using System;
using System.Collections.Generic;
using System.Linq;
using NLog;
using NzbDrone.Common.EnsureThat;
using NzbDrone.Common.EnvironmentInfo;
using NzbDrone.Core.Configuration.Events;
using NzbDrone.Core.MediaFiles;
using NzbDrone.Core.Messaging.Events;

namespace NzbDrone.Core.Configuration
{
    public enum ConfigKey
    {
        DownloadedEpisodesFolder
    }

    public class ConfigService : IConfigService
    {
        private readonly IConfigRepository _repository;
        private readonly IEventAggregator _eventAggregator;
        private readonly Logger _logger;
        private static Dictionary<string, string> _cache;

        public ConfigService(IConfigRepository repository, IEventAggregator eventAggregator, Logger logger)
        {
            _repository = repository;
            _eventAggregator = eventAggregator;
            _logger = logger;
            _cache = new Dictionary<string, string>();
        }

        private Dictionary<string, object> AllWithDefaults()
        {
            var dict = new Dictionary<string, object>(StringComparer.InvariantCultureIgnoreCase);

            var type = GetType();
            var properties = type.GetProperties();

            foreach (var propertyInfo in properties)
            {
                var value = propertyInfo.GetValue(this, null);
                dict.Add(propertyInfo.Name, value);
            }

            return dict;
        }

        public void SaveConfigDictionary(Dictionary<string, object> configValues)
        {
            var allWithDefaults = AllWithDefaults();

            foreach (var configValue in configValues)
            {
                object currentValue;
                allWithDefaults.TryGetValue(configValue.Key, out currentValue);
                if (currentValue == null) continue;

                var equal = configValue.Value.ToString().Equals(currentValue.ToString());

                if (!equal)
                {
                    SetValue(configValue.Key, configValue.Value.ToString());
                }
            }

            _eventAggregator.PublishEvent(new ConfigSavedEvent());
        }

        public bool IsDefined(string key)
        {
            return _repository.Get(key.ToLower()) != null;
        }

        public string DownloadedEpisodesFolder
        {
            get { return GetValue(ConfigKey.DownloadedEpisodesFolder.ToString()); }

            set { SetValue(ConfigKey.DownloadedEpisodesFolder.ToString(), value); }
        }

        public bool AutoUnmonitorPreviouslyDownloadedEpisodes
        {
            get { return GetValueBoolean("AutoUnmonitorPreviouslyDownloadedEpisodes"); }
            set { SetValue("AutoUnmonitorPreviouslyDownloadedEpisodes", value); }
        }

        public int Retention
        {
            get { return GetValueInt("Retention", 0); }
            set { SetValue("Retention", value); }
        }

        public string RecycleBin
        {
            get { return GetValue("RecycleBin", string.Empty); }
            set { SetValue("RecycleBin", value); }
        }

        public int RssSyncInterval
        {
            get { return GetValueInt("RssSyncInterval", 15); }

            set { SetValue("RssSyncInterval", value); }
        }

        public int MinimumAge
        {
            get { return GetValueInt("MinimumAge", 0); }

            set { SetValue("MinimumAge", value); }
        }

        public bool AutoDownloadPropers
        {
            get { return GetValueBoolean("AutoDownloadPropers", true); }

            set { SetValue("AutoDownloadPropers", value); }
        }

        public bool EnableCompletedDownloadHandling
        {
            get { return GetValueBoolean("EnableCompletedDownloadHandling", true); }

            set { SetValue("EnableCompletedDownloadHandling", value); }
        }

        public bool RemoveCompletedDownloads
        {
            get { return GetValueBoolean("RemoveCompletedDownloads", false); }

            set { SetValue("RemoveCompletedDownloads", value); }
        }

        public bool AutoRedownloadFailed
        {
            get { return GetValueBoolean("AutoRedownloadFailed", true); }

            set { SetValue("AutoRedownloadFailed", value); }
        }

        public bool RemoveFailedDownloads
        {
            get { return GetValueBoolean("RemoveFailedDownloads", true); }

            set { SetValue("RemoveFailedDownloads", value); }
        }

        public bool CreateEmptySeriesFolders
        {
            get { return GetValueBoolean("CreateEmptySeriesFolders", false); }

            set { SetValue("CreateEmptySeriesFolders", value); }
        }

        public FileDateType FileDate
        {
            get { return GetValueEnum("FileDate", FileDateType.None); }

            set { SetValue("FileDate", value); }
        }

        public string DownloadClientWorkingFolders
        {
            get { return GetValue("DownloadClientWorkingFolders", "_UNPACK_|_FAILED_"); }
            set { SetValue("DownloadClientWorkingFolders", value); }
        }

        public int DownloadedEpisodesScanInterval
        {
            get { return GetValueInt("DownloadedEpisodesScanInterval", 1); }

            set { SetValue("DownloadedEpisodesScanInterval", value); }
        }

        public int DownloadClientHistoryLimit
        {
            get { return GetValueInt("DownloadClientHistoryLimit", 30); }

            set { SetValue("DownloadClientHistoryLimit", value); }
        }

        public bool SkipFreeSpaceCheckWhenImporting
        {
            get { return GetValueBoolean("SkipFreeSpaceCheckWhenImporting", false); }

            set { SetValue("SkipFreeSpaceCheckWhenImporting", value); }
        }

        public bool CopyUsingHardlinks
        {
            get { return GetValueBoolean("CopyUsingHardlinks", true); }

            set { SetValue("CopyUsingHardlinks", value); }
        }

        public bool EnableMediaInfo
        {
            get { return GetValueBoolean("EnableMediaInfo", true); }

            set { SetValue("EnableMediaInfo", value); }
        }

        public bool SetPermissionsLinux
        {
            get { return GetValueBoolean("SetPermissionsLinux", false); }

            set { SetValue("SetPermissionsLinux", value); }
        }

        public string FileChmod
        {
            get { return GetValue("FileChmod", "0644"); }

            set { SetValue("FileChmod", value); }
        }

        public string FolderChmod
        {
            get { return GetValue("FolderChmod", "0755"); }

            set { SetValue("FolderChmod", value); }
        }

        public string ChownUser
        {
            get { return GetValue("ChownUser", ""); }

            set { SetValue("ChownUser", value); }
        }

        public string ChownGroup
        {
            get { return GetValue("ChownGroup", ""); }

            set { SetValue("ChownGroup", value); }
        }

        public int FirstDayOfWeek
        {
            get { return GetValueInt("FirstDayOfWeek", (int)OsInfo.FirstDayOfWeek); }

            set { SetValue("FirstDayOfWeek", value); }
        }

        public string CalendarWeekColumnHeader
        {
            get { return GetValue("CalendarWeekColumnHeader", "ddd M/D"); }

            set { SetValue("CalendarWeekColumnHeader", value); }
        }

        public string ShortDateFormat
        {
            get { return GetValue("ShortDateFormat", "MMM D YYYY"); }

            set { SetValue("ShortDateFormat", value); }
        }

        public string LongDateFormat
        {
            get { return GetValue("LongDateFormat", "dddd, MMMM D YYYY"); }

            set { SetValue("LongDateFormat", value); }
        }

        public string TimeFormat
        {
            get { return GetValue("TimeFormat", "h(:mm)a"); }

            set { SetValue("TimeFormat", value); }
        }

        public bool ShowRelativeDates
        {
            get { return GetValueBoolean("ShowRelativeDates", true); }

            set { SetValue("ShowRelativeDates", value); }
        }

        public bool EnableColorImpairedMode
        {
            get { return GetValueBoolean("EnableColorImpairedMode", false); }

            set { SetValue("EnableColorImpairedMode", value); }
        }

        public bool CleanupMetadataImages
        {
            get { return GetValueBoolean("CleanupMetadataImages", true); }

            set { SetValue("CleanupMetadataImages", value); }
        }

        public string RijndaelPassphrase
        {
            get { return GetValue("RijndaelPassphrase", Guid.NewGuid().ToString(), true); }
        }

        public string HmacPassphrase
        {
            get { return GetValue("HmacPassphrase", Guid.NewGuid().ToString(), true); }
        }

        public string RijndaelSalt
        {
            get { return GetValue("RijndaelSalt", Guid.NewGuid().ToString(), true); }
        }

        public string HmacSalt
        {
            get { return GetValue("HmacSalt", Guid.NewGuid().ToString(), true); }
        }

        private string GetValue(string key)
        {
            return GetValue(key, string.Empty);
        }

        private bool GetValueBoolean(string key, bool defaultValue = false)
        {
            return Convert.ToBoolean(GetValue(key, defaultValue));
        }

        private int GetValueInt(string key, int defaultValue = 0)
        {
            return Convert.ToInt32(GetValue(key, defaultValue));
        }

        private T GetValueEnum<T>(string key, T defaultValue)
        {
            return (T)Enum.Parse(typeof(T), GetValue(key, defaultValue), true);
        }

        public string GetValue(string key, object defaultValue, bool persist = false)
        {
            key = key.ToLowerInvariant();
            Ensure.That(key, () => key).IsNotNullOrWhiteSpace();

            EnsureCache();

            string dbValue;

            if (_cache.TryGetValue(key, out dbValue) && dbValue != null && !string.IsNullOrEmpty(dbValue))
            {
                return dbValue;
            }

            _logger.Trace("Using default config value for '{0}' defaultValue:'{1}'", key, defaultValue);

            if (persist)
            {
                SetValue(key, defaultValue.ToString());
            }

            return defaultValue.ToString();
        }

        private void SetValue(string key, bool value)
        {
            SetValue(key, value.ToString());
        }

        private void SetValue(string key, int value)
        {
            SetValue(key, value.ToString());
        }

        private void SetValue(string key, Enum value)
        {
            SetValue(key, value.ToString().ToLower());
        }

        private void SetValue(string key, string value)
        {
            key = key.ToLowerInvariant();

            _logger.Trace("Writing Setting to database. Key:'{0}' Value:'{1}'", key, value);
            _repository.Upsert(key, value);

            ClearCache();
        }

        private void EnsureCache()
        {
            lock (_cache)
            {
                if (!_cache.Any())
                {
                    var all = _repository.All();
                    _cache = all.ToDictionary(c => c.Key.ToLower(), c => c.Value);
                }
            }
        }

        private static void ClearCache()
        {
            lock (_cache)
            {
                _cache = new Dictionary<string, string>();
            }
        }
    }
}
