protected override void OnPreviewKeyDown(KeyEventArgs e)
{
if (_suggestionList.IsVisible && e.Key.In(Key.Tab, Key.Enter, Key.Return))
{
var selectedItem = (Suggestion)_suggestionList.SelectedItem;
if (selectedItem != null)
{
var selectedText = selectedItem.Completion;
var index = CaretIndex;
Text = Text.Insert(CaretIndex, selectedText);
CaretIndex = index + selectedText.Length;
}
HideSuggestionList();
e.Handled = true;
return;
}
if (e.Key == Key.Escape)
{
HideSuggestionList();
e.Handled = true;
}
if (ShouldShowSuggestionList(e))
{
SyntaxParser.FindSuggestions(Text, SelectionStart);
ShowSuggestionList();
e.Handled = true;
}
if (e.Key == Key.Tab && e.KeyboardDevice.Modifiers == ModifierKeys.Shift)
{
// with selected text
if (SelectedText != string.Empty)
{
string[] lines = SelectedText.SplitLines();
for (int ii = 0; ii < lines.Length; ii++)
{
if (lines[ii].StartsWith(Tab))
{
lines[ii] = lines[ii].Substring(Tab.Length);
}
else
{
lines[ii] = lines[ii].TrimStart(' ');
}
}
SelectedText = String.Join(Environment.NewLine, lines);
}
else
{
var index = CaretIndex;
var lastLine = Text.LastIndexOf(Environment.NewLine, index, StringComparison.Ordinal);
if (lastLine == -1)
{
lastLine = Text.Length - 1;
}
var startLine = Text.IndexOf(Environment.NewLine, lastLine, StringComparison.Ordinal);
if (startLine != -1)
{
startLine += Environment.NewLine.Length;
}
else
{
startLine = 0;
}
// find empty spaces
var spaces = 0;
for (var i = startLine; i < Text.Length - 1; i++)
{
if (Text[i] == ' ')
{
spaces++;
}
else
{
break;
}
}
if (spaces > TabSize)
{
spaces = TabSize;
}
Text = Text.Remove(startLine, spaces);
// set position of caret
if (index >= startLine + spaces)
{
CaretIndex = index - spaces;
}
else if (index >= startLine && index < startLine + spaces)
{
CaretIndex = startLine;
}
else
{
CaretIndex = index;
}
}
e.Handled = true;
}
// tab
if (e.Key == Key.Tab && e.KeyboardDevice.Modifiers == ModifierKeys.None)
{
if (SelectedText == string.Empty)
{
var caretPosition = CaretIndex;
Text = Text.Insert(caretPosition, Tab);
CaretIndex = caretPosition + TabSize;
}
else
{
if (!SelectedText.Contains(Environment.NewLine))
{
SelectedText = Tab;
}
else
{
SelectedText = Tab + SelectedText.Replace(Environment.NewLine, Environment.NewLine + Tab);
}
}
e.Handled = true;
}
// enter respects indenting
if (e.Key == Key.Return)
{
var index = CaretIndex;
var lastLine = Text.LastIndexOf(Environment.NewLine, index, StringComparison.Ordinal);
var spaces = 0;
if (lastLine != -1)
{
var line = Text.Substring(lastLine, Text.Length - lastLine);
var startLine = line.IndexOf(Environment.NewLine, StringComparison.Ordinal);
if (startLine != -1)
{
line = line.Substring(startLine).TrimStart('\r', '\n');
}
foreach (var c in line)
{
if (c == ' ')
{
spaces++;
}
else
{
break;
}
}
}
Text = Text.Insert(index, Environment.NewLine + new String(' ', spaces));
CaretIndex = index + Environment.NewLine.Length + spaces;
e.Handled = true;
}
base.OnPreviewKeyDown(e);
}