private ParseErrorExpression ExecuteAchievementComparison(ComparisonExpression comparison, InterpreterScope scope)
{
_equalityModifiers.Clear();
var context = scope.GetContext <TriggerBuilderContext>();
var insertIndex = context.Trigger.Count;
var left = comparison.Left;
var right = comparison.Right;
var op = GetRequirementOperator(comparison.Operation);
if (left.Type == ExpressionType.IntegerConstant)
{
if (right.Type == ExpressionType.IntegerConstant)
{
// comparing two constants, convert to always_true or always_false
var requirement = new Requirement
{
Left = new Field {
Type = FieldType.Value, Value = (uint)((IntegerConstantExpression)left).Value
},
Operator = op,
Right = new Field {
Type = FieldType.Value, Value = (uint)((IntegerConstantExpression)right).Value
},
};
if (Evaluate(requirement))
{
context.Trigger.Add(AlwaysTrueFunction.CreateAlwaysTrueRequirement());
}
else
{
context.Trigger.Add(AlwaysFalseFunction.CreateAlwaysFalseRequirement());
}
return(null);
}
// swap the operands and operator so the constant is on the right
var temp = left;
left = right;
right = temp;
op = GetReversedRequirementOperator(op);
}
var error = ExecuteAchievementExpression(left, scope);
if (error != null)
{
return(error);
}
var integerRight = right as IntegerConstantExpression;
if (integerRight != null)
{
int newValue = integerRight.Value;
// SubSource of a memory accessor may cause overflow - if comparing for less than,
// modifiers should not be merged into the compare target
if (_equalityModifiers.Count > 0 &&
(op == RequirementOperator.LessThan || op == RequirementOperator.LessThanOrEqual))
{
bool hasSubSource = false;
for (int i = context.Trigger.Count - 2; i >= 0; i++)
{
var requirementType = context.Trigger.ElementAt(i).Type;
if (requirementType == RequirementType.SubSource)
{
hasSubSource = true;
break;
}
else if (requirementType != RequirementType.AddSource &&
requirementType != RequirementType.AddHits)
{
break;
}
}
if (hasSubSource)
{
var last = context.Trigger.Last();
context.Trigger.Remove(last);
foreach (var modifier in _equalityModifiers)
{
if (modifier.Operation != MathematicOperation.Subtract && modifier.Operation != MathematicOperation.Add)
{
return(new ParseErrorExpression("Cannot normalize expression containing SubSource", left));
}
context.Trigger.Add(new Requirement
{
Type = (modifier.Operation == MathematicOperation.Subtract) ? RequirementType.AddSource : RequirementType.SubSource,
Left = new Field {
Type = FieldType.Value, Value = (uint)modifier.Amount
},
Operator = RequirementOperator.None,
Right = new Field()
});
}
context.Trigger.Add(last);
_equalityModifiers.Clear();
}
}
while (_equalityModifiers.Count > 0)
{
var originalValue = newValue;
var modifier = _equalityModifiers.Pop();
newValue = modifier.Apply(newValue);
var restoredValue = modifier.Remove(newValue);
switch (op)
{
case RequirementOperator.Equal:
if (restoredValue != originalValue)
{
return(new ParseErrorExpression("Result can never be true using integer math", comparison));
}
break;
case RequirementOperator.NotEqual:
if (restoredValue != originalValue)
{
return(new ParseErrorExpression("Result is always true using integer math", comparison));
}
break;
case RequirementOperator.GreaterThanOrEqual:
if (restoredValue != originalValue)
{
op = RequirementOperator.GreaterThan;
}
break;
}
}
var requirement = context.LastRequirement;
requirement.Operator = op;
requirement.Right = new Field {
Size = requirement.Left.Size, Type = FieldType.Value, Value = (uint)newValue
};
}
else
{
var leftModifiers = new Stack <ValueModifier>(_equalityModifiers.Reverse());
_equalityModifiers.Clear();
error = ExecuteAchievementExpression(right, scope);
if (error != null)
{
return(error);
}
if (leftModifiers.Count > 0 || _equalityModifiers.Count > 0)
{
var rightValue = 1234567;
var leftValue = rightValue;
while (leftModifiers.Count > 0)
{
var modifier = leftModifiers.Pop();
leftValue = ValueModifier.Apply(leftValue, MathematicExpression.GetOppositeOperation(modifier.Operation), modifier.Amount);
}
while (_equalityModifiers.Count > 0)
{
var modifier = _equalityModifiers.Pop();
rightValue = ValueModifier.Apply(rightValue, MathematicExpression.GetOppositeOperation(modifier.Operation), modifier.Amount);
}
var diff = leftValue - rightValue;
if (diff != 0)
{
var modifier = new Requirement();
if (diff < 0)
{
modifier.Left = new Field {
Type = FieldType.Value, Value = (uint)(-diff)
};
modifier.Type = RequirementType.SubSource;
}
else
{
modifier.Left = new Field {
Type = FieldType.Value, Value = (uint)diff
};
modifier.Type = RequirementType.AddSource;
}
((IList <Requirement>)context.Trigger).Insert(insertIndex, modifier);
}
}
var extraRequirement = context.LastRequirement;
context.Trigger.Remove(extraRequirement);
var requirement = context.LastRequirement;
if (requirement != null)
{
requirement.Operator = op;
requirement.Right = extraRequirement.Left;
}
}
return(null);
}
private ParseErrorExpression ExecuteAchievementMathematic(MathematicExpression mathematic, InterpreterScope scope)
{
var left = mathematic.Left;
var operation = mathematic.Operation;
var context = scope.GetContext <TriggerBuilderContext>();
ParseErrorExpression error;
ExpressionBase right;
if (!mathematic.Right.ReplaceVariables(scope, out right))
{
return((ParseErrorExpression)right);
}
if (operation == MathematicOperation.Subtract && (right is FunctionCallExpression || right is MathematicExpression))
{
// if subtracting a non-integer, swap the order to perform a SubSource
var newEqualityModifiers = new Stack <ValueModifier>();
var oldEqualityModifiers = _equalityModifiers;
_equalityModifiers = newEqualityModifiers;
var requirements = new List <Requirement>();
var innerContext = new TriggerBuilderContext()
{
Trigger = requirements
};
var innerScope = new InterpreterScope(scope)
{
Context = innerContext
};
// generate the condition for the right side
error = ExecuteAchievementExpression(right, innerScope);
_equalityModifiers = oldEqualityModifiers;
if (error != null)
{
return(error);
}
foreach (var requirement in requirements)
{
switch (requirement.Type)
{
case RequirementType.None:
case RequirementType.AddSource:
requirement.Type = RequirementType.SubSource;
break;
case RequirementType.SubSource:
requirement.Type = RequirementType.AddSource;
break;
default:
return(new ParseErrorExpression("Cannot normalize expression for negation", mathematic));
}
context.Trigger.Add(requirement);
}
foreach (var modifier in newEqualityModifiers)
{
switch (modifier.Operation)
{
case MathematicOperation.Add:
_equalityModifiers.Push(new ValueModifier(MathematicOperation.Subtract, modifier.Amount));
break;
case MathematicOperation.Subtract:
_equalityModifiers.Push(new ValueModifier(MathematicOperation.Add, modifier.Amount));
break;
default:
return(new ParseErrorExpression("Cannot normalize expression for negation", mathematic));
}
}
right = mathematic.Left;
operation = MathematicOperation.Add;
}
else
{
// generate the condition for the first expression
error = ExecuteAchievementExpression(left, scope);
if (error != null)
{
return(error);
}
}
var integerOperand = right as IntegerConstantExpression;
if (integerOperand != null)
{
var oppositeOperation = MathematicExpression.GetOppositeOperation(operation);
if (oppositeOperation == MathematicOperation.None)
{
return(new ParseErrorExpression(String.Format("Cannot normalize expression to eliminate {0}", MathematicExpression.GetOperatorType(mathematic.Operation)), mathematic));
}
var priority = MathematicExpression.GetPriority(mathematic.Operation);
if (priority != MathematicPriority.Add)
{
if (context.Trigger.Count > 1)
{
var previousRequirementType = context.Trigger.ElementAt(context.Trigger.Count - 2).Type;
if (previousRequirementType == RequirementType.AddSource || previousRequirementType == RequirementType.SubSource)
{
return(new ParseErrorExpression(String.Format("Cannot normalize expression to eliminate {0}", MathematicExpression.GetOperatorType(mathematic.Operation)), mathematic));
}
}
if (_equalityModifiers.Any(e => MathematicExpression.GetPriority(e.Operation) != priority))
{
return(new ParseErrorExpression(String.Format("Cannot normalize expression to eliminate {0}", MathematicExpression.GetOperatorType(mathematic.Operation)), mathematic));
}
}
_equalityModifiers.Push(new ValueModifier(oppositeOperation, integerOperand.Value));
return(null);
}
if (operation == MathematicOperation.Add)
{
foreach (var modifier in _equalityModifiers)
{
if (MathematicExpression.GetPriority(modifier.Operation) != MathematicPriority.Add)
{
return(new ParseErrorExpression(String.Format("Cannot normalize expression to eliminate {0}", MathematicExpression.GetOperatorType(MathematicExpression.GetOppositeOperation(modifier.Operation))), mathematic));
}
}
// adding two memory accessors - make sure previous is AddSource or SubSource
if (context.LastRequirement.Type != RequirementType.SubSource)
{
context.LastRequirement.Type = RequirementType.AddSource;
context.LastRequirement.Operator = RequirementOperator.None;
context.LastRequirement.Right = new Field();
}
}
else
{
return(new ParseErrorExpression(String.Format("Cannot normalize expression to eliminate {0}", MathematicExpression.GetOperatorType(mathematic.Operation)), mathematic));
}
// generate the condition for the second expression
error = ExecuteAchievementExpression(right, scope);
if (error != null)
{
error = new ParseErrorExpression(error.Message, mathematic);
}
return(error);
}