/*-------------------------------------------------------------------------
 *
 * rewriteManip.h
 *		Querytree manipulation subroutines for query rewriter.
 *
 *
 * Portions Copyright (c) 1996-2013, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * src/include/rewrite/rewriteManip.h
 *
 *-------------------------------------------------------------------------
 */
#ifndef REWRITEMANIP_H
#define REWRITEMANIP_H

#include "nodes/parsenodes.h"


typedef struct replace_rte_variables_context replace_rte_variables_context;

typedef Node *(*replace_rte_variables_callback) (Var *var,
									 replace_rte_variables_context *context);

struct replace_rte_variables_context
{
	replace_rte_variables_callback callback;	/* callback function */
	void	   *callback_arg;	/* context data for callback function */
	int			target_varno;	/* RTE index to search for */
	int			sublevels_up;	/* (current) nesting depth */
	bool		inserted_sublink;		/* have we inserted a SubLink? */
};

typedef enum ReplaceVarsNoMatchOption
{
	REPLACEVARS_REPORT_ERROR,	/* throw error if no match */
	REPLACEVARS_CHANGE_VARNO,	/* change the Var's varno, nothing else */
	REPLACEVARS_SUBSTITUTE_NULL /* replace with a NULL Const */
} ReplaceVarsNoMatchOption;


extern void OffsetVarNodes(Node *node, int offset, int sublevels_up);
extern void ChangeVarNodes(Node *node, int old_varno, int new_varno,
			   int sublevels_up);
extern void IncrementVarSublevelsUp(Node *node, int delta_sublevels_up,
						int min_sublevels_up);
extern void IncrementVarSublevelsUp_rtable(List *rtable,
							   int delta_sublevels_up, int min_sublevels_up);

extern bool rangeTableEntry_used(Node *node, int rt_index,
					 int sublevels_up);
extern bool attribute_used(Node *node, int rt_index, int attno,
			   int sublevels_up);

extern Query *getInsertSelectQuery(Query *parsetree, Query ***subquery_ptr);

extern void AddQual(Query *parsetree, Node *qual);
extern void AddInvertedQual(Query *parsetree, Node *qual);

extern bool contain_aggs_of_level(Node *node, int levelsup);
extern int	locate_agg_of_level(Node *node, int levelsup);
extern bool contain_windowfuncs(Node *node);
extern int	locate_windowfunc(Node *node);
extern bool checkExprHasSubLink(Node *node);

extern Node *replace_rte_variables(Node *node,
					  int target_varno, int sublevels_up,
					  replace_rte_variables_callback callback,
					  void *callback_arg,
					  bool *outer_hasSubLinks);
extern Node *replace_rte_variables_mutator(Node *node,
							  replace_rte_variables_context *context);

extern Node *map_variable_attnos(Node *node,
					int target_varno, int sublevels_up,
					const AttrNumber *attno_map, int map_length,
					bool *found_whole_row);

extern Node *ReplaceVarsFromTargetList(Node *node,
						  int target_varno, int sublevels_up,
						  RangeTblEntry *target_rte,
						  List *targetlist,
						  ReplaceVarsNoMatchOption nomatch_option,
						  int nomatch_varno,
						  bool *outer_hasSubLinks);

#endif   /* REWRITEMANIP_H */
