public Size Draw(Point offset, BoxConstraint constraint, UIContext context)
{
var w = constraint.IsBoundedWidth ? constraint.MaxWidth : constraint.MinWidth;
var size = new Size(w, 1); // TODO yeuks
// sanity check
if (w < 1)
{
return(new Size(0, 0));
}
if (Input.CursorPosition < Input.StartVisiblePosition)
{
// cursor is behind start
Input.StartVisiblePosition = Input.CursorPosition;
}
else if (Input.Text.Length + 1 <= w)
{
// everything fits, just remove 'visible' back to 0
Input.StartVisiblePosition = 0;
}
else if (Input.CursorPosition - Input.StartVisiblePosition >= w)
{
// cursor is out of range ahoy!
// move start pos to match cursor
Input.StartVisiblePosition = Input.CursorPosition - w + 1;
}
else if (Input.Text.Length - Input.StartVisiblePosition + 1 < w)
{
// start pos is further right that it needs to be
Input.StartVisiblePosition = Input.Text.Length - w + 1;
}
var bounds = new Rectangle(offset, size);
if (Input.IsFocused)
{
// draw the cursor pos style if it has focus
var z = new Point(Input.CursorPosition - Input.StartVisiblePosition, 0);
if (CursorStyle != null)
{
context.Buffer.Modify(bounds, z, CursorStyle.Apply);
}
else
{
z.Offset(bounds.X, bounds.Y);
context.SetCursor(z, true);
}
}
// cut the text as approp
var output = Input.Text.Substring(Input.StartVisiblePosition);
var l = w > output.Length ? output.Length : w;
for (var x = 0; x < l; x++)
{
context.Buffer.Modify(bounds, new Point(x, 0), c =>
{
c.Char = output[x];
return(c);
});
}
return(constraint.Tighten(size).GetMinSize());
}