feat(content): 추천 전체보기를 연결한다

SodaLive/Sources/V2/Main/Content/Overview/ContentOverviewViewModel.swift

@@ -0,0 +1,118 @@
+import Foundation
+import Combine
+
+final class ContentOverviewViewModel: ObservableObject {
+    private let repository = ContentOverviewRepository()
+    private var subscription = Set<AnyCancellable>()
+    private let pageSize = 20
+    private var latestRequestId = 0
+
+    let type: ContentOverviewType
+
+    @Published var items = [ContentOverviewItemResponse]()
+    @Published var page = 0
+    @Published var size = 20
+    @Published var hasNext = false
+    @Published var hasLoaded = false
+    @Published var isLoading = false
+    @Published var isLoadingNextPage = false
+    @Published var errorMessage = ""
+    @Published var isShowPopup = false
+
+    var shouldShowEmptyState: Bool {
+        hasLoaded && !isLoading && items.isEmpty
+    }
+
+    init(type: ContentOverviewType = .newAndHotAudio) {
+        self.type = type
+    }
+
+    func fetchFirstPageIfNeeded() {
+        guard !hasLoaded else { return }
+        fetchFirstPage()
+    }
+
+    func fetchFirstPage() {
+        fetchContents(page: 0, isNextPage: false)
+    }
+
+    func fetchNextPageIfNeeded(currentItem: ContentOverviewItemResponse) {
+        guard items.last?.contentId == currentItem.contentId else { return }
+        fetchNextPageIfPossible()
+    }
+
+    private func fetchNextPageIfPossible() {
+        guard hasNext, isLoading == false, isLoadingNextPage == false else { return }
+        fetchContents(page: page + 1, isNextPage: true)
+    }
+
+    private func fetchContents(page requestPage: Int, isNextPage: Bool) {
+        latestRequestId += 1
+        let requestId = latestRequestId
+
+        if isNextPage {
+            isLoadingNextPage = true
+        } else {
+            isLoading = true
+        }
+
+        repository.getContents(type: type, page: requestPage, size: pageSize)
+            .sink { [weak self] result in
+                guard let self else { return }
+                guard requestId == self.latestRequestId else { return }
+
+                switch result {
+                case .finished:
+                    DEBUG_LOG("finish")
+                case .failure(let error):
+                    ERROR_LOG(error.localizedDescription)
+                    self.applyFailureState()
+                }
+            } receiveValue: { [weak self] response in
+                guard let self else { return }
+                guard requestId == self.latestRequestId else { return }
+
+                do {
+                    let jsonDecoder = JSONDecoder()
+                    let decoded = try jsonDecoder.decode(ApiResponse<ContentOverviewPageResponse>.self, from: response.data)
+
+                    if let data = decoded.data, decoded.success {
+                        self.applySuccessState(data, isNextPage: isNextPage)
+                    } else {
+                        self.errorMessage = decoded.message ?? I18n.MainContentAll.loadFailedMessage
+                        self.isShowPopup = true
+                    }
+                } catch {
+                    ERROR_LOG(error.localizedDescription)
+                    self.errorMessage = I18n.MainContentAll.loadFailedMessage
+                    self.isShowPopup = true
+                }
+
+                self.hasLoaded = true
+                self.isLoading = false
+                self.isLoadingNextPage = false
+            }
+            .store(in: &subscription)
+    }
+
+    private func applySuccessState(_ data: ContentOverviewPageResponse, isNextPage: Bool) {
+        page = data.page
+        size = data.size
+        hasNext = data.hasNext
+        errorMessage = ""
+
+        if isNextPage {
+            items.append(contentsOf: data.items)
+        } else {
+            items = data.items
+        }
+    }
+
+    private func applyFailureState() {
+        errorMessage = I18n.MainContentAll.loadFailedMessage
+        isShowPopup = true
+        hasLoaded = true
+        isLoading = false
+        isLoadingNextPage = false
+    }
+}