Rewrote lots of bad "async" code

Code that should've been fully async that was not previously actually async, such as the networking code, is now actually async. This makes it much easier to read and means that it makes a lot more sense in the context of the program. This also means that all uses of DispatchQueue.main.sync{} and DispatchQueue.main.async{} are now gone.
DetailView's fetching code benefitted the most from these changes, and is now just one iterative function instead of two cursed functions involving callbacks. As a result, you can now also pull down on the detail view to refresh the data, which is handy. Note that occupancy isn't updated when doing this currently due to a task issue I haven't figured out yet, but you can just go back out and in to update that anyway.
ContentView will also now automatically refresh the data if the last refreshed date is no longer today, so if you let the app sit in the background and then focus it, dates should automatically update to being for today.

RIT Dining.xcodeproj/project.pbxproj

@@ -257,7 +257,7 @@
 				ASSETCATALOG_COMPILER_GLOBAL_ACCENT_COLOR_NAME = AccentColor;
 				CODE_SIGN_IDENTITY = "Apple Development";
 				CODE_SIGN_STYLE = Automatic;
-				CURRENT_PROJECT_VERSION = 12;
+				CURRENT_PROJECT_VERSION = 13;
 				DEVELOPMENT_TEAM = 5GF7GKNTK4;
 				ENABLE_PREVIEWS = YES;
 				GENERATE_INFOPLIST_FILE = YES;
@@ -291,7 +291,7 @@
 				ASSETCATALOG_COMPILER_GLOBAL_ACCENT_COLOR_NAME = AccentColor;
 				CODE_SIGN_IDENTITY = "Apple Development";
 				CODE_SIGN_STYLE = Automatic;
-				CURRENT_PROJECT_VERSION = 12;
+				CURRENT_PROJECT_VERSION = 13;
 				DEVELOPMENT_TEAM = 5GF7GKNTK4;
 				ENABLE_PREVIEWS = YES;
 				GENERATE_INFOPLIST_FILE = YES;

RIT Dining/ContentView.swift

@@ -7,6 +7,71 @@
 
 import SwiftUI
 
+// This view handles the actual location list, because having it inside ContentView was too complex (both visually and for the
+// type checker too, apparently).
+struct LocationList: View {
+    @State var filteredLocations: [DiningLocation]
+    @Environment(Favorites.self) var favorites
+    
+    var body: some View {
+        ForEach($filteredLocations) { $location in
+            NavigationLink(destination: DetailView(location: $location)) {
+                VStack(alignment: .leading) {
+                    HStack {
+                        Text(location.name)
+                        if favorites.contains(location) {
+                            Image(systemName: "star.fill")
+                                .foregroundStyle(.yellow)
+                        }
+                    }
+                    switch location.open {
+                    case .open:
+                        Text("Open")
+                            .foregroundStyle(.green)
+                    case .closed:
+                        Text("Closed")
+                            .foregroundStyle(.red)
+                    case .openingSoon:
+                        Text("Opening Soon")
+                            .foregroundStyle(.orange)
+                    case .closingSoon:
+                        Text("Closing Soon")
+                            .foregroundStyle(.orange)
+                    }
+                    if let times = location.diningTimes, !times.isEmpty {
+                        ForEach(times, id: \.self) { time in
+                            Text("\(dateDisplay.string(from: time.openTime)) - \(dateDisplay.string(from: time.closeTime))")
+                                .foregroundStyle(.secondary)
+                        }
+                    } else {
+                        Text("Not Open Today")
+                            .foregroundStyle(.secondary)
+                    }
+                }
+            }
+            .swipeActions {
+                Button(action: {
+                    withAnimation {
+                        if favorites.contains(location) {
+                            favorites.remove(location)
+                        } else {
+                            favorites.add(location)
+                        }
+                    }
+                    
+                }) {
+                    if favorites.contains(location) {
+                        Label("Unfavorite", systemImage: "star")
+                    } else {
+                        Label("Favorite", systemImage: "star")
+                    }
+                }
+                .tint(favorites.contains(location) ? .yellow : nil)
+            }
+        }
+    }
+}
+
 struct ContentView: View {
     // Save sort/filter options in AppStorage so that they actually get saved.
     @AppStorage("openLocationsOnly") var openLocationsOnly: Bool = false
@@ -29,8 +94,7 @@ struct ContentView: View {
     // Asynchronously fetch the data for all of the locations and parse their data to display it.
     private func getDiningData() async {
         var newDiningLocations: [DiningLocation] = []
-        getAllDiningInfo(date: nil) { result in
+        switch await getAllDiningInfo(date: nil) {
-            switch result {
         case .success(let locations):
             for i in 0..<locations.locations.count {
                 let diningInfo = parseLocationInfo(location: locations.locations[i], forDate: nil)
@@ -44,7 +108,6 @@ struct ContentView: View {
             loadFailed = true
         }
     }
-    }
     
     // Start a perpetually running timer to refresh the open statuses, so that they automatically switch as appropriate without
     // needing to refresh the data. You don't need to yell at the API again to know that the location opening at 11:00 AM should now
@@ -54,6 +117,13 @@ struct ContentView: View {
             for location in diningLocations.indices {
                 diningLocations[location].updateOpenStatus()
             }
+            // If the last refreshed date isn't today, that means we probably passed midnight and need to refresh the data.
+            // So do that.
+            if !Calendar.current.isDateInToday(lastRefreshed ?? Date()) {
+                Task {
+                    await getDiningData()
+                }
+            }
         }
     }
     
@@ -142,61 +212,7 @@ struct ContentView: View {
                             }
                         })
                         Section(content: {
-                            ForEach(filteredLocations, id: \.self) { location in
+                            LocationList(filteredLocations: filteredLocations)
-                                NavigationLink(destination: DetailView(location: location)) {
-                                    VStack(alignment: .leading) {
-                                        HStack {
-                                            Text(location.name)
-                                            if favorites.contains(location) {
-                                                Image(systemName: "star.fill")
-                                                    .foregroundStyle(.yellow)
-                                            }
-                                        }
-                                        switch location.open {
-                                        case .open:
-                                            Text("Open")
-                                                .foregroundStyle(.green)
-                                        case .closed:
-                                            Text("Closed")
-                                                .foregroundStyle(.red)
-                                        case .openingSoon:
-                                            Text("Opening Soon")
-                                                .foregroundStyle(.orange)
-                                        case .closingSoon:
-                                            Text("Closing Soon")
-                                                .foregroundStyle(.orange)
-                                        }
-                                        if let times = location.diningTimes, !times.isEmpty {
-                                            ForEach(times, id: \.self) { time in
-                                                Text("\(dateDisplay.string(from: time.openTime)) - \(dateDisplay.string(from: time.closeTime))")
-                                                    .foregroundStyle(.secondary)
-                                            }
-                                        } else {
-                                            Text("Not Open Today")
-                                                .foregroundStyle(.secondary)
-                                        }
-                                    }
-                                }
-                                .swipeActions {
-                                    Button(action: {
-                                        withAnimation {
-                                            if favorites.contains(location) {
-                                                favorites.remove(location)
-                                            } else {
-                                                favorites.add(location)
-                                            }
-                                        }
-                                        
-                                    }) {
-                                        if favorites.contains(location) {
-                                            Label("Unfavorite", systemImage: "star")
-                                        } else {
-                                            Label("Favorite", systemImage: "star")
-                                        }
-                                    }
-                                    .tint(favorites.contains(location) ? .yellow : nil)
-                                }
-                            }
                         }, footer: {
                             if let lastRefreshed {
                                 VStack(alignment: .center) {

RIT Dining/Data/FetchData.swift

@@ -11,117 +11,88 @@ enum InvalidHTTPError: Error {
     case invalid
 }
 
-// This API requesting code came from another project of mine and was used to fetch the GitHub API for update checking. I just copied it
+// This code has now been mostly rewritten to be pretty and async instead of being horrifying callback based code in a context where
-// here, but it can probably be made simpler for this use case.
+// callback based code made no sense. I love async!
-
 // Get information for all dining locations.
-func getAllDiningInfo(date: String?, completionHandler: @escaping (Result<DiningLocationsParser, Error>) -> Void) {
+func getAllDiningInfo(date: String?) async -> Result<DiningLocationsParser, Error> {
     // The endpoint requires that you specify a date, so get today's.
-    let date_string: String = date ?? getAPIFriendlyDateString(date: Date())
+    let dateString: String = date ?? getAPIFriendlyDateString(date: Date())
-    let url_string = "https://tigercenter.rit.edu/tigerCenterApi/tc/dining-all?date=\(date_string)"
+    let urlString = "https://tigercenter.rit.edu/tigerCenterApi/tc/dining-all?date=\(dateString)"
     
-    guard let url = URL(string: url_string) else {
+    guard let url = URL(string: urlString) else {
-        print("Invalid URL")
+        return .failure(URLError(.badURL))
-        return
-    }
-    let request = URLRequest(url: url)
-    
-    URLSession.shared.dataTask(with: request) { data, response, error in
-        if let error = error {
-            completionHandler(.failure(error))
-            return
     }
 
-        guard let data = data else {
+    do {
-            completionHandler(.failure(URLError(.badServerResponse)))
+        let (data, response) = try await URLSession.shared.data(from: url)
-            return
+        
+        guard let httpResponse = response as? HTTPURLResponse,
+              (200...299).contains(httpResponse.statusCode) else {
+            return .failure(InvalidHTTPError.invalid)
         }
         
-        guard let httpResponse = response as? HTTPURLResponse, (200...299).contains(httpResponse.statusCode) else {
+        let decoded = try JSONDecoder().decode(DiningLocationsParser.self, from: data)
-            completionHandler(.failure(InvalidHTTPError.invalid))
+        return .success(decoded)
-            return
+    } catch {
+        return .failure(error)
     }
-        
-        let decoded: Result<DiningLocationsParser, Error> = Result(catching: { try JSONDecoder().decode(DiningLocationsParser.self, from: data) })
-        completionHandler(decoded)
-    }.resume()
 }
 
 // Get information for just one dining location based on its location ID.
-func getSingleDiningInfo(date: String?, locationId: Int, completionHandler: @escaping (Result<DiningLocationParser, Error>) -> Void) {
+func getSingleDiningInfo(date: String?, locId: Int) async -> Result<DiningLocationParser, Error> {
     // The current date and the location ID are required to get information for just one location.
-    let date_string: String = date ?? getAPIFriendlyDateString(date: Date())
+    let dateString: String = date ?? getAPIFriendlyDateString(date: Date())
-    let url_string = "https://tigercenter.rit.edu/tigerCenterApi/tc/dining-single?date=\(date_string)&locId=\(locationId)"
+    let urlString = "https://tigercenter.rit.edu/tigerCenterApi/tc/dining-single?date=\(dateString)&locId=\(locId)"
-    print("making request to \(url_string)")
+    print("making request to \(urlString)")
 
-    guard let url = URL(string: url_string) else {
+    guard let url = URL(string: urlString) else {
-        print("Invalid URL")
+        return .failure(URLError(.badURL))
-        return
-    }
-    let request = URLRequest(url: url)
-    
-    URLSession.shared.dataTask(with: request) { data, response, error in
-        if let error = error {
-            completionHandler(.failure(error))
-            return
     }
 
-        guard let data = data else {
+    do {
-            completionHandler(.failure(URLError(.badServerResponse)))
+        let (data, response) = try await URLSession.shared.data(from: url)
-            return
+        
+        guard let httpResponse = response as? HTTPURLResponse,
+              (200...299).contains(httpResponse.statusCode) else {
+            return .failure(InvalidHTTPError.invalid)
         }
         
-        guard let httpResponse = response as? HTTPURLResponse, (200...299).contains(httpResponse.statusCode) else {
+        let decoded = try JSONDecoder().decode(DiningLocationParser.self, from: data)
-            completionHandler(.failure(InvalidHTTPError.invalid))
+        return .success(decoded)
-            return
+    } catch {
+        return .failure(error)
     }
-        
-        let decoded: Result<DiningLocationParser, Error> = Result(catching: { try JSONDecoder().decode(DiningLocationParser.self, from: data) })
-        completionHandler(decoded)
-    }.resume()
 }
 
-// Get the occupancy information for a location using its MDO ID, whatever that stands for. This ID is provided alongside the other main
+// Get the occupancy information for a location using its MDO ID, whatever that stands for. This ID is provided alongside the other
-// ID in the data returned by the TigerCenter API.
+// main ID in the data returned by the TigerCenter API.
-func getOccupancyPercentage(mdoId: Int, completionHandler: @escaping (Result<Double, Error>) -> Void) {
+func getOccupancyPercentage(mdoId: Int) async -> Result<Double, Error> {
     let urlString = "https://maps.rit.edu/proxySearch/densityMapDetail.php?mdo=\(mdoId)"
     print("making request to \(urlString)")
     
     guard let url = URL(string: urlString) else {
-        print("Invalid URL")
+        return .failure(URLError(.badURL))
-        return
-    }
-    let occRequest = URLRequest(url: url)
-    
-    URLSession.shared.dataTask(with: occRequest) { data, response, error in
-        if let error = error {
-            completionHandler(.failure(error))
-            return
-        }
-        
-        guard let data = data else {
-            completionHandler(.failure(URLError(.badServerResponse)))
-            return
-        }
-        
-        guard let httpResponse = response as? HTTPURLResponse, (200...299).contains(httpResponse.statusCode) else {
-            completionHandler(.failure(InvalidHTTPError.invalid))
-            return
     }
     
     do {
+        let (data, response) = try await URLSession.shared.data(from: url)
+        
+        guard let httpResponse = response as? HTTPURLResponse,
+              (200...299).contains(httpResponse.statusCode) else {
+            return .failure(InvalidHTTPError.invalid)
+        }
+        
         let occupancy = try JSONDecoder().decode([DiningOccupancyParser].self, from: data)
         if !occupancy.isEmpty {
             print("current occupancy: \(occupancy[0].count)")
             print("maximum occupancy: \(occupancy[0].max_occ)")
             let occupancyPercentage = Double(occupancy[0].count) / Double(occupancy[0].max_occ) * 100
             print("occupancy percentage: \(occupancyPercentage)%")
-                completionHandler(.success(occupancyPercentage))
+            return .success(occupancyPercentage)
         } else {
-                completionHandler(.failure(DecodingError.dataCorrupted(DecodingError.Context(codingPath: [], debugDescription: "Failed to decode JSON"))))
+            return .failure(DecodingError.dataCorrupted(DecodingError.Context(codingPath: [], debugDescription: "Failed to decode JSON")))
         }
     } catch {
-            completionHandler(.failure(DecodingError.dataCorrupted(DecodingError.Context(codingPath: [], debugDescription: "Failed to decode JSON"))))
+        return .failure(error)
     }
-    }.resume()
 }

RIT Dining/Views/DetailView.swift

@@ -9,17 +9,15 @@ import SwiftUI
 import SafariServices
 
 struct DetailView: View {
-    @State var location: DiningLocation
+    @Binding var location: DiningLocation
     @Environment(Favorites.self) var favorites
     @State private var isLoading: Bool = true
     @State private var rotationDegrees: Double = 0
     @State private var showingSafari: Bool = false
     @State private var openString: String = ""
-    @State private var week: [Date] = []
     @State private var weeklyHours: [[String]] = []
     @State private var occupancyLoading: Bool = true
     @State private var occupancyPercentage: Double = 0.0
-    @State private var focusedDate: Date = Date()
     private let daysOfWeek = ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"]
     
     private var animation: Animation {
@@ -28,76 +26,63 @@ struct DetailView: View {
         .repeatForever(autoreverses: false)
     }
     
-    private func requestDone(result: Result<DiningLocationParser, Error>) -> Void {
+    // This function is now actaully async and iterative! Wow! It doesn't suck ass anymore!
-        switch result {
+    private func getWeeklyHours() async {
+        let calendar = Calendar.current
+        let today = calendar.startOfDay(for: Date())
+        let dayOfWeek = calendar.component(.weekday, from: today)
+        let week = calendar.range(of: .weekday, in: .weekOfYear, for: today)!
+            .compactMap { calendar.date(byAdding: .day, value: $0 - dayOfWeek, to: today) }
+        var newWeeklyHours: [[String]] = []
+        for day in week {
+            let date_string = day.formatted(.iso8601
+                .year().month().day()
+                .dateSeparator(.dash))
+            switch await getSingleDiningInfo(date: date_string, locId: location.id) {
             case .success(let location):
-            let diningInfo = parseLocationInfo(location: location, forDate: focusedDate)
+                let diningInfo = parseLocationInfo(location: location, forDate: day)
                 if let times = diningInfo.diningTimes, !times.isEmpty {
                     var timeStrings: [String] = []
                     for time in times {
                         timeStrings.append("\(dateDisplay.string(from: time.openTime)) - \(dateDisplay.string(from: time.closeTime))")
                     }
-                weeklyHours.append(timeStrings)
+                    newWeeklyHours.append(timeStrings)
                 } else {
-                weeklyHours.append(["Closed"])
+                    newWeeklyHours.append(["Closed"])
                 }
             case .failure(let error):
                 print(error)
             }
-        if week.count > 0 {
-            // Saving this to a state variable SUCKS, but I needed a quick fix and all of this request code is still pending a
-            // rewrite anyway to be properly async like the code in ContentView and VisitingChefs.
-            focusedDate = week.removeFirst()
-            DispatchQueue.global().async {
-                let dateString = focusedDate.formatted(.iso8601
-                    .year().month().day()
-                    .dateSeparator(.dash))
-                getSingleDiningInfo(date: dateString, locationId: location.id, completionHandler: requestDone)
         }
-        } else {
+        weeklyHours = newWeeklyHours
         isLoading = false
         print(weeklyHours)
     }
-    }
     
-    private func getWeeklyHours() {
+    private func getOccupancy() async {
-        let calendar = Calendar.current
-        let today = calendar.startOfDay(for: Date())
-        let dayOfWeek = calendar.component(.weekday, from: today)
-        week = calendar.range(of: .weekday, in: .weekOfYear, for: today)!
-            .compactMap { calendar.date(byAdding: .day, value: $0 - dayOfWeek, to: today) }
-        DispatchQueue.global().async {
-            let date_string = week.removeFirst().formatted(.iso8601
-                .year().month().day()
-                .dateSeparator(.dash))
-            getSingleDiningInfo(date: date_string, locationId: location.id, completionHandler: requestDone)
-        }
-    }
-    
-    private func getOccupancy() {
         // Only fetch occupancy data if the location is actually open right now. Otherwise, just exit early and hide the spinner.
         if location.open == .open || location.open == .closingSoon {
-            DispatchQueue.main.async {
+            occupancyLoading = true
-                getOccupancyPercentage(mdoId: location.mdoId) { result in
+            switch await getOccupancyPercentage(mdoId: location.mdoId) {
-                    switch result {
             case .success(let occupancy):
-                        DispatchQueue.main.sync {
                 occupancyPercentage = occupancy
                 occupancyLoading = false
-                        }
             case .failure(let error):
                 print(error)
-                        DispatchQueue.main.sync {
                 occupancyLoading = false
             }
-                    }
-                }
-            }
         } else {
             occupancyLoading = false
         }
     }
     
+    // Same label update timer from ContentView.
+    private func updateOpenStatuses() async {
+        Timer.scheduledTimer(withTimeInterval: 3, repeats: true) { _ in
+            location.updateOpenStatus()
+        }
+    }
+    
     var body: some View {
         if isLoading {
             VStack {
@@ -114,8 +99,8 @@ struct DetailView: View {
                 Text("Loading...")
                     .foregroundStyle(.secondary)
             }
-            .onAppear {
+            .task {
-                getWeeklyHours()
+                await getWeeklyHours()
             }
             .padding()
         } else {
@@ -200,8 +185,8 @@ struct DetailView: View {
                             .progressViewStyle(.circular)
                             .frame(width: 18, height: 18)
                             .opacity(occupancyLoading ? 1 : 0)
-                            .onAppear {
+                            .task {
-                                getOccupancy()
+                                await getOccupancy()
                             }
                     }
                     .foregroundStyle(Color.accent.opacity(occupancyLoading ? 0.5 : 1.0))
@@ -294,20 +279,24 @@ struct DetailView: View {
             .sheet(isPresented: $showingSafari) {
                 SafariView(url: URL(string: location.mapsUrl)!)
             }
+            .refreshable {
+                await getWeeklyHours()
+                await getOccupancy()
+            }
         }
     }
 }
 
-#Preview {
+//#Preview {
-    DetailView(location: DiningLocation(
+//    DetailView(location: DiningLocation(
-        id: 0,
+//        id: 0,
-        mdoId: 0,
+//        mdoId: 0,
-        name: "Example",
+//        name: "Example",
-        summary: "A Place",
+//        summary: "A Place",
-        desc: "A long description of the place",
+//        desc: "A long description of the place",
-        mapsUrl: "https://example.com",
+//        mapsUrl: "https://example.com",
-        diningTimes: [DiningTimes(openTime: Date(), closeTime: Date())],
+//        diningTimes: [DiningTimes(openTime: Date(), closeTime: Date())],
-        open: .open,
+//        open: .open,
-        visitingChefs: nil,
+//        visitingChefs: nil,
-        dailySpecials: nil))
+//        dailySpecials: nil))
-}
+//}

RIT Dining/Views/VisitingChefs.swift

@@ -30,8 +30,7 @@ struct VisitingChefs: View {
     // information.
     private func getDiningDataForDate(date: String) async {
         var newDiningLocations: [DiningLocation] = []
-        getAllDiningInfo(date: date) { result in
+        switch await getAllDiningInfo(date: date) {
-            switch result {
         case .success(let locations):
             for i in 0..<locations.locations.count {
                 let diningInfo = parseLocationInfo(location: locations.locations[i], forDate: nil)
@@ -43,8 +42,8 @@ struct VisitingChefs: View {
             }
             locationsWithChefs = newDiningLocations
             isLoading = false
-            case .failure(let error): print(error)
+        case .failure(let error):
-            }
+            print(error)
         }
     }