close #48 Refactor setting storage.

Wox.Infrastructure/Storage/BaseStorage.cs

@@ -0,0 +1,76 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Windows.Forms;
+using Newtonsoft.Json;
+
+namespace Wox.Infrastructure.Storage
+{
+    public abstract class BaseStorage<T> where T : class, new()
+    {
+        private string configFolder = Path.Combine(Path.GetDirectoryName(Application.ExecutablePath), "Config");
+        private string fileSuffix = ".json";
+        private static object locker = new object();
+        private static T storage;
+
+        protected abstract string ConfigName { get; }
+
+        public static T Instance
+        {
+            get
+            {
+                if (storage == null)
+                {
+                    lock (locker)
+                    {
+                        if (storage == null)
+                        {
+                            storage = new T();
+                            (storage as BaseStorage<T>).Load();
+                        }
+                    }
+                }
+                return storage;
+            }
+        }
+
+        private void Load()
+        {
+            string configPath = Path.Combine(configFolder, ConfigName + fileSuffix);
+            if (!File.Exists(configPath))
+            {
+                FileInfo fileInfo = new FileInfo(configFolder);
+                if (!fileInfo.Directory.Exists)
+                {
+                    fileInfo.Directory.Create();
+                }
+                File.Create(configPath).Close();
+            }
+            string json = File.ReadAllText(configPath);
+            if (!string.IsNullOrEmpty(json))
+            {
+                try
+                {
+                    storage = JsonConvert.DeserializeObject<T>(json);
+                }
+                catch (Exception)
+                {
+                    //no-op
+                }
+            }
+        }
+
+        public void Save()
+        {
+            lock (locker)
+            {
+                //json is a good choise, readable and flexiable
+                string configPath = Path.Combine(configFolder, ConfigName + fileSuffix);
+                string json = JsonConvert.SerializeObject(storage, Formatting.Indented);
+                File.WriteAllText(configPath, json);
+            }
+        }
+    }
+}