public override string ReadLine(CancellationToken cancellationToken)
{
string inputBeforeCompletion = null;
string inputAfterCompletion = null;
CommandCompletion currentCompletion = null;
int historyIndex = -1;
IReadOnlyList <PSObject> currentHistory = null;
StringBuilder inputLine = new();
int initialCursorCol = ConsoleProxy.GetCursorLeft(cancellationToken);
int initialCursorRow = ConsoleProxy.GetCursorTop(cancellationToken);
int currentCursorIndex = 0;
Console.TreatControlCAsInput = true;
try
{
while (!cancellationToken.IsCancellationRequested)
{
ConsoleKeyInfo keyInfo = ReadKey(cancellationToken);
// Do final position calculation after the key has been pressed
// because the window could have been resized before then
int promptStartCol = initialCursorCol;
int promptStartRow = initialCursorRow;
int consoleWidth = Console.WindowWidth;
switch (keyInfo.Key)
{
case ConsoleKey.Tab:
if (currentCompletion == null)
{
inputBeforeCompletion = inputLine.ToString();
inputAfterCompletion = null;
// TODO: This logic should be moved to AstOperations or similar!
if (_psesHost.DebugContext.IsStopped)
{
PSCommand command = new PSCommand()
.AddCommand("TabExpansion2")
.AddParameter("InputScript", inputBeforeCompletion)
.AddParameter("CursorColumn", currentCursorIndex)
.AddParameter("Options", null);
currentCompletion = _psesHost.InvokePSCommand <CommandCompletion>(command, executionOptions: null, cancellationToken).FirstOrDefault();
}
else
{
currentCompletion = _psesHost.InvokePSDelegate(
"Legacy readline inline command completion",
executionOptions: null,
(pwsh, _) => CommandCompletion.CompleteInput(inputAfterCompletion, currentCursorIndex, options: null, pwsh),
cancellationToken);
if (currentCompletion.CompletionMatches.Count > 0)
{
int replacementEndIndex =
currentCompletion.ReplacementIndex +
currentCompletion.ReplacementLength;
inputAfterCompletion =
inputLine.ToString(
replacementEndIndex,
inputLine.Length - replacementEndIndex);
}
else
{
currentCompletion = null;
}
}
}
CompletionResult completion =
currentCompletion?.GetNextResult(
!keyInfo.Modifiers.HasFlag(ConsoleModifiers.Shift));
if (completion != null)
{
currentCursorIndex =
InsertInput(
inputLine,
promptStartCol,
promptStartRow,
$"{completion.CompletionText}{inputAfterCompletion}",
currentCursorIndex,
insertIndex: currentCompletion.ReplacementIndex,
replaceLength: inputLine.Length - currentCompletion.ReplacementIndex,
finalCursorIndex: currentCompletion.ReplacementIndex + completion.CompletionText.Length);
}
continue;
case ConsoleKey.LeftArrow:
currentCompletion = null;
if (currentCursorIndex > 0)
{
currentCursorIndex =
MoveCursorToIndex(
promptStartCol,
promptStartRow,
consoleWidth,
currentCursorIndex - 1);
}
continue;
case ConsoleKey.Home:
currentCompletion = null;
currentCursorIndex =
MoveCursorToIndex(
promptStartCol,
promptStartRow,
consoleWidth,
0);
continue;
case ConsoleKey.RightArrow:
currentCompletion = null;
if (currentCursorIndex < inputLine.Length)
{
currentCursorIndex =
MoveCursorToIndex(
promptStartCol,
promptStartRow,
consoleWidth,
currentCursorIndex + 1);
}
continue;
case ConsoleKey.End:
currentCompletion = null;
currentCursorIndex =
MoveCursorToIndex(
promptStartCol,
promptStartRow,
consoleWidth,
inputLine.Length);
continue;
case ConsoleKey.UpArrow:
currentCompletion = null;
// TODO: Ctrl+Up should allow navigation in multi-line input
if (currentHistory == null)
{
historyIndex = -1;
PSCommand command = new PSCommand()
.AddCommand("Get-History");
currentHistory = _psesHost.InvokePSCommand <PSObject>(command, executionOptions: null, cancellationToken);
if (currentHistory != null)
{
historyIndex = currentHistory.Count;
}
}
if (currentHistory != null && currentHistory.Count > 0 && historyIndex > 0)
{
historyIndex--;
currentCursorIndex =
InsertInput(
inputLine,
promptStartCol,
promptStartRow,
(string)currentHistory[historyIndex].Properties["CommandLine"].Value,
currentCursorIndex,
insertIndex: 0,
replaceLength: inputLine.Length);
}
continue;
case ConsoleKey.DownArrow:
currentCompletion = null;
// The down arrow shouldn't cause history to be loaded,
// it's only for navigating an active history array
if (historyIndex > -1 && historyIndex < currentHistory.Count &&
currentHistory != null && currentHistory.Count > 0)
{
historyIndex++;
if (historyIndex < currentHistory.Count)
{
currentCursorIndex =
InsertInput(
inputLine,
promptStartCol,
promptStartRow,
(string)currentHistory[historyIndex].Properties["CommandLine"].Value,
currentCursorIndex,
insertIndex: 0,
replaceLength: inputLine.Length);
}
else if (historyIndex == currentHistory.Count)
{
currentCursorIndex =
InsertInput(
inputLine,
promptStartCol,
promptStartRow,
string.Empty,
currentCursorIndex,
insertIndex: 0,
replaceLength: inputLine.Length);
}
}
continue;
case ConsoleKey.Escape:
currentCompletion = null;
historyIndex = currentHistory != null ? currentHistory.Count : -1;
currentCursorIndex =
InsertInput(
inputLine,
promptStartCol,
promptStartRow,
string.Empty,
currentCursorIndex,
insertIndex: 0,
replaceLength: inputLine.Length);
continue;
case ConsoleKey.Backspace:
currentCompletion = null;
if (currentCursorIndex > 0)
{
currentCursorIndex =
InsertInput(
inputLine,
promptStartCol,
promptStartRow,
string.Empty,
currentCursorIndex,
insertIndex: currentCursorIndex - 1,
replaceLength: 1,
finalCursorIndex: currentCursorIndex - 1);
}
continue;
case ConsoleKey.Delete:
currentCompletion = null;
if (currentCursorIndex < inputLine.Length)
{
currentCursorIndex =
InsertInput(
inputLine,
promptStartCol,
promptStartRow,
string.Empty,
currentCursorIndex,
replaceLength: 1,
finalCursorIndex: currentCursorIndex);
}
continue;
case ConsoleKey.Enter:
string completedInput = inputLine.ToString();
currentCompletion = null;
currentHistory = null;
// TODO: Add line continuation support:
// - When shift+enter is pressed, or
// - When the parse indicates incomplete input
//if ((keyInfo.Modifiers & ConsoleModifiers.Shift) == ConsoleModifiers.Shift)
//{
// // TODO: Start a new line!
// continue;
//}
//Parser.ParseInput(
// completedInput,
// out Token[] tokens,
// out ParseError[] parseErrors);
//if (parseErrors.Any(e => e.IncompleteInput))
//{
// // TODO: Start a new line!
// continue;
//}
return(completedInput);
default:
if (keyInfo.IsCtrlC())
{
throw new PipelineStoppedException();
}
// Normal character input
if (keyInfo.KeyChar != 0 && !char.IsControl(keyInfo.KeyChar))
{
currentCompletion = null;
currentCursorIndex =
InsertInput(
inputLine,
promptStartCol,
promptStartRow,
keyInfo.KeyChar.ToString(), // TODO: Determine whether this should take culture into account
currentCursorIndex,
finalCursorIndex: currentCursorIndex + 1);
}
continue;
}
}
}
catch (OperationCanceledException)
{
// We've broken out of the loop
}
finally
{
Console.TreatControlCAsInput = false;
}
// If we break out of the loop without returning (because of the Enter key)
// then the readline has been aborted in some way and we should return nothing
return(null);
}
protected override ConsoleKeyInfo ReadKey(CancellationToken cancellationToken) => ConsoleProxy.ReadKey(intercept: true, cancellationToken);
