Localization/Localization/LocalizationMod.cs

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using GamecraftModdingAPI;
using GamecraftModdingAPI.Commands;
using GamecraftModdingAPI.Utility;
using HarmonyLib;
using IllusionPlugin;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;
using ServiceLayer;

namespace Localization
{
    public class LocalizationMod : IEnhancedPlugin
    {
        private readonly DirectoryInfo _pluginFolder = new DirectoryInfo(Path.Combine("Plugins", "Localization"));
        private Dictionary<string, string> _origStrings;

        public override void OnApplicationStart()
        {
            Main.Init();
            if (!_pluginFolder.Exists)
                _pluginFolder.Create();
            string settingsPath = Path.Combine(_pluginFolder.FullName, "settings.json");
            JObject settings;
            if (File.Exists(settingsPath))
            {
                try
                {
                    using (var stream = new JsonTextReader(File.OpenText(settingsPath)))
                        settings = JObject.Load(stream);
                    string lang = (string) (settings["lang"] ?? (settings["lang"] = "en"));
                    lang = lang.ToLower();
                    if (lang != "en")
                        LoadTranslation(lang);
                }
                catch (Exception e)
                {
                    Logging.LogError(e);
                    settings = new JObject();
                }
            }
            else
                settings = new JObject();

            CommandBuilder.Builder("SetLanguage", "Sets the game's language")
                .Action<string>(lang =>
                {
                    lang = lang.ToLower();
                    settings["lang"] = lang;
                    using (var stream = new JsonTextWriter(new StreamWriter(File.OpenWrite(settingsPath))))
                        settings.WriteTo(stream);
                    LoadTranslation(lang);

                }).Build();
            CommandBuilder.Builder("ListLanguages", "Lists available languages")
                .Action(() =>
                {
                    Logging.CommandLog(new[] {"en"}.Concat(_pluginFolder.EnumerateFiles()
                            .Where(file => file.Extension == ".json" && file.Name.Length < 8)
                            .Select(file => file.Name.Replace(file.Extension, ""))).Distinct()
                        .Aggregate((a, b) => a + ", " + b));
                }).Build();
            CommandBuilder.Builder("DumpLangStrings", "Dumps the current strings. Set language to en-us first.")
                .Action(() =>
                {
                    File.WriteAllText(Path.Combine(_pluginFolder.FullName, "dumped.json"),
                        JsonConvert.SerializeObject(_origStrings));
                }).Build();
        }

        public override void OnApplicationQuit()
        {
            Main.Shutdown();
        }

        private void LoadTranslation(string lang)
        {
            Logging.CommandLog("Loading translation for " + lang + "...");
            LoadOriginalStrings();
            string langPath = Path.Combine(_pluginFolder.FullName, lang + ".json");
            if (!File.Exists(langPath))
            {
                if (lang == "en")
                {
                    AccessTools.Method(typeof(LocalizationService), "Init").Invoke(null, new object[0]);
                    _origStrings = null; //Reset as the object changed
                    LoadOriginalStrings();
                    Logging.CommandLog("Strings reset to default. (" + _origStrings.Count + " strings in total)");
                    return;
                }
                Logging.CommandLogError("Could not find json file!");
                return;
            }

            var strings = JsonConvert.DeserializeObject<Dictionary<string, string>>(File.ReadAllText(langPath));
            foreach (var kv in strings)
            {
                if (!_origStrings.Remove(kv.Key))
                    Logging.CommandLogWarning(kv.Key + " wasn't in the original file.");
                _origStrings.Add(kv.Key, kv.Value);
            }

            Logging.CommandLog("Updated " + strings.Count + " strings (" + _origStrings.Count + " strings in total)");
        }

        private void LoadOriginalStrings()
        {
            if (_origStrings != null) return;
            _origStrings =
                (Dictionary<string, string>) AccessTools.Field(typeof(LocalizationService), "LocalizedStrings")
                    .GetValue(null);
        }

        public override string Name { get; } = "LocalizationMod";
        public override string Version { get; } = "1.0.0";
    }
}