Revert "fix: use native ISO 8601 date formatter (#30)"

This reverts commit 0b20f2501f474ea318f187667097a409808afbc7.

Sources/JellyfinClient.swift

@@ -41,8 +41,7 @@ public final class JellyfinClient {
             configuration.delegate = self
             configuration.sessionDelegate = sessionDelegate
 
-            let isoDateFormatter: DateFormatter = ISO8601DateFormatter()
-            isoDateFormatter.formatOptions = .withFractionalSeconds
+            let isoDateFormatter: DateFormatter = OpenISO8601DateFormatter()
 
             let decoder = JSONDecoder()
             decoder.dateDecodingStrategy = .formatted(isoDateFormatter)

Sources/OpenISO8601Formatter.swift

@@ -0,0 +1,45 @@
+//
+// jellyfin-sdk-swift is subject to the terms of the Mozilla Public
+// License, v2.0. If a copy of the MPL was not distributed with this
+// file, you can obtain one at https://mozilla.org/MPL/2.0/.
+//
+// Copyright (c) 2023 Jellyfin & Jellyfin Contributors
+//
+
+import Foundation
+
+// https://stackoverflow.com/a/50281094/976628
+public class OpenISO8601DateFormatter: DateFormatter {
+    static let withoutSeconds: DateFormatter = {
+        let formatter = DateFormatter()
+        formatter.calendar = Calendar(identifier: .iso8601)
+        formatter.locale = Locale(identifier: "en_US_POSIX")
+        formatter.timeZone = TimeZone(secondsFromGMT: 0)
+        formatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZZZZZ"
+        return formatter
+    }()
+
+    private func setup() {
+        calendar = Calendar(identifier: .iso8601)
+        locale = Locale(identifier: "en_US_POSIX")
+        timeZone = TimeZone(secondsFromGMT: 0)
+        dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSSZZZZZ"
+    }
+
+    override init() {
+        super.init()
+        setup()
+    }
+
+    required init?(coder aDecoder: NSCoder) {
+        super.init(coder: aDecoder)
+        setup()
+    }
+
+    override public func date(from string: String) -> Date? {
+        if let result = super.date(from: string) {
+            return result
+        }
+        return OpenISO8601DateFormatter.withoutSeconds.date(from: string)
+    }
+}