import XCTest

/// UI tests for authentication flows: login, signup, forgot password, toggle.
final class AuthFlowUITests: UITestBase {
    /// Test class overrides scenario to unauthenticated
    override class var scenario: UITestScenario { .unauthenticated }

    // MARK: - Helpers

    /// Relaunch the app with a specific scenario and reassign self.app
    private func relaunch(scenario: UITestScenario) {
        app.terminate()
        app = XCUIApplication()
        app.launchArguments = ["-UITesting"]
        app.launchEnvironment["UITestScenario"] = scenario.rawValue
        app.launch()
    }

    // MARK: - Launch & Branding

    /// Verify the app launches to the auth screen when unauthenticated
    func testLaunchAppShowsOnboardingScreen() {
        // Verify branding elements are visible
        XCTAssertTrue(text("Kordant").exists, "Brand name should be visible")
        XCTAssertTrue(text("Protect what matters most").exists, "Tagline should be visible")
        XCTAssertTrue(button("Continue with Google").exists, "Google sign-in button should exist")
    }

    // MARK: - Login / Signup Toggle

    /// Verify user can toggle between login and signup forms
    func testToggleBetweenLoginAndSignup() {
        // Should start on login view
        XCTAssertTrue(button("Sign In").exists, "Sign In button should be visible on login form")

        // Tap the toggle link to show signup
        button("Don't have an account? Sign up").tap()
        XCTAssertTrue(button("Create Account").exists, "Create Account button should be visible on signup form")

        // Tap back to login
        button("Already have an account? Sign in").tap()
        XCTAssertTrue(button("Sign In").exists, "Sign In button should be visible after toggling back")
    }

    // MARK: - Login with Valid Credentials

    /// Test successful login navigates to the dashboard
    func testLoginWithValidCredentialsNavigatesToDashboard() {
        // Re-launch with authenticated scenario
        relaunch(scenario: .authenticated)

        // When already authenticated, the app should skip auth and show the main tab view
        XCTAssertTrue(app.tabBars.buttons["Dashboard"].waitForExistence(timeout: 5),
                      "Dashboard tab should be visible when authenticated")
    }

    // MARK: - Login with Invalid Credentials

    /// Test login with invalid credentials shows error state
    func testLoginWithInvalidCredentialsShowsError() {
        // Re-launch with authError scenario
        relaunch(scenario: .authError)

        // In .authError scenario, the mock API will fail
        let emailField = app.textFields["Email"]
        guard emailField.waitForExistence(timeout: 3) else {
            XCTFail("Email field not found")
            return
        }
        emailField.tap()
        emailField.typeText("wrong@email.com")

        let passwordField = app.secureTextFields["Password"]
        passwordField.tap()
        passwordField.typeText("wrongpassword")

        button("Sign In").tap()

        // Should show an error (either as inline text or alert)
        let errorExists = app.staticTexts.containing(
            NSPredicate(format: "label CONTAINS[c] 'error' OR label CONTAINS[c] 'Invalid' OR label CONTAINS[c] 'Unauthorized'")
        ).element.exists
        || app.alerts.element.exists

        XCTAssertTrue(errorExists, "Error should be shown for invalid credentials")
        captureScreen(name: "LoginInvalidCredentials")
    }

    // MARK: - Signup Form Validation

    /// Test signup form shows validation errors for invalid input
    func testSignupFormValidationShowsErrors() {
        // Switch to signup
        let toggleButton = button("Don't have an account? Sign up")
        guard toggleButton.waitForExistence(timeout: 2) else {
            XCTFail("Toggle to signup button not found")
            return
        }
        toggleButton.tap()

        // Wait for signup form to appear
        XCTAssertTrue(button("Create Account").waitForExistence(timeout: 2),
                      "Create Account button should be visible on signup form")

        // Try to submit empty form - tap Create Account with empty fields
        button("Create Account").tap()

        // Should show validation errors
        let errorExists = app.staticTexts.containing(
            NSPredicate(format: "label CONTAINS[c] 'required' OR label CONTAINS[c] 'must'")
        ).element.exists

        XCTAssertTrue(errorExists, "Validation errors should be shown for empty form")
        captureScreen(name: "SignupValidationErrors")
    }

    // MARK: - Forgot Password Flow

    /// Test the forgot password flow shows confirmation
    func testForgotPasswordFlowShowsConfirmation() {
        // Re-launch with forgotPasswordSuccess scenario
        relaunch(scenario: .forgotPasswordSuccess)

        // Tap "Forgot password?" link
        let forgotButton = button("Forgot password?")
        guard forgotButton.waitForExistence(timeout: 3) else {
            XCTFail("Forgot password link not found")
            return
        }
        forgotButton.tap()

        // Forgot password sheet should appear
        let emailField = app.textFields["Email"]
        guard emailField.waitForExistence(timeout: 3) else {
            XCTFail("Email field in forgot password sheet not found")
            return
        }

        emailField.tap()
        emailField.typeText("test@kordant.com")

        button("Send Reset Link").tap()

        // Should see success state
        let successExists = text("Check your email").waitForExistence(timeout: 3)
        XCTAssertTrue(successExists, "Forgot password success state should be shown")
        captureScreen(name: "ForgotPasswordSuccess")
    }

    // MARK: - Authenticated Scenario

    /// Test that the authenticated scenario loads the dashboard
    func testAuthenticatedScenarioLoadsDashboard() {
        relaunch(scenario: .authenticated)

        // Verify we're on the dashboard
        XCTAssertTrue(app.navigationBars["Dashboard"].waitForExistence(timeout: 5),
                      "Dashboard navigation bar should appear after authentication")
    }

    // MARK: - Biometric Prompt

    /// Test auth flow completes successfully (biometric prompt is shown when applicable)
    func testAuthFlowCompletesSuccessfully() {
        relaunch(scenario: .authenticated)

        // Verify we reach the main app with tab bar
        let dashboardTab = app.tabBars.buttons["Dashboard"]
        XCTAssertTrue(dashboardTab.waitForExistence(timeout: 5),
                      "App should show tab bar after authentication")
    }

    // MARK: - Email Field Accessibility

    /// Verify email and password fields are accessible in login form
    func testLoginFormFieldsAreAccessible() {
        // Verify fields exist on the login form
        // With `.unauthenticated` scenario (current), should see login form
        let emailField = app.textFields["Email"]
        XCTAssertTrue(emailField.waitForExistence(timeout: 3),
                      "Email text field should exist on login form")
        XCTAssertTrue(emailField.isEnabled, "Email field should be enabled")

        let passwordField = app.secureTextFields["Password"]
        XCTAssertTrue(passwordField.exists, "Password secure field should exist")
        XCTAssertTrue(passwordField.isEnabled, "Password field should be enabled")
    }
}