Merge pull request 'dev_0.2' (#4) from dev_0.2 into master

Reviewed-on: #4

IO/IStore.cs

@@ -6,5 +6,9 @@ public interface IStore<T> : IDisposable
 
     public bool Add(T item);
 
+    public bool Has(T item);
+
+    public bool Remove(T item);
+
     public IEnumerable<T> GetValues();
 }

IO/LocalStore.cs

@@ -29,6 +29,9 @@ public class LocalStore<T> : IStore<T>
             using (FileStream fs = new FileStream(this.filePath, FileMode.OpenOrCreate))
             using (StreamWriter writer = new StreamWriter(fs, DefaultEncoding))
             {
+                fs.Seek(0, SeekOrigin.Begin);
+                fs.SetLength(0);
+
                 foreach (T item in this.items)
                 {
                     string json = JsonSerializer.Serialize<T>(item);
@@ -53,6 +56,16 @@ public class LocalStore<T> : IStore<T>
         return true;
     }
 
+    public bool Has(T item)
+    {
+        return this.items.Contains(item);
+    }
+
+    public bool Remove(T item)
+    {
+        return this.items.Remove(item);
+    }
+
     public IEnumerable<T> GetValues()
     {
         return this.items.ToList();

JsonDB.cs

@@ -26,6 +26,16 @@ public class JsonDB<T> : IDisposable
         return this.store.Add(item);
     }
 
+    public bool Has(T item)
+    {
+        return this.store.Has(item);
+    }
+
+    public bool Remove(T item)
+    {
+        return this.store.Remove(item);
+    }
+
     public IEnumerable<T> GetValues()
     {
         return this.store.GetValues();