Channels search, add SDWebImage framework

Model/ContentItem.swift

@@ -0,0 +1,48 @@
+import Foundation
+
+struct ContentItem: Identifiable {
+    enum ContentType: String {
+        case video, playlist, channel
+
+        private var sortOrder: Int {
+            switch self {
+            case .channel:
+                return 1
+            case .video:
+                return 2
+            default:
+                return 3
+            }
+        }
+
+        static func < (lhs: ContentType, rhs: ContentType) -> Bool {
+            lhs.sortOrder < rhs.sortOrder
+        }
+    }
+
+    var video: Video!
+    var playlist: Playlist!
+    var channel: Channel!
+
+    static func array(of videos: [Video]) -> [ContentItem] {
+        videos.map { ContentItem(video: $0) }
+    }
+
+    static func < (lhs: ContentItem, rhs: ContentItem) -> Bool {
+        lhs.contentType < rhs.contentType
+    }
+
+    var id: String {
+        "\(contentType.rawValue)-\(video?.id ?? playlist?.id ?? channel?.id ?? "")"
+    }
+
+    var contentType: ContentType {
+        if !playlist.isNil {
+            return .playlist
+        } else if !channel.isNil {
+            return .channel
+        }
+
+        return .video
+    }
+}