Localized Text for SwiftUI

LocalizedText.swift

import Foundation
import SwiftUI

protocol TextLocalizable {
    var `default`: String { get }
    var enUS: String { get }
    var jaJP: String { get }
    // TODO: Implement others of Locale.availableIdentifiers
}

extension TextLocalizable {
    var enUS: String {
        `default`
    }

    var jaJP: String {
        `default`
    }
}

struct LocalizedText<T: TextLocalizable>: View {
    @Environment(\.locale) private var locale
    private let t: T

    init(_ t: T) {
        self.t = t
    }

    var body: some View {
        switch locale.identifier {
        case "en_US":
            Text(verbatim: t.enUS)
        case "ja_JP":
            Text(verbatim: t.jaJP)
        default:
            Text(verbatim: t.default)
        }
    }
}

struct ContentView: View {
    enum LocalizedTextValue: TextLocalizable {
        case hello
        case name(String)

        var `default`: String {
            enUS
        }

        var enUS: String {
            switch self {
            case .hello:
                return "Hello"
            case .name(let name):
                return "\(name)-san"
            }
        }

        var jaJP: String {
            switch self {
            case .hello:
                return "こんにちは"
            case .name(let name):
                return "\(name)さん"
            }
        }
    }

    var body: some View {
        VStack {
            LocalizedText(LocalizedTextValue.hello)
            LocalizedText(LocalizedTextValue.name("yutailang0119"))
        }
    }
}