IEnumerable <ParserNode> NavigateCell(ParserNavigationDirectionEnum direction, bool shiftDown, bool keepSelections)
{
var startColumn = parent.children.IndexOf(this);
var startRow = parent.parent.children.IndexOf(parent);
var endColumn = startColumn;
var endRow = startRow;
switch (direction)
{
case ParserNavigationDirectionEnum.Up: endRow -= 1; break;
case ParserNavigationDirectionEnum.Down: endRow += 1; break;
case ParserNavigationDirectionEnum.Left: endColumn -= 1; break;
case ParserNavigationDirectionEnum.Right: endColumn += 1; break;
case ParserNavigationDirectionEnum.Home: endColumn = 0; break;
case ParserNavigationDirectionEnum.End: endColumn = int.MaxValue; break;
case ParserNavigationDirectionEnum.PgUp: endRow = 0; break;
case ParserNavigationDirectionEnum.PgDn: endRow = int.MaxValue; break;
case ParserNavigationDirectionEnum.Row: startColumn = 0; endColumn = int.MaxValue; break;
case ParserNavigationDirectionEnum.Column: startRow = 0; endRow = int.MaxValue; break;
}
if (!shiftDown)
{
if (keepSelections)
{
endRow = Math.Max(0, Math.Min(endRow, parent.parent.children.Count - 1));
endColumn = Math.Max(0, Math.Min(endColumn, parent.parent.children[endRow].children.Count - 1));
}
if ((endRow >= 0) && (endRow < parent.parent.children.Count))
{
if ((endColumn >= 0) && (endColumn < parent.parent.children[endRow].children.Count))
{
yield return(parent.parent.children[endRow].children[endColumn]);
}
}
yield break;
}
var minRow = Math.Max(0, Math.Min(startRow, endRow));
var minColumn = Math.Max(0, Math.Min(startColumn, endColumn));
var maxRow = Math.Min(parent.parent.children.Count - 1, Math.Max(startRow, endRow));
var maxColumn = Math.Max(startColumn, endColumn); // Can't force any upper bound; different rows could have different numbers of columns
for (var row = minRow; row <= maxRow; ++row)
{
for (var column = minColumn; column <= Math.Min(parent.parent.children[row].children.Count - 1, maxColumn); ++column)
{
yield return(parent.parent.children[row].children[column]);
}
}
}
public IEnumerable <ParserNode> Navigate(ParserNavigationDirectionEnum direction, bool shiftDown, bool keepSelections)
{
switch (ParserNavigationType)
{
case ParserNavigationTypeEnum.Regular: return(NavigateRegular(direction, shiftDown, keepSelections));
case ParserNavigationTypeEnum.FirstChild: return(NavigateFirstChild());
case ParserNavigationTypeEnum.Cell: return(NavigateCell(direction, shiftDown, keepSelections));
default: throw new ArgumentException($"Invalid {nameof(ParserNavigationType)}");
}
}
public IEnumerable<ParserNode> Navigate(ParserNavigationDirectionEnum direction, bool shiftDown)
{
switch (ParserNavigationType)
{
case ParserNavigationTypeEnum.Regular: return NavigateRegular(direction, shiftDown);
case ParserNavigationTypeEnum.FirstChild: return NavigateFirstChild();
case ParserNavigationTypeEnum.Cell: return NavigateCell(direction, shiftDown);
default: throw new ArgumentException($"Invalid {nameof(ParserNavigationType)}");
}
}
IEnumerable<ParserNode> NavigateCell(ParserNavigationDirectionEnum direction, bool shiftDown)
{
var startColumn = parent.children.IndexOf(this);
var startRow = parent.parent.children.IndexOf(parent);
var endColumn = startColumn;
var endRow = startRow;
switch (direction)
{
case ParserNavigationDirectionEnum.Up: endRow -= 1; break;
case ParserNavigationDirectionEnum.Down: endRow += 1; break;
case ParserNavigationDirectionEnum.Left: endColumn -= 1; break;
case ParserNavigationDirectionEnum.Right: endColumn += 1; break;
case ParserNavigationDirectionEnum.Home: endColumn = 0; break;
case ParserNavigationDirectionEnum.End: endColumn = int.MaxValue; break;
case ParserNavigationDirectionEnum.PgUp: endRow = 0; break;
case ParserNavigationDirectionEnum.PgDn: endRow = int.MaxValue; break;
case ParserNavigationDirectionEnum.Row: startColumn = 0; endColumn = int.MaxValue; break;
case ParserNavigationDirectionEnum.Column: startRow = 0; endRow = int.MaxValue; break;
}
if (!shiftDown)
{
var row = Math.Max(0, Math.Min(endRow, parent.parent.children.Count - 1));
var column = Math.Max(0, Math.Min(endColumn, parent.parent.children[row].children.Count - 1));
yield return parent.parent.children[row].children[column];
yield break;
}
var minRow = Math.Max(0, Math.Min(startRow, endRow));
var minColumn = Math.Max(0, Math.Min(startColumn, endColumn));
var maxRow = Math.Min(parent.parent.children.Count - 1, Math.Max(startRow, endRow));
var maxColumn = Math.Max(startColumn, endColumn); // Can't force any upper bound; different rows could have different numbers of columns
for (var row = minRow; row <= maxRow; ++row)
for (var column = minColumn; column <= Math.Min(parent.parent.children[row].children.Count - 1, maxColumn); ++column)
yield return parent.parent.children[row].children[column];
}
IEnumerable<ParserNode> NavigateRegular(ParserNavigationDirectionEnum direction, bool shiftDown)
{
switch (direction)
{
case ParserNavigationDirectionEnum.Up:
case ParserNavigationDirectionEnum.Down:
{
if (shiftDown)
yield return this;
var index = parent?.children.IndexOf(this);
if ((index == -1) || (index == null))
{
yield return this;
yield break;
}
var offset = direction == ParserNavigationDirectionEnum.Up ? -1 : 1;
index = Math.Max(0, Math.Min(index.Value + offset, parent.children.Count - 1));
yield return parent.children[index.Value];
}
break;
case ParserNavigationDirectionEnum.Left:
yield return parent == null ? this : parent;
break;
case ParserNavigationDirectionEnum.Right:
if (!children.Any())
yield return this;
foreach (var child in children)
{
yield return child;
if (!shiftDown)
break;
}
break;
case ParserNavigationDirectionEnum.Row:
case ParserNavigationDirectionEnum.Column:
if (parent == null)
{
yield return this;
break;
}
foreach (var child in parent.children)
yield return child;
break;
case ParserNavigationDirectionEnum.Home:
case ParserNavigationDirectionEnum.PgUp:
{
if (parent == null)
{
yield return this;
yield break;
}
var index = parent.children.IndexOf(this);
if (!shiftDown)
yield return parent.children.First();
else
foreach (var child in parent.children.Take(index + 1))
yield return child;
}
break;
case ParserNavigationDirectionEnum.End:
case ParserNavigationDirectionEnum.PgDn:
{
if (parent == null)
{
yield return this;
yield break;
}
var index = parent.children.IndexOf(this);
if (!shiftDown)
yield return parent.children.Last();
else
foreach (var child in parent.children.Skip(index))
yield return child;
}
break;
default: yield return this; break;
}
}
IEnumerable <ParserNode> NavigateRegular(ParserNavigationDirectionEnum direction, bool shiftDown, bool keepSelections)
{
switch (direction)
{
case ParserNavigationDirectionEnum.Up:
case ParserNavigationDirectionEnum.Down:
{
if (shiftDown)
{
yield return(this);
}
var index = parent?.children.IndexOf(this) ?? -1;
if (index == -1)
{
if (keepSelections)
{
yield return(this);
}
break;
}
index += direction == ParserNavigationDirectionEnum.Up ? -1 : 1;
if (keepSelections)
{
index = Math.Max(0, Math.Min(index, parent.children.Count - 1));
}
if ((index >= 0) && (index < parent.children.Count))
{
yield return(parent.children[index]);
}
}
break;
case ParserNavigationDirectionEnum.Left:
if ((parent != null) || (keepSelections))
{
yield return(parent ?? this);
}
break;
case ParserNavigationDirectionEnum.Right:
if ((keepSelections) && (!children.Any()))
{
yield return(this);
}
foreach (var child in children)
{
yield return(child);
if (!shiftDown)
{
break;
}
}
break;
case ParserNavigationDirectionEnum.Row:
case ParserNavigationDirectionEnum.Column:
if (parent == null)
{
if (keepSelections)
{
yield return(this);
}
break;
}
foreach (var child in parent.children)
{
yield return(child);
}
break;
case ParserNavigationDirectionEnum.Home:
case ParserNavigationDirectionEnum.PgUp:
{
if (parent == null)
{
if (keepSelections)
{
yield return(this);
}
break;
}
var index = parent.children.IndexOf(this);
if (!shiftDown)
{
yield return(parent.children.First());
}
else
{
foreach (var child in parent.children.Take(index + 1))
{
yield return(child);
}
}
}
break;
case ParserNavigationDirectionEnum.End:
case ParserNavigationDirectionEnum.PgDn:
{
if (parent == null)
{
if (keepSelections)
{
yield return(this);
}
break;
}
var index = parent.children.IndexOf(this);
if (!shiftDown)
{
yield return(parent.children.Last());
}
else
{
foreach (var child in parent.children.Skip(index))
{
yield return(child);
}
}
}
break;
default:
if (keepSelections)
{
yield return(this);
}
break;
}
}