RouterOS/RouterOSAssistant/Core/Services/SavedRoutersStore.swift

import Foundation

/// Persists the Verbinden-Tab's "known routers" list (host/username/editable name/last-connected)
/// as JSON in UserDefaults — small, structured data, no reason for its own file the way backups
/// get a directory. Passwords themselves stay exactly where they already did: the macOS Keychain
/// via `KeychainService`, keyed by "username@host", untouched by this store.
struct SavedRoutersStore {
    private static let key = "RouterOSAssistant.SavedRouters"
    private let defaults: UserDefaults

    init(defaults: UserDefaults = .standard) {
        self.defaults = defaults
    }

    /// Most recently used first.
    func load() -> [SavedRouter] {
        sortedByRecency(loadRaw())
    }

    private func loadRaw() -> [SavedRouter] {
        guard let data = defaults.data(forKey: Self.key),
              let routers = try? JSONDecoder().decode([SavedRouter].self, from: data) else { return [] }
        return routers
    }

    private func sortedByRecency(_ routers: [SavedRouter]) -> [SavedRouter] {
        routers.sorted { $0.lastConnectedAt > $1.lastConnectedAt }
    }

    /// Persists in whatever order given, then returns the recency-sorted view — every public
    /// method's return value has the same "most recently used first" order as `load()`, so a
    /// caller can always assign it straight to a displayed list without a separate re-sort.
    @discardableResult
    private func save(_ routers: [SavedRouter]) -> [SavedRouter] {
        if let data = try? JSONEncoder().encode(routers) {
            defaults.set(data, forKey: Self.key)
        }
        return sortedByRecency(routers)
    }

    /// Called after a successful connection: adds a new entry (name defaulting to `defaultName`)
    /// if this host/username pair isn't known yet, or just bumps `lastConnectedAt` on the existing
    /// one. An existing entry's `name` is never touched here — that's what preserves a user's own
    /// rename across later reconnects.
    @discardableResult
    func recordSuccessfulConnection(host: String, username: String, defaultName: String) -> [SavedRouter] {
        var routers = loadRaw()
        if let index = routers.firstIndex(where: { $0.host == host && $0.username == username }) {
            routers[index].lastConnectedAt = Date()
        } else {
            routers.append(SavedRouter(host: host, username: username, name: defaultName))
        }
        return save(routers)
    }

    @discardableResult
    func rename(_ id: SavedRouter.ID, to newName: String) -> [SavedRouter] {
        var routers = loadRaw()
        guard let index = routers.firstIndex(where: { $0.id == id }) else { return sortedByRecency(routers) }
        routers[index].name = newName
        return save(routers)
    }

    /// Free-text location/purpose (e.g. "Keller" or "1. OG") — kept as its own method rather than
    /// folded into `rename` since a caller may want to update just one of the two, and it mirrors
    /// `rename`'s exact shape.
    @discardableResult
    func updateLocation(_ id: SavedRouter.ID, to newLocation: String) -> [SavedRouter] {
        var routers = loadRaw()
        guard let index = routers.firstIndex(where: { $0.id == id }) else { return sortedByRecency(routers) }
        routers[index].location = newLocation
        return save(routers)
    }

    @discardableResult
    func remove(_ id: SavedRouter.ID) -> [SavedRouter] {
        var routers = loadRaw()
        routers.removeAll { $0.id == id }
        return save(routers)
    }
}