Merge pull request 'FIX/FEED_PAGINATION' (#62) from FIX/FEED_PAGINATION into master

Reviewed-on: #62

Sources/justMUSIC/lib/screens/feed_screen.dart

@@ -25,7 +25,7 @@ class _FeedScreenState extends State<FeedScreen> with SingleTickerProviderStateM
   late Animation<double> animation;
   late List<Post> friendFeed;
   Timer? timer;
-  var page = 0;
+  var pageFriend = 0;
   late List<Post> discoveryFeed;
   late Tuple2<List<Post>, List<Post>> displayFeed;
   bool isDismissed = true;
@@ -126,7 +126,7 @@ class _FeedScreenState extends State<FeedScreen> with SingleTickerProviderStateM
   @override
   Widget build(BuildContext context) {
     displayFeed =
-        Tuple2(MyApp.postViewModel.postsFriends.reversed.toList(), MyApp.postViewModel.bestPosts.reversed.toList());
+        Tuple2(MyApp.postViewModel.postsFriends.toList(), MyApp.postViewModel.bestPosts.toList());
     bool empty =
         (choiceFeed == true && displayFeed.item1.isEmpty) || (choiceFeed == false && displayFeed.item2.isEmpty);
     ScrollController _scrollController = ScrollController();
@@ -134,6 +134,15 @@ class _FeedScreenState extends State<FeedScreen> with SingleTickerProviderStateM
       if (_scrollController.position.maxScrollExtent ==
           _scrollController.position.pixels) {
         print("fin");
+        if (choiceFeed) {
+          setState(() {
+            MyApp.postViewModel.getMorePostsFriends();
+          });
+        } else {
+          setState(() {
+            MyApp.postViewModel.getMoreBestPosts();
+          });
+        }
       }
     });
 

Sources/justMUSIC/lib/services/PostService.dart

@@ -42,16 +42,41 @@ class PostService {
 
   deletePost() {}
 
-  Future<List<QueryDocumentSnapshot<Map<String, dynamic>>>> getPopularPosts(
+  Future<List<QueryDocumentSnapshot<Map<String, dynamic>>>> getPopularPosts(int limit) async {
-      {int limit = 10,
+    DateTime twentyFourHoursAgo = DateTime.now().subtract(Duration(hours: 24));
-      QueryDocumentSnapshot<Map<String, dynamic>>? offset}) async {
+    var response = await FirebaseFirestore.instance
+        .collection("posts")
+        .where("date", isGreaterThan: twentyFourHoursAgo)
+        .orderBy("date", descending: true)
+        .limit(limit)
+        .get();
+
+    MyApp.postViewModel.lastPostDiscovery = response.docs.isNotEmpty
+        ? response.docs.last
+        : MyApp.postViewModel.lastPostDiscovery;
+
+    var filteredPosts = response.docs.where((doc) {
+      String user = doc["user_id"];
+      return user != MyApp.userViewModel.userCurrent.id;
+    }).toList();
+    return filteredPosts;
+  }
+
+  Future<List<QueryDocumentSnapshot<Map<String, dynamic>>>> getMorePopularPosts(int limit) async {
+    DateTime twentyFourHoursAgo = DateTime.now().subtract(Duration(hours: 24));
     QuerySnapshot<Map<String, dynamic>> response;
     response = await FirebaseFirestore.instance
         .collection("posts")
-        .orderBy("date")
+        .where("date", isGreaterThan: twentyFourHoursAgo)
+        .orderBy("date", descending: true)
         .limit(limit)
+        .startAfterDocument(MyApp.postViewModel.lastPostDiscovery)
         .get();
 
+    MyApp.postViewModel.lastPostDiscovery = response.docs.isNotEmpty
+        ? response.docs.last
+        : MyApp.postViewModel.lastPostDiscovery;
+
     var filteredPosts = response.docs.where((doc) {
       String user = doc["user_id"];
       return user != MyApp.userViewModel.userCurrent.id;
@@ -59,18 +84,41 @@ class PostService {
     return filteredPosts;
   }
 
-  Future<List<QueryDocumentSnapshot<Map<String, dynamic>>>> getPostsFriends(
+  Future<List<QueryDocumentSnapshot<Map<String, dynamic>>>> getPostsFriends(int limit) async {
-      {int limit = 10, int offset = 0}) async {
     var response = await FirebaseFirestore.instance
         .collection("posts")
         .where("user_id", whereIn: [
           MyApp.userViewModel.userCurrent.id,
           ...MyApp.userViewModel.userCurrent.followed
         ])
-        .orderBy("date")
+        .where("")
+        .orderBy("date", descending: true)
         .limit(limit)
         .get();
 
+    MyApp.postViewModel.lastPostFriend = response.docs.isNotEmpty
+        ? response.docs.last
+        : MyApp.postViewModel.lastPostFriend;
+
+    return response.docs;
+  }
+
+  Future<List<QueryDocumentSnapshot<Map<String, dynamic>>>> getMorePostsFriends(int limit) async {
+    var response = await FirebaseFirestore.instance
+        .collection("posts")
+        .where("user_id", whereIn: [
+          MyApp.userViewModel.userCurrent.id,
+          ...MyApp.userViewModel.userCurrent.followed
+        ])
+        .orderBy("date", descending: true)
+        .limit(limit)
+        .startAfterDocument(MyApp.postViewModel.lastPostFriend)
+        .get();
+
+    MyApp.postViewModel.lastPostFriend = response.docs.isNotEmpty
+        ? response.docs.last
+        : MyApp.postViewModel.lastPostFriend;
+
     return response.docs;
   }
 

Sources/justMUSIC/lib/view_model/PostViewModel.dart

@@ -11,6 +11,8 @@ import '../model/mapper/PostMapper.dart';
 class PostViewModel {
   List<Post> _postsFriends = [];
   List<Post> _bestPosts = [];
+  var lastPostFriend;
+  var lastPostDiscovery;
   final PostService _postService = PostService();
 
   // Constructor
@@ -26,10 +28,10 @@ class PostViewModel {
     await _postService.createPost(description, idMusic, image, location);
   }
 
-  Future<List<Post>> getPostsFriends() async {
+  Future<List<Post>> getPostsFriends({int limit = 10}) async {
     try {
       _postsFriends = [];
-      var responseData = await _postService.getPostsFriends();
+      var responseData = await _postService.getPostsFriends(limit);
       List<String> ids = [];
       var postsFutures = responseData.map((value) {
         ids.add(value.data()["song_id"]);
@@ -40,7 +42,7 @@ class PostViewModel {
       for (int i = 0; i < posts.length; i++) {
         posts[i].music = musics[i];
       }
-      _postsFriends = posts;
+      _postsFriends.addAll(posts);
       return _postsFriends;
     } catch (e) {
       print(e);
@@ -49,13 +51,29 @@ class PostViewModel {
     }
   }
 
-  List<Post> getMorePostsFriends() {
+  void getMorePostsFriends({int limit = 10}) async {
-    throw new Error();
+    try {
+      var responseData = await _postService.getMorePostsFriends(limit);
+      List<String> ids = [];
+      var postsFutures = responseData.map((value) {
+        ids.add(value.data()["song_id"]);
+        return PostMapper.toModel(value);
+      }).toList();
+      var posts = await Future.wait(postsFutures);
+      List<Music> musics = await MyApp.musicViewModel.getMusicsWithIds(ids);
+      for (int i = 0; i < posts.length; i++) {
+        posts[i].music = musics[i];
+      }
+      _postsFriends.addAll(posts);
+    } catch (e) {
+      print(e);
+    }
   }
 
-  Future<List<Post>> getBestPosts() async {
+  Future<List<Post>> getBestPosts({int limit = 10}) async {
     try {
-      var responseData = await _postService.getPopularPosts();
+      _bestPosts = [];
+      var responseData = await _postService.getPopularPosts(limit);
       List<String> ids = [];
       var postsFutures = responseData.map((value) async {
         ids.add(value.data()["song_id"]);
@@ -66,7 +84,7 @@ class PostViewModel {
       for (int i = 0; i < posts.length; i++) {
         posts[i].music = musics[i];
       }
-      _bestPosts = posts;
+      _bestPosts.addAll(posts);
       return _bestPosts;
     } catch (e) {
       print(e);
@@ -75,8 +93,23 @@ class PostViewModel {
     }
   }
 
-  List<Post> getMoreBestPosts() {
+  void getMoreBestPosts({int limit = 10}) async {
-    throw new Error();
+    try {
+      var responseData = await _postService.getMorePopularPosts(limit);
+      List<String> ids = [];
+      var postsFutures = responseData.map((value) async {
+        ids.add(value.data()["song_id"]);
+        return await PostMapper.toModel(value);
+      }).toList();
+      var posts = await Future.wait(postsFutures);
+      List<Music> musics = await MyApp.musicViewModel.getMusicsWithIds(ids);
+      for (int i = 0; i < posts.length; i++) {
+        posts[i].music = musics[i];
+      }
+      _bestPosts.addAll(posts);
+    } catch (e) {
+      print(e);
+    }
   }
 
   Future<List<bool>> recapSevenDays(String id) async {