#ifndef EXPR_H_
#define EXPR_H_

#include "config.h"
#include "Str.h"
#include "op.h"
#include "re.h"
#include "stack.h"
#include "strhash.h"
#include "val.h"
#include "variable.h"

#include <stddef.h>
#include <setjmp.h>

enum t_expr {
	literE,
	varE,
	varhashE,
	symbolE,
	unopE,
	binopE,
	listE
};

enum t_func {
	F_CALL = -1,
	F_NUL,
	F_ABS,
	F_ACOS,
	F_ASIN,
	F_ATAN,
	F_ATAN2,
	F_CATCH,
	F_CHR,
	F_COS,
	F_DEFINED,
	F_EOF,
	F_ERROR,
	F_EXP,
	F_FREEZE,
	F_GETC,
	F_GETENV,
	F_GETS,
	F_HANG,
	F_INT,
	F_IO,
	F_LENGTH,
	F_LOG,
	F_LOG10,
	F_LOWER,
	F_MATCH,
	F_MOEND,
	F_MOSTART,
	F_NEG,
	F_NOT,
	F_NUM,
	F_OPEN,
	F_OPENR,
	F_OPENW,
	F_ORD,
	F_QUOTE,
	F_RE_ESC,
	F_REMOVE,
	F_RENAME,
	F_REVERSE,
	F_SEEK,
	F_SIN,
	F_SQRT,
	F_STR,
	F_TAN,
	F_TELL,
	F_TYPEOF,
	F_UPPER
};

enum t_symbol {
	S_NUL,
	S_ARG,
	S_ARGC,
	S_ARGV,
	S_ERR,
	S_EULER,
	S_LUDOLF,
	S_MATCH,
	S_RAND,
	S_RESULT,
	S_STDIN,
	S_STDOUT,
	S_STDERR
};

enum t_binop {
	B_AMPERSAND,
	B_ANGLE,
	B_BACKSPARK,
	B_BRACELET,
	B_DOUBLE_OH_SEVEN,
	B_EMBRACE,
	B_FLATWORM,
	B_HALF_MESH,
	B_HYBRID,
	B_INTERSECTION,
	B_RIGHT_ANGLE,
	B_SHARK_FIN,
	B_SLAT,
	B_SPARK,
	B_SPARK_SPOT,
	B_SPIKE,
	B_SPLAT,
	B_SPOT,
	B_SQIGGLE,
	B_TAIL,
	B_TWO_SPOT,
	B_U_TURN,
	B_U_TURN_BACK,
	B_WORM,
	B_XMATCH
};

struct expr {
	enum t_expr type;
	int op;
	union {
		t_vr_cookie tent;
		struct val *val;
		t_strhash *hash;
	} v;
	struct expr *right;
	union {
		struct expr *expr;
		struct op *op;
		t_regex *rx;
		size_t bonus;
	} left;
};

void expr_init(void);
void expr_end(void);

void free_expr(struct expr *);
struct expr *get_expr(struct op *);
struct expr *get_lval(struct op *);
struct expr *get_iobj(struct op *);

void eval_push(struct expr *);
void eval_into(struct expr *, struct val *);
struct val *eval_pop(void);
struct val *eval_expr(struct expr *);

ATTR_PURE
enum t_binop expr_binop(int);

void expr_pp(enum t_binop, struct val *, struct val *);

typedef struct {
	jmp_buf buf;
	size_t depth;
} t_context;

stack_declare(t_context, extern)
extern stack(t_context) Context;

#define OPERATORS "_+-*/%^[]<>=!{}:;&|~`'.,"
#define OPERATOR_P(c) strchr(OPERATORS, c)

#define TOLABEL(v)                            \
do {                                          \
	V_NUM(v);                                 \
	V_xxx_OFF(v);                             \
	(v)->num = floor((v)->num + .5);          \
	(v)->type = V_NUM_K;                      \
	v_ok_str(v);                              \
	ko_grep(v->ko, isdigit);                  \
	while (ko_at(v->ko, 0) == '0') {          \
		ko_shift(v->ko, 1);                   \
	}                                         \
	(v)->type = V_STR_K;                      \
} while (0)

#endif /* EXPR_H_ */