feat(ViewModels, Views): 获取 liked tweets，在 Profile 页面展示

获取 liked tweets，在 Profile 页面展示

Signed-off-by: Ching <loooching@gmail.com>

dudu-tweet/dudu-tweet.xcodeproj/project.pbxproj

@@ -20,6 +20,7 @@
 		24A07CB82A02173400F4ECA8 /* FeedViewModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = 24A07CB72A02173400F4ECA8 /* FeedViewModel.swift */; };
 		24A07CBA2A02186500F4ECA8 /* Tweet.swift in Sources */ = {isa = PBXBuildFile; fileRef = 24A07CB92A02186500F4ECA8 /* Tweet.swift */; };
 		24A07CBC2A022B2000F4ECA8 /* ProfileViewModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = 24A07CBB2A022B2000F4ECA8 /* ProfileViewModel.swift */; };
+		24A07CC22A02302700F4ECA8 /* TweetRowViewModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = 24A07CC12A02302700F4ECA8 /* TweetRowViewModel.swift */; };
 		24A59AB42A002EB8009C9E3E /* MainTabView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 24A59AB32A002EB8009C9E3E /* MainTabView.swift */; };
 		24A59ABA2A0030CB009C9E3E /* ExploreView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 24A59AB92A0030CB009C9E3E /* ExploreView.swift */; };
 		24A59ABC2A0030EC009C9E3E /* NotificationsView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 24A59ABB2A0030EC009C9E3E /* NotificationsView.swift */; };
@@ -68,6 +69,7 @@
 		24A07CB72A02173400F4ECA8 /* FeedViewModel.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = FeedViewModel.swift; sourceTree = "<group>"; };
 		24A07CB92A02186500F4ECA8 /* Tweet.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Tweet.swift; sourceTree = "<group>"; };
 		24A07CBB2A022B2000F4ECA8 /* ProfileViewModel.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ProfileViewModel.swift; sourceTree = "<group>"; };
+		24A07CC12A02302700F4ECA8 /* TweetRowViewModel.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = TweetRowViewModel.swift; sourceTree = "<group>"; };
 		24A59AB32A002EB8009C9E3E /* MainTabView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MainTabView.swift; sourceTree = "<group>"; };
 		24A59AB92A0030CB009C9E3E /* ExploreView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ExploreView.swift; sourceTree = "<group>"; };
 		24A59ABB2A0030EC009C9E3E /* NotificationsView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = NotificationsView.swift; sourceTree = "<group>"; };
@@ -238,11 +240,28 @@
 		2492CC262A0025A50086C525 /* Tweets */ = {
 			isa = PBXGroup;
 			children = (
-				2492CC272A0025DD0086C525 /* TweetRowView.swift */,
+				24A07CBE2A022FCB00F4ECA8 /* ViewModels */,
+				24A07CBD2A022FC600F4ECA8 /* Views */,
 			);
 			path = Tweets;
 			sourceTree = "<group>";
 		};
+		24A07CBD2A022FC600F4ECA8 /* Views */ = {
+			isa = PBXGroup;
+			children = (
+				2492CC272A0025DD0086C525 /* TweetRowView.swift */,
+			);
+			path = Views;
+			sourceTree = "<group>";
+		};
+		24A07CBE2A022FCB00F4ECA8 /* ViewModels */ = {
+			isa = PBXGroup;
+			children = (
+				24A07CC12A02302700F4ECA8 /* TweetRowViewModel.swift */,
+			);
+			path = ViewModels;
+			sourceTree = "<group>";
+		};
 		24A59AB22A002E79009C9E3E /* MainTab */ = {
 			isa = PBXGroup;
 			children = (
@@ -522,6 +541,7 @@
 				24A59ABA2A0030CB009C9E3E /* ExploreView.swift in Sources */,
 				24A07CB62A020FF900F4ECA8 /* UploadTweetViewModel.swift in Sources */,
 				24A07CB42A020ECB00F4ECA8 /* TweetService.swift in Sources */,
+				24A07CC22A02302700F4ECA8 /* TweetRowViewModel.swift in Sources */,
 				24A59AD22A00BE14009C9E3E /* SideMenuViewModel.swift in Sources */,
 				24A59ADF2A00DCC2009C9E3E /* TextArea.swift in Sources */,
 				24A07CB22A01869F00F4ECA8 /* SearchBar.swift in Sources */,

dudu-tweet/dudu-tweet/Core/Components/Tweets/ViewModels/TweetRowViewModel.swift

@@ -0,0 +1,38 @@
+//
+//  TweetRowViewModel.swift
+//  dudu-tweet
+//
+//  Created by ching on 2023/5/3.
+//
+
+import Foundation
+
+class TweetVeiwModel: ObservableObject {
+    private let service = TweetService()
+    @Published var tweet: Tweet
+
+    init(tweet: Tweet) {
+        self.tweet = tweet
+        self.checkUserLikedTweet()
+    }
+    
+    func likeTweet() {
+        service.likeTweet(tweet) { _ in
+            self.tweet.didLike = true
+        }
+    }
+    
+    func unlikeTweet() {
+        service.unlikeTweet(tweet) { _ in
+            self.tweet.didLike = false
+        }
+    }
+    
+    func checkUserLikedTweet() {
+        service.checkIfUserLikedTweet(tweet) { didLiked in
+            if didLiked {
+                self.tweet.didLike = true
+            }
+        }
+    }
+}

dudu-tweet/dudu-tweet/Core/Components/Tweets/Views/TweetRowView.swift

@@ -9,15 +9,15 @@ import SwiftUI
 import Kingfisher
 
 struct TweetRowView: View {
-    let tweet: Tweet
+    @ObservedObject var viewModel: TweetVeiwModel
     
     init(tweet: Tweet) {
-        self.tweet = tweet
+        self.viewModel = TweetVeiwModel(tweet: tweet)
     }
     var body: some View {
         VStack(alignment: .leading) {
             // profile image + user info + tweet
-            if let user = tweet.user {
+            if let user = viewModel.tweet.user {
                 HStack(alignment: .top, spacing: 12) {
                     // profile image
                     KFImage(URL(string: user.profileImageUrl))
@@ -41,7 +41,7 @@ struct TweetRowView: View {
                         }
                         
                         // tweet caption
-                        Text(tweet.caption)
+                        Text(viewModel.tweet.caption)
                             .font(.subheadline)
                             .multilineTextAlignment(.leading)
                     }
@@ -64,10 +64,11 @@ struct TweetRowView: View {
                 }
                 Spacer()
                 Button {
-                    // action here
+                    viewModel.tweet.didLike ?? false ? viewModel.unlikeTweet() : viewModel.likeTweet()
                 } label: {
-                    Image(systemName: "heart")
+                    Image(systemName: viewModel.tweet.didLike ?? false ? "heart.fill" : "heart")
                         .font(.subheadline)
+                        .foregroundColor(viewModel.tweet.didLike ?? false ? .red : .gray)
                 }
                 Spacer()
                 Button {

dudu-tweet/dudu-tweet/Core/Profile/ViewModels/ProfileViewModel.swift

@@ -10,12 +10,30 @@ import Foundation
 
 class ProfileViewModel: ObservableObject {
     @Published var tweets = [Tweet]()
+    @Published var likedTweets = [Tweet]()
     private let service = TweetService()
+    private let userService = UserService()
     let user: User
     
     init(user: User) {
         self.user = user
         self.fetchUserTweet()
+        self.fetchLikedTweets()
+    }
+    
+    var actionBarTitle: String {
+        user.isCurrentUser ? "Edit Profile" : "Follow"
+    }
+    
+    func tweets(forFilter filter: TweetFilterViewModel) -> [Tweet] {
+        switch filter {
+        case .tweets:
+            return tweets
+        case .replies:
+            return tweets
+        case .likes:
+            return likedTweets
+        }
     }
     
     func fetchUserTweet() {
@@ -27,4 +45,19 @@ class ProfileViewModel: ObservableObject {
             }
         }
     }
+    
+    func fetchLikedTweets() {
+        guard let uid = user.id else { return }
+        service.fetchLikedTweets(forUid: uid) { tweets in
+            self.likedTweets = tweets
+            
+            for i in 0 ..< tweets.count {
+                let uid = tweets[i].uid
+                self.userService.fetchUser(withUid: uid) { user in
+                    self.likedTweets[i].user = user
+                }
+            }
+
+        }
+    }
 }

dudu-tweet/dudu-tweet/Core/Profile/Views/ProfileView.swift

@@ -87,7 +87,7 @@ extension ProfileView {
             Button {
                 // action here
             } label: {
-                Text("Edit Profile")
+                Text(viewModel.actionBarTitle)
                     .font(.subheadline).bold()
                     .frame(width: 120, height: 32)
                     .foregroundColor(.black)
@@ -165,7 +165,7 @@ extension ProfileView {
     var tweetsView: some View {
         ScrollView {
             LazyVStack {
-                ForEach(viewModel.tweets) { tweet in
+                ForEach(viewModel.tweets(forFilter: self.selectedFilter)) { tweet in
                     TweetRowView(tweet: tweet)
                 }
             }

dudu-tweet/dudu-tweet/Model/Tweet.swift

@@ -16,4 +16,5 @@ struct Tweet: Identifiable, Decodable {
     var likes: Int
     
     var user: User?
+    var didLike: Bool? = false
 }

dudu-tweet/dudu-tweet/Model/User.swift

@@ -6,6 +6,7 @@
 //
 
 import FirebaseFirestoreSwift
+import Firebase
 
 struct User: Identifiable, Decodable {
     @DocumentID var id: String?
@@ -13,4 +14,6 @@ struct User: Identifiable, Decodable {
     let fullname: String
     let profileImageUrl: String
     let email: String
+    
+    var isCurrentUser: Bool { return Auth.auth().currentUser?.uid == self.id}
 }

dudu-tweet/dudu-tweet/Service/TweetService.swift

@@ -50,5 +50,64 @@ struct TweetService {
             completion(tweets.sorted(by: { $0.timestamp.dateValue() > $1.timestamp.dateValue()}))
         }
     }
+    
+    func likeTweet(_ tweet: Tweet, completion: @escaping(Bool) -> Void) {
+        guard let uid = Auth.auth().currentUser?.uid else { return }
+        guard let tweetId = tweet.id else { return }
+        
+        let userLikeRef = Firestore.firestore().collection("users").document(uid).collection("user-likes")
+        Firestore.firestore().collection("tweets").document(tweetId)
+            .updateData(["likes": tweet.likes + 1]) { _ in
+                userLikeRef.document(tweetId).setData([:]) { _ in
+                    completion(true)
+                }
+            }
+    }
+    
+    func unlikeTweet(_ tweet: Tweet, completion: @escaping(Bool) -> Void) {
+        guard let uid = Auth.auth().currentUser?.uid else { return }
+        guard let tweetId = tweet.id else { return }
+        guard tweet.likes > 0 else { return }
+        
+        let userLikeRef = Firestore.firestore().collection("users").document(uid).collection("user-likes")
+        Firestore.firestore().collection("tweets").document(tweetId)
+            .updateData(["likes": tweet.likes - 1]) { _ in
+                userLikeRef.document(tweetId).delete() { _ in
+                    completion(true)
+                }
+            }
+    }
+        
+    func checkIfUserLikedTweet(_ tweet: Tweet, completion: @escaping(Bool) -> Void) {
+        guard let uid = Auth.auth().currentUser?.uid else { return }
+        guard let tweetId = tweet.id else { return }
+        print("DEBUG: checking likes for \(tweetId)")
+        Firestore.firestore().collection("users").document(uid).collection("user-likes")
+            .document(tweetId)
+            .getDocument { snapshot, _ in
+                guard let snapshot = snapshot else { return }
+                completion(snapshot.exists)
+            }
+    }
+    
+    func fetchLikedTweets(forUid uid: String, completion: @escaping([Tweet]) -> Void) {
+        var tweets = [Tweet]()
+        Firestore.firestore().collection("users").document(uid).collection("user-likes")
+            .getDocuments { snapshot, _ in
+                guard let documents = snapshot?.documents else { return }
+                documents.forEach { doc in
+                    let tweetID = doc.documentID
+                    Firestore.firestore().collection("tweets")
+                        .document(tweetID)
+                        .getDocument { snapshot, _ in
+                            guard let tweet = try? snapshot?.data(as: Tweet.self) else { return }
+                            tweets.append(tweet)
+                            completion(tweets)
+                        }
+                }
+            }
+        
+    }
+    
 }