#include "inc/priv.h"
#include "inc/cvalues.h"

BUILTIN("atan", atan)
{
	argcount_least(1);
	argcount_most(2);
	if(nargs == 1)
		return mk_f64(atan(todouble(args[0])));
	return mk_f64(atan2(todouble(args[0]), todouble(args[1])));
}

BUILTIN("log", log)
{
	argcount_least(1);
	argcount_most(2);
	if(nargs == 1)
		return mk_f64(log(todouble(args[0])));
	double x = todouble(args[0]);
	if(isfixnum(args[1])){
		sl_fx b = numval(args[1]);
		if(b == 10)
			return mk_f64(log10(x));
#if !defined(__plan9__)
		if(b == 2)
			return mk_f64(log2(x));
#endif
	}
	return mk_f64(log(x) / log(todouble(args[1])));
}

#define BUILTIN_(lname, cname) \
	BUILTIN(lname, cname) \
	{ \
		argcount(1); \
		return mk_f64(cname(todouble(args[0]))); \
	}

BUILTIN_("sqrt", sqrt)
BUILTIN_("exp", exp)
BUILTIN_("sin", sin)
BUILTIN_("cos", cos)
BUILTIN_("tan", tan)
BUILTIN_("asin", asin)
BUILTIN_("acos", acos)
BUILTIN_("floor", floor)
BUILTIN_("ceiling", ceil)
BUILTIN_("sinh", sinh)
BUILTIN_("cosh", cosh)
BUILTIN_("tanh", tanh)

#undef BUILTIN_
#define BUILTIN_(lname, cname) \
	BUILTIN(lname, cname) \
	{ \
		argcount(2); \
		return mk_f64(cname(todouble(args[0]), todouble(args[1]))); \
	}

BUILTIN_("expt", pow)

void
math_init(void)
{
	setc(mk_csym("+f32-epsilon+"), mk_f32(FLT_EPSILON));
	setc(mk_csym("+f64-epsilon+"), mk_f64(DBL_EPSILON));
	setc(mk_csym("+pi+"), mk_f64(3.14159265358979323846));
}