import XCTest

/// Verifies that a system exposes its voltage-drop budget and that picking a tighter
/// target sticks, which is what drives cable sizing for that system.
final class SystemVoltageDropTargetUITests: XCTestCase {

    override func setUpWithError() throws {
        try super.setUpWithError()
        continueAfterFailure = false
        XCUIDevice.shared.orientation = .portrait
    }

    @MainActor
    func testVoltageDropBudgetIsSelectableInSystemEditor() throws {
        let app = launch(arguments: ["--uitest-reset-data", "--uitest-sample-data"])

        openFirstSystem(in: app)

        let systemTitle = app.buttons["system-title-button"]
        XCTAssertTrue(systemTitle.waitForExistence(timeout: 15))
        systemTitle.tap()

        let picker = app.segmentedControls["system-voltage-drop-picker"]
        XCTAssertTrue(picker.waitForExistence(timeout: 15), "System editor must offer a voltage drop budget")

        let standard = picker.buttons["5 %"]
        XCTAssertTrue(standard.waitForExistence(timeout: 5))
        XCTAssertTrue(standard.isSelected, "New systems start at the 5 % default")

        let critical = picker.buttons["3 %"]
        XCTAssertTrue(critical.exists)
        critical.tap()
        XCTAssertTrue(critical.isSelected, "Picking 3 % must stick")
    }

    // MARK: - Helpers

    private func launch(arguments: [String]) -> XCUIApplication {
        let app = XCUIApplication()
        app.launchArguments = arguments
        app.launch()
        return app
    }

    private func openFirstSystem(in app: XCUIApplication) {
        let list: XCUIElement
        if app.collectionViews["systems-list"].waitForExistence(timeout: 15) {
            list = app.collectionViews["systems-list"]
        } else {
            list = app.collectionViews.firstMatch
        }
        XCTAssertTrue(list.waitForExistence(timeout: 15))

        let firstCell = list.cells.element(boundBy: 0)
        XCTAssertTrue(firstCell.waitForExistence(timeout: 10))

        let cellButton = firstCell.buttons.firstMatch
        if cellButton.exists {
            cellButton.tap()
        } else {
            firstCell.coordinate(withNormalizedOffset: CGVector(dx: 0.5, dy: 0.5)).tap()
        }
    }
}