import XCTest

/// Verifies that the Overview export/share menu is only available once the
/// system actually contains something worth exporting.
final class SystemExportButtonUITests: XCTestCase {

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

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

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

        let shareButton = app.buttons["system-overview-share-button"]
        XCTAssertTrue(shareButton.waitForExistence(timeout: 15))
        XCTAssertFalse(
            shareButton.isEnabled,
            "Export must stay disabled while the system has no loads, batteries or chargers"
        )
    }

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

        openFirstSystem(in: app)

        let shareButton = app.buttons["system-overview-share-button"]
        XCTAssertTrue(shareButton.waitForExistence(timeout: 15))
        XCTAssertTrue(
            shareButton.isEnabled,
            "Export must be available for a system that has components"
        )
    }

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

        openFirstSystem(in: app)

        let shareButton = app.buttons["system-overview-share-button"]
        XCTAssertTrue(shareButton.waitForExistence(timeout: 15))
        shareButton.tap()

        let reportItem = app.buttons.matching(
            NSPredicate(format: "label CONTAINS[c] 'PDF'")
        ).firstMatch
        XCTAssertTrue(reportItem.waitForExistence(timeout: 10))
        reportItem.tap()

        // Quick Look lives in its own navigation stack; the Done button proves
        // the navigation bar exists, the share item proves the file can leave
        // the preview.
        let doneButton = app.buttons["quick-look-done-button"]
        XCTAssertTrue(
            doneButton.waitForExistence(timeout: 60),
            "Quick Look preview must be embedded in a navigation bar"
        )

        // Scope the action lookup to the preview's own navigation bar so the
        // Overview share button underneath can never satisfy it.
        let previewBar = app.navigationBars.containing(
            .button,
            identifier: "quick-look-done-button"
        ).firstMatch
        XCTAssertTrue(previewBar.waitForExistence(timeout: 10))

        let actionButtons = previewBar.buttons.allElementsBoundByIndex
            .filter { $0.identifier != "quick-look-done-button" }
        XCTAssertFalse(
            actionButtons.isEmpty,
            "Quick Look preview must offer an action button to share or open the file"
        )

        doneButton.tap()
        XCTAssertTrue(shareButton.waitForExistence(timeout: 10))
    }

    // 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()
        }
    }
}