FEATURE: Calculator Plugin History

Flow.Launcher.Test/Plugins/CalculatorTest.cs

@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Reflection;
 using Flow.Launcher.Plugin.Calculator;
+using Flow.Launcher.Plugin.Calculator.Storage;
 using Mages.Core;
 using NUnit.Framework;
 using NUnit.Framework.Legacy;
@@ -17,7 +18,8 @@ public class CalculatorPluginTest
             DecimalSeparator = DecimalSeparator.UseSystemLocale,
             MaxDecimalPlaces = 10,
             ShowErrorMessage = false, // Make sure we return the empty results when error occurs
-            UseThousandsSeparator = true // Default value
+            UseThousandsSeparator = true, // Default value
+            EnableHistory = true,
         };
         private readonly Engine _engine = new(new Configuration
         {
@@ -42,6 +44,12 @@ public CalculatorPluginTest()
             engineField.SetValue(null, _engine);
         }
 
+        [SetUp]
+        public void SetUp()
+        {
+            GetHistory().Items.Clear();
+        }
+
         [Test]
         public void ThousandsSeparatorTest_Enabled()
         {
@@ -80,6 +88,27 @@ public void ThousandsSeparatorTest_LargeNumber()
             ClassicAssert.AreEqual("1234567", result);
         }
 
+        [Test]
+        public void CalculationHistory_IsStoredWhenEnabled()
+        {
+            _settings.EnableHistory = true;
+
+            _plugin.Query(new Plugin.Query { Search = "1+1" });
+
+            ClassicAssert.AreEqual(1, GetHistory().Items.Count);
+            ClassicAssert.AreEqual("1+1", GetHistory().Items[0].Query);
+        }
+
+        [Test]
+        public void CalculationHistory_IsNotStoredWhenDisabled()
+        {
+            _settings.EnableHistory = false;
+
+            _plugin.Query(new Plugin.Query { Search = "1+1" });
+
+            ClassicAssert.AreEqual(0, GetHistory().Items.Count);
+        }
+
         // Basic operations
         [TestCase(@"1+1", "2")]
         [TestCase(@"2-1", "1")]
@@ -130,5 +159,18 @@ private string GetCalculationResult(string expression)
             });
             return results.Count > 0 ? results[0].Title : string.Empty;
         }
+
+        private static History GetHistory()
+        {
+            var historyField = typeof(Main).GetField("History", BindingFlags.NonPublic | BindingFlags.Static);
+            Assert.That(historyField, Is.Not.Null,
+                "Could not find static field 'History' on Flow.Launcher.Plugin.Calculator.Main");
+
+            var history = historyField!.GetValue(null) as History;
+            Assert.That(history, Is.Not.Null,
+                "Static field 'History' on Flow.Launcher.Plugin.Calculator.Main' was not a calculator History instance");
+
+            return history!;
+        }
     }
 }

Plugins/Flow.Launcher.Plugin.Calculator/Languages/en.xaml

@@ -17,4 +17,6 @@
     <system:String x:Key="flowlauncher_plugin_calculator_use_thousands_separator">Show thousands separator in results</system:String>
     <system:String x:Key="flowlauncher_plugin_calculator_failed_to_copy">Copy failed, please try later</system:String>
     <system:String x:Key="flowlauncher_plugin_calculator_show_error_message">Show error message when calculation fails</system:String>
-</ResourceDictionary>
+    <system:String x:Key="flowlauncher_plugin_calculator_enable_history">Enable History</system:String>
+    <system:String x:Key="flowlauncher_plugin_calculator_history_subtitle">Calculated at {0}</system:String>
+</ResourceDictionary>

Plugins/Flow.Launcher.Plugin.Calculator/Main.cs

@@ -5,6 +5,7 @@
 using System.Runtime.InteropServices;
 using System.Text.RegularExpressions;
 using System.Windows.Controls;
+using Flow.Launcher.Plugin.Calculator.Storage;
 using Flow.Launcher.Plugin.Calculator.ViewModels;
 using Flow.Launcher.Plugin.Calculator.Views;
 using Mages.Core;
@@ -24,8 +25,10 @@ public class Main : IPlugin, IPluginI18n, ISettingProvider
         private const string Comma = ",";
         private const string Dot = ".";
         private const string IcoPath = "Images/calculator.png";
+
         private static readonly List<Result> EmptyResults = [];
 
+        private History History { get; set; } = null!;
         internal static PluginInitContext Context { get; private set; } = null!;
 
         private Settings _settings;
@@ -35,6 +38,7 @@ public void Init(PluginInitContext context)
         {
             Context = context;
             _settings = context.API.LoadSettingJsonStorage<Settings>();
+            History = context.API.LoadSettingJsonStorage<History>();
             _viewModel = new SettingsViewModel(_settings);
 
             MagesEngine = new Engine(new Configuration
@@ -57,7 +61,7 @@ public List<Result> Query(Query query)
             {
                 var search = query.Search;
                 bool isFunctionPresent = FunctionRegex.IsMatch(search);
-
+                bool isValidResultToAddHistory = true;
                 // Mages is case sensitive, so we need to convert all function names to lower case.
                 search = FunctionRegex.Replace(search, m => m.Value.ToLowerInvariant());
 
@@ -119,43 +123,47 @@ public List<Result> Query(Query query)
                 if (result.ToString() == "NaN")
                 {
                     result = Localize.flowlauncher_plugin_calculator_not_a_number();
+                    isValidResultToAddHistory = false;
                 }
 
                 if (result is Function)
                 {
                     result = Localize.flowlauncher_plugin_calculator_expression_not_complete();
+                    isValidResultToAddHistory = false;
                 }
 
                 if (!string.IsNullOrEmpty(result.ToString()))
                 {
                     decimal roundedResult = Math.Round(Convert.ToDecimal(result), _settings.MaxDecimalPlaces, MidpointRounding.AwayFromZero);
                     string newResult = FormatResult(roundedResult);
+
+                    var results = new List<Result>();
+                    var action = CreateClipboardAction(newResult);
+                    var resultObject = new Result
+                    {
+                        Title = newResult,
+                        IcoPath = IcoPath,
+                        Score = 300,
+                        // Check context nullability for unit testing
+                        SubTitle = Context == null
+                            ? string.Empty
+                            : Localize.flowlauncher_plugin_calculator_copy_number_to_clipboard(),
+                        CopyText = newResult,
+                        Action = action
+                    };
+
+
+                    if (isValidResultToAddHistory)
+                    {
+                        History.AddOrUpdate(new History.PendingHistoryItem(resultObject, expression, action));
+                    }
+
+                    results.Add(resultObject);
+                    var historyItems = _settings.EnableHistory
+                        ? History.GetItemsExcluding(expression)
+                        : [];
+                    return results.Concat(historyItems).ToList();
 
-                    return
-                    [
-                        new Result
-                        {
-                            Title = newResult,
-                            IcoPath = IcoPath,
-                            Score = 300,
-                            // Check context nullability for unit testing
-                            SubTitle = Context == null ? string.Empty : Localize.flowlauncher_plugin_calculator_copy_number_to_clipboard(),
-                            CopyText = newResult,
-                            Action = c =>
-                            {
-                                try
-                                {
-                                    Context.API.CopyToClipboard(newResult);
-                                    return true;
-                                }
-                                catch (ExternalException)
-                                {
-                                    Context.API.ShowMsgBox(Localize.flowlauncher_plugin_calculator_failed_to_copy());
-                                    return false;
-                                }
-                            }
-                        }
-                    ];
                 }
             }
             catch (Exception)
@@ -175,6 +183,27 @@ public List<Result> Query(Query query)
             return EmptyResults;
         }
 
+
+        private Func<ActionContext, bool> CreateClipboardAction(string newResult)
+        {
+            return (_) =>
+            {
+                try
+                {
+                    Context.API.CopyToClipboard(newResult);
+
+                    return true;
+                }
+                catch (ExternalException)
+                {
+                    Context.API.ShowMsgBox(
+                        Localize.flowlauncher_plugin_calculator_failed_to_copy()
+                    );
+                    return false;
+                }
+            };
+        }
+
         private static string PowMatchEvaluator(Match m)
         {
             // m.Groups[1].Value will be `(...)` with parens

Plugins/Flow.Launcher.Plugin.Calculator/Settings.cs

@@ -9,4 +9,6 @@ public class Settings
     public bool ShowErrorMessage { get; set; } = false;
 
     public bool UseThousandsSeparator { get; set; } = true;
+
+    public bool EnableHistory { get; set; } = false;
 }

Plugins/Flow.Launcher.Plugin.Calculator/Storage/History.cs

@@ -0,0 +1,85 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text.Json.Serialization;
+using System.Threading;
+
+namespace Flow.Launcher.Plugin.Calculator.Storage;
+
+public class History
+{
+    private const int MaxItems = 5;
+    private const int DebounceDelayMs = 800;
+
+    [JsonInclude]
+    public List<HistoryItem> Items { get; set; } = [];
+
+    [JsonIgnore]
+    private readonly Lock _syncRoot = new();
+
+    [JsonIgnore]
+    private Timer _debounceTimer;
+
+    [JsonIgnore]
+    private PendingHistoryItem _pendingItem;
+
+    public void AddOrUpdate(PendingHistoryItem pendingItem)
+    {
+        lock (_syncRoot)
+        {
+            _pendingItem = pendingItem;
+
+            if (_debounceTimer == null)
+            {
+                _debounceTimer = new Timer(_ => FlushPendingItem(), null, DebounceDelayMs, Timeout.Infinite);
+            }
+            else
+            {
+                _debounceTimer.Change(DebounceDelayMs, Timeout.Infinite);
+            }
+        }
+    }
+
+    public List<HistoryItem> GetItemsExcluding(string expression)
+    {
+        lock (_syncRoot)
+        {
+            return Items
+                .Where(x => x.Query != expression)
+                .OrderByDescending(x => x.CalculatedAt)
+                .ToList();
+        }
+    }
+
+    private void FlushPendingItem()
+    {
+        lock (_syncRoot)
+        {
+            if (_pendingItem == null)
+            {
+                return;
+            }
+
+            var currentItem = Items.FirstOrDefault(x => x.Query == _pendingItem.Expression);
+            if (currentItem != null)
+            {
+                currentItem.Refresh(_pendingItem.Result, _pendingItem.Action);
+            }
+            else
+            {
+                var item = new HistoryItem(_pendingItem.Result, _pendingItem.Expression, _pendingItem.Action);
+
+                if (Items.Count >= MaxItems)
+                {
+                    Items.RemoveAt(0);
+                }
+
+                Items.Add(item);
+            }
+
+            _pendingItem = null;
+        }
+    }
+
+    public sealed record PendingHistoryItem(Result Result, string Expression, Func<ActionContext, bool> Action);
+}

Plugins/Flow.Launcher.Plugin.Calculator/Storage/HistoryItem.cs

@@ -0,0 +1,46 @@
+using System;
+using System.Text.Json.Serialization;
+
+namespace Flow.Launcher.Plugin.Calculator.Storage;
+
+public class HistoryItem : Result
+{
+    public string Query { get; set; } = string.Empty;
+    public DateTime CalculatedAt { get; set; }
+
+    [JsonIgnore]
+    private const string BadgeIconPath = "Images/history.png";
+    public HistoryItem()
+    {
+    }
+
+    public HistoryItem(Result result, string expression, Func<ActionContext, bool> action)
+    {
+        CalculatedAt = DateTime.Now;
+        Title = expression;
+        SubTitle = CreateSubTitle(result.Title);
+        Score = 300;
+        IcoPath = result.IcoPath;
+        Query = expression;
+        BadgeIcoPath = BadgeIconPath;
+        ShowBadge = true;
+        CopyText = result.Title;
+        Action = action;
+    }
+
+    public void Refresh(Result result, Func<ActionContext, bool> action)
+    {
+        CalculatedAt = DateTime.Now;
+        SubTitle = CreateSubTitle(result.Title);
+        CopyText = result.Title;
+        Action = action;
+    }
+
+
+    private string CreateSubTitle(string value)
+    {
+        return
+            $"{value} - {Localize.flowlauncher_plugin_calculator_copy_number_to_clipboard()}" +
+            $"\n{Localize.flowlauncher_plugin_calculator_history_subtitle(CalculatedAt)}";
+    }
+}

Plugins/Flow.Launcher.Plugin.Calculator/Views/CalculatorSettings.xaml

@@ -17,6 +17,7 @@
             <RowDefinition Height="auto" />
             <RowDefinition Height="auto" />
             <RowDefinition Height="auto" />
+            <RowDefinition Height="auto" />
         </Grid.RowDefinitions>
         <Grid.ColumnDefinitions>
             <ColumnDefinition Width="Auto" />
@@ -79,5 +80,15 @@
             VerticalAlignment="Center"
             Content="{DynamicResource flowlauncher_plugin_calculator_show_error_message}"
             IsChecked="{Binding Settings.ShowErrorMessage, Mode=TwoWay}" />
+
+        <CheckBox
+            Grid.Row="4"
+            Grid.Column="0"
+            Grid.ColumnSpan="2"
+            Margin="{StaticResource SettingPanelItemTopBottomMargin}"
+            HorizontalAlignment="Left"
+            VerticalAlignment="Center"
+            Content="{DynamicResource flowlauncher_plugin_calculator_enable_history}"
+            IsChecked="{Binding Settings.EnableHistory, Mode=TwoWay}" />
     </Grid>
 </UserControl>