/// <summary>
/// Merge in the parameters from the incoming exp and renames them if there are any collisions.
///
/// Returns a new instance of exp with the parameters replaced.
/// </summary>
/// <param name="exp"></param>
/// <returns></returns>
public ExpressionText MergeParameterMapping(ExpressionText exp)
{
// Para evitar que la expresión original quede manipulada la clonamos.
// No usamos JsonClone clone por rendimiento
// var expSource = ExtensionHelpers.JsonClone(exp);
var expSource = new ExpressionText()
{
Parameters = new Dictionary <string, string>(exp.Parameters ?? new Dictionary <string, string>()),
InternalExpression = exp.InternalExpression,
Arguments = new Dictionary <string, object>(exp.Arguments ?? new Dictionary <string, object>()),
ClrType = exp.ClrType
};
if (exp.Parameters == null)
{
return(expSource);
}
this.Parameters = this.Parameters ?? new Dictionary <string, string>();
foreach (var key in expSource.Parameters.Keys.ToList())
{
var keyName = this.FindFreeParameterPlaceholder(this, expSource, key);
expSource.ReplaceParameterPlaceholder(key, keyName);
this.Parameters[keyName] = expSource.Parameters[keyName];
}
return(expSource);
}
/// <summary>
/// Transform a lambda expression into it's text representation
/// </summary>
/// <param name="expression"></param>
/// <returns></returns>
public ExpressionText GetExpressionText(
Expression expression)
{
this.Arguments = new Dictionary <string, object>();
this.Parameters = new Dictionary <string, string>();
this.TempParameters = new Dictionary <string, ParameterExpression>();
ExpressionText result = new ExpressionText();
var exp = this.VisitExpression(expression, null);
result.InternalExpression = exp.Text;
result.Arguments = this.Arguments;
result.Parameters = this.Parameters;
result.Parameters2 = this.TempParameters;
result.ClrType = exp.ClrType?.FullName;
return(result);
}
/// <summary>
///
/// </summary>
/// <param name="exp1"></param>
/// <param name="exp2"></param>
/// <param name="proposal"></param>
/// <param name="freeIfMatchingValue"></param>
/// <returns></returns>
public string FindFreeParameterPlaceholder(
ExpressionText exp1,
ExpressionText exp2,
string proposal,
bool freeIfMatchingValue = true)
{
int x = 0;
string key = $"{proposal}";
if (exp1.Parameters == null || !exp1.Parameters.ContainsKey(key))
{
return(key);
}
while (true)
{
// Si la proyección es igual, podemos sobrescribir
if (freeIfMatchingValue &&
exp1.Parameters.ContainsKey(key) &&
exp2.Parameters.ContainsKey(key) &&
exp1.Parameters[key] == exp2.Parameters[key])
{
return(key);
}
if (exp1.Parameters == null || exp2.Parameters == null)
{
return(key);
}
if (!exp1.Parameters.ContainsKey(key) && !exp2.Parameters.ContainsKey(key))
{
return(key);
}
key = $"{proposal}_{x}";
x++;
}
}
