#include "Python.h"
#include "postgres.h"
#include "access/relscan.h"
#include "catalog/pg_foreign_server.h"
#include "catalog/pg_foreign_table.h"
#include "catalog/pg_type.h"
#include "commands/defrem.h"
#include "commands/explain.h"
#include "foreign/fdwapi.h"
#include "foreign/foreign.h"
#include "funcapi.h"
#include "lib/stringinfo.h"
#include "nodes/bitmapset.h"
#include "nodes/makefuncs.h"
#include "nodes/pg_list.h"
#include "nodes/relation.h"
#include "utils/builtins.h"
#include "utils/syscache.h"

#ifndef PG_MULTICORN_H
#define PG_MULTICORN_H

/* Data structures */

typedef struct CacheEntry
{
	Oid			hashkey;
	PyObject   *value;
	List	   *options;
	List	   *columns;
	int			xact_depth;
	/* Keep the "options" and "columns" in a specific context to avoid leaks. */
	MemoryContext cacheContext;
}	CacheEntry;


typedef struct ConversionInfo
{
	char	   *attrname;
	FmgrInfo   *attinfunc;
	FmgrInfo   *attoutfunc;
	Oid			atttypoid;
	Oid			attioparam;
	int32		atttypmod;
	int			attnum;
	bool		is_array;
	int			attndims;
	bool		need_quote;
}	ConversionInfo;


typedef struct MulticornPlanState
{
	Oid			foreigntableid;
	AttrNumber	numattrs;
	PyObject   *fdw_instance;
	List	   *target_list;
	List	   *qual_list;
	int			startupCost;
	ConversionInfo **cinfos;
	List	   *pathkeys; /* list of MulticornDeparsedSortGroup) */
}	MulticornPlanState;

typedef struct MulticornExecState
{
	/* instance and iterator */
	PyObject   *fdw_instance;
	PyObject   *p_iterator;
	/* Information carried from the plan phase. */
	List	   *target_list;
	List	   *qual_list;
	Datum	   *values;
	bool	   *nulls;
	ConversionInfo **cinfos;
	/* Common buffer to avoid repeated allocations */
	StringInfo	buffer;
	AttrNumber	rowidAttno;
	char	   *rowidAttrName;
	List	   *pathkeys; /* list of MulticornDeparsedSortGroup) */
}	MulticornExecState;

typedef struct MulticornModifyState
{
	ConversionInfo **cinfos;
	ConversionInfo **resultCinfos;
	PyObject   *fdw_instance;
	StringInfo	buffer;
	AttrNumber	rowidAttno;
	char	   *rowidAttrName;
	ConversionInfo *rowidCinfo;
}	MulticornModifyState;


typedef struct MulticornBaseQual
{
	AttrNumber	varattno;
	NodeTag		right_type;
	Oid			typeoid;
	char	   *opname;
	bool		isArray;
	bool		useOr;
}	MulticornBaseQual;

typedef struct MulticornConstQual
{
	MulticornBaseQual base;
	Datum		value;
	bool		isnull;
}	MulticornConstQual;

typedef struct MulticornVarQual
{
	MulticornBaseQual base;
	AttrNumber	rightvarattno;
}	MulticornVarQual;

typedef struct MulticornParamQual
{
	MulticornBaseQual base;
	Expr	   *expr;
}	MulticornParamQual;

typedef struct MulticornDeparsedSortGroup
{
	Name 			attname;
	int				attnum;
	bool			reversed;
	bool			nulls_first;
	Name			collate;
	PathKey	*key;
} MulticornDeparsedSortGroup;

/* errors.c */
void		errorCheck(void);

/* python.c */
PyObject   *pgstringToPyUnicode(const char *string);
char	  **pyUnicodeToPgString(PyObject *pyobject);

PyObject   *getInstance(Oid foreigntableid);
PyObject   *qualToPyObject(Expr *expr, PlannerInfo *root);
PyObject   *getClassString(const char *className);
PyObject   *execute(ForeignScanState *state, ExplainState *es);
void pythonResultToTuple(PyObject *p_value,
					TupleTableSlot *slot,
					ConversionInfo ** cinfos,
					StringInfo buffer);
PyObject   *tupleTableSlotToPyObject(TupleTableSlot *slot, ConversionInfo ** cinfos);
char	   *getRowIdColumn(PyObject *fdw_instance);
PyObject   *optionsListToPyDict(List *options);
const char *getPythonEncodingName(void);

void getRelSize(MulticornPlanState * state,
		PlannerInfo *root,
		double *rows,
		int *width);

List	   *pathKeys(MulticornPlanState * state);

List	   *canSort(MulticornPlanState * state, List *deparsed);

CacheEntry *getCacheEntry(Oid foreigntableid);
UserMapping *multicorn_GetUserMapping(Oid userid, Oid serverid);


/* Hash table mapping oid to fdw instances */
extern PGDLLIMPORT HTAB *InstancesHash;


/* query.c */
void extractRestrictions(Relids base_relids,
					Expr *node,
					List **quals);
List	   *extractColumns(List *reltargetlist, List *restrictinfolist);
void initConversioninfo(ConversionInfo ** cinfo,
		AttInMetadata *attinmeta);

Value *colnameFromVar(Var *var, PlannerInfo *root,
		MulticornPlanState * state);

void computeDeparsedSortGroup(List *deparsed, MulticornPlanState *planstate,
		List **apply_pathkeys,
		List **deparsed_pathkeys);

List	*findPaths(PlannerInfo *root, RelOptInfo *baserel, List *possiblePaths,
		int startupCost,
		MulticornPlanState *state,
		List *apply_pathkeys, List *deparsed_pathkeys);

List        *deparse_sortgroup(PlannerInfo *root, Oid foreigntableid, RelOptInfo *rel);

PyObject   *datumToPython(Datum node, Oid typeoid, ConversionInfo * cinfo);

List	*serializeDeparsedSortGroup(List *pathkeys);
List	*deserializeDeparsedSortGroup(List *items);

#endif   /* PG_MULTICORN_H */

char	   *PyUnicode_AsPgString(PyObject *p_unicode);

#if PY_MAJOR_VERSION >= 3
PyObject   *PyString_FromString(const char *s);
PyObject   *PyString_FromStringAndSize(const char *s, Py_ssize_t size);
char	   *PyString_AsString(PyObject *unicode);
int			PyString_AsStringAndSize(PyObject *unicode, char **tempbuffer, Py_ssize_t *length);

#endif

#if PG_VERSION_NUM < 100000
/* from src/include/access/tupdesc.h, introduced in 2cd708452 */
#define TupleDescAttr(tupdesc, i) ((tupdesc)->attrs[(i)])
#endif