//
//  TripWizardViewModelTests.swift
//  SportsTimeTests
//

import XCTest
@testable import SportsTime

final class TripWizardViewModelTests: XCTestCase {

    func test_initialState_onlyPlanningModeStepVisible() {
        let viewModel = TripWizardViewModel()

        XCTAssertTrue(viewModel.isPlanningModeStepVisible)
        XCTAssertFalse(viewModel.isSportsStepVisible)
        XCTAssertFalse(viewModel.isDatesStepVisible)
        XCTAssertFalse(viewModel.isRegionsStepVisible)
    }

    func test_selectingPlanningMode_revealsSportsStep() {
        let viewModel = TripWizardViewModel()

        viewModel.planningMode = .dateRange

        XCTAssertTrue(viewModel.isSportsStepVisible)
    }

    func test_selectingSport_revealsDatesStep() {
        let viewModel = TripWizardViewModel()
        viewModel.planningMode = .dateRange

        viewModel.selectedSports = [.mlb]

        XCTAssertTrue(viewModel.isDatesStepVisible)
    }

    func test_changingPlanningMode_resetsDownstreamSelections() {
        let viewModel = TripWizardViewModel()
        viewModel.planningMode = .dateRange
        viewModel.selectedSports = [.mlb, .nba]
        viewModel.hasSetDates = true

        viewModel.planningMode = .gameFirst

        XCTAssertTrue(viewModel.selectedSports.isEmpty)
        XCTAssertFalse(viewModel.hasSetDates)
    }

    // MARK: - Full Flow Integration Tests

    func test_fullWizardFlow_reachesReviewStep() {
        let viewModel = TripWizardViewModel()

        // Step 1: Select planning mode
        viewModel.planningMode = .dateRange
        XCTAssertTrue(viewModel.isSportsStepVisible)

        // Step 2: Select sport
        viewModel.selectedSports = [.mlb]
        XCTAssertTrue(viewModel.isDatesStepVisible)

        // Step 3: Set dates
        viewModel.hasSetDates = true
        XCTAssertTrue(viewModel.isRegionsStepVisible)

        // Step 4: Select regions
        viewModel.selectedRegions = [.east]
        XCTAssertTrue(viewModel.isRoutePreferenceStepVisible)

        // Step 5: Set route preference
        viewModel.hasSetRoutePreference = true
        XCTAssertTrue(viewModel.isRepeatCitiesStepVisible)

        // Step 6: Set repeat cities preference
        viewModel.hasSetRepeatCities = true
        XCTAssertTrue(viewModel.isMustStopsStepVisible)
        XCTAssertTrue(viewModel.isReviewStepVisible)
    }

    func test_regionSelection_revealsRoutePreference() {
        let viewModel = TripWizardViewModel()
        viewModel.planningMode = .dateRange
        viewModel.selectedSports = [.nba]
        viewModel.hasSetDates = true

        XCTAssertFalse(viewModel.isRoutePreferenceStepVisible)

        viewModel.selectedRegions = [.central, .west]

        XCTAssertTrue(viewModel.isRoutePreferenceStepVisible)
    }

    func test_routePreference_revealsRepeatCities() {
        let viewModel = TripWizardViewModel()
        viewModel.planningMode = .dateRange
        viewModel.selectedSports = [.mlb]
        viewModel.hasSetDates = true
        viewModel.selectedRegions = [.east]

        XCTAssertFalse(viewModel.isRepeatCitiesStepVisible)

        viewModel.hasSetRoutePreference = true

        XCTAssertTrue(viewModel.isRepeatCitiesStepVisible)
    }

    func test_repeatCities_revealsMustStopsAndReview() {
        let viewModel = TripWizardViewModel()
        viewModel.planningMode = .dateRange
        viewModel.selectedSports = [.mlb]
        viewModel.hasSetDates = true
        viewModel.selectedRegions = [.east]
        viewModel.hasSetRoutePreference = true

        XCTAssertFalse(viewModel.isMustStopsStepVisible)
        XCTAssertFalse(viewModel.isReviewStepVisible)

        viewModel.hasSetRepeatCities = true

        XCTAssertTrue(viewModel.isMustStopsStepVisible)
        XCTAssertTrue(viewModel.isReviewStepVisible)
    }

    // MARK: - Reset Behavior Tests

    func test_changingPlanningMode_resetsAllDownstreamState() {
        let viewModel = TripWizardViewModel()

        // Set up full wizard state
        viewModel.planningMode = .dateRange
        viewModel.selectedSports = [.mlb, .nba]
        viewModel.hasSetDates = true
        viewModel.selectedRegions = [.east, .central]
        viewModel.hasSetRoutePreference = true
        viewModel.hasSetRepeatCities = true
        viewModel.mustStopLocations = [LocationInput(name: "Test", coordinates: nil)]

        // Change planning mode
        viewModel.planningMode = .locations

        // Verify all downstream state is reset
        XCTAssertTrue(viewModel.selectedSports.isEmpty)
        XCTAssertFalse(viewModel.hasSetDates)
        XCTAssertTrue(viewModel.selectedRegions.isEmpty)
        XCTAssertFalse(viewModel.hasSetRoutePreference)
        XCTAssertFalse(viewModel.hasSetRepeatCities)
        XCTAssertTrue(viewModel.mustStopLocations.isEmpty)
    }

    func test_settingSamePlanningMode_doesNotResetState() {
        let viewModel = TripWizardViewModel()
        viewModel.planningMode = .dateRange
        viewModel.selectedSports = [.mlb]
        viewModel.hasSetDates = true

        // Re-set the same mode
        viewModel.planningMode = .dateRange

        // State should NOT be reset
        XCTAssertEqual(viewModel.selectedSports, [.mlb])
        XCTAssertTrue(viewModel.hasSetDates)
    }

    // MARK: - Edge Cases

    func test_emptyRegionSelection_hidesRoutePreference() {
        let viewModel = TripWizardViewModel()
        viewModel.planningMode = .dateRange
        viewModel.selectedSports = [.mlb]
        viewModel.hasSetDates = true
        viewModel.selectedRegions = [.west]
        XCTAssertTrue(viewModel.isRoutePreferenceStepVisible)

        viewModel.selectedRegions = []

        XCTAssertFalse(viewModel.isRoutePreferenceStepVisible)
    }

    func test_multipleSports_canBeSelected() {
        let viewModel = TripWizardViewModel()
        viewModel.planningMode = .dateRange

        viewModel.selectedSports = [.mlb, .nba, .nhl]

        XCTAssertEqual(viewModel.selectedSports.count, 3)
        XCTAssertTrue(viewModel.isDatesStepVisible)
    }

    func test_multipleRegions_canBeSelected() {
        let viewModel = TripWizardViewModel()
        viewModel.planningMode = .dateRange
        viewModel.selectedSports = [.mlb]
        viewModel.hasSetDates = true

        viewModel.selectedRegions = [.east, .central, .west]

        XCTAssertEqual(viewModel.selectedRegions.count, 3)
        XCTAssertTrue(viewModel.isRoutePreferenceStepVisible)
    }

    // MARK: - Reveal State Bitmask Tests

    func test_revealState_initialValue() {
        let viewModel = TripWizardViewModel()

        XCTAssertEqual(viewModel.revealState, 0)
    }

    func test_revealState_incrementsWithProgress() {
        let viewModel = TripWizardViewModel()

        viewModel.planningMode = .dateRange
        XCTAssertEqual(viewModel.revealState, 1) // Sports visible

        viewModel.selectedSports = [.mlb]
        XCTAssertEqual(viewModel.revealState, 3) // Sports + Dates

        viewModel.hasSetDates = true
        XCTAssertEqual(viewModel.revealState, 7) // Sports + Dates + Regions
    }

    func test_revealState_fullFlow() {
        let viewModel = TripWizardViewModel()
        viewModel.planningMode = .dateRange
        viewModel.selectedSports = [.mlb]
        viewModel.hasSetDates = true
        viewModel.selectedRegions = [.east]
        viewModel.hasSetRoutePreference = true
        viewModel.hasSetRepeatCities = true

        // 1 + 2 + 4 + 8 + 16 + 32 + 64 = 127
        XCTAssertEqual(viewModel.revealState, 127)
    }

    // MARK: - Sport Availability Tests

    func test_canSelectSport_defaultsToTrue() {
        let viewModel = TripWizardViewModel()

        XCTAssertTrue(viewModel.canSelectSport(.mlb))
        XCTAssertTrue(viewModel.canSelectSport(.nba))
        XCTAssertTrue(viewModel.canSelectSport(.nhl))
    }

    func test_canSelectSport_respectsAvailability() {
        let viewModel = TripWizardViewModel()
        viewModel.sportAvailability = [.mlb: true, .nba: false, .nhl: true]

        XCTAssertTrue(viewModel.canSelectSport(.mlb))
        XCTAssertFalse(viewModel.canSelectSport(.nba))
        XCTAssertTrue(viewModel.canSelectSport(.nhl))
    }

    // MARK: - Planning State Tests

    func test_isPlanning_defaultsToFalse() {
        let viewModel = TripWizardViewModel()

        XCTAssertFalse(viewModel.isPlanning)
    }

    func test_mustStopLocations_canBeAdded() {
        let viewModel = TripWizardViewModel()
        let location = LocationInput(name: "Chicago, IL", coordinates: nil)

        viewModel.mustStopLocations.append(location)

        XCTAssertEqual(viewModel.mustStopLocations.count, 1)
        XCTAssertEqual(viewModel.mustStopLocations.first?.name, "Chicago, IL")
    }
}