UI improvements, player state refactor

Fixtures/Thumbnail+Fixtures.swift

@@ -0,0 +1,36 @@
+import Foundation
+
+extension Thumbnail {
+    static func fixture(videoId: String, quality: Thumbnail.Quality = .maxres) -> Thumbnail {
+        Thumbnail(url: fixtureUrl(videoId: videoId, quality: quality), quality: quality)
+    }
+
+    static func fixturesForAllQualities(videoId: String) -> [Thumbnail] {
+        Thumbnail.Quality.allCases.map { fixture(videoId: videoId, quality: $0) }
+    }
+
+    private static var fixturesHost: String {
+        "https://invidious.home.arekf.net"
+    }
+
+    private static func fixtureUrl(videoId: String, quality: Thumbnail.Quality) -> URL {
+        URL(string: "\(fixturesHost)/vi/\(videoId)/\(filenameForQuality(quality)).jpg")!
+    }
+
+    private static func filenameForQuality(_ quality: Thumbnail.Quality) -> String {
+        switch quality {
+        case .high:
+            return "hqdefault"
+        case .medium:
+            return "mqdefault"
+        case .start:
+            return "1"
+        case .middle:
+            return "2"
+        case .end:
+            return "3"
+        default:
+            return quality.rawValue
+        }
+    }
+}