import SwiftUI

struct ScrollPositionPreferenceKey: PreferenceKey {
  typealias Value = ScrollPositionPreference?

  static var defaultValue: Value = nil

  static func reduce(value: inout Value, nextValue: () -> Value) {
    guard let next = nextValue() else { return }

    if let current = value {
      if abs(next.yPosition) < abs(current.yPosition) {
        value = next
      }
    } else {
      value = next
    }
  }
}