Merge lp:~elementary-apps/slingshot/synapse-calculator into lp:~elementary-pantheon/slingshot/trunk

[Tom Beckmann]

Add Synapse calculator plugin to fix bug #1335526

adds the calculator plugin back in, as proposed in https://bugs.launchpad.net/slingshot/+bug/1335526

=== modified file 'lib/synapse-plugins/CMakeLists.txt'
--- lib/synapse-plugins/CMakeLists.txt	2014-06-13 21:09:06 +0000
+++ lib/synapse-plugins/CMakeLists.txt	2014-06-29 14:57:08 +0000
@@ -11,6 +11,7 @@
 pkg_check_modules(PLUGINS_DEPS REQUIRED ${PLUGINS_PKG})
 
 set(PLUGINS_SOURCE
+    calculator-plugin.vala
     command-plugin.vala
     desktop-file-plugin.vala
 )

=== added file 'lib/synapse-plugins/calculator-plugin.vala'
--- lib/synapse-plugins/calculator-plugin.vala	1970-01-01 00:00:00 +0000
+++ lib/synapse-plugins/calculator-plugin.vala	2014-06-29 14:57:08 +0000
@@ -0,0 +1,151 @@
+/*
+ * Copyright (C) 2010 Michal Hruby <[e-mail]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA.
+ *
+ * Authored by Magnus Kulke <[e-mail]>
+ *
+ */
+
+namespace Synapse
+{
+  public class CalculatorPlugin: Object, Activatable, ItemProvider
+  {
+    public bool enabled { get; set; default = true; }
+
+    public void activate ()
+    {
+      
+    }
+
+    public void deactivate ()
+    {
+      
+    }
+
+    private class Result: Object, Match
+    {
+      // from Match interface
+      public string title { get; construct set; }
+      public string description { get; set; }
+      public string icon_name { get; construct set; }
+      public bool has_thumbnail { get; construct set; }
+      public string thumbnail_path { get; construct set; }
+      public MatchType match_type { get; construct set; }
+
+      public int default_relevancy { get; set; default = 0; }
+
+      public Result (double result, string match_string)
+      {
+        Object (match_type: MatchType.TEXT,
+                title: "%g".printf (result),
+                description: "%s = %g".printf (match_string, result),
+                has_thumbnail: false, icon_name: "accessories-calculator");
+      }
+    }
+
+    static void register_plugin ()
+    {
+      DataSink.PluginRegistry.get_default ().register_plugin (
+        typeof (CalculatorPlugin),
+        _ ("Calculator"),
+        _ ("Calculate basic expressions."),
+        "accessories-calculator",
+        register_plugin,
+        Environment.find_program_in_path ("bc") != null,
+        _ ("bc is not installed")
+      );
+    }
+
+    static construct
+    {
+      register_plugin ();
+    }
+
+    private Regex regex;
+
+    construct
+    {
+      /* The regex describes a string which *resembles* a mathematical expression. It does not
+         check for pairs of parantheses to be used correctly and only whitespace-stripped strings
+         will match. Basically it matches strings of the form: 
+         "paratheses_open* number (operator paratheses_open* number paratheses_close*)+"
+      */
+      try
+      {
+        regex = new Regex ("^\\(*(-?\\d+([.,]\\d+)?)([*/+-^]\\(*(-?\\d+([.,]\\d+)?)\\)*)+$",
+                         RegexCompileFlags.OPTIMIZE);
+      } catch (Error e) {
+        Utils.Logger.error (this, "Error creating regexp.");
+      }
+    }
+    
+    public bool handles_query (Query query)
+    {
+      return (QueryFlags.ACTIONS in query.query_type);
+    }
+
+    public async ResultSet? search (Query query) throws SearchError
+    { 
+      string input = query.query_string.replace (" ", "").replace (",", ".");
+      bool matched = regex.match (input);
+      if (!matched && input.length > 1)
+      {
+        input = input[0 : input.length - 1];
+        matched = regex.match (input);
+      }
+      if (matched)
+      {
+        Pid pid;
+        int read_fd, write_fd;
+        string[] argv = {"bc", "-l"};
+        string? solution = null;
+
+        try
+        {
+          Process.spawn_async_with_pipes (null, argv, null,
+                                          SpawnFlags.SEARCH_PATH,
+                                          null, out pid, out write_fd, out read_fd);
+          UnixInputStream read_stream = new UnixInputStream (read_fd, true);
+          DataInputStream bc_output = new DataInputStream (read_stream);
+
+          UnixOutputStream write_stream = new UnixOutputStream (write_fd, true);
+          DataOutputStream bc_input = new DataOutputStream (write_stream);
+
+          bc_input.put_string (input + "\n", query.cancellable);
+          yield bc_input.close_async (Priority.DEFAULT, query.cancellable);
+          solution = yield bc_output.read_line_async (Priority.DEFAULT_IDLE, query.cancellable);
+
+          if (solution != null)
+          {
+            double d = double.parse (solution);
+            Result result = new Result (d, query.query_string);
+            ResultSet results = new ResultSet ();
+            results.add (result, Match.Score.AVERAGE);
+            query.check_cancellable ();
+            return results;
+          }
+        }
+        catch (Error err)
+        {
+          if (!query.is_cancelled ()) warning ("%s", err.message);
+        }
+      }
+
+      query.check_cancellable ();
+      return null;
+    }
+  }
+}

=== modified file 'src/Backend/SynapseSearch.vala'
--- src/Backend/SynapseSearch.vala	2014-06-12 09:14:57 +0000
+++ src/Backend/SynapseSearch.vala	2014-06-29 14:57:08 +0000
@@ -21,6 +21,7 @@
     public class SynapseSearch : Object {
 
         private static Type[] plugins = {
+            typeof (Synapse.CalculatorPlugin),
             typeof (Synapse.CommandPlugin),
             typeof (Synapse.DesktopFilePlugin)
         };