Tools/SwiftBrowser/Source/ViewModel/FeatureFlagsModel.swift

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import Observation
import WebKit_Private.WKPreferencesPrivate

@Observable
@MainActor
final class FeatureFlagsModel {
    typealias GroupedFeatures = [(category: WebFeatureCategory, features: [_WKFeature])]

    var searchQuery = ""

    var customizedFeatures = FeatureFlagsStorage.shared.resolve(keys: WKPreferences._features())

    private let groups: GroupedFeatures = Dictionary(grouping: WKPreferences._features(), by: \.category)
        .map { (category: $0, features: $1) }
        .filter { $0.category != .none }
        .sorted { $0.category < $1.category }

    func groups(filteredBy query: String) -> GroupedFeatures {
        groups.compactMap { group in
            guard !query.isEmpty else {
                return group
            }

            let filteredFeatures = group.features.filter {
                $0.name.localizedCaseInsensitiveContains(query)
            }

            guard !filteredFeatures.isEmpty else {
                return nil
            }

            return (
                category: group.category,
                features: filteredFeatures
            )
        }
    }

    func update(oldValue: _WKFeature.Collection, newValue: _WKFeature.Collection) {
        FeatureFlagsStorage<_WKFeature>.shared.update(mergingOldEntries: oldValue, with: newValue)
    }
}