MenuPicker.swift

//
//  MenuPicker.swift
//  BitRemote
//
//  Created by 荒木辰造 on R 5/03/12.
//

import SwiftUI

struct MenuPicker<Items: RandomAccessCollection, Element: Equatable, ID: Hashable, MenuLabel: View>: View
where Element == Items.Element {
    let items: Items
    let id: KeyPath<Element, ID>
    let title: KeyPath<Element, String>
    @Binding var selectedItem: Element?
    @ViewBuilder var label: (Element?) -> MenuLabel

    var body: some View {
        Menu(
            content: {
                ForEach(items, id: id) { item in
                    Button {
                        selectedItem = item
                    } label: {
                        if selectedItem == item {
                            Label(item[keyPath: title], systemImage: "checkmark")
                        } else {
                            Text(item[keyPath: title])
                        }
                    }
                }
            },
            label: {
                label(selectedItem)
            }
        )
        .menuOrder(.fixed)
    }
}

extension MenuPicker where Element: Identifiable, ID == Element.ID {
    init(
        items: Items,
        title: KeyPath<Element, String>,
        selectedItem: Binding<Element?>,
        label: @escaping (Element?) -> MenuLabel
    ) {
        self.items = items
        self.id = \Element.id
        self.title = title
        self._selectedItem = selectedItem
        self.label = label
    }
}