feat: implement fetching all favorites in FavoriteSerivce, sort by offset

Author: makinosp

Sources/VRCKit/Services/FavoriteService.swift

@@ -27,7 +27,7 @@ public final actor FavoriteService: APIService, FavoriteServiceProtocol {
         try await withThrowingTaskGroup(of: [Favorite].self) { taskGroup in
             for offset in [0, 100, 200, 300] {
                 taskGroup.addTask { [unowned self] in
-                    try await self.listFavorites(n: 100, offset: offset, type: type)
+                    try await listFavorites(n: 100, offset: offset, type: type)
                 }
             }
             var results: [Favorite] = []

Sources/VRCKit/Services/WorldService.swift

@@ -13,22 +13,28 @@ public final actor WorldService: APIService, WorldServiceProtocol {
     public let client: APIClient
     private let path = "worlds"
     private let limit = 100
+    private let maxCount = 400
+    private typealias FavoriteWorldsWithOffset = (offset: Int, worlds: [FavoriteWorld])
 
     public func fetchWorld(worldId: String) async throws -> World {
         let response = try await client.request(path: "\(path)/\(worldId)", method: .get)
         return try await Serializer.shared.decode(response.data)
     }
 
     public func fetchFavoritedWorlds() async throws -> [FavoriteWorld] {
-        var allFavorites = Set<FavoriteWorld>()
-        var offset = 0
-        while true {
-            let batch = try await fetchFavoritedWorlds(n: limit, offset: offset)
-            allFavorites.formUnion(batch)
-            if batch.count < limit { break }
-            offset += limit
+        try await withThrowingTaskGroup(of: FavoriteWorldsWithOffset.self) { taskGroup in
+            for offset in Array(stride(from: 0, to: maxCount, by: limit)) {
+                taskGroup.addTask { [unowned self] in
+                    let worlds = try await fetchFavoritedWorlds(n: limit, offset: offset)
+                    return (offset, worlds)
+                }
+            }
+            var resultsDict: [FavoriteWorldsWithOffset] = []
+            for try await result in taskGroup { resultsDict.append(result) }
+            return resultsDict
+                .sorted { $0.offset < $1.offset }
+                .flatMap { $0.worlds }
         }
-        return Array(allFavorites)
     }
 
     private func fetchFavoritedWorlds(n: Int, offset: Int) async throws -> [FavoriteWorld] {