bump .NET to v4.8, reduce directory searches

1. Update .NET Framework to 4.8
    (this may not be necessary, but I can't
    compile this project without it)
    If you want to change this back to 4.0, fine by me.
2. Add a check if Notepad++ is shutting down before updating file list
    (NPPN_BUFFERACTIVATED events fire when
    Notepad++ is shutting down, but the user doesn't care
    about the file list at that point)
3. When files in the current file's directory are queried,
    only update those files at the following times:
    * if no files in directory list exists yet
    * when a new buffer is activated
    * if the last refresh of the files in directory list
        was at least N seconds ago
        (where N is the value of the
        Settings.secondsBetweenDirectoryScans variable)
4. Because querying the files in the directory is much faster now,
    change the search algorithm so that it checks if all words
    in the search box are in the current file's directory
    and the menu commands
    (to be consistent with the behavior for searching tabs)

Author: molsonkiko

NppNavigateTo/Forms/FrmNavigateTo.cs

@@ -42,43 +42,76 @@ partial class FrmNavigateTo : Form
 
         public List<string> SelectedFiles { get; set; }
 
+        public string[] filesInCurrentDirectory { get; set; }
+
+        public bool shouldReloadFilesInDirectory { get; set; }
+
+        public long lastDirectoryReloadTimeTicks { get; set; }
+
+        public bool isShuttingDown { get; set; }
+
         public bool IsFuzzyResult { get; set; }
 
         public FrmNavigateTo(IScintillaGateway editor, INotepadPPGateway notepad)
         {
             this.editor = editor;
             this.notepad = notepad;
             this.SelectedFiles = new List<string>();
+            filesInCurrentDirectory = null;
+            shouldReloadFilesInDirectory = true;
             IsFuzzyResult = false;
             InitializeComponent();
             ReloadFileList();
             this.notepad.ReloadMenuItems();
         }
 
-        void SearchInCurrentDirectory(string s, string searchPattern1)
+        private static bool MatchesAllWordsInFilter(string s, string[] words)
+        {
+            return words.All(word => 
+                s.IndexOf(word, StringComparison.CurrentCultureIgnoreCase) >= 0
+            );
+        }
+
+        void SearchInCurrentDirectory(string[] words)
         {
             string currentFilePath = notepad.GetCurrentFileDirectory();
-            if (!String.IsNullOrWhiteSpace(currentFilePath))
-            {
-                bool searchInSubDirs = FrmSettings.Settings.GetBoolSetting(Settings.searchInSubDirs);
-                foreach (var filePath in Directory.GetFiles(currentFilePath, searchPattern1,
-                                 searchInSubDirs ? SearchOption.AllDirectories : SearchOption.TopDirectoryOnly)
-                             .AsParallel().Where(e =>
-                                 e.IndexOf(s, StringComparison.CurrentCultureIgnoreCase) >= 0 ||
-                                 e.Contains(s))
-                             .ToList())
+            if (string.IsNullOrWhiteSpace(currentFilePath))
+                return;
+            bool searchInSubDirs = FrmSettings.Settings.GetBoolSetting(Settings.searchInSubDirs);
+            long nextTimeToRefresh = lastDirectoryReloadTimeTicks +
+                10_000_000 * FrmSettings.Settings.GetIntSetting(Settings.secondsBetweenDirectoryScans); // 10 million ticks/sec
+            if (shouldReloadFilesInDirectory ||
+                filesInCurrentDirectory == null ||
+                DateTime.UtcNow.Ticks >= nextTimeToRefresh)
+            {
+                // only load the files in current directory as needed
+                // the correct files to load will depend on the active buffer
+                filesInCurrentDirectory = Directory.GetFiles(
+                    currentFilePath,
+                    "*.*",
+                    searchInSubDirs ? SearchOption.AllDirectories : SearchOption.TopDirectoryOnly
+                );
+                shouldReloadFilesInDirectory = false;
+                lastDirectoryReloadTimeTicks = DateTime.UtcNow.Ticks;
+            }
+            foreach (var filePath in filesInCurrentDirectory
+                            .AsParallel().Where(fname => MatchesAllWordsInFilter(fname, words))
+                            .ToList())
+            {
+                if (!FilteredFileList.Exists(file => file.FilePath.Equals(filePath)))
                 {
-                    if (!FilteredFileList.Exists(file => file.FilePath.Equals(filePath)))
-                    {
-                        FilteredFileList.Add(new FileModel(Path.GetFileName(filePath), filePath, -1, -1,
-                            searchInSubDirs ? FOLDER_SUB : FOLDER_TOP, 0));
-                    }
+                    FilteredFileList.Add(new FileModel(Path.GetFileName(filePath), filePath, -1, -1,
+                        searchInSubDirs ? FOLDER_SUB : FOLDER_TOP, 0));
                 }
             }
         }
 
         public void FilterDataGrid(string filter)
         {
+            // a bunch of NPPN_BUFFERACTIVATED events fire when Notepad++ is shutting down
+            // which will lead to this being called repeatedly
+            if (isShuttingDown)
+                return;
             if (!string.IsNullOrEmpty(searchComboBox.Text)) filter = searchComboBox.Text;
 
             if (!string.IsNullOrWhiteSpace(filter))
@@ -117,16 +150,17 @@ public void FilterDataGrid(string filter)
             }
             else
             {
+                var words = filter.Split(' ').Where(x => !string.IsNullOrWhiteSpace(x)).ToArray();
                 searchInTabs(filter);
 
                 if (FrmSettings.Settings.GetBoolSetting(Settings.searchInCurrentFolder))
                 {
-                    SearchInCurrentDirectory(filter, searchPattern);
+                    SearchInCurrentDirectory(words);
                 }
 
                 if (FrmSettings.Settings.GetBoolSetting(Settings.searchMenuCommands))
                 {
-                    FilterMenuCommands(filter);
+                    FilterMenuCommands(words);
                 }
 
                 FilteredFileList.ForEach(file =>
@@ -181,13 +215,11 @@ private void searchInTabs(string filter)
                 if (FrmSettings.Settings.GetBoolSetting(Settings.preferFilenameResults))
                 {
                     FilteredFileList = FileList.AsParallel()
-                        .Where(e => words.All(word =>
-                            e.FileName.IndexOf(word, StringComparison.CurrentCultureIgnoreCase) >= 0))
+                        .Where(e => MatchesAllWordsInFilter(e.FileName, words))
                         .ToList();
 
                     FileList.AsParallel()
-                        .Where(e => words.All(word =>
-                            e.FilePath.IndexOf(filter, StringComparison.CurrentCultureIgnoreCase) >= 0))
+                        .Where(e => MatchesAllWordsInFilter(e.FilePath, words))
                         .ToList().ForEach(filePath =>
                             {
                                 if (!FilteredFileList.Exists(file => file.FilePath.Equals(filePath.FilePath)))
@@ -200,10 +232,10 @@ private void searchInTabs(string filter)
                 else
                 {
                     FilteredFileList = FileList.AsParallel()
-                        .Where(e => words.All(word =>
-                            e.FilePath.IndexOf(word, StringComparison.CurrentCultureIgnoreCase) >= 0 ||
-                            e.FileName.IndexOf(word, StringComparison.CurrentCultureIgnoreCase) >= 0))
-                        .ToList();
+                        .Where(e =>
+                            MatchesAllWordsInFilter(e.FilePath, words) ||
+                            MatchesAllWordsInFilter(e.FileName, words)
+                        ).ToList();
                 }
             }
 
@@ -236,11 +268,11 @@ private void searchInTabs(string filter)
             }
         }
 
-        private void FilterMenuCommands(string filter)
+        private void FilterMenuCommands(string[] filterWords)
         {
-            foreach (var nppMenuCmd in notepad.MainMenuItems.AsParallel().Where(e => e.Value.IndexOf(filter,
-                             StringComparison.CurrentCultureIgnoreCase) >= 0 ||
-                         e.Value.Contains(filter)).ToList())
+            foreach (var nppMenuCmd in notepad.MainMenuItems.AsParallel().Where(e => 
+                MatchesAllWordsInFilter(e.Value, filterWords)
+            ).ToList())
             {
                 FilteredFileList.Add(new FileModel(
                     nppMenuCmd.Key.ToString(),
@@ -251,6 +283,8 @@ private void FilterMenuCommands(string filter)
 
         public void ReloadFileList()
         {
+            if (isShuttingDown)
+                return;
             if (FileList == null) FileList = new List<FileModel>();
             FileList.Clear();
             int firstViewCount =

NppNavigateTo/Forms/FrmSettings.cs

@@ -62,6 +62,7 @@ private void frmSettings_Shown(object sender, EventArgs e)
             numericUpDownMinGridWidth.Value = Settings.GetIntSetting(Settings.gridMinWidth);
             checkBoxSearchInFolder.Checked = Settings.GetBoolSetting(Settings.searchInCurrentFolder);
             checkBoxSearchInSubDirs.Checked = Settings.GetBoolSetting(Settings.searchInSubDirs);
+            numUpDownSecsBetweenDirectoryScans.Value = Settings.GetIntSetting(Settings.secondsBetweenDirectoryScans);
             checkBoxSearchMenu.Checked = Settings.GetBoolSetting(Settings.searchMenuCommands);
             checkBoxCleanSearch.Checked = Settings.GetBoolSetting(Settings.clearOnClose);
             checkBoxKeepSelected.Checked = Settings.GetBoolSetting(Settings.selectFirstRowOnFilter);
@@ -333,5 +334,10 @@ private void buttonRowBackgroud_Click(object sender, EventArgs e)
 
             RefreshDataGridStyles();
         }
+
+        private void secondsBetweenDirectoryScans_ValueChanged(object sender, EventArgs e)
+        {
+            Settings.SetIntSetting(Settings.secondsBetweenDirectoryScans, (int)numUpDownSecsBetweenDirectoryScans.Value);
+        }
     }
 }