/* Built-in functions */

#include "allobjects.h"

#include "node.h"
#include "graminit.h"
#include "errcode.h"
#include "sysmodule.h"
#include "builtinmodule.h"
#include "import.h"
#include "pythonrun.h"
#include "compile.h" /* For ceval.h */
#include "ceval.h"
#include "modsupport.h"

static object *
builtin_abs(self, v)
	object *self;
	object *v;
{
	/* XXX This should be a method in the as_number struct in the type */
	if (v == NULL) {
		/* */
	}
	else if (is_intobject(v)) {
		long x = getintvalue(v);
		if (x < 0)
			x = -x;
		return newintobject(x);
	}
	else if (is_floatobject(v)) {
		double x = getfloatvalue(v);
		if (x < 0)
			x = -x;
		return newfloatobject(x);
	}
	err_setstr(TypeError, "abs() argument must be float or int");
	return NULL;
}

static object *
builtin_chr(self, v)
	object *self;
	object *v;
{
	long x;
	char s[1];
	if (v == NULL || !is_intobject(v)) {
		err_setstr(TypeError, "chr() must have int argument");
		return NULL;
	}
	x = getintvalue(v);
	if (x < 0 || x >= 256) {
		err_setstr(RuntimeError, "chr() arg not in range(256)");
		return NULL;
	}
	s[0] = x;
	return newsizedstringobject(s, 1);
}

static object *
builtin_dir(self, v)
	object *self;
	object *v;
{
	object *d;
	if (v == NULL) {
		d = getlocals();
	}
	else {
		if (!is_moduleobject(v)) {
			err_setstr(TypeError,
				"dir() argument, must be module or absent");
			return NULL;
		}
		d = getmoduledict(v);
	}
	v = getdictkeys(d);
	if (sortlist(v) != 0) {
		DECREF(v);
		v = NULL;
	}
	return v;
}

static object *
builtin_divmod(self, v)
	object *self;
	object *v;
{
	object *x, *y;
	long xi, yi, xdivy, xmody;
	if (v == NULL || !is_tupleobject(v) || gettuplesize(v) != 2) {
		err_setstr(TypeError, "divmod() requires 2 int arguments");
		return NULL;
	}
	x = gettupleitem(v, 0);
	y = gettupleitem(v, 1);
	if (!is_intobject(x) || !is_intobject(y)) {
		err_setstr(TypeError, "divmod() requires 2 int arguments");
		return NULL;
	}
	xi = getintvalue(x);
	yi = getintvalue(y);
	if (yi == 0) {
		err_setstr(TypeError, "divmod() division by zero");
		return NULL;
	}
	if (yi < 0) {
		xdivy = -xi / -yi;
	}
	else {
		xdivy = xi / yi;
	}
	xmody = xi - xdivy*yi;
	if (xmody < 0 && yi > 0 || xmody > 0 && yi < 0) {
		xmody += yi;
		xdivy -= 1;
	}
	v = newtupleobject(2);
	x = newintobject(xdivy);
	y = newintobject(xmody);
	if (v == NULL || x == NULL || y == NULL ||
		settupleitem(v, 0, x) != 0 ||
		settupleitem(v, 1, y) != 0) {
		XDECREF(v);
		XDECREF(x);
		XDECREF(y);
		return NULL;
	}
	return v;
}

static object *
exec_eval(v, start)
	object *v;
	int start;
{
	object *str = NULL, *globals = NULL, *locals = NULL;
	int n;
	if (v != NULL) {
		if (is_stringobject(v))
			str = v;
		else if (is_tupleobject(v) &&
				((n = gettuplesize(v)) == 2 || n == 3)) {
			str = gettupleitem(v, 0);
			globals = gettupleitem(v, 1);
			if (n == 3)
				locals = gettupleitem(v, 2);
		}
	}
	if (str == NULL || !is_stringobject(str) ||
			globals != NULL && !is_dictobject(globals) ||
			locals != NULL && !is_dictobject(locals)) {
		err_setstr(TypeError,
		    "exec/eval arguments must be string[,dict[,dict]]");
		return NULL;
	}
	return run_string(getstringvalue(str), start, globals, locals);
}

static object *
builtin_eval(self, v)
	object *self;
	object *v;
{
	return exec_eval(v, eval_input);
}

static object *
builtin_exec(self, v)
	object *self;
	object *v;
{
	return exec_eval(v, file_input);
}

static object *
builtin_float(self, v)
	object *self;
	object *v;
{
	if (v == NULL) {
		/* */
	}
	else if (is_floatobject(v)) {
		INCREF(v);
		return v;
	}
	else if (is_intobject(v)) {
		long x = getintvalue(v);
		return newfloatobject((double)x);
	}
	err_setstr(TypeError, "float() argument must be float or int");
	return NULL;
}

static object *
builtin_input(self, v)
	object *self;
	object *v;
{
	FILE *in = sysgetfile("stdin", stdin);
	FILE *out = sysgetfile("stdout", stdout);
	node *n;
	int err;
	object *m, *d;
	flushline();
	if (v != NULL)
		printobject(v, out, PRINT_RAW);
	m = add_module("__main__");
	d = getmoduledict(m);
	return run_file(in, "<stdin>", expr_input, d, d);
}

static object *
builtin_int(self, v)
	object *self;
	object *v;
{
	if (v == NULL) {
		/* */
	}
	else if (is_intobject(v)) {
		INCREF(v);
		return v;
	}
	else if (is_floatobject(v)) {
		double x = getfloatvalue(v);
		return newintobject((long)x);
	}
	err_setstr(TypeError, "int() argument must be float or int");
	return NULL;
}

static object *
builtin_len(self, v)
	object *self;
	object *v;
{
	long len;
	typeobject *tp;
	if (v == NULL) {
		err_setstr(TypeError, "len() without argument");
		return NULL;
	}
	tp = v->ob_type;
	if (tp->tp_as_sequence != NULL) {
		len = (*tp->tp_as_sequence->sq_length)(v);
	}
	else if (tp->tp_as_mapping != NULL) {
		len = (*tp->tp_as_mapping->mp_length)(v);
	}
	else {
		err_setstr(TypeError, "len() of unsized object");
		return NULL;
	}
	return newintobject(len);
}

static object *
min_max(v, sign)
	object *v;
	int sign;
{
	int i, n, cmp;
	object *w, *x;
	sequence_methods *sq;
	if (v == NULL) {
		err_setstr(TypeError, "min() or max() without argument");
		return NULL;
	}
	sq = v->ob_type->tp_as_sequence;
	if (sq == NULL) {
		err_setstr(TypeError, "min() or max() of non-sequence");
		return NULL;
	}
	n = (*sq->sq_length)(v);
	if (n == 0) {
		err_setstr(RuntimeError, "min() or max() of empty sequence");
		return NULL;
	}
	w = (*sq->sq_item)(v, 0); /* Implies INCREF */
	for (i = 1; i < n; i++) {
		x = (*sq->sq_item)(v, i); /* Implies INCREF */
		cmp = cmpobject(x, w);
		if (cmp * sign > 0) {
			DECREF(w);
			w = x;
		}
		else
			DECREF(x);
	}
	return w;
}

static object *
builtin_min(self, v)
	object *self;
	object *v;
{
	return min_max(v, -1);
}

static object *
builtin_max(self, v)
	object *self;
	object *v;
{
	return min_max(v, 1);
}

static object *
builtin_open(self, v)
	object *self;
	object *v;
{
	object *name, *mode;
	if (v == NULL || !is_tupleobject(v) || gettuplesize(v) != 2 ||
		!is_stringobject(name = gettupleitem(v, 0)) ||
		!is_stringobject(mode = gettupleitem(v, 1))) {
		err_setstr(TypeError, "open() requires 2 string arguments");
		return NULL;
	}
	v = newfileobject(getstringvalue(name), getstringvalue(mode));
	return v;
}

static object *
builtin_ord(self, v)
	object *self;
	object *v;
{
	if (v == NULL || !is_stringobject(v)) {
		err_setstr(TypeError, "ord() must have string argument");
		return NULL;
	}
	if (getstringsize(v) != 1) {
		err_setstr(RuntimeError, "ord() arg must have length 1");
		return NULL;
	}
	return newintobject((long)(getstringvalue(v)[0] & 0xff));
}

static object *
builtin_range(self, v)
	object *self;
	object *v;
{
	static char *errmsg = "range() requires 1-3 int arguments";
	int i, n;
	long ilow, ihigh, istep;
	if (v != NULL && is_intobject(v)) {
		ilow = 0; ihigh = getintvalue(v); istep = 1;
	}
	else if (v == NULL || !is_tupleobject(v)) {
		err_setstr(TypeError, errmsg);
		return NULL;
	}
	else {
		n = gettuplesize(v);
		if (n < 1 || n > 3) {
			err_setstr(TypeError, errmsg);
			return NULL;
		}
		for (i = 0; i < n; i++) {
			if (!is_intobject(gettupleitem(v, i))) {
				err_setstr(TypeError, errmsg);
				return NULL;
			}
		}
		if (n == 3) {
			istep = getintvalue(gettupleitem(v, 2));
			--n;
		}
		else
			istep = 1;
		ihigh = getintvalue(gettupleitem(v, --n));
		if (n > 0)
			ilow = getintvalue(gettupleitem(v, 0));
		else
			ilow = 0;
	}
	if (istep == 0) {
		err_setstr(RuntimeError, "zero step for range()");
		return NULL;
	}
	/* XXX ought to check overflow of subtraction */
	if (istep > 0)
		n = (ihigh - ilow + istep - 1) / istep;
	else
		n = (ihigh - ilow + istep + 1) / istep;
	if (n < 0)
		n = 0;
	v = newlistobject(n);
	if (v == NULL)
		return NULL;
	for (i = 0; i < n; i++) {
		object *w = newintobject(ilow);
		if (w == NULL) {
			DECREF(v);
			return NULL;
		}
		setlistitem(v, i, w);
		ilow += istep;
	}
	return v;
}

static object *
builtin_raw_input(self, v)
	object *self;
	object *v;
{
	FILE *in = sysgetfile("stdin", stdin);
	FILE *out = sysgetfile("stdout", stdout);
	char *p;
	int err;
	int n = 1000;
	flushline();
	if (v != NULL)
		printobject(v, out, PRINT_RAW);
	v = newsizedstringobject((char *)NULL, n);
	if (v != NULL) {
		if ((err = fgets_intr(getstringvalue(v), n+1, in)) != E_OK) {
			err_input(err);
			DECREF(v);
			return NULL;
		}
		else {
			n = strlen(getstringvalue(v));
			if (n > 0 && getstringvalue(v)[n-1] == '\n')
				n--;
			resizestring(&v, n);
		}
	}
	return v;
}

static object *
builtin_reload(self, v)
	object *self;
	object *v;
{
	return reload_module(v);
}

static object *
builtin_type(self, v)
	object *self;
	object *v;
{
	if (v == NULL) {
		err_setstr(TypeError, "type() requres an argument");
		return NULL;
	}
	v = (object *)v->ob_type;
	INCREF(v);
	return v;
}

static struct methodlist builtin_methods[] = {
	{"abs", builtin_abs},
	{"chr", builtin_chr},
	{"dir", builtin_dir},
	{"divmod", builtin_divmod},
	{"eval", builtin_eval},
	{"exec", builtin_exec},
	{"float", builtin_float},
	{"input", builtin_input},
	{"int", builtin_int},
	{"len", builtin_len},
	{"min", builtin_min},
	{"max", builtin_max},
	{"open", builtin_open}, /* XXX move to OS module */
	{"ord", builtin_ord},
	{"range", builtin_range},
	{"raw_input", builtin_raw_input},
	{"reload", builtin_reload},
	{"type", builtin_type},
	{NULL, NULL},
};

static object *builtin_dict;

object *
getbuiltin(name)
	char *name;
{
	return dictlookup(builtin_dict, name);
}

/* Predefined exceptions */

object *RuntimeError;
object *EOFError;
object *TypeError;
object *MemoryError;
object *NameError;
object *SystemError;
object *KeyboardInterrupt;

static object *
newstdexception(name, message)
	char *name, *message;
{
	object *v = newstringobject(message);
	if (v == NULL || dictinsert(builtin_dict, name, v) != 0)
		fatal("no mem for new standard exception");
	return v;
}

static void
initerrors()
{
	RuntimeError = newstdexception("RuntimeError", "run-time error");
	EOFError = newstdexception("EOFError", "end-of-file read");
	TypeError = newstdexception("TypeError", "type error");
	MemoryError = newstdexception("MemoryError", "out of memory");
	NameError = newstdexception("NameError", "undefined name");
	SystemError = newstdexception("SystemError", "system error");
	KeyboardInterrupt =
		newstdexception("KeyboardInterrupt", "keyboard interrupt");
}

void
initbuiltin()
{
	object *m;
	m = initmodule("builtin", builtin_methods);
	builtin_dict = getmoduledict(m);
	INCREF(builtin_dict);
	initerrors();
	(void) dictinsert(builtin_dict, "None", None);
}