trying to add sqlite caching functionality to cache firebase data

lib/provider/api.dart

@@ -1,4 +1,6 @@
 import 'dart:convert';
+import 'dart:ffi';
+import 'package:cloud_firestore/cloud_firestore.dart';
 import 'package:fetchingapp/provider/database.dart';
 import 'package:http/http.dart' as http;
 import 'package:flutter/foundation.dart' show kIsWeb;
@@ -13,6 +15,36 @@ class ApiProvider {
     return _getFromDB();
   }
 
+  Future getDataForFirestore() async {
+    return readCache().then((value) async {
+      if (value.isNotEmpty) {
+        print('READING FROM DB, NUMBER OF ENTRIES: ${value.length}');
+        callFirestore();
+        print('called firestore');
+
+        return value;
+      } else {
+        return callFirestore();
+
+        // return _getFromApi();
+      }
+    });
+  }
+
+  Future callFirestore() async {
+    cleanDB();
+    print('fetching from network');
+    var data = await FirebaseFirestore.instance
+        .collection('flutter-caching')
+        .orderBy('name')
+        .get();
+    var array = data.docs.map((e) {
+      return {'name': e['name']};
+    }).toList();
+    await addBatchOfFirestore(list: array);
+    return array;
+  }
+
   Future _getFromDB() async {
     return readCache().then((value) {
       if (value.isNotEmpty) {

lib/provider/database.dart

@@ -14,8 +14,20 @@ Future<Database> cacheDatabase() async {
 //read data
 Future<List<Map>> readCache() async {
   final db = await cacheDatabase();
+  var cache = db.query('cache');
+  print('db entries: $cache');
 
-  return db.query('cache');
+  return cache;
+}
+
+Future addBatchOfFirestore({required List<Map<String, dynamic>> list}) async {
+  final db = await cacheDatabase();
+  final batch = db.batch();
+  for (var item in list) {
+    batch.insert('cache', item, conflictAlgorithm: ConflictAlgorithm.replace);
+  }
+  await batch.commit(noResult: true);
+  print('batch insert complete');
 }
 
 // add entry

lib/provider/sql_queries.dart

@@ -1,10 +1,16 @@
 class Queries {
+  // String createCacheTable = '''
+  //   CREATE TABLE IF NOT EXISTS cache (
+  //     id INTEGER PRIMARY KEY,
+  //     name TEXT,
+  //     email TEXT,
+  //     body TEXT
+  //     );
+  //     ''';
   String createCacheTable = '''
     CREATE TABLE IF NOT EXISTS cache (
       id INTEGER PRIMARY KEY,
-      name TEXT,
-      email TEXT,
-      body TEXT
+      name TEXT
       );
       ''';
   String dropCacheTable = 'DROP TABLE cache';

lib/screen/firestore_page.dart

@@ -1,4 +1,5 @@
 import 'package:cloud_firestore/cloud_firestore.dart';
+import 'package:fetchingapp/provider/database.dart';
 import 'package:flutter/material.dart';
 
 class FirestoreDataPage extends StatefulWidget {
@@ -12,6 +13,9 @@ class _FirestoreDataPageState extends State<FirestoreDataPage> {
   final textController = TextEditingController();
 
   void addEntry() {
+    if (textController.text == '') {
+      return;
+    }
     FirebaseFirestore.instance
         .collection('flutter-caching')
         .add({'name': textController.text});
@@ -37,12 +41,32 @@ class _FirestoreDataPageState extends State<FirestoreDataPage> {
                 if (!snapshot.hasData) {
                   return const Center(child: CircularProgressIndicator());
                 } else {
+                  print(snapshot.data!.docs.length);
+                  var data = snapshot.data!.docs.map((e) {
+                    return {'name': e['name']};
+                  }).toList();
+                  // cleanDB();
+                  addBatchOfFirestore(list: data);
+                  var db = readCache().then((value) {
+                    return value;
+                    // if (value.isNotEmpty) {
+                    //   // print('reading from db');
+                    //   // print('reading from db');
+                    //   // return Text('database has data');
+                    // }
+                    // print(value);
+                  });
+
+                  print('db: $db');
+                  // readCache();
+
+                  // print(data);
                   return ListView(
                     children: snapshot.data!.docs.map((e) {
                       return ListTile(
                         title: Text(e['name']),
                         trailing: IconButton(
-                          icon: Icon(Icons.delete),
+                          icon: const Icon(Icons.delete),
                           onPressed: () {
                             e.reference.delete();
                           },

lib/screen/firestore_page_future.dart

@@ -0,0 +1,124 @@
+import 'package:cloud_firestore/cloud_firestore.dart';
+import 'package:fetchingapp/provider/api.dart';
+import 'package:fetchingapp/provider/database.dart';
+import 'package:flutter/material.dart';
+
+class FutureFireStore extends StatefulWidget {
+  const FutureFireStore({Key? key}) : super(key: key);
+
+  @override
+  _FutureFireStoreState createState() => _FutureFireStoreState();
+}
+
+class _FutureFireStoreState extends State<FutureFireStore> {
+  final textController = TextEditingController();
+
+  void addEntry() {
+    // if (textController.text == '') {
+    //   return;
+    // }
+    FirebaseFirestore.instance
+        .collection('flutter-caching')
+        .add({'name': textController.text});
+    textController.clear();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: const Text('Firestore Data'),
+      ),
+      body: Column(
+        children: [
+          Expanded(
+              child: Center(
+            child: FutureBuilder(
+                future: ApiProvider().getDataForFirestore(),
+                builder: (context, snapshot) {
+                  if (!snapshot.hasData) {
+                    return const Center(child: CircularProgressIndicator());
+                  } else {
+                    // return Text(snapshot.data.toString());
+                    return ListView.builder(
+                        itemCount: (snapshot.data as dynamic).length,
+                        itemBuilder: (context, index) {
+                          final entry = (snapshot.data as dynamic)[index];
+                          return ListTile(
+                            title: Text(entry['name'].toString()),
+                            leading: Icon(Icons.plus_one),
+                          );
+                        });
+                  }
+                }),
+          )),
+          TextField(
+              controller: textController,
+              onEditingComplete: () {
+                addEntry();
+              },
+              decoration: InputDecoration(
+                  prefixIcon: const Icon(Icons.add_circle),
+                  labelText: "Input new value and click Save:",
+                  suffixIcon: IconButton(
+                    icon: const Icon(Icons.save),
+                    splashColor: Colors.blue,
+                    tooltip: "Post message",
+                    onPressed: () {
+                      FirebaseFirestore.instance
+                          .collection('flutter-caching')
+                          .add({'name': textController.text});
+                      textController.clear();
+                    },
+                  ))),
+        ],
+      ),
+    );
+  }
+}
+
+// StreamBuilder(
+//               stream: FirebaseFirestore.instance
+//                   .collection('flutter-caching')
+//                   .orderBy('name')
+//                   .snapshots(),
+//               builder: (context, AsyncSnapshot<QuerySnapshot> snapshot) {
+//                 if (!snapshot.hasData) {
+//                   return const Center(child: CircularProgressIndicator());
+//                 } else {
+//                   print(snapshot.data!.docs.length);
+//                   var data = snapshot.data!.docs.map((e) {
+//                     return {'name': e['name']};
+//                   }).toList();
+//                   // cleanDB();
+//                   addBatchOfFirestore(list: data);
+//                   var db = readCache().then((value) {
+//                     return value;
+//                     // if (value.isNotEmpty) {
+//                     //   // print('reading from db');
+//                     //   // print('reading from db');
+//                     //   // return Text('database has data');
+//                     // }
+//                     // print(value);
+//                   });
+
+//                   print('db: $db');
+//                   // readCache();
+
+//                   // print(data);
+//                   return ListView(
+//                     children: snapshot.data!.docs.map((e) {
+//                       return ListTile(
+//                         title: Text(e['name']),
+//                         trailing: IconButton(
+//                           icon: const Icon(Icons.delete),
+//                           onPressed: () {
+//                             e.reference.delete();
+//                           },
+//                         ),
+//                       );
+//                     }).toList(),
+//                   );
+//                 }
+//               },
+//             ),

lib/screen/home_page.dart

@@ -1,10 +1,10 @@
 import 'package:fetchingapp/provider/database.dart';
 import 'package:fetchingapp/provider/google_authentication.dart';
 import 'package:fetchingapp/screen/firestore_page.dart';
+import 'package:fetchingapp/screen/firestore_page_future.dart';
 import 'package:fetchingapp/screen/login_page.dart';
 import 'package:firebase_auth/firebase_auth.dart';
 import 'package:flutter/material.dart';
-import 'package:fetchingapp/screen/data_page.dart';
 
 class HomePage extends StatelessWidget {
   const HomePage(this.user, {Key? key}) : super(key: key);
@@ -40,7 +40,7 @@ class HomePage extends StatelessWidget {
               Navigator.push(
                 context,
                 MaterialPageRoute(
-                    builder: (context) => const FirestoreDataPage()),
+                    builder: (context) => const FutureFireStore()),
               );
             },
           ),

lib/screen/login_page.dart

@@ -41,7 +41,7 @@ class _LoginPageState extends State<LoginPage> {
 
   @override
   Widget build(BuildContext context) {
-    FirebaseService().signOutFromGoogle();
+    // FirebaseService().signOutFromGoogle();
     return Scaffold(
       appBar: AppBar(
         title: const Text('Login Screen'),