Search improvements for iOS

Model/RecentsModel.swift

@@ -0,0 +1,126 @@
+import Defaults
+import Foundation
+
+final class RecentsModel: ObservableObject {
+    @Default(.recentlyOpened) var items
+
+    var isEmpty: Bool {
+        items.isEmpty
+    }
+
+    func clear() {
+        items = []
+    }
+
+    func clearQueries() {
+        items.removeAll { $0.type == .query }
+    }
+
+    func open(_ item: RecentItem) {
+        if !items.contains(where: { $0.id == item.id }) {
+            items.append(item)
+        }
+    }
+
+    func close(_ item: RecentItem) {
+        if let index = items.firstIndex(where: { $0.id == item.id }) {
+            items.remove(at: index)
+        }
+    }
+
+    func addQuery(_ query: String) {
+        open(.init(from: query))
+    }
+
+    var presentedChannel: Channel? {
+        if let recent = items.last(where: { $0.type == .channel }) {
+            return recent.channel
+        }
+
+        return nil
+    }
+}
+
+struct RecentItem: Defaults.Serializable, Identifiable {
+    static var bridge = RecentItemBridge()
+
+    enum ItemType: String {
+        case channel, query
+    }
+
+    var type: ItemType
+    var id: String
+    var title: String
+
+    var tag: String {
+        "recent\(type.rawValue.capitalized)\(id)"
+    }
+
+    var query: SearchQuery? {
+        guard type == .query else {
+            return nil
+        }
+
+        return SearchQuery(query: title)
+    }
+
+    var channel: Channel? {
+        guard type == .channel else {
+            return nil
+        }
+
+        return Channel(id: id, name: title)
+    }
+
+    init(type: ItemType, identifier: String, title: String) {
+        self.type = type
+        id = identifier
+        self.title = title
+    }
+
+    init(from channel: Channel) {
+        type = .channel
+        id = channel.id
+        title = channel.name
+    }
+
+    init(from query: String) {
+        type = .query
+        id = query
+        title = query
+    }
+}
+
+struct RecentItemBridge: Defaults.Bridge {
+    typealias Value = RecentItem
+    typealias Serializable = [String: String]
+
+    func serialize(_ value: Value?) -> Serializable? {
+        guard let value = value else {
+            return nil
+        }
+
+        return [
+            "type": value.type.rawValue,
+            "identifier": value.id,
+            "title": value.title
+        ]
+    }
+
+    func deserialize(_ object: Serializable?) -> Value? {
+        guard
+            let object = object,
+            let type = object["type"],
+            let identifier = object["identifier"],
+            let title = object["title"]
+        else {
+            return nil
+        }
+
+        return RecentItem(
+            type: .init(rawValue: type)!,
+            identifier: identifier,
+            title: title
+        )
+    }
+}