import Foundation

struct MyPageNoticeRoller {
    private var items: [NoticeItem] = []
    private(set) var index = 0

    var current: NoticeItem? {
        items.isEmpty ? nil : items[index]
    }

    mutating func update(_ items: [NoticeItem]) {
        guard self.items != items else { return }
        self.items = items
        index = 0
    }

    mutating func advance() {
        guard items.count > 1 else { return }
        index = (index + 1) % items.count
    }

    func shouldRoll(isVisible: Bool, isActive: Bool) -> Bool {
        items.count > 1 && isVisible && isActive
    }
}