use super::funejson::Value;
use super::math_rational_rational::{rational, rational_from_value};
use super::math_round_div::round_div;

/// The integer a fraction rounds to, under an explicit rounding mode: the
/// point where an exact rate becomes minor units, so the policy is the
/// caller's to state.
///
/// # Panics
/// Panics on a zero denominator, a part outside ±(2^53 - 1), or an unknown mode.
pub fn rational_to_integer(r: &Rational, mode: &str) -> i64 {
    let n = rational(r.numerator, r.denominator);
    round_div(n.numerator, n.denominator, mode)
}

pub fn fune_vector(args: &[Value]) -> Value {
    Value::Int(rational_to_integer(&rational_from_value(&args[0]), args[1].as_str()))
}