Introduce the ISelection service

This service is a provides access to the active selection and selection of individual modules without involving COM wrappers directly; the interface only uses QMNs and selections.

Author: MDoerner

Rubberduck.VBEEditor/Utility/ISelectionService.cs

@@ -0,0 +1,12 @@
+namespace Rubberduck.VBEditor.Utility
+{
+    public interface ISelectionService
+    {
+        QualifiedSelection? ActiveSelection();
+        Selection? Selection(QualifiedModuleName module);
+        bool TryActivate(QualifiedModuleName module);
+        bool TrySetActiveSelection(QualifiedSelection selection);
+        bool TrySetSelection(QualifiedModuleName module, Selection selection);
+        bool TrySetSelection(QualifiedSelection selection);
+    }
+}

Rubberduck.VBEEditor/Utility/SelectionService.cs

@@ -0,0 +1,113 @@
+using System;
+using Rubberduck.VBEditor.ComManagement;
+using Rubberduck.VBEditor.SafeComWrappers.Abstract;
+
+namespace Rubberduck.VBEditor.Utility
+{
+    public class SelectionService : ISelectionService
+    {
+        private readonly IProjectsProvider _projectsProvider;
+        private readonly IVBE _vbe;
+
+        public SelectionService(IVBE vbe, IProjectsProvider projectsProvider)
+        {
+            _vbe = vbe;
+            _projectsProvider = projectsProvider;
+        }
+
+
+        public QualifiedSelection? ActiveSelection()
+        {
+            using (var activeCodePane = _vbe.ActiveCodePane)
+            {
+                return activeCodePane?.GetQualifiedSelection();
+            }
+        }
+
+        public Selection? Selection(QualifiedModuleName module)
+        {
+            var component = _projectsProvider.Component(module);
+            if (component == null)
+            {
+                return null;
+            }
+
+            using (var codeModule = component.CodeModule)
+            using (var codePane = codeModule.CodePane)
+            {
+                return codePane.Selection;
+            }
+        }
+
+        public bool TryActivate(QualifiedModuleName module)
+        {
+            try
+            {
+                var component = _projectsProvider.Component(module);
+                if (component == null)
+                {
+                    return false;
+                }
+
+                using (var codeModule = component.CodeModule)
+                using(var codePane = codeModule.CodePane)
+                {
+                    _vbe.ActiveCodePane = codePane;
+                }
+
+                return true;
+            }
+            catch (Exception)
+            {
+                return false;
+            }
+        }
+
+        public bool TrySetActiveSelection(QualifiedSelection selection)
+        {
+            var activeCodePane = _vbe.ActiveCodePane;
+
+            if (!TryActivate(selection.QualifiedName))
+            {
+                return false;
+            }
+
+            if (!TrySetSelection(selection))
+            {
+                TryActivate(activeCodePane.QualifiedModuleName);
+                return false;
+            }
+
+            return true;
+        }
+
+        public bool TrySetSelection(QualifiedModuleName module, Selection selection)
+        {
+            try
+            {
+                var component = _projectsProvider.Component(module);
+                if (component == null)
+                {
+                    return false;
+                }
+
+                using (var codeModule = component.CodeModule)
+                using (var codePane = codeModule.CodePane)
+                {
+                    codePane.Selection = selection;
+                }
+
+                return true;
+            }
+            catch (Exception)
+            {
+                return false;
+            }
+        }
+
+        public bool TrySetSelection(QualifiedSelection selection)
+        {
+            return TrySetSelection(selection.QualifiedName, selection.Selection);
+        }
+    }
+}