/*--------------------------------------------------------------------
 * Symbols referenced in this file:
 * - makeDefElemExtended
 * - makeDefElem
 * - makeTypeNameFromNameList
 * - makeAlias
 * - makeGroupingSet
 * - makeTypeName
 * - makeFuncCall
 * - makeSimpleA_Expr
 * - makeA_Expr
 * - makeRangeVar
 * - makeBoolExpr
 *--------------------------------------------------------------------
 */

/*-------------------------------------------------------------------------
 *
 * makefuncs.c
 *	  creator functions for primitive nodes. The functions here are for
 *	  the most frequently created nodes.
 *
 * Portions Copyright (c) 1996-2015, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 *
 * IDENTIFICATION
 *	  src/backend/nodes/makefuncs.c
 *
 *-------------------------------------------------------------------------
 */
#include "postgres.h"

#include "catalog/pg_class.h"
#include "catalog/pg_type.h"
#include "fmgr.h"
#include "nodes/makefuncs.h"
#include "nodes/nodeFuncs.h"
#include "utils/lsyscache.h"


/*
 * makeA_Expr -
 *		makes an A_Expr node
 */
A_Expr *
makeA_Expr(A_Expr_Kind kind, List *name,
		   Node *lexpr, Node *rexpr, int location)
{
	A_Expr	   *a = makeNode(A_Expr);

	a->kind = kind;
	a->name = name;
	a->lexpr = lexpr;
	a->rexpr = rexpr;
	a->location = location;
	return a;
}

/*
 * makeSimpleA_Expr -
 *		As above, given a simple (unqualified) operator name
 */
A_Expr *
makeSimpleA_Expr(A_Expr_Kind kind, char *name,
				 Node *lexpr, Node *rexpr, int location)
{
	A_Expr	   *a = makeNode(A_Expr);

	a->kind = kind;
	a->name = list_make1(makeString((char *) name));
	a->lexpr = lexpr;
	a->rexpr = rexpr;
	a->location = location;
	return a;
}

/*
 * makeVar -
 *	  creates a Var node
 */


/*
 * makeVarFromTargetEntry -
 *		convenience function to create a same-level Var node from a
 *		TargetEntry
 */


/*
 * makeWholeRowVar -
 *	  creates a Var node representing a whole row of the specified RTE
 *
 * A whole-row reference is a Var with varno set to the correct range
 * table entry, and varattno == 0 to signal that it references the whole
 * tuple.  (Use of zero here is unclean, since it could easily be confused
 * with error cases, but it's not worth changing now.)  The vartype indicates
 * a rowtype; either a named composite type, or RECORD.  This function
 * encapsulates the logic for determining the correct rowtype OID to use.
 *
 * If allowScalar is true, then for the case where the RTE is a single function
 * returning a non-composite result type, we produce a normal Var referencing
 * the function's result directly, instead of the single-column composite
 * value that the whole-row notation might otherwise suggest.
 */


/*
 * makeTargetEntry -
 *	  creates a TargetEntry node
 */


/*
 * flatCopyTargetEntry -
 *	  duplicate a TargetEntry, but don't copy substructure
 *
 * This is commonly used when we just want to modify the resno or substitute
 * a new expression.
 */


/*
 * makeFromExpr -
 *	  creates a FromExpr node
 */


/*
 * makeConst -
 *	  creates a Const node
 */


/*
 * makeNullConst -
 *	  creates a Const node representing a NULL of the specified type/typmod
 *
 * This is a convenience routine that just saves a lookup of the type's
 * storage properties.
 */


/*
 * makeBoolConst -
 *	  creates a Const node representing a boolean value (can be NULL too)
 */


/*
 * makeBoolExpr -
 *	  creates a BoolExpr node
 */
Expr *
makeBoolExpr(BoolExprType boolop, List *args, int location)
{
	BoolExpr   *b = makeNode(BoolExpr);

	b->boolop = boolop;
	b->args = args;
	b->location = location;

	return (Expr *) b;
}

/*
 * makeAlias -
 *	  creates an Alias node
 *
 * NOTE: the given name is copied, but the colnames list (if any) isn't.
 */
Alias *
makeAlias(const char *aliasname, List *colnames)
{
	Alias	   *a = makeNode(Alias);

	a->aliasname = pstrdup(aliasname);
	a->colnames = colnames;

	return a;
}

/*
 * makeRelabelType -
 *	  creates a RelabelType node
 */


/*
 * makeRangeVar -
 *	  creates a RangeVar node (rather oversimplified case)
 */
RangeVar *
makeRangeVar(char *schemaname, char *relname, int location)
{
	RangeVar   *r = makeNode(RangeVar);

	r->catalogname = NULL;
	r->schemaname = schemaname;
	r->relname = relname;
	r->inhOpt = INH_DEFAULT;
	r->relpersistence = RELPERSISTENCE_PERMANENT;
	r->alias = NULL;
	r->location = location;

	return r;
}

/*
 * makeTypeName -
 *	build a TypeName node for an unqualified name.
 *
 * typmod is defaulted, but can be changed later by caller.
 */
TypeName *
makeTypeName(char *typnam)
{
	return makeTypeNameFromNameList(list_make1(makeString(typnam)));
}

/*
 * makeTypeNameFromNameList -
 *	build a TypeName node for a String list representing a qualified name.
 *
 * typmod is defaulted, but can be changed later by caller.
 */
TypeName *
makeTypeNameFromNameList(List *names)
{
	TypeName   *n = makeNode(TypeName);

	n->names = names;
	n->typmods = NIL;
	n->typemod = -1;
	n->location = -1;
	return n;
}

/*
 * makeTypeNameFromOid -
 *	build a TypeName node to represent a type already known by OID/typmod.
 */


/*
 * makeFuncExpr -
 *	build an expression tree representing a function call.
 *
 * The argument expressions must have been transformed already.
 */


/*
 * makeDefElem -
 *	build a DefElem node
 *
 * This is sufficient for the "typical" case with an unqualified option name
 * and no special action.
 */
DefElem *
makeDefElem(char *name, Node *arg)
{
	DefElem    *res = makeNode(DefElem);

	res->defnamespace = NULL;
	res->defname = name;
	res->arg = arg;
	res->defaction = DEFELEM_UNSPEC;
	res->location = -1;

	return res;
}

/*
 * makeDefElemExtended -
 *	build a DefElem node with all fields available to be specified
 */
DefElem *
makeDefElemExtended(char *nameSpace, char *name, Node *arg,
					DefElemAction defaction, int location)
{
	DefElem    *res = makeNode(DefElem);

	res->defnamespace = nameSpace;
	res->defname = name;
	res->arg = arg;
	res->defaction = defaction;
	res->location = location;

	return res;
}

/*
 * makeFuncCall -
 *
 * Initialize a FuncCall struct with the information every caller must
 * supply.  Any non-default parameters have to be inserted by the caller.
 */
FuncCall *
makeFuncCall(List *name, List *args, int location)
{
	FuncCall   *n = makeNode(FuncCall);

	n->funcname = name;
	n->args = args;
	n->agg_order = NIL;
	n->agg_filter = NULL;
	n->agg_within_group = false;
	n->agg_star = false;
	n->agg_distinct = false;
	n->func_variadic = false;
	n->over = NULL;
	n->location = location;
	return n;
}

/*
 * makeGroupingSet
 *
 */
GroupingSet *
makeGroupingSet(GroupingSetKind kind, List *content, int location)
{
	GroupingSet *n = makeNode(GroupingSet);

	n->kind = kind;
	n->content = content;
	n->location = location;
	return n;
}