using System;
using System.IO;
using System.Text;
using DCIT.Core.Models;
using Newtonsoft.Json;

namespace DCIT.Core.Services
{
    public class ConfigurationService
    {
        private readonly string _configPath;

        public ConfigurationService(string startupDirectory)
        {
            _configPath = Path.Combine(startupDirectory, "config.json");
        }

        public string ConfigPath
        {
            get { return _configPath; }
        }

        public ConfigurationLoadResult Load()
        {
            if (!File.Exists(_configPath))
            {
                return new ConfigurationLoadResult
                {
                    Config = CreateDefault(),
                    IsMissing = true,
                };
            }

            try
            {
                var content = File.ReadAllText(_configPath, Encoding.UTF8);
                var config = JsonConvert.DeserializeObject<AppConfig>(content) ?? CreateDefault();
                return new ConfigurationLoadResult
                {
                    Config = config,
                };
            }
            catch (Exception ex)
            {
                return new ConfigurationLoadResult
                {
                    Config = CreateDefault(),
                    IsCorrupted = true,
                    ErrorMessage = ex.Message,
                };
            }
        }

        public void Save(AppConfig config)
        {
            config.SavedAt = DateTime.Now;
            var content = JsonConvert.SerializeObject(config, Formatting.Indented);
            File.WriteAllText(_configPath, content, new UTF8Encoding(false));
        }

        public AppConfig CreateDefault()
        {
            return new AppConfig();
        }
    }
}