//
//  SnapshotGalleryTests.swift
//  HoneyDueTests
//
//  P3 — iOS parity gallery. Records baseline PNGs for primary SwiftUI screens
//  across {empty-state} × {light, dark}. Complements the Android Roborazzi
//  gallery (P2); both platforms consume the same Kotlin FixtureDataManager
//  fixtures (P1), so any layout divergence between Android + iOS renders of
//  the same screen is a real parity bug — not a test-data mismatch.
//
//  Current state coverage
//  ----------------------
//  * Empty (signed-in user with no residences / tasks / docs / contractors)
//    is captured for every screen below via the default
//    `DataManagerObservable.shared`, which has no data loaded when tests run
//    because no login has occurred in the test host.
//  * Populated state is BLOCKED on a follow-up ViewModel-injection refactor:
//    current SwiftUI screens instantiate their ViewModels via
//    `@StateObject private var viewModel = FooViewModel()`, and those
//    ViewModels read directly from `DataManagerObservable.shared` rather
//    than an injected `IDataManager`. Swapping the singleton is unsafe in
//    parallel tests. Follow-up PR: add an optional `dataManager:` init param
//    to each `*ViewModel.swift` and thread it from here via
//    `.environment(\.dataManager, ...)`.
//
//  Recording goldens
//  -----------------
//  Preferred: `make record-snapshots` (or `./scripts/record_snapshots.sh
//  --ios-only`). The script exports `SNAPSHOT_TESTING_RECORD=1` in the
//  xcodebuild env, deletes the old `__Snapshots__/SnapshotGalleryTests`
//  directory, runs the target, then invokes the shared PNG optimizer.
//
//  Manual override: set the `SNAPSHOT_TESTING_RECORD` env var to `1` in
//  the Xcode scheme's Test action (Edit Scheme → Test → Arguments →
//  Environment Variables) and re-run the test target. CI fails the
//  build if a screen diverges from its golden by more than the
//  precision threshold.
//
//  Rendering scale
//  ---------------
//  We force `displayScale: 2.0` on every snapshot. The iPhone 15 /
//  iPhone 13 simulators default to the device's native 3x, which on a
//  full-screen gradient-heavy SwiftUI view produced 800–1000 KB PNGs
//  per image. @2x halves the linear dimensions (2.25x fewer pixels) and
//  is still plenty to catch layout regressions. Combined with
//  `scripts/optimize_goldens.sh` (zopflipng / pngcrush) this keeps us
//  under the 150 KB per-image budget enforced by CI.
//

@preconcurrency import SnapshotTesting
import SwiftUI
import XCTest
import ComposeApp
@testable import honeyDue

@MainActor
final class SnapshotGalleryTests: XCTestCase {

    // Record mode is driven by the `SNAPSHOT_TESTING_RECORD` env var so
    // `scripts/record_snapshots.sh` can flip it without mutating this file.
    // When the var is unset/empty we only write missing goldens (`.missing`)
    // so local dev runs never silently overwrite committed PNGs.
    private static var recordMode: SnapshotTestingConfiguration.Record {
        let env = ProcessInfo.processInfo.environment["SNAPSHOT_TESTING_RECORD"] ?? ""
        return (env == "1" || env.lowercased() == "true") ? .all : .missing
    }

    override func invokeTest() {
        withSnapshotTesting(record: Self.recordMode) {
            super.invokeTest()
        }
    }

    // MARK: - Helpers

    /// Snapshot a SwiftUI view in both light + dark modes under a stable
    /// iPhone 13 layout. The screen is wrapped in a `NavigationStack` so that
    /// any `.navigationTitle`/`.toolbar` chrome the view declares is rendered
    /// identically to how it ships to users.
    // Most HoneyDue screens animate on appear (OrganicBlobShape gradients,
    // subtle pulses, TextField focus rings). A tiny amount of pixel drift
    // between runs is expected; the goal of parity snapshots is to catch
    // *structural* regressions, not single-pixel anti-alias differences.
    // These thresholds were tuned so that a second run against goldens
    // recorded on the first run passes green.
    private static let pixelPrecision: Float = 0.97
    private static let perceptualPrecision: Float = 0.95

    /// Force @2x rendering regardless of the simulator device's native
    /// `displayScale`. See the class-level "Rendering scale" comment for
    /// rationale. 2.0 keeps PNGs under the size budget without sacrificing
    /// the structural detail our parity gallery cares about.
    private static let forcedDisplayScale: CGFloat = 2.0

    private func snap<V: View>(
        _ name: String,
        file: StaticString = #filePath,
        testName: String = #function,
        line: UInt = #line,
        @ViewBuilder content: () -> V
    ) {
        let view = content()
            .environmentObject(ThemeManager.shared)
            .environment(\.dataManager, DataManagerObservable.shared)

        assertSnapshot(
            of: view.environment(\.colorScheme, .light),
            as: .image(
                precision: Self.pixelPrecision,
                perceptualPrecision: Self.perceptualPrecision,
                layout: .device(config: .iPhone13),
                traits: .init(traitsFrom: [
                    UITraitCollection(userInterfaceStyle: .light),
                    UITraitCollection(displayScale: Self.forcedDisplayScale),
                ])
            ),
            named: "\(name)_light",
            file: file,
            testName: testName,
            line: line
        )
        assertSnapshot(
            of: view.environment(\.colorScheme, .dark),
            as: .image(
                precision: Self.pixelPrecision,
                perceptualPrecision: Self.perceptualPrecision,
                layout: .device(config: .iPhone13),
                traits: .init(traitsFrom: [
                    UITraitCollection(userInterfaceStyle: .dark),
                    UITraitCollection(displayScale: Self.forcedDisplayScale),
                ])
            ),
            named: "\(name)_dark",
            file: file,
            testName: testName,
            line: line
        )
    }

    // MARK: - Auth flow

    func test_login_empty() {
        snap("login_empty") {
            LoginView(resetToken: .constant(nil), onLoginSuccess: nil)
        }
    }

    func test_register_empty() {
        snap("register_empty") {
            RegisterView(isPresented: .constant(true), onVerified: nil)
        }
    }

    func test_verify_email_empty() {
        snap("verify_email_empty") {
            VerifyEmailView(onVerifySuccess: {}, onLogout: {})
        }
    }

    func test_forgot_password_empty() {
        let vm = PasswordResetViewModel()
        snap("forgot_password_empty") {
            NavigationStack { ForgotPasswordView(viewModel: vm) }
        }
    }

    func test_verify_reset_code_empty() {
        let vm = PasswordResetViewModel()
        vm.email = "user@example.com"
        vm.currentStep = .verifyCode
        snap("verify_reset_code_empty") {
            NavigationStack { VerifyResetCodeView(viewModel: vm) }
        }
    }

    func test_reset_password_empty() {
        let vm = PasswordResetViewModel()
        vm.currentStep = .resetPassword
        snap("reset_password_empty") {
            NavigationStack { ResetPasswordView(viewModel: vm, onSuccess: {}) }
        }
    }

    // MARK: - Onboarding

    func test_onboarding_welcome_empty() {
        snap("onboarding_welcome_empty") {
            OnboardingWelcomeView(onStartFresh: {}, onJoinExisting: {}, onLogin: {})
        }
    }

    func test_onboarding_value_props_empty() {
        snap("onboarding_value_props_empty") {
            OnboardingValuePropsView(onContinue: {}, onSkip: {}, onBack: {})
        }
    }

    func test_onboarding_create_account_empty() {
        snap("onboarding_create_account_empty") {
            OnboardingCreateAccountView(onAccountCreated: { _ in }, onBack: {})
        }
    }

    func test_onboarding_verify_email_empty() {
        snap("onboarding_verify_email_empty") {
            OnboardingVerifyEmailView(onVerified: {}, onLogout: {})
        }
    }

    func test_onboarding_name_residence_empty() {
        snap("onboarding_name_residence_empty") {
            StatefulPreviewWrapper("") { binding in
                OnboardingNameResidenceView(
                    residenceName: binding,
                    onContinue: {},
                    onBack: {}
                )
            }
        }
    }

    func test_onboarding_join_residence_empty() {
        snap("onboarding_join_residence_empty") {
            OnboardingJoinResidenceView(onJoined: {}, onSkip: {})
        }
    }

    func test_onboarding_subscription_empty() {
        snap("onboarding_subscription_empty") {
            OnboardingSubscriptionView(onSubscribe: {}, onSkip: {})
        }
    }

    func test_onboarding_first_task_empty() {
        snap("onboarding_first_task_empty") {
            OnboardingFirstTaskView(
                residenceName: "My House",
                onTaskAdded: {},
                onSkip: {}
            )
        }
    }

    // MARK: - Residence

    func test_residences_list_empty() {
        snap("residences_list_empty") {
            NavigationStack { ResidencesListView() }
        }
    }

    func test_add_residence_empty() {
        snap("add_residence_empty") {
            AddResidenceView(isPresented: .constant(true), onResidenceCreated: nil)
        }
    }

    func test_join_residence_empty() {
        snap("join_residence_empty") {
            JoinResidenceView(onJoined: {})
        }
    }

    // MARK: - Tasks

    func test_all_tasks_empty() {
        snap("all_tasks_empty") {
            NavigationStack { AllTasksView() }
        }
    }

    func test_add_task_empty() {
        snap("add_task_empty") {
            AddTaskView(residenceId: 1, isPresented: .constant(true))
        }
    }

    func test_add_task_with_residence_empty() {
        snap("add_task_with_residence_empty") {
            AddTaskWithResidenceView(isPresented: .constant(true), residences: [])
        }
    }

    func test_task_suggestions_empty() {
        snap("task_suggestions_empty") {
            TaskSuggestionsView(
                suggestions: [],
                onSelect: { _ in }
            )
        }
    }

    func test_task_templates_browser_empty() {
        snap("task_templates_browser_empty") {
            NavigationStack { TaskTemplatesBrowserView(onSelect: { _ in }) }
        }
    }

    // MARK: - Contractor

    func test_contractors_list_empty() {
        snap("contractors_list_empty") {
            NavigationStack { ContractorsListView() }
        }
    }

    // MARK: - Documents

    func test_documents_warranties_empty() {
        snap("documents_warranties_empty") {
            NavigationStack { DocumentsWarrantiesView(residenceId: nil) }
        }
    }

    // MARK: - Profile

    func test_profile_tab_empty() {
        snap("profile_tab_empty") {
            NavigationStack { ProfileTabView() }
        }
    }

    func test_profile_edit_empty() {
        snap("profile_edit_empty") {
            NavigationStack { ProfileView() }
        }
    }

    func test_notification_preferences_empty() {
        snap("notification_preferences_empty") {
            NavigationStack { NotificationPreferencesView() }
        }
    }

    func test_theme_selection_empty() {
        snap("theme_selection_empty") {
            NavigationStack { ThemeSelectionView() }
        }
    }

    // MARK: - Subscription

    func test_feature_comparison_empty() {
        snap("feature_comparison_empty") {
            FeatureComparisonView(isPresented: .constant(true))
        }
    }

    // NOTE: UpgradeFeatureView is intentionally excluded from the parity
    // gallery. It reads `SubscriptionCacheWrapper.shared` and
    // `StoreKitManager.shared` on appear, both of which populate
    // asynchronously in a way that isn't deterministic inside a snapshot
    // test. Follow-up PR should add a fixture-friendly init override
    // mirroring the `dataManager:` pattern.
}

// MARK: - StatefulPreviewWrapper

/// Lets us hand a view a `@Binding` backed by a local `@State` so that
/// views which mutate bindings (e.g. `OnboardingNameResidenceView`) render
/// correctly inside a snapshot test — which has no surrounding state host.
private struct StatefulPreviewWrapper<Value, Content: View>: View {
    @State private var value: Value
    let content: (Binding<Value>) -> Content

    init(_ initial: Value, @ViewBuilder content: @escaping (Binding<Value>) -> Content) {
        _value = State(initialValue: initial)
        self.content = content
    }

    var body: some View {
        content($value)
    }
}