/// <summary>
/// Creates a boolean slot for expression that comes from originalCellNum, i.e.,
/// the value of the slot is <paramref name="expr" /> and the name is "_from{<paramref name="originalCellNum" />}", e.g., _from2
/// </summary>
internal BooleanProjectedSlot(BoolExpression expr, CqlIdentifiers identifiers, int originalCellNum)
{
m_expr = expr;
m_originalCell = new CellIdBoolean(identifiers, originalCellNum);
Debug.Assert(
!(expr.AsLiteral is CellIdBoolean) ||
BoolLiteral.EqualityComparer.Equals(expr.AsLiteral, m_originalCell), "Cellid boolean for the slot and cell number disagree");
}
protected override bool IsEqualTo(BoolLiteral right)
{
CellIdBoolean cellIdBoolean = right as CellIdBoolean;
if (cellIdBoolean == null)
{
return(false);
}
return(this.m_index == cellIdBoolean.m_index);
}
// Modifies _caseStatements and _topLevelWhereClause
private List<LeftCellWrapper> RemapFromVariables()
{
var usedCells = new List<LeftCellWrapper>();
// remap CellIdBooleans appearing in WHEN clauses and in topLevelWhereClause so the first used cell = 0, second = 1, etc.
// This ordering is exploited in CQL generation
var newNumber = 0;
var literalRemap = new Dictionary<BoolLiteral, BoolLiteral>(BoolLiteral.EqualityIdentifierComparer);
foreach (var leftCellWrapper in _context.AllWrappersForExtent)
{
if (_usedViews.Contains(leftCellWrapper.FragmentQuery))
{
usedCells.Add(leftCellWrapper);
var oldNumber = leftCellWrapper.OnlyInputCell.CellNumber;
if (newNumber != oldNumber)
{
literalRemap[new CellIdBoolean(_identifiers, oldNumber)] = new CellIdBoolean(_identifiers, newNumber);
}
newNumber++;
}
}
if (literalRemap.Count > 0)
{
// Remap _from literals in WHERE clause
_topLevelWhereClause = _topLevelWhereClause.RemapLiterals(literalRemap);
// Remap _from literals in case statements
var newCaseStatements = new Dictionary<MemberPath, CaseStatement>();
foreach (var entry in _caseStatements)
{
var newCaseStatement = new CaseStatement(entry.Key);
Debug.Assert(entry.Value.ElseValue == null);
foreach (var clause in entry.Value.Clauses)
{
newCaseStatement.AddWhenThen(clause.Condition.RemapLiterals(literalRemap), clause.Value);
}
newCaseStatements[entry.Key] = newCaseStatement;
}
_caseStatements = newCaseStatements;
}
return usedCells;
}