/* vim: set sw=8: -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
#ifndef GNUMERIC_EXPR_H
#define GNUMERIC_EXPR_H

#include "gnumeric.h"
#include "position.h"

/* Warning: if you add something here, see do_expr_as_string * ! */
typedef enum {
	GNM_EXPR_OP_EQUAL,	/* Compare value equal */
	GNM_EXPR_OP_GT,		/* Compare value greather than  */
	GNM_EXPR_OP_LT,		/* Compare value less than */
	GNM_EXPR_OP_GTE,	/* Compare value greather or equal than */
	GNM_EXPR_OP_LTE,	/* Compare value less or equal than */
	GNM_EXPR_OP_NOT_EQUAL,	/* Compare for non equivalence */

	GNM_EXPR_OP_ADD,	/* Add  */
	GNM_EXPR_OP_SUB,	/* Subtract */
	GNM_EXPR_OP_MULT,	/* Multiply */
	GNM_EXPR_OP_DIV,	/* Divide */
	GNM_EXPR_OP_EXP,	/* Exponentiate */
	GNM_EXPR_OP_CAT,	/* String concatenation */

	GNM_EXPR_OP_FUNCALL,	/* Function call invocation */

	GNM_EXPR_OP_NAME,	/* Name reference */

        GNM_EXPR_OP_CONSTANT,	/* Constant value */
	GNM_EXPR_OP_CELLREF,	/* Cell content lookup (variable) */
	GNM_EXPR_OP_UNARY_NEG,	/* Sign inversion */
	GNM_EXPR_OP_UNARY_PLUS,	/* Mark as positive */
	GNM_EXPR_OP_PERCENTAGE,	/* Percentage (value/100) */
	GNM_EXPR_OP_ARRAY,	/* Array access */
	GNM_EXPR_OP_SET,	/* A set of expressions */
	GNM_EXPR_OP_RANGE_CTOR,	/* A constructed range eg A1:index(1,2) */
	GNM_EXPR_OP_INTERSECT	/* The intersection of multiple ranges */
} GnmExprOp;

/* Shorthands for case statements.  Easy to read, easy to maintain.  */
#define GNM_EXPR_OP_ANY_BINARY GNM_EXPR_OP_EQUAL: case GNM_EXPR_OP_GT: case GNM_EXPR_OP_LT: case GNM_EXPR_OP_GTE: \
	case GNM_EXPR_OP_LTE: case GNM_EXPR_OP_NOT_EQUAL: \
	case GNM_EXPR_OP_ADD: case GNM_EXPR_OP_SUB: case GNM_EXPR_OP_MULT: case GNM_EXPR_OP_DIV: \
	case GNM_EXPR_OP_EXP: case GNM_EXPR_OP_CAT
#define GNM_EXPR_OP_ANY_UNARY GNM_EXPR_OP_UNARY_NEG: case GNM_EXPR_OP_UNARY_PLUS : case GNM_EXPR_OP_PERCENTAGE

GnmExpr const *gnm_expr_new_constant	(GnmValue *v);
GnmExpr const *gnm_expr_new_unary	(GnmExprOp op, GnmExpr const *e);
GnmExpr const *gnm_expr_new_binary	(GnmExpr const *l, GnmExprOp op,
					 GnmExpr const *r);
GnmExpr const *gnm_expr_new_funcall	(GnmFunc *func,
					 GnmExprList *args);
GnmExpr const *gnm_expr_new_name	(GnmNamedExpr *name,
					 Sheet *sheet_scope, Workbook *wb_scope);
GnmExpr const *gnm_expr_new_cellref	(GnmCellRef const *cr);
GnmExpr const *gnm_expr_new_array	(int x, int y, int cols, int rows,
					 GnmExpr const *expr);
GnmExpr const *gnm_expr_new_set		(GnmExprList *args);

GnmExpr const *gnm_expr_first_func   (GnmExpr const *expr);
GnmValue      *gnm_expr_get_range    (GnmExpr const *expr);
GSList        *gnm_expr_get_ranges   (GnmExpr const *expr);
GnmValue const*gnm_expr_get_constant (GnmExpr const *expr);
GnmFunc       *gnm_expr_get_func_def (GnmExpr const *expr);
int            gnm_expr_get_func_argcount (GnmExpr const *expr);

void	  gnm_expr_ref		     (GnmExpr const *expr);
void	  gnm_expr_unref	     (GnmExpr const *expr);
gboolean  gnm_expr_is_shared 	     (GnmExpr const *expr);
gboolean  gnm_expr_is_rangeref 	     (GnmExpr const *expr);
gboolean  gnm_expr_is_err 	     (GnmExpr const *expr, GnmStdError e);
gboolean  gnm_expr_equal	     (GnmExpr const *a, GnmExpr const *b);
char	 *gnm_expr_as_string	     (GnmExpr const *expr, GnmParsePos const *pp,
				      GnmExprConventions const *fmt);
void      gnm_expr_as_gstring	     (GString *target,
				      GnmExpr const *expr, GnmParsePos const *pp,
				      GnmExprConventions const *fmt);
void	  gnm_expr_get_boundingbox   (GnmExpr const *expr, GnmRange *bound);
GSList	 *gnm_expr_referenced_sheets (GnmExpr const *expr);
gboolean  gnm_expr_containts_subtotal(GnmExpr const *expr);

struct _GnmExprRelocateInfo {
	GnmEvalPos pos;

	GnmRange   origin;	        /* References to cells in origin_sheet!range */
	Sheet  *origin_sheet;	/* should to adjusted */

	Sheet  *target_sheet;	/* to point at this sheet */
	int col_offset, row_offset;/* and offset by this amount */
	enum {
		GNM_EXPR_RELOCATE_STD = 0,	/* do standard relocation */
		GNM_EXPR_RELOCATE_NAME_COL = 0x1, /* col ins/del */
		GNM_EXPR_RELOCATE_NAME_ROW = 0x2  /* row ins/del */
	} type;
};

struct _GnmExprRewriteInfo {
	enum {
		GNM_EXPR_REWRITE_SHEET,
		GNM_EXPR_REWRITE_WORKBOOK,
		GNM_EXPR_REWRITE_RELOCATE
	} type;

	union {
		Sheet const     *sheet;
		Workbook const  *workbook;
		GnmExprRelocateInfo relocate;
	} u;
};

GnmExpr const *gnm_expr_rewrite	(GnmExpr const *expr,
				 GnmExprRewriteInfo const *rwinfo);

GnmValue *gnm_expr_eval (GnmExpr const *expr, GnmEvalPos const *pos,
			 GnmExprEvalFlags flags);

/*****************************************************************************/

#define gnm_expr_list_nth(l,n)	   (GnmExpr const *)g_slist_nth_data ((l), n)
#define gnm_expr_list_append(l,e)  g_slist_append ((l), (gpointer)(e))
#define gnm_expr_list_prepend(l,e) g_slist_prepend ((l), (gpointer)(e))
#define gnm_expr_list_length	   g_slist_length
#define gnm_expr_list_free	   g_slist_free
void 	 gnm_expr_list_unref	  (GnmExprList *list);
gboolean gnm_expr_list_equal	  (GnmExprList const *a, GnmExprList const *b);

/*****************************************************************************/

typedef struct {
	GHashTable *exprs, *ptrs;

	int nodes_in, nodes_stored;
} ExprTreeSharer;

ExprTreeSharer *expr_tree_sharer_new     (void);
void            expr_tree_sharer_destroy (ExprTreeSharer *);
GnmExpr const  *expr_tree_sharer_share   (ExprTreeSharer *, GnmExpr const *expr);

void expr_init (void);
void expr_shutdown (void);

#endif /* GNUMERIC_EXPR_H */