add Calculator system plugin

Wox.Plugin.System/Calculator.cs

@@ -0,0 +1,91 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Reflection;
+using System.Text;
+using System.Text.RegularExpressions;
+using System.Windows.Forms;
+using YAMP;
+
+namespace Wox.Plugin.System
+{
+    public class Calculator : BaseSystemPlugin
+    {
+        private static Regex regValidExpressChar = new Regex(
+                        @"^(" +
+                        @"sin|cos|ceil|floor|exp|pi|max|min|det|arccos|abs|" +
+                        @"eigval|eigvec|eig|sum|polar|plot|round|sort|real|zeta|" +
+                        @"bin2dec|hex2dec|oct2dec|" +
+                        @"==|~=|&&|\|\||" +
+                        @"[ei]|[0-9]|[\+\-\*\/\^\., ""]|[\(\)\|\!\[\]]" +
+                        @")+$", RegexOptions.Compiled);
+        private static Regex regBrackets = new Regex(@"[\(\)\[\]]", RegexOptions.Compiled);
+        private static ParseContext yampContext = null;
+        private PluginInitContext context { get; set; }
+
+        static Calculator()
+        {
+            yampContext = Parser.PrimaryContext;
+            Parser.InteractiveMode = false;
+            Parser.UseScripting = false;
+        }
+
+        protected override List<Result> QueryInternal(Query query)
+        {
+            if (string.IsNullOrEmpty(query.RawQuery)
+                || query.RawQuery.Length < 2          // don't affect when user only input "e" or "i" keyword
+                || !regValidExpressChar.IsMatch(query.RawQuery) 
+                || !IsBracketComplete(query.RawQuery)) return new List<Result>();
+
+            try
+            {
+                var result = yampContext.Run(query.RawQuery);
+                if (result.Output != null && !string.IsNullOrEmpty(result.Result))
+                {
+                    return new List<Result>() { new Result() { 
+                        Title = result.Result, 
+                        IcoPath = "Images/calculator.png", 
+                        Score = 300,
+                        SubTitle = "Copy this number to the clipboard", 
+                        Action = (c) =>
+                        {
+                            Clipboard.SetText(result.Result);
+                            return true;
+                        }
+                    } };
+                }
+            }
+            catch
+            {}
+
+            return new List<Result>();
+        }
+
+        private bool IsBracketComplete(string query)
+        {
+            var matchs = regBrackets.Matches(query);
+            var leftBracketCount = 0;
+            foreach (Match match in matchs)
+            {
+                if (match.Value == "(" || match.Value == "[")
+                {
+                    leftBracketCount++;
+                }
+                else
+                {
+                    leftBracketCount--;
+                }
+            }
+
+            return leftBracketCount == 0;
+        }
+
+        protected override void InitInternal(PluginInitContext context)
+        {
+            this.context = context;
+        }
+
+        
+    }
+}

Wox.Plugin.System/Wox.Plugin.System.csproj

@@ -35,6 +35,9 @@
     <Reference Include="Newtonsoft.Json">
       <HintPath>..\packages\Newtonsoft.Json.5.0.8\lib\net35\Newtonsoft.Json.dll</HintPath>
     </Reference>
+    <Reference Include="YAMP">
+      <HintPath>..\packages\YAMP.1.3.0\lib\net35\YAMP.dll</HintPath>
+    </Reference>
     <Reference Include="System" />
     <Reference Include="System.Core" />
     <Reference Include="System.Drawing" />
@@ -47,6 +50,7 @@
   <ItemGroup>
     <Compile Include="BaseSystemPlugin.cs" />
     <Compile Include="BrowserBookmarks.cs" />
+    <Compile Include="Calculator.cs" />
     <Compile Include="WebSearchPlugin.cs" />
     <Compile Include="WindowsShellRun.cs" />
     <Compile Include="CMD.cs" />

Wox.Plugin.System/packages.config

@@ -1,4 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
   <package id="Newtonsoft.Json" version="5.0.8" targetFramework="net35" />
+  <package id="YAMP" version="1.3.0" targetFramework="net35" />
 </packages>

Wox/Wox.csproj

@@ -307,6 +307,9 @@
     <Resource Include="Images\work.png">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </Resource>
+    <Resource Include="Images\calculator.png">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </Resource>
   </ItemGroup>
   <ItemGroup>
     <COMReference Include="IWshRuntimeLibrary">