import XCTest

final class SettingsEffectTests: XCTestCase {
    private let app = XCUIApplication()

    override func setUpWithError() throws {
        continueAfterFailure = false
    }

    func testFontSizeChangeUpdatesContent() throws {
        app.launchAndOpenSampleBook()
        app.waitForReader(timeout: 12)
        app.waitForDemoReaderState(timeout: 5, description: "page exists") { $0.page != nil }

        app.showReaderChromeIfNeeded()
        XCTAssertTrue(app.buttons[IDs.readerSettings].waitForExistence(timeout: 3), "设置按钮不存在")
        app.buttons[IDs.readerSettings].tap()

        XCTAssertTrue(app.waitForSettingsPanel(), "设置面板未出现")
        XCTAssertTrue(app.increaseSettingsFontSize(), "字号滑块不存在")

        XCTAssertTrue(app.buttons[IDs.settingsDone].waitForExistence(timeout: 3), "完成按钮不存在")
        app.buttons[IDs.settingsDone].tap()

        app.waitForDemoReaderState(timeout: 8, description: "reader=opened") { $0.isOpened }
    }

    func testThemeSwitchChangesBackground() throws {
        app.launchAndOpenSampleBook()
        app.waitForReader(timeout: 12)

        app.showReaderChromeIfNeeded()
        app.buttons[IDs.readerSettings].tap()
        XCTAssertTrue(app.waitForSettingsPanel(), "设置面板未出现")

        let darkThemeButton = app.buttons[IDs.settingsTheme(5)]
        if darkThemeButton.waitForExistence(timeout: 3) { darkThemeButton.tap() }

        app.buttons[IDs.settingsDone].tap()

        let contentView = app.otherElements[IDs.readerContentView]
        XCTAssertTrue(contentView.waitForExistence(timeout: 5), "主题切换后内容区应存在")
    }

    func testLineHeightChangeUpdatesContent() throws {
        app.launchAndOpenSampleBook()
        app.waitForReader(timeout: 12)

        app.showReaderChromeIfNeeded()
        app.buttons[IDs.readerSettings].tap()
        XCTAssertTrue(app.waitForSettingsPanel())

        app.selectSettingsPillOption(pillIdentifier: IDs.settingsLineHeight, optionTitle: "标准")

        app.buttons[IDs.settingsDone].tap()
        app.waitForDemoReaderState(timeout: 8, description: "reader=opened") { $0.isOpened }
    }

    func testDisplayTypeChangeRePaginates() throws {
        app.launchAndOpenSampleBook(displayType: "horizontalscroll")
        app.waitForReader(timeout: 12)
        app.waitForDemoReaderState(timeout: 5, description: "display=horizontalScroll") { $0.display == "horizontalScroll" }

        app.showReaderChromeIfNeeded()
        app.buttons[IDs.readerSettings].tap()
        XCTAssertTrue(app.waitForSettingsPanel())

        app.selectSettingsPillOption(pillIdentifier: IDs.settingsDisplayType, optionTitle: "仿真")

        app.buttons[IDs.settingsDone].tap()
        app.waitForDemoReaderState(timeout: 8, description: "display changed") { $0.display != nil }
    }

    func testDefaultBodyPaginationDoesNotEnableWidowOrphanCompaction() throws {
        app.launchAndOpenSampleBook()
        app.waitForReader(timeout: 12)

        let state = app.waitForDemoReaderState(timeout: 8, description: "默认正文分页策略") { state in
            state.avoidWidows != nil && state.avoidOrphans != nil
        }

        XCTAssertEqual(state.avoidWidows, 0, "默认正文分页不应启用 widow compaction，避免页尾明显留白")
        XCTAssertEqual(state.avoidOrphans, 0, "默认正文分页不应启用 orphan compaction，避免提前换页")
    }

    func testSettingsPersistAfterReopen() throws {
        app.launchAndOpenSampleBook()
        app.waitForReader(timeout: 12)

        app.showReaderChromeIfNeeded()
        app.buttons[IDs.readerSettings].tap()

        XCTAssertTrue(app.sliders[IDs.settingsFontSize].waitForExistence(timeout: 5))
        let fontValueLabel = app.staticTexts[IDs.settingsFontValue]
        XCTAssertTrue(fontValueLabel.waitForExistence(timeout: 3))
        let originalFontValue = fontValueLabel.label

        XCTAssertTrue(app.increaseSettingsFontSize(), "字号滑块应存在")
        let newFontValue = fontValueLabel.label
        XCTAssertNotEqual(newFontValue, originalFontValue, "增大字号后 label 应变化")

        app.buttons[IDs.settingsDone].tap()
        app.buttons[IDs.readerBack].tap()

        // 必须保留状态：默认的 resetsReaderState 会清掉刚存下的设置，
        // 那样这个用例永远测不到持久化
        app.launchAndOpenSampleBook(resetsReaderState: false)
        app.waitForReader(timeout: 12)

        app.showReaderChromeIfNeeded()
        app.buttons[IDs.readerSettings].tap()

        let persistedFontValue = app.staticTexts[IDs.settingsFontValue]
        if persistedFontValue.waitForExistence(timeout: 5) {
            XCTAssertEqual(persistedFontValue.label, newFontValue, "重新打开后字号应持久化为之前的值")
        }

        app.buttons[IDs.settingsDone].tap()
    }

    func testThemeSelectionPersistsAfterReopen() throws {
        app.launchAndOpenSampleBook(resetsReaderState: true)
        app.waitForReader(timeout: 12)

        app.showReaderChromeIfNeeded()
        app.buttons[IDs.readerSettings].tap()

        let darkThemeButton = app.buttons[IDs.settingsTheme(5)]
        XCTAssertTrue(darkThemeButton.waitForExistence(timeout: 5))
        darkThemeButton.tap()
        XCTAssertEqual(darkThemeButton.value as? String, "selected", "切换主题后当前主题按钮应为选中态")
        app.buttons[IDs.settingsDone].tap()

        app.showReaderChromeIfNeeded()
        app.buttons[IDs.readerBack].tap()

        app.launchAndOpenSampleBook(resetsReaderState: false)
        app.waitForReader(timeout: 12)
        app.showReaderChromeIfNeeded()
        app.buttons[IDs.readerSettings].tap()

        let reopenedDarkThemeButton = app.buttons[IDs.settingsTheme(5)]
        XCTAssertTrue(reopenedDarkThemeButton.waitForExistence(timeout: 5))
        XCTAssertEqual(reopenedDarkThemeButton.value as? String, "selected", "主题应在重启后保持选中")
        app.buttons[IDs.settingsDone].tap()
    }

    func testFontChoiceChangePersistsAfterReopen() throws {
        app.launchAndOpenSampleBook(resetsReaderState: true)
        app.waitForReader(timeout: 12)

        app.showReaderChromeIfNeeded()
        app.buttons[IDs.readerSettings].tap()

        let fontChoiceControl = app.buttons[IDs.settingsFontChoice]
        XCTAssertTrue(fontChoiceControl.waitForExistence(timeout: 5))
        XCTAssertTrue(
            app.selectSettingsPillOption(pillIdentifier: IDs.settingsFontChoice, optionTitle: "宋体"),
            "字体应可切换到宋体"
        )
        XCTAssertEqual(fontChoiceControl.value as? String, "宋体", "切换字体后当前字体值应更新")
        app.buttons[IDs.settingsDone].tap()

        app.showReaderChromeIfNeeded()
        app.buttons[IDs.readerBack].tap()

        app.launchAndOpenSampleBook(resetsReaderState: false)
        app.waitForReader(timeout: 12)
        app.showReaderChromeIfNeeded()
        app.buttons[IDs.readerSettings].tap()

        let reopenedFontChoiceControl = app.buttons[IDs.settingsFontChoice]
        XCTAssertTrue(reopenedFontChoiceControl.waitForExistence(timeout: 5))
        XCTAssertEqual(reopenedFontChoiceControl.value as? String, "宋体", "字体选择应在重启后保持")
        app.buttons[IDs.settingsDone].tap()
    }
}