src/Files.App/Utils/Serialization/Implementation/CachingJsonSettingsDatabase.cs - main - githubmirror/Files

src/Files.App/Utils/Serialization/Implementation/CachingJsonSettingsDatabase.cs

88 строк2 KB

Yair

Code Quality: Updated license header

31 дек 2024, 05:03

31 дек 2024, 05:038436c6d

// Copyright (c) Files Community
// Licensed under the MIT License.

namespace Files.App.Utils.Serialization.Implementation
{
	internal sealed class CachingJsonSettingsDatabase : DefaultJsonSettingsDatabase
	{
		private IDictionary<string, object?>? _settingsCache;

		public CachingJsonSettingsDatabase(ISettingsSerializer settingsSerializer, IJsonSettingsSerializer jsonSettingsSerializer)
			: base(settingsSerializer, jsonSettingsSerializer)
		{
		}

		public override TValue? GetValue<TValue>(string key, TValue? defaultValue = default) where TValue : default
		{
			_settingsCache ??= GetFreshSettings();

			if (_settingsCache.TryGetValue(key, out var objVal))
			{
				return GetValueFromObject<TValue>(objVal) ?? defaultValue;
			}
			else
			{
				if (base.SetValue(key, defaultValue))
					_settingsCache.TryAdd(key, defaultValue);

				return defaultValue;
			}
		}

		public override bool SetValue<TValue>(string key, TValue? newValue) where TValue : default
		{
			_settingsCache ??= GetFreshSettings();

			if (_settingsCache.TryAdd(key, newValue))
				return SaveSettings(_settingsCache);
			else
				return UpdateValueInCache(_settingsCache[key]);

			bool UpdateValueInCache(object? value)
			{
				bool isDifferent;

				if (newValue is IEnumerable enumerableNewValue && value is IEnumerable enumerableValue)
				{
					isDifferent = !enumerableValue.Cast<object>().SequenceEqual(enumerableNewValue.Cast<object>());
				}
				else
				{
					isDifferent = value != (object?)newValue;
				}

				if (isDifferent)
				{
					// Values are different, update the value and reload the cache.
					_settingsCache[key] = newValue;

					return SaveSettings(_settingsCache);
				}
				else
				{
					// The cache does not need to be updated, continue.
					return false;
				}
			}
		}

		public override bool RemoveKey(string key)
		{
			_settingsCache ??= GetFreshSettings();

			return _settingsCache.Remove(key) && SaveSettings(_settingsCache);
		}

		public override bool ImportSettings(object? import)
		{
			if (base.ImportSettings(import))
			{
				_settingsCache = GetFreshSettings();

				return true;
			}

			return false;
		}
	}
}