public static IReadOnlyList<IReadOnlyList<JoinAlias>> ExtractJoinAliases(IFromListItem join)
{
var tree = ExtractJoinAliasTree(join);
var ret = new List<List<JoinAlias>>();
foreach (var level in tree)
{
ret.Add(new List<JoinAlias>());
foreach (var rep in level.Items)
{
if (!ret.SelectMany(x => x).Any(x => x.Find == rep.Find))
{
//Agregar el rep:
var exAlias = ret.SelectMany(x => x).Where(x =>
CompareExpr.ExprEquals(x.Replace, rep.Rep) || CompareExpr.ExprEquals(x.Find, rep.Rep)
).Select(x => x.Alias).FirstOrDefault();
string alias;
if (exAlias != null)
{
alias = exAlias;
}
else
{
var memberAlias = ExtractMemberStr(rep.Rep);
alias = memberAlias;
//Si el alias esta repetido, le ponemos un numero consecutivo
for (var i = 1; i < 1000 && ret.SelectMany(x => x).Where(x => x.Alias == alias).Any(); i++)
{
alias = $"\"{memberAlias.Trim('"') + i}\"";
}
}
ret[ret.Count - 1].Add(new JoinAlias(rep.Find, rep.Rep, alias));
}
}
}
return ret;
}
/// <summary>
/// Remplaza todas las referencias a un elemento del WITH con un SqlTableRefRaw
/// </summary>
public static Expression SubqueryRawSubs(Expression subquery, ParameterExpression repParam)
{
if (subquery == null)
{
return(null);
}
//Sustituir todo param.X o param por el nombre:
var ret = ReplaceVisitor.Replace(subquery, expr =>
{
if (typeof(IFromListItemTarget).GetTypeInfo().IsAssignableFrom(expr.Type.GetTypeInfo()))
{
var selectInt = expr.Type.GetTypeInfo().ImplementedInterfaces.Concat(new[] { expr.Type }).Where(x => x.GetTypeInfo().IsGenericType&& x.GetGenericTypeDefinition() == typeof(IFromListItemTarget <>)).FirstOrDefault();
if (selectInt == null)
{
throw new ArgumentException("Debe de ser un IFromListItemTarget<T>");
}
var selectType = selectInt.GetTypeInfo().GenericTypeArguments[0];
if (expr is MemberExpression mem && CompareExpr.ExprEquals(mem.Expression, repParam))
{
return(RawSqlTableRefExpr(selectType, $"\"{mem.Member.Name}\""));
}
/// <summary>
/// Devuelve la cadena a la que corresponde la expresión o null en caso de que esta expresión no tenga ningún alias
/// </summary>
public static string ReplaceStringAliasMembers(Expression ex, IEnumerable<ExprStrRawSql> alias)
{
return alias.Where(x => CompareExpr.ExprEquals(x.Expr, ex)).Select(x => x.Sql).FirstOrDefault();
}