btcpayserver/BTCPayServer/Services/LanguageService.cs

using System.Collections.Generic;
using System.IO;
using System.Linq;
using Microsoft.AspNetCore.Hosting.Internal;
using Microsoft.Extensions.Hosting;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;
using Newtonsoft.Json.Serialization;

namespace BTCPayServer.Services
{
    public class Language
    {
        public Language(string code, string displayName)
        {
            DisplayName = displayName;
            Code = code;
        }

        [JsonProperty("code")]
        public string Code { get; set; }
        [JsonProperty("currentLanguage")]
        public string DisplayName { get; set; }
    }

    public class LanguageService
    {
        private readonly Language[] _languages;

        public LanguageService(IHostingEnvironment environment)
        {
            var path = (environment as HostingEnvironment)?.WebRootPath;
            if (string.IsNullOrEmpty(path))
            {
                //test environment
                path = Path.Combine(TryGetSolutionDirectoryInfo().FullName,"BTCPayServer", "wwwroot");
            }
            path = Path.Combine(path, "locales");
            var files = Directory.GetFiles(path, "*.json");
            var result = new List<Language>();
            foreach (var file in files)
            {
                using (var stream = new StreamReader(file))
                {
                    var json = stream.ReadToEnd();
                    result.Add(JObject.Parse(json).ToObject<Language>());
                }
            }

            _languages = result.ToArray();
        }

        public static DirectoryInfo TryGetSolutionDirectoryInfo(string currentPath = null)
        {
            var directory = new DirectoryInfo(
                currentPath ?? Directory.GetCurrentDirectory());
            while (directory != null && !directory.GetFiles("*.sln").Any())
            {
                directory = directory.Parent;
            }
            return directory;
        }
        public Language[] GetLanguages()
        {
            return _languages;
        }
    }
}