
+      return _dt.db.snLocalAccount.insertOne(
+        SnLocalAccountCompanion.insert(
+          id: Value(ele.id),
+          name: ele.name,
+          content: ele,
+        ),
+        onConflict: DoUpdate(
+          (_) => SnLocalAccountCompanion.custom(
+            name: Constant(ele.name),
+            content: Constant(jsonEncode(ele.toJson())),
+          ),
+        ),
+      );
+    }).toList();
+    await Future.wait(queries);
+  }
 }