import XCTest
@testable import RouterOSAssistant

final class SavedRoutersStoreTests: XCTestCase {
    /// A dedicated suite name per test avoids bleeding state between tests / real app defaults.
    private func makeStore() -> SavedRoutersStore {
        let suiteName = "SavedRoutersStoreTests.\(UUID().uuidString)"
        let defaults = UserDefaults(suiteName: suiteName)!
        return SavedRoutersStore(defaults: defaults)
    }

    func testFirstSuccessfulConnectionAddsEntryWithDefaultName() {
        let store = makeStore()
        let routers = store.recordSuccessfulConnection(host: "192.168.88.1", username: "admin", defaultName: "hEX")

        XCTAssertEqual(routers.count, 1)
        XCTAssertEqual(routers[0].host, "192.168.88.1")
        XCTAssertEqual(routers[0].username, "admin")
        XCTAssertEqual(routers[0].name, "hEX")
        XCTAssertEqual(routers[0].location, "")
    }

    func testUpdateLocationRoundTrip() {
        let store = makeStore()
        store.recordSuccessfulConnection(host: "192.168.88.1", username: "admin", defaultName: "hEX")
        let id = store.load()[0].id

        let updated = store.updateLocation(id, to: "Keller, Serverschrank")
        XCTAssertEqual(updated.first?.location, "Keller, Serverschrank")
        // Renaming afterwards must not clobber the location, and vice versa.
        let renamed = store.rename(id, to: "Hauptrouter")
        XCTAssertEqual(renamed.first?.name, "Hauptrouter")
        XCTAssertEqual(renamed.first?.location, "Keller, Serverschrank")
    }

    /// A list saved by an earlier app version (before `location` existed) must keep loading
    /// instead of the whole list silently vanishing — see `SavedRouter.init(from:)`.
    func testDecodingAnEntryWithoutALocationFieldDefaultsToEmpty() {
        let suiteName = "SavedRoutersStoreTests.\(UUID().uuidString)"
        let defaults = UserDefaults(suiteName: suiteName)!
        let legacyJSON = """
        [{"id":"\(UUID().uuidString)","host":"192.168.88.1","username":"admin","name":"hEX","lastConnectedAt":0}]
        """
        defaults.set(Data(legacyJSON.utf8), forKey: "RouterOSAssistant.SavedRouters")

        let store = SavedRoutersStore(defaults: defaults)
        let routers = store.load()

        XCTAssertEqual(routers.count, 1)
        XCTAssertEqual(routers[0].name, "hEX")
        XCTAssertEqual(routers[0].location, "")
    }

    func testReconnectingToKnownRouterUpdatesRecencyNotName() {
        let store = makeStore()
        store.recordSuccessfulConnection(host: "192.168.88.1", username: "admin", defaultName: "hEX")
        store.rename(store.load()[0].id, to: "Büro-Router")

        // A later connection reports a possibly-different board name (e.g. after a hardware
        // swap behind the same IP) — the user's own rename must survive regardless.
        let routers = store.recordSuccessfulConnection(host: "192.168.88.1", username: "admin", defaultName: "RB750Gr3")

        XCTAssertEqual(routers.count, 1)
        XCTAssertEqual(routers[0].name, "Büro-Router")
    }

    func testDifferentUsernameOnSameHostIsATwoEntries() {
        let store = makeStore()
        store.recordSuccessfulConnection(host: "192.168.88.1", username: "admin", defaultName: "hEX")
        let routers = store.recordSuccessfulConnection(host: "192.168.88.1", username: "gast", defaultName: "hEX")

        XCTAssertEqual(routers.count, 2)
    }

    func testRenameAndRemoveRoundTrip() {
        let store = makeStore()
        store.recordSuccessfulConnection(host: "192.168.88.1", username: "admin", defaultName: "hEX")
        let id = store.load()[0].id

        let renamed = store.rename(id, to: "Wohnzimmer")
        XCTAssertEqual(renamed.first?.name, "Wohnzimmer")

        let removed = store.remove(id)
        XCTAssertTrue(removed.isEmpty)
        XCTAssertTrue(store.load().isEmpty)
    }

    /// Live-confirmed (2026-09-16): a second, same-model router left at MikroTik's factory
    /// default (192.168.88.1/admin) previously just renamed the *existing* entry from the first
    /// router in place, with no way to tell the two physical devices apart afterwards.
    func testDifferentSerialAtSameHostUsernameCreatesSeparateEntry() {
        let store = makeStore()
        store.recordSuccessfulConnection(host: "192.168.88.1", username: "admin", defaultName: "hEX", serialNumber: "AAA111")
        let routers = store.recordSuccessfulConnection(host: "192.168.88.1", username: "admin", defaultName: "hEX", serialNumber: "BBB222")

        XCTAssertEqual(routers.count, 2)
    }

    /// A router saved before `serialNumber` existed (or from a device with no routerboard) has
    /// no recorded serial yet — the next connection that DOES report one should fill it in on
    /// the same entry rather than creating a duplicate.
    func testLegacyEntryWithoutSerialGetsUpgradedInPlaceNotDuplicated() {
        let store = makeStore()
        store.recordSuccessfulConnection(host: "192.168.88.1", username: "admin", defaultName: "hEX", serialNumber: nil)
        let routers = store.recordSuccessfulConnection(host: "192.168.88.1", username: "admin", defaultName: "hEX", serialNumber: "AAA111")

        XCTAssertEqual(routers.count, 1)
        XCTAssertEqual(routers[0].serialNumber, "AAA111")
    }

    func testSameSerialReconnectUpdatesRecencyNotDuplicated() {
        let store = makeStore()
        store.recordSuccessfulConnection(host: "192.168.88.1", username: "admin", defaultName: "hEX", serialNumber: "AAA111")
        let routers = store.recordSuccessfulConnection(host: "192.168.88.1", username: "admin", defaultName: "hEX", serialNumber: "AAA111")

        XCTAssertEqual(routers.count, 1)
    }

    func testLoadOrdersMostRecentlyConnectedFirst() {
        let store = makeStore()
        store.recordSuccessfulConnection(host: "10.0.0.1", username: "admin", defaultName: "Router A")
        store.recordSuccessfulConnection(host: "10.0.0.2", username: "admin", defaultName: "Router B")
        // Reconnecting to the first one should move it back to the front.
        let routers = store.recordSuccessfulConnection(host: "10.0.0.1", username: "admin", defaultName: "Router A")

        XCTAssertEqual(routers.first?.host, "10.0.0.1")
    }
}